Bone Health

Estrogen, bone density, fracture risk, and the effect of suppressive medications and life stage on the skeleton.

171 articles

Bone Mineral Density · Measurement

Longitudinal Assessment of Bone Mineral Density in Women Living With and Without HIV Across Reproductive Phases

Swann SA et al., 2024 J Acquir Immune Defic Syndr

Women living with HIV commonly experience low areal bone mineral density (BMD), but whether this is affected by low ovarian hormonal states (prolonged amenorrhea or menopause) is unknown. We compared rates of BMD loss between women living with HIV and HIV-negative control women and investigated its association with low ovarian hormonal states. Women living with HIV were enrolled from Vancouver Canada and controls from 9 Canadian sites. This longitudinal analysis included age-matched women living with HIV in the Children and Women: AntiRetrovirals and Markers of Aging cohort and controls in the population-based Canadian Multicentre Osteoporosis Study. Rate of change/year in BMD at the total hip and lumbar spine (L1-L4) between 3 and 5 years was compared between groups, adjusting for sociodemographic and clinical variables. Ninety-two women living with HIV (median [interquartile range] age: 49.5 [41.6-54.1] years and body mass index: 24.1 [20.7-30.8] kg/m 2 ) and 278 controls (age: 49.0 [43.0-55.0] years and body mass index: 25.8 [22.9-30.6] kg/m 2 ) were included. Total hip BMD loss was associated with HIV (β: -0.003 [95% CI: -0.006 to -0.0001] g/cm 2 /yr), menopause (β: -0.007 [-0.01 to -0.005] g/cm 2 /yr), and smoking (β: -0.003 [-0.006 to -0.0002] g/cm 2 /yr); BMD gain was linked with higher body mass index (β: 0.0002 [0.0007-0.0004] g/cm 2 /yr). Menopause was associated with losing L1-L4 BMD (β: -0.01 [-0.01 to -0.006] g/cm 2 /yr). Amenorrhea was not associated with BMD loss. HIV and menopause negatively influenced total hip BMD. These data suggest women living with HIV require hip BMD monitoring as they age.

Bone Mineral Density · Measurement

Long-Term Change in Bone Mineral Density in Women Living With HIV: A 10-Year Prospective Controlled Cohort Study

Macdonald HM et al., 2023 JBMR Plus Open Access

Women living with HIV (WLWH) may be at higher risk for osteoporosis and fragility fractures. However, limited prospective data describe long-term trajectories of bone mineral density (BMD) in WLWH versus women without HIV. Thus, in this prospective study, we aimed to compare 10-year change in areal BMD (aBMD) between WLWH (n = 49; 36.8 ± 8.8 years; 96% pre/perimenopausal) and HIV-negative women (population-based controls; n = 49; 41.9 ± 9.2 years; 80% pre/perimenopausal). In an exploratory analysis, we compared fracture history between WLWH and controls. Outcomes were lumbar spine (L(1) to L(4)), total hip, and femoral neck aBMD at baseline and follow-up, which occurred at 13 and 10 years in WLWH and controls, respectively. We fit multivariable regression models to compare baseline and 10-year change in aBMD between groups, adjusting for osteoporosis risk factors. Within WLWH, we examined associations between aBMD and HIV-related factors, including combination antiretroviral therapy (cART) duration. WLWH were diagnosed 6.5 ± 3.7 years before baseline, 80% were on cART for 241 ± 142 weeks, and 49% had HIV plasma viral load <40 copies/mL. Before and after adjusting for osteoporosis risk factors, baseline and 10-year change in aBMD did not differ between WLWH and controls at any site. At baseline, more WLWH than controls reported a history of low-trauma fracture (30% versus 10%, p < 0.05) and major osteoporotic fracture (17% versus 4%, p < 0.05). During follow-up, the number of WLWH and controls with incident fragility fracture was not significantly different. Lifetime cART duration and tenofovir use were not associated with aBMD 10-year percent change. Higher CD4 count at baseline was positively associated with femoral neck aBMD 10-year percent change. Long-term aBMD change in this small WLWH cohort paralleled normal aging, with no evidence of influence from cART use; however, these results should be interpreted with caution given the small sample size. Larger cohort studies are needed to confirm these findings.

Hormones and Bone · Contraceptive Effects on Bone

Bone health and prevalent fractures in women with polycystic ovary syndrome: a meta-analysis and endocrine-context pathophysiology review

Prior JC et al., 2023 Expert Rev Endocrinol Metab

Bone health in those with Polycystic Ovary Syndrome (PCOS) is complex, but the general consensus is that cortical areal bone mineral density (aBMD) sites will be higher in PCOS than in ageand BMI-similar controls. However, spine aBMD sites may be lower, especially in non-obese PCOS. Whether or not incident fracture risk is increased in PCOS is currently controversial; no meta-analysis has yet assessed prevalent fractures. We assessed the bone effects of PCOS-related ovarian hormone alterations, e.g. androgen excess, tonically normal/higher estradiol, and lower-than-normal progesterone levels. We also highlighted evidence that common PCOS medications (e.g. combined hormonal contraceptives [CHC], metformin, and spironolactone) have important bone effects. In adolescents, meta-analysis of CHC showed significant negative aBMD changes. Inflammation has negative PCOS bone effects and is linked with CHC use. EXPERT Opinion: Is fracture risk altered by PCOS? Our meta-analysis showed a 25% increased risk of prevalent fracture in PCOS versus controls; this did not reach statistical significance. Future prospective research needs to collect and evaluate ovulation characteristics, progesterone exposure, and adolescent CHC use, in addition to the complex variables that may influence risks for prevalent or incident fragility fractures and/or for cortical and cancellous aBMD values in PCOS.

Hormones and Bone · Contraceptive Effects on Bone

Combined hormonal contraceptive use is not protective against musculoskeletal conditions or injuries: a systematic review with data from 5 million females

White L et al., 2023 Br J Sports Med

Assess the association between combined hormonal contraceptives (CHC) use and musculoskeletal tissue pathophysiology, injuries or conditions. Systematic review with semiquantitative analyses and certainty of evidence assessment, guided by the Grading of Recommendations Assessment, Development and Evaluation approach. Data Sources: MEDLINE, EMBASE, CENTRAL, SPORTDiscus, CINAHL searched from inception to April 2022. Intervention and cohort studies that assessed the association between new or ongoing use of CHC and an outcome of musculoskeletal tissue pathophysiology, injury or condition in postpubertal premenopausal females. Across 50 included studies, we assessed the effect of CHC use on 30 unique musculoskeletal outcomes (75% bone related). Serious risk of bias was judged present in 82% of studies, with 52% adequately adjusting for confounding. Meta-analyses were not possible due to poor outcome reporting, and heterogeneity in estimate statistics and comparison conditions. Based on semiquantitative synthesis, there is low certainty evidence that CHC use was associated with elevated future fracture risk (risk ratio 1.02-1.20) and total knee arthroplasty (risk ratio 1.00-1.36). There is very low certainty evidence of unclear relationships between CHC use and a wide range of bone turnover and bone health outcomes. Evidence about the effect of CHC use on musculoskeletal tissues beyond bone, and the influence of CHC use in adolescence versus adulthood, is limited. Given a paucity of high certainty evidence that CHC use is protective against musculoskeletal pathophysiology, injury or conditions, it is premature and inappropriate to advocate, or prescribe CHC for these purposes. This review was registered on PROSPERO CRD42021224582 on 8 January 2021.

Bone Mineral Density · Peak Bone Mass

Impact of gender-affirming treatment on bone health in transgender and gender diverse youth

Ciancia S et al., 2022 Endocrine connections

Both in the United States and Europe, the number of minors who present at transgender healthcare services before the onset of puberty is rapidly expanding. Many of those who will have persistent gender dysphoria at the onset of puberty will pursue long-term puberty suppression before reaching the appropriate age to start using gender-affirming hormones. Exposure to pubertal sex steroids is thus significantly deferred in these individuals. Puberty is a critical period for bone development: increasing concentrations of estrogens and androgens (directly or after aromatization to estrogens) promote progressive bone growth and mineralization and induce sexually dimorphic skeletal changes. As a consequence, safety concerns regarding bone development and increased future fracture risk in transgender youth have been raised. We here review published data on bone development in transgender adolescents, focusing in particular on differences in age and pubertal stage at the start of puberty suppression, chosen strategy to block puberty progression, duration of puberty suppression, and the timing of re-evaluation after estradiol or testosterone administration. Results consistently indicate a negative impact of long-term puberty suppression on bone mineral density, especially at the lumbar spine, which is only partially restored after sex steroid administration. Trans girls are more vulnerable than trans boys for compromised bone health. Behavioral health measures that can promote bone mineralization, such as weight-bearing exercise and calcium and vitamin D supplementation, are strongly recommended in transgender youth, during the phase of puberty suppression and thereafter.

Bone Mineral Density · Measurement

Reply to: The Association Between Cognitive Decline and Bone Loss and Fracture Risk Is Not Affected by Medication With Anticholinergic Effect

Bliuc D et al., 2022 J Bone Miner Res

To the Editors: We are grateful to Dr. Naharci for the interest in our study reporting the association between cognitive decline and bone loss and fracture risk. (1) We agree that bisphosphonates (BPs) have a proven effect on reducing bone loss and fracture risk. (2) Medication with anticholinergic (ACH) side effects may also affect cogni-tive function as well as propensity to fall and fracture, although these effects have not been demonstrated in all studies. (3) We did not include these medication classes in our models because in observational studies the relationship between medication and outcomes is likely driven by factors associated with medication use. This bias by indication can only be avoided by specific study design (ie, propensity score matching), which was beyond the scope of our study. (4) However, we have conducted additional analyses to determine the prevalence of BP and ACH medication in our cohort, the association between these medication classes and our study outcomes and the impact of the addition of these medication classes to our findings. BP and ACH use were self-reported and obtained by questionnaire at baseline, and years 5 and 10. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry (DXA) and cognitive function using the Mini Mental State Examination (MMSE) test during all clinical visits. Follow-up time for BMD

Osteoporosis · Diagnosis and Treatment

Cognitive decline is associated with an accelerated rate of bone loss and increased fracture risk in women: a prospective study from the Canadian Multicentre Osteoporosis Study

Bliuc D et al., 2021 J Bone Miner Res

Cognitive decline and osteoporosis often coexist and some evidence suggests a causal link. However, there are no data on the longitudinal relationship between cognitive decline, bone loss and fracture risk, independent of aging. This study aimed to determine the association between: (i) cognitive decline and bone loss; and (ii) clinically significant cognitive decline (≥3 points) on Mini Mental State Examination (MMSE) over the first 5 years and subsequent fracture risk over the following 10 years. A total of 1741 women and 620 men aged ≥65 years from the population-based Canadian Multicentre Osteoporosis Study were followed from 1997 to 2013. Association between cognitive decline and (i) bone loss was estimated using mixed-effects models; and (ii) fracture risk was estimated using adjusted Cox models. Over 95% of participants had normal cognition at baseline (MMSE ≥ 24). The annual % change in MMSE was similar for both genders (women -0.33, interquartile range [IQR] -0.70 to +0.00; and men -0.34, -0.99 to 0.01). After multivariable adjustment, cognitive decline was associated with bone loss in women (6.5%; 95% confidence interval [CI], 3.2% to 9.9% for each percent decline in MMSE from baseline) but not men. Approximately 13% of participants experienced significant cognitive decline by year 5. In women, fracture risk was increased significantly (multivariable hazard ratio [HR], 1.61; 95% CI, 1.11 to 2.34). There were too few men to analyze. There was a significant association between cognitive decline and both bone loss and fracture risk, independent of aging, in women. Further studies are needed to determine mechanisms that link these common conditions.

Bone Mineral Density · Measurement

Faster Lumbar Spine Bone Loss in Midlife Predicts Subsequent Fracture Independent of Starting Bone Mineral Density

Shieh A et al., 2021 The Journal of clinical endocrinology and metabolism Open Access

Bone mineral density (BMD) decreases rapidly during menopause transition (MT), and continues to decline in postmenopause. This work aims to examine whether faster BMD loss during the combined MT and early postmenopause is associated with incident fracture, independent of starting BMD, before the MT. The Study of Women's Health Across the Nation, a longitudinal cohort study, included 451 women, initially premenopausal or early perimenopausal, and those transitioned to postmenopause. Main outcome measures included time to first fracture after early postmenopause. In Cox proportional hazards regression, adjusted for age, body mass index, race/ethnicity, study site, use of vitamin D and calcium supplements, and use of bone-detrimental or -beneficial medications, each SD decrement in lumbar spine (LS) BMD before MT was associated with a 78% increment in fracture hazard (P = .007). Each 1% per year faster decline in LS BMD was related to a 56% greater fracture hazard (P = .04). Rate of LS BMD decline predicted future fracture, independent of starting BMD. Women with a starting LS BMD below the sample median, and an LS BMD decline rate faster than the sample median had a 2.7-fold greater fracture hazard (P = .03). At the femoral neck, neither starting BMD nor rate of BMD decline was associated with fracture. At the LS, starting BMD before the MT and rate of decline during the combined MT and early postmenopause are independent risk factors for fracture. Women with a below-median starting LS BMD and a faster-than-median LS BMD decline have the greatest fracture risk.

Osteoporosis · Diagnosis and Treatment

Simulated effects of early menopausal bone mineral density preservation on long-term fracture risk: a feasibility study

Billington EO et al., 2021 Osteoporos Int

Prevention of early menopausal bone loss may reduce the future burden of osteoporosis. In this modelling exercise, an osteoporosis prevention strategy involving 5-year infusions of zoledronic acid, beginning early in menopause, reduced long-term fracture risk and the proportion of aging women with femoral neck densitometric osteoporosis. This strategy warrants further evaluation. Preventing early menopausal bone loss may substantially reduce the future burden of osteoporosis. We modelled the effects of infrequent zoledronic acid infusions on long-term fracture risk. Data from the Canadian Multicentre Osteoporosis Study (CaMos) were used to determine the expected natural history of femoral neck areal bone mineral density (BMD) and fracture risk (using FRAX®) from ages 50-80 for women with no antiresorptive drug exposures. We modelled the effects of three infusions of zoledronic acid (at ages 50, 55, 60) on long-term fracture risk, assuming this intervention would preserve BMD until age 65 years, followed by losses mirroring early menopausal BMD loss. At age 65, untreated women and zoledronic acid recipients had expected mean (SD) femoral neck T-scores of - 1.5(1.0) and - 0.8(1.0), 10-year major osteoporotic fracture (MOF) risks of 9.8%(5.0) and 8.0%(3.7) and hip fracture risks of 1.7%(2.4) and 0.8%(1.2), respectively. At age 80, untreated women and zoledronic acid recipients had expected femoral neck T-scores of - 1.9(0.9) and - 1.4(0.9), MOF risks of 17.9%(8.2) and 14.9%(6.4) and hip fracture risks of 6.3%(6.2) and 4.4%(4.5), respectively. The expected proportion of women with femoral neck T-score ≤ - 2.5 was 14.9% for untreated women and 3.8% for zoledronic acid recipients at age 65, increasing to 28.1% and 12.0%, respectively, at age 80. Numbers-needed-to-treat to prevent one case of densitometric osteoporosis were 9 at age 65 and 5 at age 80. Infrequent infusions of zoledronic acid, initiated early in menopause, are expected to reduce long-term fracture risk and result in a substantial reduction in the proportion of women with densitometric osteoporosis after age 65.

Osteoporosis · Diagnosis and Treatment

Vertebral Fractures: Which Radiological Criteria Are Better Associated With the Clinical Course of Osteoporosis?

Lentle BC et al., 2021 Can Assoc Radiol J

Study purposeMorphometric methods categorize potential osteoporotic vertebral fractures (OVF) on the basis of loss of vertebral height. A particular example is the widely used semiquantitative morphometric tool proposed by Genant (GSQ). A newer morphologic algorithm-based qualitative (mABQ) tool focuses on vertebral end-plate damage in recognizing OVF. We used data from both sexes in the Canadian Multicentre Osteoporosis Study (CaMos) to compare the 2 methods in identifying OVF at baseline and during 10 years of follow-up. We obtained lateral thoracic and lumbar spinal radiographs (T4-L4) 3 times, at 5-year intervals, in 828 participants of the population-based CaMos. Logistic regressions were used to study the association of 10-year changes in bone mineral density (BMD) with incident fractures. At baseline, 161 participants had grade 1 and 32 had grade 2 GSQ OVF; over the next 10 years, only 9 of these participants had sustained incident GSQ OVF. Contrastingly, 21 participants at baseline had grade 1 and 48 grade 2 mABQ events; over the next 10 years, 79 subjects experienced incident grade 1 or grade 2 mABQ events. Thus, incident grades 1 and 2 morphologic fractures were 8 times more common than morphometric deformities alone. Each 10-year decrease of 0.01 g/cm2 in total hip BMD was associated with a 4.1% (95% CI: 0.7-7.3) higher odds of having an incident vertebral fracture. This analysis further suggests that morphometric deformities and morphologic fractures constitute distinct entities; morphologic fractures conform more closely to the expected epidemiology of OVF.

Osteoporosis · Diagnosis and Treatment

Differences in fracture prevalence and in bone mineral density between Chinese and White Canadians: the Canadian Multicentre Osteoporosis Study (CaMos)

Morin SN et al., 2020 Arch Osteoporos

Fracture determinants differ between Canadians of Chinese and White descent, the former constituting the second largest visible minority group in Canada. The results of this study support the importance of characterizing bone health predictors in Canadians of different ethnicity to improve population-specific fracture prevention and treatment strategies. We aimed to compare clinical risk factors, bone mineral density, prevalence of osteoporosis, and fractures between Chinese and White Canadians to identify ethnicity-specific risks. We studied 236 Chinese and 8945 White Canadians aged 25+ years from the Canadian Multicentre Osteoporosis Study (CaMos). The prevalence of osteoporosis using ethnicity-specific peak bone mass (PBM), and of prior and incident low trauma fractures were assessed and compared between groups. Linear regressions, adjusting for age and anthropometric measures, were used to examine the association between baseline and 5-year changes in BMD and ethnicity. Chinese participants had shorter stature, lower BMI, and lower rate of falls than White participants. Adjusted models showed no significant differences in baseline BMD between ethnic groups except in younger men where total hip BMD was 0.059 g/cm2 (0.009; 0.108) lower in Chinese. Adjusted 5-year BMD change at lumbar spine was higher in older Chinese women and men compared with Whites. When using Chinese-specific PBM, the prevalence of osteoporosis in Chinese women was 2-fold lower than when using that of White women The prevalence of fractures was higher in White women compared with Chinese with differences up to 14.5% (95% CI 9.2; 19.7) and 10.5% (95% CI 4.5-16.4) in older White men. Incident fractures were rare in young Chinese compared with White participants and not different in the older groups. Our results support the importance of characterizing bone strength predictors in Chinese Canadians and the development of ethnicity-specific fracture prediction and prevention strategies.

Fracture Risk · Risk Factors

A Risk Assessment Tool for Predicting Fragility Fractures and Mortality in the Elderly

Tran T et al., 2020 J Bone Miner Res

Existing fracture risk assessment tools are not designed to predict fracture-associated consequences, possibly contributing to the current undermanagement of fragility fractures worldwide. We aimed to develop a risk assessment tool for predicting the conceptual risk of fragility fractures and its consequences. The study involved 8965 people aged ≥60 years from the Dubbo Osteoporosis Epidemiology Study and the Canadian Multicentre Osteoporosis Study. Incident fracture was identified from X-ray reports and questionnaires, and death was ascertained though contact with a family member or obituary review. We used a multistate model to quantify the effects of the predictors on the transition risks to an initial and subsequent incident fracture and mortality, accounting for their complex interrelationships, confounding effects, and death as a competing risk. There were 2364 initial fractures, 755 subsequent fractures, and 3300 deaths during a median follow-up of 13 years (interquartile range [IQR] 7-15). The prediction model included sex, age, bone mineral density, history of falls within 12 previous months, prior fracture after the age of 50 years, cardiovascular diseases, diabetes mellitus, chronic pulmonary diseases, hypertension, and cancer. The model accurately predicted fragility fractures up to 11 years of follow-up and post-fracture mortality up to 9 years, ranging from 7 years after hip fractures to 15 years after non-hip fractures. For example, a 70-year-old woman with a T-score of -1.5 and without other risk factors would have 10% chance of sustaining a fracture and an 8% risk of dying in 5 years. However, after an initial fracture, her risk of sustaining another fracture or dying doubles to 33%, ranging from 26% after a distal to 42% post hip fracture. A robust statistical technique was used to develop a prediction model for individualization of progression to fracture and its consequences, facilitating informed decision making about risk and thus treatment for individuals with different risk profiles.

Bone Mineral Density · Measurement

Deficits in bone strength, density and microarchitecture in women living with HIV: A cross-sectional HR-pQCT study

Macdonald HM et al., 2020 Bone

With the advent of combined antiretroviral therapy (cART), life expectancy has increased among persons living with HIV, but so too has risk for comorbidities including osteoporosis and fragility fracture. To explore whether HIV status and cART influence three-dimensional measures of BMD, bone microarchitecture and strength we aimed to compare these outcomes between women living with HIV (WLWH; n = 50; 50.4 ± 1.2 years, 44% postmenopausal) and without HIV (controls; n = 50; 51.8 ± 1.2 years, 52% postmenopausal). Outcomes were lumbar spine, total hip and femoral neck areal BMD by DXA; distal radius and tibia trabecular BMD, thickness and number, and cortical BMD and area by HR-pQCT; and finite element analysis-derived bone strength (failure load). Multivariable regression analysis compared bone outcomes between groups adjusting for known osteoporosis risk factors. Within WLWH, we examined associations between bone outcomes and HIV-related factors including disease severity and cART duration. WLWH were diagnosed 20 ± 4 years ago, were on cART for 123 ± 37 months and 80% had HIV plasma viral load <40 copies/mL. For women ≥50 years (n = 61), total hip aBMD T-Score was lower among WLWH than controls. Adjusted distal radius trabecular BMD and thickness and distal tibia trabecular BMD and failure load were 8-19% lower in WLWH than controls (p < 0.05). Cortical BMD and area did not differ between groups at either site. Lifetime cART duration and current plasma viral load were not associated with bone outcomes in WLWH; however, previous treatment with tenofovir was negatively associated with distal radius trabecular BMD and trabecular number and LS aBMD T-score. WLWH have compromised BMD, bone microarchitecture and strength vs. controls of similar age and reproductive status. Treatment with tenofovir may contribute to bone deficits in WLWH.

Hormones and Bone · Estrogen and Bone

Effects of progesterone therapy on serum sclerostin levels in healthy menopausal women: a 3-month randomized, placebo-controlled clinical trial

Yang YB et al., 2020 Osteoporos Int

Sclerostin, a natural hormone made in bone, suppresses bone formation. Sclerostin is also decreased by estrogen. Progesterone, estrogen's menstrual partner, stimulates bone formation. It is unclear whether progesterone influences sclerostin. This study showed that progesterone did not change sclerostin using serum remaining from a randomized progesterone hot flush therapy trial. Progesterone and sclerostin are both endogenous hormones acting through osteoblast-origin cells and promote or suppress bone formation, respectively. Estradiol suppresses sclerostin, but progesterone, its menstrual cycle partner hormone, has unclear sclerostin relationships. We postulated that progesterone therapy would influence serum sclerostin levels. We obtained sclerostin levels for an ethics-approved post hoc analysis. Fasting sclerostin was measured in all remaining sera from a previous 12-week randomized controlled trial (RCT) of oral micronized progesterone (progesterone) for menopausal (> 1 year after last flow) vasomotor symptoms (VMS). Women in the RCT took 300 mg progesterone at bedtime or placebo (1:1) in a trial showing progesterone significantly decreased VMS. Participants were healthy menopausal, primarily Caucasian (91.2%) community-dwelling women (± SD), 55.2 ± 4.6 years old with BMI 24.9 ± 2.9 kg/m(2). The baseline sclerostin level in 60 women was 28.41 ± 10.47 pmol/L. Baseline sclerostin was not correlated with the run-in VMS score (r = 0.143, P = 0.294). Paired baseline and 12-week RCT data for 52 women showed serum sclerostin levels did not change related to experimental therapy (P = 0.504). Changes in final sclerostin values adjusted for baseline were progesterone (- 1.07 ± 7.96 pmol/L) and placebo (- 2.64 ± 8.70 pmol/L). In observational data (n = 60), baseline sclerostin levels correlated with the General Framingham Cardiovascular (CVD) Risk score (r = - 0.398, P = 0.003) and self-reported health by SF-36 quality of life instrument (QoL, r = - 0.331, P = 0.016). Physiological oral micronized progesterone did not stimulate nor suppress serum sclerostin levels based on post hoc analysis of RCT data. Exploratory results, however, showed sclerostin negatively correlated with CVD risk and QoL. ClinicalTrials.gov #NCT0146469.

Hormones and Bone · Estrogen and Bone

DHEA in bone: the role in osteoporosis and fracture healing

Kirby DJ et al., 2020 Archives of osteoporosis

Dehydroepiandrosterone (DHEA) is a metabolic intermediate in the biosynthesis of estrogens and androgens with a past clouded in controversy and bold claims. It was once touted as a wonder drug, a fountain of youth that could cure all ailments. However, in the 1980s DHEA was banned by the FDA given a lack of documented health benefits and long-term use data. DHEA had a revival in 1994 when it was released for open market sale as a nutritional supplement under the Dietary Supplement Health and Safety Act. Since that time, there has been encouraging research on the hormone, including randomized controlled trials and subsequent meta-analyses on various conditions that DHEA may benefit. Bone health has been of particular interest, as many of the metabolites of DHEA are known to be involved in bone homeostasis, specifically estrogen and testosterone. Studies demonstrate a significant association between DHEA and increased bone mineral density, likely due to DHEA's ability to increase osteoblast activity and insulin like growth factor 1 (IGF-1) expression. Interestingly, IGF-1 is also known to improve fracture healing, though DHEA, a potent stimulator of IGF-1, has never been tested in this scenario. The aim of this review is to discuss the history and mechanisms of DHEA as they relate to the skeletal system, and to evaluate if DHEA has any role in treating fractures.

Bone Mineral Density · Peak Bone Mass

Low Bone Mineral Density in Elite Female Athletes With a History of Secondary Amenorrhea in Their Teens

Nose-Ogura S et al., 2020 Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine

To determine whether secondary amenorrhea during teenage years influences bone mineral density (BMD) in female athletes in their 20s. Original research. Japan Institute of Sports Sciences. Two hundred ten elite female athletes older than 20 years were included in the study. Information on the participants' past (ie, during their teenage years) and current menstrual cycle, training time, history of stress fractures, and blood tests for hormones received was obtained. Bone mineral density of the lumbar spine was evaluated by dual-energy x-ray absorptiometry; low BMD was defined as a Z-score ≤-1. We investigated the correlation factors for low BMD in athletes in their 20s by univariable and multivariable logistic regression analysis. A total of 39 (18.6%) female athletes had low BMD. Secondary amenorrhea in their teens [odds ratio (OR), 7.11, 95% confidence interval (CI), 2.38-21.24; P < 0.001] and present body mass index (BMI) (OR, 0.56, 95% CI, 0.42-0.73; P < 0.001) were independent correlation factors for low BMD in the multivariable logistic regression analysis. The average Z-score for those with secondary amenorrhea in their teens and 20s, secondary amenorrhea in their 20s only, and regular menstruation was -1.56 ± 1.00, -0.45 ± 1.21, and 0.82 ± 1.11 g/cm, respectively. Secondary amenorrhea for at least 1 year during teenage years in female athletes and BMI at present was strongly associated with low BMD in their 20s.

Bone Mineral Density · Measurement

Prolonged Amenorrhea and Low Hip Bone Mineral Density in Women Living With HIV-A Controlled Cross-sectional Study

King EM et al., 2020 J Acquir Immune Defic Syndr

Women living with HIV (WLWH) have higher rates of prolonged secondary amenorrhea (no flow for ≥1 year) than HIV-negative women. Both having amenorrhea and being HIV positive are associated with lower areal bone mineral density (BMD). However, their combined BMD effects remain unclear. Therefore, we investigated prolonged amenorrhea and BMD in WLWH and controls. This cross-sectional study enrolled WLWH and HIV-negative control women aged 19-68 years of similar backgrounds. We assessed BMD (Hologic; as ageand ethnicity-matched Z-scores) in the Children and women: AntiRetrovirals and Markers of Aging cohort. Participants were stratified by amenorrhea history defined as past/present lack of menses for ≥1 year at age 45 and younger and not because of surgery, breastfeeding, pregnancy, or hormonal contraception. Hip and spine Z-scores by amenorrhea/no amenorrhea used linear models with multivariable analysis for relationships within WLWH. WLWH (N = 129) were similar to controls (N = 129) in age, body mass index, ethnicity, and substance use. Among WLWH, 21% experienced prolonged amenorrhea vs. 9% in controls. WLWH had significantly lower total hip (mean ± SD: -0.4 ± 0.9 vs. 0.3 ± 1.1; P < 0.001) and spine (-0.5 ± 1.3 vs. 0.2 ± 1.3; P = 0.001) Z-scores than controls. Amenorrhea was independently associated with hip (P = 0.01) but not spine (P = 0.94) BMD by multivariable linear regression. WLWH with amenorrhea had lower hip Z-scores (-0.8 ± 0.9) than those without (-0.3 ± 0.8; P = 0.01). They also had higher rates of substance use, smoking, opioid therapy, hepatitis C coinfection, and lower CD4 nadir. WLWH had higher rates of prolonged amenorrhea and lower BMD than controls. WLWH with amenorrhea experienced lower hip BMD Z-scores than those without. Prolonged amenorrhea is an added osteoporosis risk in WLWH.

Fracture Risk · Risk Factors

Combining Frailty and Trabecular Bone Score Did Not Improve Predictive Accuracy in Risk of Major Osteoporotic Fractures

Li G et al., 2020 J Bone Miner Res

It is recognized that the trabecular bone score (TBS) provides skeletal information, and frailty measurement is significantly associated with increased risks of adverse health outcomes. Given the suboptimal predictive power in fracture risk assessment tools, we aimed to evaluate the combination of frailty and TBS regarding predictive accuracy for risk of major osteoporotic fracture (MOF). Data from the prospective longitudinal study of CaMos (Canadian Multicentre Osteoporosis Study) were used for this study. TBS values were estimated using lumbar spine (L1 to L4 ) dual-energy X-ray absorptiometry (DXA) images; frailty was evaluated by a frailty index (FI) of deficit accumulation. Outcome was time to first incident MOF during the follow-up. We used the Harrell's C-index to compare the model predictive accuracy. The Akaike information criterion, likelihood ratio test, and net reclassification improvement (NRI) were used to compare model performances between the model combining frailty and TBS (subsequently called "FI + TBS"), FI-alone, and TBS-alone models. We included 2730 participants (mean age 69 years; 70% women) for analyses (mean follow-up 7.5 years). There were 243 (8.90%) MOFs observed during follow-up. Participants with MOF had significantly higher FI (0.24 versus 0.20) and lower TBS (1.231 versus 1.285) than those without MOF. FI and TBS were significantly related with MOF risk in the model adjusted for FRAX with bone mineral density (BMD) and other covariates: hazard ratio (HR) = 1.26 (95% confidence interval [CI] 1.11-1.43) for per-SD increase in FI; HR = 1.38 (95% CI 1.21-1.59) for per-SD decrease in TBS; and these associations showed negligible attenuation (HR = 1.24 for per-SD increase in FI, and 1.35 for per-SD decrease in TBS) when combined in the same model. Although the model FI + TBS was a better fit to the data than FI-alone and TBS-alone, only minimal and nonsignificant enhancement of discrimination and NRI were observed in FI + TBS. To conclude, frailty and TBS are significantly and independently related to MOF risk. Larger studies are warranted to determine whether combining frailty and TBS can yield improved predictive accuracy for MOF risk.

Fracture Risk · Risk Factors

Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study

Papaioannou A et al., 2020 Osteoporos Int

We examined the underlying relationship between fracture risk factors and their imminent risk. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher imminent fracture risk. Past year falls indirectly predicted imminent risk through physical functioning and general health. This study aimed to examine direct and indirect effects of several factors on imminent (1 year) fracture risk. Data from women age 65 and older from population-based Canadian Multicentre Osteoporosis Study were used. Predictors were identified from study years 5 and 10, and imminent fracture data (1-year fracture) came from years 6 and 11 (year 5 predicts year 6, year 10 predicts year 11). A structural equation model (SEM) was used to test the theoretical construct. General health and physical functioning were measured as latent variables using items from the 36-Item Short Form Health Survey (SF-36) and bone mineral density (BMD) T-score was a latent variable based on observed site-specific BMD data (spine L1-L4, femoral neck, total hip). Observed variables were fractures and falls. Model fit was evaluated using root mean square error of approximation (RMSEA), Tucker Lewis index (TLI), and comparative fit index (CFI). The analysis included 3298 women. Model fit tests showed that the SEM fit the data well; χ2(172) = 1122.10 < .001, RMSEA = .03, TLI = .99, CFI = .99. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher risk of fracture in the subsequent year (p < .001). Past year falls had a statistically significant but indirect effect on imminent fracture risk through physical functioning and general health (p < .001). We found several direct and indirect pathways that predicted imminent fracture risk in elderly women. Future studies should extend this work by developing risk scoring methods and defining imminent risk thresholds.

Fracture Risk · Risk Factors

Vertebral Fractures in Individuals With Type 2 Diabetes: More Than Skeletal Complications Alone

Koromani F et al., 2019 Diabetes Care Open Access

We aimed to assess whether individuals with type 2 diabetes (T2D) have increased risk of vertebral fractures (VFs) and to estimate nonvertebral fracture and mortality risk among individuals with both prevalent T2D and VFs. A systematic PubMed search was performed to identify studies that investigated the relationship between T2D and VFs. Cohorts providing individual participant data (IPD) were also included. Estimates from published summary data and IPD cohorts were pooled in a random-effects meta-analysis. Multivariate Cox regression models were used to estimate nonvertebral fracture and mortality risk among individuals with T2D and VFs. Across 15 studies comprising 852,705 men and women, individuals with T2D had lower risk of prevalent (odds ratio [OR] 0.84 [95% CI 0.74-0.95]; I (2) = 0.0%; P (het) = 0.54) but increased risk of incident VFs (OR 1.35 [95% CI 1.27-1.44]; I (2) = 0.6%; P (het) = 0.43). In the IPD cohorts (N = 19,820), risk of nonvertebral fractures was higher in those with both T2D and VFs compared with those without T2D or VFs (hazard ratio [HR] 2.42 [95% CI 1.86-3.15]) or with VFs (HR 1.73 [95% CI 1.32-2.27]) or T2D (HR 1.94 [95% CI 1.46-2.59]) alone. Individuals with both T2D and VFs had increased mortality compared with individuals without T2D and VFs (HR 2.11 [95% CI 1.72-2.59]) or with VFs alone (HR 1.84 [95% CI 1.49-2.28]) and borderline increased compared with individuals with T2D alone (HR 1.23 [95% CI 0.99-1.52]). Based on our findings, individuals with T2D should be systematically assessed for presence of VFs, and, as in individuals without T2D, their presence constitutes an indication to start osteoporosis treatment for the prevention of future fractures.

Bone Mineral Density · Measurement

322. Prolonged Amenorrhea Is Associated with Decreased Hip Bone Mineral Density in Women Living with HIV

King EM et al., 2019 Open forum infectious diseases Open Access

Background Women living with HIV (WLWH) have higher rates of long-term amenorrhea (no flow for ≥12 months) than HIV-negative women. However, little is known about the consequences of amenorrhea for WLWH. Both amenorrhea and HIV are associated with lower areal bone mineral density (BMD); though the combined effect of both on BMD remains unclear. In this cross-sectional study we investigated whether prolonged amenorrhea adversely affects BMD among WLWH. Methods We investigated BMD (using a Hologic bone densitometer) and prolonged amenorrhea among WLWH and HIV-negative control women of similar socioeconomic backgrounds aged 19–68 in the CARMA cohort. Participants were stratified by HIV status and history of prolonged secondary amenorrhea defined as a self-reported absence of menses for at least one year in the past or present, occurring at age <45 years and not due to surgery, breastfeeding, pregnancy or hormonal contraception. Hip and spine Z-scores (ageand racestandardized BMD values) were compared between groups using linear models, followed by multivariable analysis of BMD-related factors. Results WLWH (N = 129) had significantly lower hip (mean±SD −0.4 ± 0.9 vs. 0.3 ± 1.1; P < 0.001) and spine (−0.5 ± 1.3 vs. 0.2 ± 1.3; P = 0.001) Z-scores vs. controls (N = 129). Multivariable linear regression found prolonged amenorrhea was independently related to lower hip (P = 0.01), but not spine (P = 0.94) BMD. Within WLWH, the effect of amenorrhea was also additive to that of HIV, with hip Z-scores of -0.8±0.9for those with amenorrhea vs. -0.3±0.8for those normally cycling (P = 0.01). Amongst WLWH, those with prolonged amenorrhea had higher rates of illicit substance use, smoking, chronic opioid therapy, hepatitis C viral infection, and poorer HIV viral control than those with normal menstruation. Conclusion These data suggest that WLWH having prolonged amenorrhea of ≥1 year’s duration are at increased risk for hip bone loss, a finding influenced by comorbid, HIV-associated conditions. Screening WLWH for menstrual history will allow early discovery of osteoporosis risk, and stimulate preventative measures to mitigate bone loss. Disclosures All authors: No reported disclosures.

Osteoporosis · Diagnosis and Treatment

Reduced Bone Loss Is Associated With Reduced Mortality Risk in Subjects Exposed to Nitrogen Bisphosphonates: A Mediation Analysis

Bliuc D et al., 2019 J Bone Miner Res

Bisphosphonates, potent antiresorptive agents, have been found to be associated with mortality reduction. Accelerated bone loss is, in itself, an independent predictor of mortality risk, but the relationship between bisphosphonates, bone loss, and mortality is unknown. This study aimed to determine whether the association between bisphosphonates and mortality is mediated by a reduction in the rate of bone loss. Participants from the population-based Canadian Multicentre Osteoporosis Study were followed prospectively between1996 and 2011. Comorbidities and lifestyle factors were collected at baseline and bone mineral density (BMD) at baseline and at years 3 (for those aged 40 to 60 years), 5, and 10. Rate of bone loss was calculated using linear regression. Information on medication use was obtained yearly. Bisphosphonate users grouped into nitrogen bisphosphonates (nBP; alendronate or risedronate) and etidronate and non-users (NoRx) were matched by propensity score, including all baseline factors as well as time of treatment. Cox's proportional hazards models, unadjusted and adjusted for annual rate of bone loss, were used to determine the association between nBP and etidronate versus NoRx. For the treatment groups with significant mortality risk reduction, the percent of mortality reduction mediated by a reduction in the rate of bone loss was estimated using a causal mediation analysis. There were 271 pairs of nBP and matched NoRx and 327 pairs of etidronate and matched NoRx. nBP but not etidronate use was associated with significant mortality risk reduction (hazard ratios [HR] = 0.61 [95% confidence interval 0.39-0.96] and 1.35 [95% CI 0.86-2.11] for nBP and etidronate, respectively). Rapid bone loss was associated with more than 2-fold increased mortality risk compared with no loss. Mediation analysis indicated that 39% (95% CI 7%-84%) of the nBP association with mortality was related to a reduction in the rate of bone loss. This finding provides an insight into the mechanism of the relationship between nBP and survival benefit in osteoporotic patients.

Fracture Risk · Risk Factors

Predictors of imminent non-vertebral fracture in elderly women with osteoporosis, low bone mass, or a history of fracture, based on data from the population-based Canadian Multicentre Osteoporosis Study (CaMos)

Adachi JD et al., 2019 Arch Osteoporos

Using data from the Canadian Multicentre Osteoporosis Study, several risk factors predictive of imminent (2-year) risk of low-trauma non-vertebral fracture among high-risk women were identified, including history of falls, history of low-trauma fracture, poorer physical function, and lower T score. Careful consideration should be given to targeting this population for therapy. Fracture risk assessment has focused on a long-term horizon and populations with a broad risk range. For elderly women with osteoporosis or low bone mass, or a history of fragility fractures ("high-risk women"), risk prediction over a shorter horizon may have greater clinical relevance. A repeated-observations design and data from the Canadian Multicentre Osteoporosis Study were employed. Study population comprised women aged ≥ 65 years with T score (total hip, femoral neck, spine) ≤ - 1.0 or prior fracture. Hazard ratios (HR) for predictors of low-trauma non-vertebral fracture during 2-year follow-up were estimated using multivariable shared frailty model. The study population included 3228 women who contributed 5004 observations; 4.8% experienced low-trauma non-vertebral fracture during the 2-year follow-up. In bivariate analyses, important risk factors included age, back pain, history of falls, history of low-trauma fracture, physical function, health status, and total hip T score. In multivariable analyses, only four independent predictors were identified: falls in past 12 months (≥ 2 falls: HR = 1.9; 1 fall: HR = 1.5), low-trauma fracture in past 12 months (≥ 1 fracture: HR = 1.7), SF-36 physical component summary score (≤ 42.0: HR = 1.6), and total hip T score (≤ - 3.5: HR = 3.7; > - 3.5 to ≤ - 2.5: HR = 2.5; > - 2.5 to ≤ - 1: HR = 1.3). Imminent risk of low-trauma non-vertebral fracture is elevated among high-risk women with a history of falls or low-trauma fracture, poorer physical function, and lower T score. Careful consideration should be given to identifying and targeting this population for therapy.

Osteoporosis · Diagnosis and Treatment

Longitudinal assessment of health-related quality of life in osteoporosis: data from the population-based Canadian Multicentre Osteoporosis Study

Hopman WM et al., 2019 Osteoporos Int

Little is known about the association between health-related quality of life (HRQOL) and osteoporosis in the absence of fracture, and how HRQOL may change over time. This study provides evidence of substantially reduced HRQOL in women and men with self-reported and/or BMD-confirmed osteoporosis, even in the absence of fragility fracture. Fragility fractures have a detrimental effect on the health-related quality of life (HRQOL) of those with osteoporosis. Less is known about the association between HRQOL and osteoporosis in the absence of fracture. Canadian Multicentre Osteoporosis Study participants completed the SF-36, a detailed health questionnaire and measures of bone mineral density (BMD) at baseline and follow-up. We report the results of participants ≥ 50 years with 10-year follow-up. Self-reported osteoporosis at baseline and BMD-based osteoporosis at follow-up were ascertained. Multivariable linear regression models were developed for baseline SF-36 domains, component summaries, and change over time, adjusting for relevant baseline information. Baseline data were available for 5266 women and 2112 men. Women in the osteoporosis group had substantially lower SF-36 baseline scores, particularly in the physically oriented domains, than those without osteoporosis. A similar but attenuated pattern was evident for the men. After 10-year follow-up (2797 women and 1023 men), most domain scores dropped for women and men regardless of osteoporosis status, with the exception of mentally-oriented ones. In general, a fragility fracture was associated with lower SF-36 scores and larger declines over time. This study provides evidence of substantially reduced HRQOL in women and men with self-reported and/or BMD-confirmed osteoporosis, even in the absence of fragility fracture. HRQOL should be thoroughly investigated even prior to fracture, to develop appropriate interventions for all stages of the disease.

Fracture Risk · Risk Factors

Parity and lactation are not associated with incident fragility fractures or radiographic vertebral fractures over 16 years of follow-up: Canadian Multicentre Osteoporosis Study (CaMos)

Cooke-Hubley S et al., 2019 Arch Osteoporos

Parity and lactation showed no associations with incident clinical fragility fractures or radiographic vertebral compression fractures in the 16-year CaMos prospective study. Parity was associated with slightly greater decline in femoral neck but not hip or spine areal bone mineral density (aBMD), while lactation showed no associations with aBMD change. Pregnancy and especially lactation cause loss of bone mass and microarchitectural changes, which temporarily increase fracture risk. After weaning, aBMD increases but skeletal microarchitecture may be incompletely restored. Most retrospective clinical studies found neutral or even protective associations of parity and lactation with fragility fractures, but prospective data are sparse. CaMos is a randomly selected observational cohort that includes ~ 6500 women followed prospectively for over 16 years. We determined whether parity or lactation were related to incident clinical fragility fractures over 16 years, radiographic (morphometric and morphologic) vertebral fractures over 10 years, and aBMD change (spine, total hip, and femoral neck) over 10 years. Parity and lactation duration were analyzed as continuous variables in predicting these outcomes using univariate and multivariate regression analyses. Three thousand four hundred thirty-seven women completed 16 years of follow-up for incident clinical fractures, 3839 completed 10 years of morphometric vertebral fracture assessment, 3788 completed 10 years of morphologic vertebral fracture assessment, and 4464 completed 10 years of follow-up for change in aBMD. In the multivariate analyses, parity and lactation duration showed no associations with clinical fragility fractures, radiographic vertebral fractures, or change in aBMD, except that parity associated with a probable chance finding of a slightly greater decline in femoral neck aBMD. Parity and lactation have no adverse associations with clinical fragility or radiographic vertebral fractures, or the rate of BMD decline over 10 years, in this prospective, multicenter study of a randomly selected, population-based cohort of women.

Osteoporosis · Diagnosis and Treatment

The Radiology of Osteoporotic Vertebral Fractures Revisited

Lentle B et al., 2019 J Bone Miner Res

Until recently there has been little evidence available to validate any method by which to make an accurate diagnosis of an osteoporotic vertebral fractures (OVFs) from plain radiographs. In part this reflects a lack of a completely satisfactory "gold standard," but primarily it relates to the absence of well-designed prospective studies in this context. Historically, OVFs were recognized by evidence of macroscopic structural failure in vertebrae using the criteria applied elsewhere in the skeleton. This comprised altered alignment, fragmentation, cortical disruptions, and breaks, among other changes. However, these morphological criteria were replaced by vertebral morphometry, referring to the use of quantitative or quasi-quantitative measurement tools for fracture diagnosis. Vertebral morphometry emerged as an understanding of and treatment for osteoporosis evolved, mainly in response to the need for expeditious assessments of large numbers of spine images for epidemiological and pharmaceutical purposes. Although most of the descriptions of such morphometric tools have stressed that they were not to be applied to clinical diagnosis with respect to individual patients, this constraint has been widely disregarded. Here we review the major attempts to develop a diagnostic strategy for OVF and describe their characteristics in adults and children. Recent evidence suggests that morphometric (quantitative; ie, based on measurement of dimensions and shape description) criteria are inferior to morphologic (qualitative; ie, based on structural integrity) vertebral damage assessment in identifying people with low bone density and at an increased risk of future fracture. Thus there is now an evidentiary basis for suggesting that morphological assessment is the preferred strategy for use in diagnosing OVF from radiographs.

Fracture Risk · Risk Factors

Frailty and Risk of Fractures in Patients With Type 2 Diabetes

Li G et al., 2019 Diabetes Care

We aimed to explore whether frailty was associated with fracture risk and whether frailty could modify the propensity of type 2 diabetes toward increased risk of fractures.Research design and methodsData were from a prospective cohort study. Our primary outcome was time to the first incident clinical fragility fracture; secondary outcomes included time to hip fracture and to clinical spine fracture. Frailty status was measured by a Frailty Index (FI) of deficit accumulation. The Cox model incorporating an interaction term (frailty × diabetes) was used for analyses. The analysis included 3,149 (70% women) participants; 138 (60% women) had diabetes. Higher bone mineral density and FI were observed in participants with diabetes compared with control subjects. A significant relationship between the FI and the risk of incident fragility fractures was found, with a hazard ratio (HR) of 1.02 (95% CI 1.01-1.03) and 1.19 (95% CI 1.10-1.33) for per-0.01 and per-0.10 FI increase, respectively. The interaction was also statistically significant (P = 0.018). The HR for per-0.1 increase in the FI was 1.33 for participants with diabetes and 1.19 for those without diabetes if combining the estimate for the FI itself with the estimate from the interaction term. No evidence of interaction between frailty and diabetes was found for risk of hip and clinical spine fractures. Participants with type 2 diabetes were significantly frailer than individuals without diabetes. Frailty increases the risk of fragility fracture and enhances the effect of diabetes on fragility fractures. Particular attention should be paid to diabetes as a risk factor for fragility fractures in those who are frail.

Bone Mineral Density · Peak Bone Mass

Adolescent use of combined hormonal contraception and peak bone mineral density accrual: A meta-analysis of international prospective controlled studies

Goshtasebi A et al., 2019 Clin Endocrinol (Oxf) Open Access

Many women use combined hormonal contraceptives (CHC) during adolescence during which they are accruing peak areal bone mineral density (BMD) that relates to lifetime fracture risk. To build BMD requires formation with which CHC-related exogenous oestrogen may interfere. We compared peak BMD accrual in adolescents using and not using CHC. We performed literature searches for prospective published peer-reviewed articles providing 12to 24-month BMD change in adolescent (12to 19-year-old) women using CHC vs CHC-unexposed control women. Meta-analyses used random-effects models to assess BMD change rate at lumbar spine (LS) and other sites in adolescent CHC users vs CHC nonusers. Literature searches yielded 84 publications of which nine were eligible. Adolescent-only data were sought from cohorts with wider age inclusions. The 12-month LS meta-analysis with eight paired comparisons in 1535 adolescents showed a weighted mean BMD difference of -0.02 (95% confidence interval [CI]: -0.05 to 0.00) g/cm(2) in CHC-exposed adolescents (P = 0.04). The 24-month LS meta-analysis with five paired comparisons in 885 adolescents showed a highly significant weighted mean BMD difference of -0.02 (95% CI: -0.03 to -0.01) g/cm(2) in CHC-exposed adolescents (P = 0.0006). Heterogeneities by I(2) were 96% and 85%, respectively. Insufficient data for other bone sites precluded quantitative analysis. Given that adolescent exposure to CHC appears to be increasing, this evidence for potential impairment of peak spinal BMD accrual is of concern and suggests a potential public health problem. Randomized controlled trial data are needed to determine CHC effects on adolescent bone health.

Osteoporosis · Diagnosis and Treatment

Vertebral Fractures and Morphometric Deformities

Lentle BC et al., 2018 J Bone Miner Res

To the Editor: We read with interest the editorial by Cummings and Eastell,1 A History of Pivotal Advances in Clinical Research in Bone and Mineral Diseases, published in a recent issue of the JBMR. In discussing such advances, they include spinal morphometry, and specifically refer to and illustrate the Genant semiquantitative (GSQ) paradigm,2 although also referring to the algorithm-based qualitative (ABQ) method3 of vertebral evaluation in the diagnosis of osteoporotic vertebral fractures (OVFs). Although in its day the GSQ method was a credible attempt at structured reporting, recent data suggest that GSQ grade 1 lesions, the most common, relate less well to bone density and fracture risk than comparable fractures diagnosed using the ABQ tool.4-6 Although morphometric methods may serve for understanding the epidemiology of osteoporotic fractures in large populations, it is much less certain that the GSQ method provides a basis for the care of individual patients. In a multidisciplinary context such as is served by this Journal, the endorsement of the GSQ method by the authors, without qualification, may well prove misleading. It is potentially invalid at the bedside and this should have been made explicit. We have observed a reluctance to give the presence of one or more vertebral fractures the importance they should be accorded because of confusion and ambiguity in the descriptive criteria and terminology used (eg, “wedging,” “deformity”) to define them. Perhaps the lack of a clear understanding of what might or might not constitute an OVF contributes to this disarray among radiologists and clinicians alike, again as noted recently by Szulc.7 Most of the many authors describing or reviewing “systems of morphometry,”8-12 such as in the current ASBMR primer,10 have cautioned that they are only to be used for epidemiological purposes. Moreover, most such reviews caution that positive findings should ideally be re-assessed by an “expert.” The danger, recognized by such constraints, is that of false-positive diagnoses from the clinical use of morphometry. In our experience, it is all too common for the iconic diagram provided by Dr. Genant to serve as a guide for the clinical evaluation of spinal images when that was not its intent. In the relevant article, Genant and colleagues2 were at pains to emphasize the importance of recognizing end-plate damage as evidence of OVF, but it has proved deceptively simple for readers to see only the diagram which Cummings and Eastell1 reproduce without noting these constraints. Historically the GSQ method was proposed as an attempt at structured diagnosis in fracture evaluation when such a concept was uncommon. Nevertheless it needs to be seen in perspective and it may have now outlived its usefulness. A great amount of admirable effort has gone into a structured understanding and diagnosis of atypical femoral fractures by the ASBMR.13 Those are, however, very rare events. Perhaps it is time to develop a comparable understanding of the much more common problem of OVF diagnosis to an extent the evidence allows. A taxonomy of such lesions is overdue. At present there are large differences in reported OVF incidence and prevalence for any given population. That fact probably reflects, at least in part, the method of diagnosis used, as much as any real insights into disease. None.

Bone Mineral Density · Measurement

Women's Mid-Life Night Sweats and 2-Year Bone Mineral Density Changes: A Prospective, Observational Population-Based Investigation from the Canadian Multicentre Osteoporosis Study (CaMos)

Wong EMM et al., 2018 Int J Environ Res Public Health Open Access

Women's hot flushes and night sweats, collectively called vasomotor symptoms (VMS), are maximal (79%) in late perimenopause. The evidence describing whether VMS are associated with loss of areal bone mineral density (BMD) is mixed. We examined baseline and 2-year data for 1570 randomly selected women aged 43⁻63 in the Canadian Multicentre Osteoporosis Study (CaMos), a prospective Canada-wide study; we used linear regression to assess the relationship of night sweats (VMSn) with BMD and its changes. Clinically important VMSn occurred for 12.2%. Women with VMSn were slightly younger (54.5 vs. 55.3 years, p = 0.02) and less likely to use sex steroid therapies (39.8% vs. 51.4%, p < 0.05). BMD at the lumbar spine (L1-4), femoral neck (FN) and total hip (TH) were similar between those with/without VMSn. In adjusted models, we did not find a significant association between VMSn and 2-year change in L1-4, FN and TH BMD. Age, reproductive status, weight, sex steroid therapy and smoking status were associated with 2-year change in BMD. Incident fractures over 2 years also did not differ by VMSn. Our analyses were restricted to VMSn and may not truly capture the relationship between VMS and BMD. Additional research involving VMS, bone loss and fracture incidence is needed.

Bone Mineral Density · Peak Bone Mass

Combined hormonal contraceptives use and bone mineral density changes in adolescent and young women in a prospective population-based Canada-wide observational study

Brajic TS et al., 2018 J Musculoskelet Neuronal Interact

To assess combined hormonal contraceptives (CHC) use and adolescent women's peak areal bone mineral density (BMD) accrual. We enrolled 527 randomly selected women across Canada (2004-6) divided by age into adolescents (16-19) and young adults (20-24) and by CHC use to ever (E-CHC)/never (N-CHC) users. At baseline and year 2 we measured height, weight, and BMD at lumbar spine (L1-4), femoral neck, and total hip sites. Interviewer-administered questionnaires addressed menarche age, cigarette and alcohol use, calcium/vitamin D intakes, physical activity and estrogen dose (≤30/>30 micrograms). Linear regression models examined associations of CHC use with 2-year BMD change adjusted for bone-related variables. Of 307 women with complete data, 229 (75%) used CHC. N-CHC adolescents gained significantly more unadjusted total hip BMD +0.012 g/cm(2)/2-y (95% C.I.: 0.001, 0.023) with similar trends at all sites. N-CHC adolescents tended to have greater adjusted femoral neck BMD gain: mean difference +0.009 g/cm(2) (95% CI: -0.002; 0.021). In young women N-CHC, however, adjusted femoral neck BMD decreased significantly more -0.021 g/cm(2) (95%CI: -0.006; -0.036) with similar trends at other sites. BMD changes were unrelated to estrogen dose and age at starting CHC. Adolescent CHC users in a random population demonstrated less hip region peak BMD accrual than non-users. This requires randomized control trial confirmation.

Hormones and Bone · Estrogen and Bone

Adult Premenopausal Bone Health Related to Reproductive Characteristics-Population-Based Data from the Canadian Multicentre Osteoporosis Study (CaMos)

Goshtasebi A et al., 2018 Int J Environ Res Public Health Open Access

Amenorrhea is important for women's bone health. However, few have reported reproductive, anthropometric (body mass index [BMI], height) and bone health (areal bone mineral density [BMD], prevalent fractures) in a population-based study. The purposes of this cross-sectional study of women in the randomly-selected Canadian Multicentre Osteoporosis Study (CaMos) population were: (1) to describe reproductive, demographic, anthropometric and lifestyle variables; and (2) in menstruating women, to relate reproductive and other variables to BMD at the lumbar spine (L1-4, LS), femoral neck (FN) and total hip (TH) sites and to prevalent fragility fractures. This study describes the reproductive characteristics of 1532 women aged 30⁻60 years. BMD relationships with reproductive and other variables were described in the 499 menstruating women. Mean menarche age was 12.8 years, 96% of women were parous and 95% had used combined hormonal contraceptives (CHC). Infertility was reported by 9%, androgen excess by 13%, amenorrhea by 8% and nulliparity by 4%. LS BMD was negatively associated with amenorrhea and androgen excess and positively related to current BMI and height. A later age at menarche negatively related to FN BMD. BMI and height were strongly related to BMD at all sites. Prevalent fragility fractures were significantly associated with quartiles of both LS and TH BMD.

Bone Mineral Density · Measurement

Premature Spinal Bone Loss in Women Living with HIV is Associated with Shorter Leukocyte Telomere Length

Kalyan S et al., 2018 Int J Environ Res Public Health Open Access

With advances in combination antiretroviral therapy (cART), people living with HIV are now surviving to experience aging. Evidence suggests that individuals living with HIV are at greater risk for low bone mineral density (BMD), osteoporosis, and fractures. Better understanding of the pathophysiology of bone health in women living with HIV (WLWH) is important for treatment strategies. The goal of this study was to explore new biological factors linked to low BMD in WLWH. Standardized BMD measures of WLWH were compared to reference values from an unselected population of women from the same geographical region of the same age range. Linear regression analysis was used to assess relationships among health-related characteristics, cellular aging (measured by leukocyte telomere length; LTL), cART, and BMD of WLWH. WLWH (n = 73; mean age 43 ± 9 years) had lower BMD Z-scores at the lumbar spine (LS) (mean difference = -0.39, p p = 0.012) relative to controls (n = 290). WLWH between 50 and 60 years (n = 17) had lower Z-scores at the LS (p = 0.008) and TH (p = 0.027) compared to controls (n = 167). Among WLWH, LS BMD was significantly associated with LTL (R² = 0.09, p = 0.009) and BMI (R² = 0.06, p = 0.042). Spinal BMD was adversely affected in WLWH. Reduction of LTL was strongly associated with lower BMD and may relate to its pathophysiology and premature aging in WLWH.

Osteoporosis · Diagnosis and Treatment

Osteopenia and Osteoporosis in Female Athletes

MacKnight JM, 2017 Clinics in sports medicine

Disorders of bone density are especially prevalent among athletic women. The severity of bone loss ranges from osteopenia to frank osteoporosis. In female athletes, a higher incidence of osteoporosis is due to a decreased rate of bone accretion in youth, often as a result of hormonal deficiency and/or excessive exercise. Low bone mass poses a particular challenge for athletes because it predisposes to stress-related bone injuries and increases the risk of osteoporosis and insufficiency fractures with aging. This article reviews the pathophysiology of bone thinning in premenopausal and postmenopausal women, the impact of exercise, and the treatment options presently available.

Hormones and Bone · Estrogen and Bone

Estrogen-progestin therapy causes a greater increase in spinal bone mineral density than estrogen therapy - a systematic review and meta-analysis of controlled trials with direct randomization

Prior JC et al., 2017 J Musculoskelet Neuronal Interact

To assess whether progesterone (P4) or osteoblast P4 receptor-acting progestin (P) contributed to estrogen (E) therapy-related increased areal bone mineral density (BMD) in randomized controlled trials (RCT) with direct randomization to estrogen (ET) or estrogen-progestin (EPT) therapy. Systematic literature searches in biomedical databases identified RCT with direct randomization and parallel estrogen doses that measured spinal BMD change/year. Cyclic P4/P was included in this random effects meta-analysis only if for ≥ half the number of E-days. Searches yielded 155 publications; five met inclusion criteria providing eight dose-parallel ET-EPT comparisons in 1058 women. Women averaged mid-50 years, ⟨five years into menopause and took conjugated equine E daily at 0.625 mg with/without 2.5 mg medroxyprogesterone acetate (MPA). The weighted mean EPT minus ET percentage difference in spinal BMD change was +0.68%/year (95% CI 0.38, 0.97%) (P=0.00001). This result was highly heterogeneous (I²=81%) but this may reflect the small number of studies. Estrogen with an osteoblast P4R-acting progestin (EPT) in these five published RCT provides Level 1 evidence that MPA caused significantly greater annual percent spinal BMD gains than the same dose of ET. These data have implications for management of vasomotor symptoms and potentially for osteoporosis treatment in menopausal women.

Osteoporosis · Diagnosis and Treatment

Comparative Analysis of the Radiology of Osteoporotic Vertebral Fractures in Women and Men: Cross-Sectional and Longitudinal Observations from the Canadian Multicentre Osteoporosis Study (CaMos)

Lentle BC et al., 2017 J Bone Miner Res

We compared two methods for osteoporotic vertebral fracture (VF) assessment on lateral spine radiographs, the Genant semiquantitative (GSQ) technique and a modified algorithm-based qualitative (mABQ) approach. We evaluated 4465 women and 1771 men aged ≥50 years from the Canadian Multicentre Osteoporosis Study with available X-ray images at baseline. Observer agreement was lowest for grade 1 VFs determined by GSQ. Among physician readers, agreement was greater for VFs diagnosed by mABQ (ranging from 0.62 [95% confidence interval (CI) 0.00-1.00] to 0.88 [0.76-1.00]) than by GSQ (ranging from 0.38 [0.17-0.60] to 0.69 [0.54-0.85]). GSQ VF prevalence (16.4% [95% CI 15.4-17.4]) and incidence (10.2/1000 person-years [9.2; 11.2]) were higher than with the mABQ method (prevalence 6.7% [6.1-7.4] and incidence 6.3/1000 person-years [5.5-7.1]). Women had more prevalent and incident VFs relative to men as defined by mABQ but not as defined by GSQ. Prevalent GSQ VFs were predominantly found in the mid-thoracic spine, whereas prevalent mABQ and incident VFs by both methods co-localized to the junction of the thoracic and lumbar spine. Prevalent mABQ VFs compared with GSQ VFs were more highly associated with reduced adjusted L(1) to L(4) bone mineral density (BMD) (-0.065 g/cm(2) [-0.087 to -0.042]), femoral neck BMD (-0.051 g/cm(2) [-0.065 to -0.036]), and total hip BMD (-0.059 g/cm(2) [-0.076 to -0.041]). Prevalent mABQ VFs compared with prevalent GSQ were also more highly associated with incident VF by GSQ (odds ratio [OR] = 3.3 [2.2-5.0]), incident VF by mABQ (9.0 [5.3-15.3]), and incident non-vertebral major osteoporotic fractures (1.9 [1.2-3.0]). Grade 1 mABQ VFs, but not grade 1 GSQ VFs, were associated with incident non-vertebral major osteoporotic fractures (OR = 3.0 [1.4-6.5]). We conclude that defining VF by mABQ is preferred to the use of GSQ for clinical assessments.

Bone Mineral Density · Measurement

Competing Factors Link to Bone Health in Polycystic Ovary Syndrome: Chronic Low-Grade Inflammation Takes a Toll

Kalyan S et al., 2017 Sci Rep Open Access

Chronic inflammation predisposes to poor bone health. Women with polycystic ovary syndrome (PCOS) experience androgen excess, ovulatory disturbances, insulin resistance, abdominal adiposity and chronic inflammation. Our objective was to investigate the relationships among bone health parameters, chronic subclinical inflammation and anthropometric measures in premenopausal women with and without PCOS. In 61 premenopausal women, 22 women with PCOS and 39 controls, we assessed bone parameters (total hip bone mineral density [BMD] by dual-energy X-ray absorptiometry and radius strength-strain index [SSI] by peripheral quantitative computed tomography), inflammation (C-reactive protein/albumin), oxidative stress (leukocyte telomere length, urinary 8-hydroxydeoxyguanosine); hemoglobin A1c; anthropometric measures (body mass index, waist-to-height ratio, cross-sectional muscle area). A diagnosis of PCOS negatively predicted (beta = -0.251, p = 0.022) hip BMD in a regression model including weight. In women with PCOS, inflammation, which was predicted by increased waist-to-height ratio and current use of oral contraceptives, attenuated the positive influences of increased weight and muscle mass on bone strength and was inversely associated with radial SSI (R(2) = 0.25, p = 0.018). In conclusion, chronic subclinical inflammation may negatively impact bone physiology in women with PCOS. Strategies focused on reducing abdominal adiposity and avoiding medications that increase inflammation may counter this effect.

Fracture Risk · Risk Factors

Population-Wide Impact of Non-Hip Non-Vertebral Fractures on Mortality

Tran T et al., 2017 J Bone Miner Res

Data on long-term consequences of non-hip non-vertebral (NHNV) fractures, accounting for approximately two-thirds of all fragility fractures, are scanty. Our study aimed to quantify the population-wide impact of NHNV fractures on mortality. The national population-based prospective cohort study (Canadian Multicentre Osteoporosis Study) included 5526 community dwelling women and 2163 men aged 50 years or older followed from July 1995 to September 2013. Population impact number was used to quantify the average number of people for whom one death would be attributable to fracture and case impact number to quantify the number of deaths out of which one would be attributable to a fracture. There were 1370 fragility fractures followed by 296 deaths in women (mortality rate: 3.49; 95% CI, 3.11 to 3.91), and 302 fractures with 92 deaths in men (5.05; 95% CI, 4.12 to 6.20). NHNV fractures accounted for three-quarters of fractures. In women, the population-wide impact of NHNV fractures on mortality was greater than that of hip and vertebral fractures because of the greater number of NHNV fractures. Out of 800 women, one death was estimated to be attributable to a NHNV fracture, compared with one death in 2000 women attributable to hip or vertebral fracture. Similarly, out of 15 deaths in women, one was estimated to be attributable to a NHNV fracture, compared with one in over 40 deaths for hip or vertebral fracture. The impact of forearm fractures (ie, one death in 2400 women and one out of 42 deaths in women attributable to forearm fracture) was similar to that of hip, vertebral, or rib fractures. Similar, albeit not significant, results were noted for men. The study highlights the important contribution of NHNV fractures on mortality because many NHNV fracture types, except for the most distal fractures, have serious adverse consequences that affect a significant proportion of the population.

Bone Mineral Density · Measurement

Densitometer-Specific Differences in the Correlation Between Body Mass Index and Lumbar Spine Trabecular Bone Score

Mazzetti G et al., 2017 J Clin Densitom

Trabecular bone score (TBS) is a gray-level texture measure derived from lumbar spine dual-energy X-ray absorptiometry (DXA) images that predicts fractures independent of bone mineral density (BMD). Increased abdominal soft tissue in individuals with elevated body mass index (BMI) absorbs more X-rays during image acquisition for BMD measurement and must be accommodated by the TBS algorithm. We aimed to determine if the relationship between BMI and TBS varied between 2 major manufacturers' densitometers, because different densitometers accommodate soft tissues differently. We identified 1919 women and 811 men, participants of the Canadian Multicentre Osteoporosis Study, aged ≥40 yr with lumbar spine DXA scans acquired on GE Lunar (4 centers) or Hologic (3 centers) densitometers at year 10 of follow-up. TBS was calculated for L1-L4 (TBS iNsight® software, version 2.1). A significant negative correlation between TBS and BMI was observed when TBS measurements were performed on Hologic densitometers in men (Pearson r = -0.36, p <0.0001) and in women (Pearson r = -0.33, p <0.0001); significant correlations were not seen when TBS was measured on GE Lunar densitometers (Pearson r = 0.00 in men, Pearson r = -0.02 in women). Age-adjusted linear regression models confirmed significant interactions between BMI and densitometer manufacturer for both men and women (p < 0.0001). In contrast, comparable positive correlations were observed between BMD and BMI on both Hologic and GE Lunar densitometers in men and women. In conclusion, BMI significantly affects TBS values in men and women when measured on Hologic but not GE Lunar densitometers. This finding has implications for clinical and research applications of TBS, especially when TBS is measured sequentially on DXA densitometers from different manufacturers or when results from different machines are pooled for analysis.

Osteoporosis · Diagnosis and Treatment

Premenopausal Osteoporosis

Cohen A, 2017 Endocrinol Metab Clin North Am Open Access

Most premenopausal women with low trauma fracture(s) or low bone mineral density have a secondary cause of osteoporosis or bone loss. Where possible, treatment of the underlying cause should be the focus of management. Premenopausal women with an ongoing cause of bone loss and those who have had, or continue to have, low trauma fractures may require pharmacologic intervention. Clinical trials provide evidence of benefits of bisphosphonates and teriparatide for bone mineral density in several types of premenopausal osteoporosis, but studies are small and do not provide evidence regarding fracture risk reduction.

Fracture Risk · Risk Factors

The impact of depot medroxyprogesterone acetate on fracture risk: a case-control study from the UK

Kyvernitakis I et al., 2017 Osteoporos Int

There has been concerning about women receiving depot medroxyprogesterone acetate (DMPA) contraception because of the prolonged hypoestrogenemic state regarding the potential negative effects on bone health. This study showed that DMPA exposure is associated with increased fracture risk and that fracture risk increases with longer DMPA exposure. DMPA has been associated with impaired bone mineral acquisition during adolescence and accelerated bone loss in later life. We performed this large population-based study to assess the association between use of DMPA or combined oral contraceptives and the incident risk of fracture. We identified 4189 women between 20 and 44 years of age with a first-time fracture diagnosis, matched them with 4189 random controls using the Disease Analyzer database and investigated the relation with DMPA exposure. Overall, 11 % of the fracture cases and 7.7 % of the controls had DMPA use recorded. The adjusted OR for developing a fracture in patients with current use of DMPA compared to non-users was 0.97 (95 % CI 0.51-1.86), 2.41 (95 % CI 1.42-4.08), and 1.46 (95 % CI 0.96-2.23) for 1-2, 3-9, and ≥10 prescriptions, respectively. The adjusted OR for developing a fracture in patients with past use of DMPA compared to non-users was 0.96 (95 % CI 0.73-1.26), 1.14 (95 % CI 0.86-1.51), and 1.55 (95 % CI 1.07-2.27) for 1-2, 3-9, and ≥10 prescriptions, respectively. The highest fracture risk was identified in young patients less than 30 years with longer DMPA exposure (≥10 prescriptions; OR 3.04, 95 % CI 1.36-6.81), as well as in patients in the late reproductive years with past use of DMPA (OR 1.72, 95 % CI 1.13-2.63). Our results indicate that DMPA exposure is associated with increased fracture risk and may have negative effects on bone metabolism, resulting in impaired bone mineral acquisition during adolescence and accelerated bone loss in adult life.

Fracture Risk · Risk Factors

Trabecular Bone Score and Incident Fragility Fracture Risk in Adults with Reduced Kidney Function

Naylor KL et al., 2016 Clin J Am Soc Nephrol Open Access

Background and Trabecular bone score is a gray-level textural measure obtained from dual energy x-ray absorptiometry lumbar spine images that provides information independent of areal bone mineral density. The association between trabecular bone score and incident fractures in adults with reduced kidney function and whether this association differs from that of adults with normal kidney function are unknown. DESIGN, SETTING, PARTICIPANTS, & We included 1426 participants ages ≥40 years old (mean age of 67 years) in the community-based Canadian Multicentre Osteoporosis Study. We stratified participants at cohort entry (2005-2008) by eGFR (eGFR<60 ml/min per 1.73 m2 [n=199; 72.4% stage 3a, 25.1% stage 3b, and 2.5% stage 4] versus ≥60 ml/min per 1.73 m2 [n=1227]). Trabecular bone score was obtained from lumbar spine (L1-L4) dual energy x-ray absorptiometry images, with a lower trabecular bone score representing worse bone structure. Over an average of 4.7 years follow-up (maximum follow-up of 5 years), we documented incident fragility (low-trauma) fracture events (excluding craniofacial, foot, and hand sites). We used a modified Kaplan-Meier estimator to determine the 5-year probability of fracture. Cox proportional hazard regression per SD lower trabecular bone score expressed the gradient of fracture risk. Individuals with an eGFR<60 ml/min per 1.73 m2 who had a trabecular bone score value below the median (<1.277) had a significantly higher 5-year fracture probability than those above the median (18.1% versus 6.2%; P=0.01). The association between trabecular bone score and fracture was independent of bone mineral density and other clinical risk factors in adults with reduced and normal kidney function (adjusted hazard ratio per SD lower trabecular bone score: eGFR<60 ml/min per 1.73 m2: adjusted hazard ratio, 1.62; 95% confidence interval, 1.04 to 2.51; eGFR≥60 ml/min per 1.73 m2: adjusted hazard ratio, 1.44; 95% confidence interval, 1.13 to 1.83). Lower lumbar spine trabecular bone score is independently associated with a higher fracture risk in adults with reduced kidney function. Additional study is needed to examine the association between trabecular bone score and fractures in individuals with diagnosed CKD-mineral and bone disorder.

Bone Mineral Density · Measurement

Premenopausal Trabecular Bone Loss is Associated with a Family History of Fragility Fracture

Prior JC et al., 2016 Geburtshilfe Frauenheilkd Open Access

Although a fragility fracture family history (FFFH+) has repeatedly been shown to be associated with lower bone mineral density (BMD), its relationship to human BMD change is unclear. Animal research, however, documented that different purebred strains within rodent species have wide ranges in rates of bone acquisition during growth as well as in change post-ovariectomy. Our objective was to compare the rate of premenopausal spinal trabecular BMD change between women with and without a general family history of fragility fracture. Participants and methodsHealthy premenopausal community women participated in prospective observational studies at two academic medical research centres: Vancouver, Canada (n = 66) and Munich, Germany (n = 20). The primary outcome was annual spinal BMD change, measured by quantitative computed tomography (QCT). The two studies employed similar methodologies for assessing QCT and FFFH. Volunteer community participants had a mean age of 36.0 (SD, 6.9) years, body mass index 22.5 (2.4) and baseline QCT of 150.2 (22.5) mg/cm3 trabecular bone. The rates of BMD change were similar in both cities: - 3.5 (5.1)/year Vancouver, - 2.0 (3.4)/year Munich (95 % CI of difference: - 3.9, 0.9). Over a third of the women (31 of the 86, 36 %) reported FFFH+. Those with and without a FFFH were similar in demographics, nutrition, exercise, menstrual cycle and luteal phase lengths and physiological measures (serum calcium, osteocalcin and estradiol). However, women with FFFH+ lost trabecular BMD more rapidly: FFFH+, - 4.9 (5.0), FFFH-, - 2.2 (4.4) mg/cm3/year (95 % CI diff - 0.7 to - 4.8, F1.83 = 7.88, p = 0.006). FFFH+ explained 7.7 % of the variance in QCT volumetric trabecular spinal bone change/year in these healthy premenopausal women. This study shows for the first time that having a history of a fragility fracture in a family member is associated with a greater rate of premenopausal spinal trabecular bone loss.

Bone Mineral Density · Peak Bone Mass

Associations of Protein Intake and Protein Source with Bone Mineral Density and Fracture Risk: A Population-Based Cohort Study

Langsetmo L et al., 2015 J Nutr Health Aging

High dietary protein has been hypothesized to cause lower bone mineral density (BMD) and greater fracture risk. Previous results are conflicting and few studies have assessed potential differences related to differing protein sources. To determine associations between total protein intake, and protein intake by source (dairy, non-dairy animal, plant) with BMD, BMD change, and incident osteoporotic fracture. DESIGN/Setting: Prospective cohort study (Canadian Multicentre Osteoporosis Study). Participants/Measures: Protein intake was assessed as percent of total energy intake (TEI) at Year 2 (1997-99) using a food frequency questionnaire (N=6510). Participants were contacted annually to ascertain incident fracture. Total hip and lumbar spine BMD was measured at baseline and Year 5. Analyses were stratified by group (men 25-49 y, men 50+ y, premenopausal women 25-49 y, and postmenopausal women 50+ y) and adjusted for major confounders. Fracture analyses were limited to those 50+ y. Intakes of dairy protein (with adjustment for BMI) were positively associated with total hip BMD among men and women aged 50+ y, and in men aged 25-49. Among adults aged 50+ y, those with protein intakes of <12% TEI (women) and <11% TEI (men) had increased fracture risk compared to those with intakes of 15% TEI. Fracture risk did not significantly change as intake increased above 15% TEI, and was not significantly associated with protein source. In contrast to hypothesized risk of high protein, we found that for adults 50+ y, low protein intake (below 15% TEI) may lead to increased fracture risk. Source of protein was a determinant of BMD, but not fracture risk.

Hormones and Bone · Estrogen and Bone

Nothing Boring About Boron

Pizzorno L, 2015 Integrative medicine (Encinitas, Calif.)

The trace mineral boron is a micronutrient with diverse and vitally important roles in metabolism that render it necessary for plant, animal, and human health, and as recent research suggests, possibly for the evolution of life on Earth. As the current article shows, boron has been proven to be an important trace mineral because it (1) is essential for the growth and maintenance of bone; (2) greatly improves wound healing; (3) beneficially impacts the body's use of estrogen, testosterone, and vitamin D; (4) boosts magnesium absorption; (5) reduces levels of inflammatory biomarkers, such as high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor α (TNF-α); (6) raises levels of antioxidant enzymes, such as superoxide dismutase (SOD), catalase, and glutathione peroxidase; (7) protects against pesticide-induced oxidative stress and heavy-metal toxicity; (8) improves the brains electrical activity, cognitive performance, and short-term memory for elders; (9) influences the formation and activity of key biomolecules, such as S-adenosyl methionine (SAM-e) and nicotinamide adenine dinucleotide (NAD(+)); (10) has demonstrated preventive and therapeutic effects in a number of cancers, such as prostate, cervical, and lung cancers, and multiple and non-Hodgkin's lymphoma; and (11) may help ameliorate the adverse effects of traditional chemotherapeutic agents. In none of the numerous studies conducted to date, however, do boron's beneficial effects appear at intakes > 3 mg/d. No estimated average requirements (EARs) or dietary reference intakes (DRIs) have been set for boron-only an upper intake level (UL) of 20 mg/d for individuals aged ≥ 18 y. The absence of studies showing harm in conjunction with the substantial number of articles showing benefits support the consideration of boron supplementation of 3 mg/d for any individual who is consuming a diet lacking in fruits and vegetables or who is at risk for or has osteopenia; osteoporosis; osteoarthritis (OA); or breast, prostate, or lung cancer.

Fracture Risk · Risk Factors

Steroidal contraceptives and bone fractures in women: evidence from observational studies

Lopez LM et al., 2015 Cochrane Database Syst Rev Open Access

Age-related decline in bone mass increases the risk of skeletal fractures, especially those of the hip, spine, and wrist. Steroidal contraceptives have been associated with changes in bone mineral density in women. Whether such changes affect the risk of fractures later in life is unclear. Hormonal contraceptives are among the most effective and most widely-used contraceptives. Concern about fractures may limit the use of these effective contraceptives. Observational studies can collect data on premenopausal contraceptive use as well as fracture incidence later in life. We systematically reviewed the evidence from observational studies of hormonal contraceptive use for contraception and the risk of fracture in women. Through June 2015, we searched for observational studies. The databases included PubMed, POPLINE, Cochrane Central Register of Controlled Trials (CENTRAL), LILACS, EMBASE, CINAHL, and Web of Science. We also searched for recent clinical trials through ClinicalTrials.gov and the ICTRP. For other studies, we examined reference lists of relevant articles and wrote to investigators for additional reports. Selection Criteria: We included cohort and case-control studies of hormonal contraceptive use. Interventions included comparisons of a hormonal contraceptive with a non-hormonal contraceptive, no contraceptive, or another hormonal contraceptive. The primary outcome was the risk of fracture. Data Collection and Analysis: Two authors independently extracted the data. One author entered the data into RevMan, and a second author verified accuracy. We examined the quality of evidence using the Newcastle-Ottawa Quality Assessment Scale (NOS), developed for case-control and cohort studies. Sensitivity analysis included studies of moderate or high quality based on our assessment with the NOS.Given the need to control for confounding factors in observational studies, we used adjusted estimates from the models as reported by the authors. Where we did not have adjusted analyses, we calculated the odds ratio (OR) with 95% confidence interval (CI). Due to varied study designs, we did not conduct meta-analysis. MAIN We included 14 studies (7 case-control and 7 cohort studies). These examined oral contraceptives (OCs), depot medroxyprogesterone acetate (DMPA), and the hormonal intrauterine device (IUD). This section focuses on the sensitivity analysis with six studies that provided moderate or high quality evidence.All six studies examined oral contraceptive use. We noted few associations with fracture risk. One cohort study reported OC ever-users had increased risk for all fractures (RR 1.20, 95% CI 1.08 to 1.34). However, a case-control study with later data from a subset reported no association except for those with 10 years or more since use (OR 1.55, 95% CI 1.03 to 2.33). Another case-control study reported increased risk only for those who had 10 or more prescriptions (OR 1.09, 95% CI 1.03 to 1.16). A cohort study of postmenopausal women found no increased fracture risk for OC use after excluding women with prior fracture. Two other studies found little evidence of association between OC use and fracture risk. A cohort study noted increased risk for subgroups, such as those with longer use or specific intervals since use. A case-control study reported increased risk for any fracture only among young women with less than average use.Two case-control studies also examined progestin-only contraceptives. One reported increased fracture risk for DMPA ever-use (OR 1.44, 95% CI 1.01 to 2.06), more than four years of use (OR 2.16, 95% CI 1.32 to 3.53), and women over 50 years old. The other reported increased risk for any past use, including one or two prescriptions (OR 1.17, 95% CI 1.07 to 1.29) and for current use of 3 to 9 prescriptions (OR 1.36, 95% CI 1.15 to 1.60) or 10 or more (OR 1.54, 95% CI 1.33 to 1.78). For the levonorgestrel-releasing IUD, one study reported reduced fracture risk for ever-use (OR 0.75, 95% CI 0.64 to 0.87) and for longer use. AUTHORS' Observational studies do not indicate an overall association between oral contraceptive use and fracture risk. Some reported increased risk for specific user subgroups. DMPA users may have an increased fracture risk. One study indicated hormonal IUD use may be associated with decreased risk. Observational studies need adjusted analysis because the comparison groups usually differ. Investigators should be clear about the variables examined in multivariate analysis.

Fracture Risk · Risk Factors

Ten-year incident osteoporosis-related fractures in the population-based Canadian Multicentre Osteoporosis Study - comparing site and age-specific risks in women and men

Prior JC et al., 2015 Bone Open Access

Population-based incident fracture data aid fracture prevention and therapy decisions. Our purpose was to describe 10-year site-specific cumulative fracture incidence by sex, age at baseline, and degree of trauma with/without consideration of competing mortality in the Canadian Multicentre Osteoporosis Study adult cohort. Incident fractures and mortality were identified by annual postal questionnaires to the participant or proxy respondent. Date, site and circumstance of fracture were gathered from structured interviews and medical records. Fracture analyses were stratified by sex and age at baseline and used both Kaplan-Meier and competing mortality methods. The baseline (1995-97) cohort included 6314 women and 2789 men (aged 25-84 years; mean±SD 62±12 and 59±14, respectively), with 4322 (68%) women and 1732 (62%) men followed to year-10. At least one incident fracture occurred for 930 women (14%) and 247 men (9%). Competing mortality exceeded fracture risk for men aged 65+years at baseline. Age was a strong predictor of incident fractures especially fragility fractures, with higher age gradients for women vs. men. Major osteoporotic fracture (MOF) (hip, clinical spine, forearm, humerus) accounted for 41-74% of fracture risk by sex/age strata; in women all MOF sites showed age-related increases but in men only hip was clearly age-related. The most common fractures were the forearm for women and the ribs for men. Hip fracture incidence was the highest for the 75-84 year baseline age-group with no significant difference between women 7.0% (95% CI 5.3, 8.9) and men 7.0% (95% CI 4.4, 10.3). Interpretation: There are sex differences in the predominant sites and age-gradients of fracture. In older men, competing mortality exceeds cumulative fracture risk.

Hormones and Bone · Estrogen and Bone

Characteristics of hyperparathyroid states in the Canadian multicentre osteoporosis study (CaMos) and relationship to skeletal markers

Berger C et al., 2014 Clin Endocrinol (Oxf)

PTH is an essential regulator of mineral metabolism; PTH hypersecretion may result in hyperparathyroidism including normocalcaemic, primary and secondary hyperparathyroidism. To examine the characteristics of participants with hyperparathyroid states and the relationship to bone mineral density (BMD). A cross-sectional study of 1872 community-dwelling men and women aged 35+ years (mostly Caucasian) with available serum PTH from Year 10 Canadian Multicentre Osteoporosis Study follow-up (2005-07). PTH was determined using a second-generation chemiluminescence immunoassay. L1-L4, femoral neck and total hip BMD. We established a PTH reference range (2·7-10·2 pmol/l) based on healthy participants (i.e. normal serum calcium, serum 25-hydroxyvitamin D, kidney function and body mass index, who were nonusers of antiresorptives, glucocorticoids and diuretics and not diagnosed with diabetes or thyroid disease). Participants with PTH levels in the upper reference range (5·6-10·2 pmol/l), representing a prevalence of 10·7%, had lower femoral neck and total hip BMD, by 0·030 g/cm(2) [95% confidence interval: 0·009; 0·051] and 0·025 g/cm(2) (0·001; 0·049), respectively, than those with levels 2·7-5·6 pmol/l. Participants with normocalcaemic and secondary hyperparathyroidism also had lower total hip BMD than those with levels 2·7-5·6 pmol/l, and CaMos prevalences of normocalcaemic, primary and secondary hyperparathyroidism were 3·3%, 1·4% and 5·2%, respectively. We found reduced BMD in participants with accepted hyperparathyroid states but also a notable proportion of other participants that might benefit from having lower PTH levels.

Fracture Risk · Risk Factors

Fractures are increased and bisphosphonate use decreased in individuals with insulin-dependent diabetes: a 10 year cohort study

Fraser LA et al., 2014 BMC Musculoskelet Disord Open Access

Individuals with diabetes have been found previously to be at increased risk of non-traumatic fracture. However, it is unclear if these individuals are being identified and treated for osteoporosis. 7753 Canadians over 50 years of age were followed prospectively for 10 years. 606/7753 (7.8%) of had diabetes; 98 were insulin-dependent and 508 were not. Using a cox proportional hazards model, we assessed the association between diabetes status and incident non-traumatic fracture. Using logistic regression we identified factors associated with bisphosphonate use over the 10 year period of study. Mean (SD) age of participants was 66.7(9.4) years and 72% were female. Those with diabetes had higher BMD T-scores at baseline, with a mean (SD) femoral neck T-Score of -0.97 (1.06), compared to -1.24 (0.99) in the general cohort. The adjusted hazard ratio (HR) for incident non-traumatic fracture in individuals with insulin-dependent diabetes over the 10 year study period was 2.50 (95% confidence interval [CI] 1.60, 3.90; p < 0.001). Despite this increased fracture rate, individuals with diabetes (insulin-dependent or non-insulin-dependent) were less likely to be on bisphosphonate therapy at any point over 10 years of prospective follow up compared to other CaMos subjects (odds ratio [OR]: 0.59; 95% CI 0.46-0.75, p < 0.001). Despite the increased risk of non-traumatic fracture associated with insulin-dependent diabetes, we that found individuals with diabetes are less likely to be treated with a bisphosphonate than those without diabetes. These findings point to a possible care gap in the treatment of non-traumatic fractures in individuals with diabetes in Canada.

Fracture Risk · Risk Factors

Effect of Anticholinergic Medications on Falls, Fracture Risk, and Bone Mineral Density Over a 10-Year Period

Fraser LA et al., 2014 Ann Pharmacother Open Access

Many medications used in older adults have strong anticholinergic (ACH) properties, which may increase the risk of falls and fractures. Use of these medications was identified in a population-based Canadian cohort. To identify the fall and fracture risk associated with ACH medication use. Data collection and analysis were conducted at baseline, year 5, and year 10. Cross-sectional analyses were performed to examine associations between ACH medication use and falls. Time-dependent Cox regression was used to examine time to first nontraumatic fracture. Finally, change in bone mineral density (BMD) over 10 years was compared in ACH medication users versus nonusers. Strongly ACH medications were used by 618 of 7753 participants (8.0%) at study baseline, 592 (9.5%) at year 5, and 334 (7.7%) at year 10. Unadjusted ACH medication use was associated with falls at baseline (odds ratio = 1.50; 95% CI = 1.14-1.98; P = 0.004), but the association was no longer significant after covariate adjustment. Similar results occurred at years 5 and 10. ACH medication use was associated with increased incident fracture risk before (hazard ratio = 1.22; CI = 1.13-1.32; P < 0.001) but not after covariate adjustment. Mean (SD) change in femoral neck BMD T-score over 10 years, in those using ACH medications at both years 0 and 5, was -0.60 (0.63) in ACH users versus -0.49 (0.45) in nonusers (P = 0.041), but this was not significant after covariate adjustment. ACH medications were not found to be independently associated with an increased risk of falling, fractures, or BMD loss. Rather, factors associated with ACH medication use explained the apparent associations.

Bone Mineral Density · Measurement

Choice of lumbar spine bone density reference database for fracture prediction in men and women: a population-based analysis

Leslie WD et al., 2014 J Clin Densitom Open Access

The diagnosis of osteoporosis in men is controversial, although most studies demonstrate similar fracture rates for men and women with the same level of hip bone mineral density (BMD). Whether this applies to the lumbar spine is currently uncertain and has important implications with respect to choice of reference population for T-score calculation and osteoporosis diagnosis. This question was specifically addressed in the population-based Canadian Multicentre Osteoporosis Study cohort of 4745 women and 1887 men ages 50+ yr at the time of baseline lumbar spine dual energy x-ray absorptiometry. In up to 10 yr of observation, incident clinical major osteoporotic fractures occurred in 110 men (5.8%) vs 543 women (11.4%) (p < 0.001). Mean lumbar spine BMD in men was greater than in women, both among those with and those without incident major osteoporotic fracture (p < 0.001). Men were at slightly lower risk for incident major osteoporotic fracture than women for an equivalent lumbar spine BMD (ageand BMD-adjusted rate ratio 0.75, 95% confidence interval 0.60-0.93, p = 0.008) with similar findings after adjustment for the World Health Organization fracture risk assessment clinical risk factors or competing mortality. No significant sex difference in the BMD relationship was seen for vertebral fractures (clinical or radiographic) or for all fractures. In summary, this large population-based longitudinal cohort study found similar or lower fracture risk for men vs women after adjustment for absolute lumbar spine BMD and additional covariates. The least complicated model for describing fracture risk is therefore to use the same reference lumbar spine data for generating T-scores in men and women.

Fracture Risk · Risk Factors

Glucocorticoids predict 10-year fragility fracture risk in a population-based ambulatory cohort of men and women: Canadian Multicentre Osteoporosis Study (CaMos)

Ioannidis G et al., 2014 Arch Osteoporos Open Access

We determined the prospective 10-year association among incident fragility fractures and four glucocorticoid (GC) treatment groups (Never GC, Prior GC, Baseline GC, and Ever GC). Results showed that GC treatment is associated with increased 10-year incident fracture risk in ambulatory men and women across Canada. Using the Canadian Multicentre Osteoporosis Study dataset, we determined the prospective 10-year association between incident fragility fractures and GC treatment. We conducted a 10-year prospective observational cohort study at nine sites across Canada. A total of 9,263 ambulatory men and women 25 years of age and older were included in the analysis. Multivariable Cox proportional hazards analyses were conducted to determine the relationship among GC treatment groups in four levels that included Never GC, Prior GC, Baseline GC, and Ever GC (combined baseline and prior groups) and time to fracture. In each of the Never GC, Prior GC, Baseline GC, and Ever GC treatment groups, the number of participants were 8,832 (95.4 %), 303 (3.3 %), 128 (1.4 %), and 431 (4.7 %), respectively. Of the 9,263 individuals enrolled, incident fragility non-spine, hip, spine, and any fractures were experienced by a total of 896 (9.67 %), 157 (1.69 %), 130 (1.40 %), and 1,102 (11.90 %) over 10-years, respectively. For men and women combined, prior GC treatment was associated with a higher hazard ratio (HR) for time to incident non-vertebral (HR = 1.5, 95 % confidence interval [CI] = 1.1, 2.0), hip (HR = 2.1, 95 % CI = 1.1, 4.0), and any fracture (HR = 1.4, 95 % CI = 1.0, 1.8) compared with never GC treatment. GC treatment is associated with increased 10-year incident fracture risk; this highlights the importance of considering therapy to prevent GC-induced fractures for patients who are using GC for various medical conditions.

Fracture Risk · Risk Factors

Antidepressant use and 10-year incident fracture risk: the population-based Canadian Multicentre Osteoporosis Study (CaMoS)

Moura C et al., 2014 Osteoporos Int Open Access

We used data from a large, prospective Canadian cohort to assess the association between selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) and fracture. We found an increased risk of fractures in individuals who used SSRI or SNRI, even after controlling for multiple risk factors. Previous studies have suggested an association between SSRIs and increasing risk of fragility fractures. However, the majority of these studies were not long-term analyses or were performed using administrative data and, thus, could not fully control for potential confounders. We sought to determine whether the use of SSRIs and SNRIs is associated with increased risk of fragility fracture, in adults aged 50 + . We used data from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective randomly selected population-based community cohort; our analyses focused on subjects aged 50+. Time to event methodology was used to assess the association between SSRI/SNRI use, modeled time-dependently, and fragility fracture. Among 6,645 subjects, 192 (2.9%) were using SSRIs or/and SNRIs at baseline. During the 10-year study period, 978 (14.7%) participants experienced at least one fragility fracture. In our main analysis, SSRI/SNRI use was associated with increased risk of fragility fracture (hazard ratio (HR), 1.88; 95% confidence intervals (CI), 1.48-2.39). After controlling for multiple risk factors, including Charlson score, previous falls, and bone mineral density hip and lumbar bone density, the adjusted HR for current SSRI/SNRI use remained elevated (HR, 1.68; 95% CI, 1.32-2.14). Our results lend additional support to an association between SSRI/SNRI use and fragility fractures. Given the high prevalence of antidepressants use, and the impact of fractures on health, our findings may have a significant clinical impact.

Fracture Risk · Risk Factors

A meta-analysis of the association of fracture risk and body mass index in women

Johansson H et al., 2014 J Bone Miner Res

Several recent studies suggest that obesity may be a risk factor for fracture. The aim of this study was to investigate the association between body mass index (BMI) and future fracture risk at different skeletal sites. In prospective cohorts from more than 25 countries, baseline data on BMI were available in 398,610 women with an average age of 63 (range, 20-105) years and follow up of 2.2 million person-years during which 30,280 osteoporotic fractures (6457 hip fractures) occurred. Femoral neck BMD was measured in 108,267 of these women. Obesity (BMI ≥ 30 kg/m(2) ) was present in 22%. A majority of osteoporotic fractures (81%) and hip fractures (87%) arose in non-obese women. Compared to a BMI of 25 kg/m(2) , the hazard ratio (HR) for osteoporotic fracture at a BMI of 35 kg/m(2) was 0.87 (95% confidence interval [CI], 0.85-0.90). When adjusted for bone mineral density (BMD), however, the same comparison showed that the HR for osteoporotic fracture was increased (HR, 1.16; 95% CI, 1.09-1.23). Low BMI is a risk factor for hip and all osteoporotic fracture, but is a protective factor for lower leg fracture, whereas high BMI is a risk factor for upper arm (humerus and elbow) fracture. When adjusted for BMD, low BMI remained a risk factor for hip fracture but was protective for osteoporotic fracture, tibia and fibula fracture, distal forearm fracture, and upper arm fracture. When adjusted for BMD, high BMI remained a risk factor for upper arm fracture but was also a risk factor for all osteoporotic fractures. The association between BMI and fracture risk is complex, differs across skeletal sites, and is modified by the interaction between BMI and BMD. At a population level, high BMI remains a protective factor for most sites of fragility fracture. The contribution of increasing population rates of obesity to apparent decreases in fracture rates should be explored.

Bone Mineral Density · Peak Bone Mass

Longitudinal changes in calcium and vitamin D intakes and relationship to bone mineral density in a prospective population-based study: the Canadian Multicentre Osteoporosis Study (CaMos)

Zhou W et al., 2013 J Musculoskelet Neuronal Interact

Our objective was to study changes in calcium and vitamin D intakes over time, and their cross-sectional and longitudinal associations with bone mineral density (BMD). We followed 9382 women and men aged ≥25 and 899 aged 16-24, for 10 and 2 years respectively. Calcium and vitamin D intakes increased over time in adults, but decreased in women aged 16-18. The increased intakes in adults were largely attributable to the increased use of calcium and/or vitamin D supplements. Both the percentage of supplement users and average dose among users increased over time. There was nevertheless a high prevalence of calcium and vitamin D intake below the estimated average requirement. At baseline, higher calcium and vitamin D intakes were associated with higher total hip and femoral neck BMD in young men, and cumulatively high levels of calcium and vitamin D intakes over time contributed to better BMD maintenance at lumbar spine and hip sites in adult women. Although total intakes, particularly of vitamin D, frequently fell below the Institute of Medicine recommendations despite an increase over time in supplement use, we found some positive associations between total calcium and vitamin D intake and bone health.

Hormones and Bone · Estrogen and Bone

Negative spinal bone mineral density changes and subclinical ovulatory disturbances--prospective data in healthy premenopausal women with regular menstrual cycles

Li D et al., 2013 Epidemiol Rev

Subclinical ovulatory disturbances (anovulation or short luteal phases within normal-length menstrual cycles) indicate lower progesterone-to-estrogen levels. Given that progesterone plays a bone formation role, subclinical ovulatory disturbances may be associated with bone loss or less than expected bone gain. Our purpose was to perform a meta-analysis of prospective studies in healthy premenopausal women to determine the overall relationship of subclinical ovulatory disturbances to change in bone mineral density. Two reviewers independently identified from serial literature searches 6 studies meeting inclusion criteria: a 2-year study in 114 young adult women, 2006-2009, Vancouver, Canada; a 2-year study in 189 premenopausal women, 2000-2005, Toronto, Canada; a single-cycle study in 14 young women, 1996-1997, Melbourne, Australia; an 18-month study in 53 women, 1990-1995, Santa Clara, California; a 4-year study in 27 women, 1988-1995, Vancouver, Canada; and a 1-year study in 66 women, 1985-1988, Vancouver, Canada. This meta-analysis included a combined sample size of 473 observations in 436 premenopausal women studied over 1-4 years and aged 14-47 years. The percentage of women with ovulatory disturbances varied significantly from 13% to 82%. Women with more frequent ovulatory disturbances had more negative percentage changes in spine bone mineral density (weighted mean difference = -0.86; P = 0.040) for random-effects analysis. There was significant heterogeneity among these 6 studies (I(2) = 80%). In summary, these data show that regularly menstruating women with more frequent ovulatory disturbances experience more negative changes in bone (approximately -0.9% per year). These cycles with silent estrogen/progesterone imbalance may be clinically important.

Fracture Risk · Risk Factors

Fracture risk prediction: importance of age, BMD and spine fracture status

Krege JH et al., 2013 Bonekey Rep

Our purpose was to identify factors for a parsimonious fracture risk assessment model considering morphometric spine fracture status, femoral neck bone mineral density (BMD) and the World Health Organization (WHO) clinical risk factors. Using data from 2761 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, longitudinal cohort study of randomly selected community-dwelling men and women aged ⩾50 years, we previously reported that a logistic regression model considering age, BMD and spine fracture status provided as much predictive information as a model considering these factors plus the remaining WHO clinical risk factors. The current analysis assesses morphometric vertebral fracture and/or nonvertebral fragility fracture at 5 years using data from an additional 1964 CaMos subjects who have now completed 5 years of follow-up (total N=4725). Vertebral fractures were identified from lateral spine radiographs assessed using quantititative morphometry at baseline and end point. Nonvertebral fragility fractures were determined by questionnaire and confirmed using radiographs or medical records; fragility fracture was defined as occurring with minimal or no trauma. In this analysis, a model including age, BMD and spine fracture status provided a gradient of risk per s.d. (GR/s.d.) of 1.88 and captured most of the predictive information of a model including morphometric spine fracture status, BMD and all WHO clinical risk factors (GR/s.d. 1.92). For comparison, this model provided more information than a model considering BMD and the WHO clinical risk factors (GR/s.d. 1.74). These findings confirm the value of age, BMD and spine fracture status for predicting fracture risk.

Bone Mineral Density · Peak Bone Mass

Meta-analysis of genome-wide studies identifies WNT16 and ESR1 SNPs associated with bone mineral density in premenopausal women

Koller DL et al., 2012 J Bone Miner Res Open Access

Previous genome-wide association studies (GWAS) have identified common variants in genes associated with variation in bone mineral density (BMD), although most have been carried out in combined samples of older women and men. Meta-analyses of these results have identified numerous single-nucleotide polymorphisms (SNPs) of modest effect at genome-wide significance levels in genes involved in both bone formation and resorption, as well as other pathways. We performed a meta-analysis restricted to premenopausal white women from four cohorts (n = 4061 women, aged 20 to 45 years) to identify genes influencing peak bone mass at the lumbar spine and femoral neck. After imputation, ageand weight-adjusted bone-mineral density (BMD) values were tested for association with each SNP. Association of an SNP in the WNT16 gene (rs3801387; p = 1.7 × 10(-9) ) and multiple SNPs in the ESR1/C6orf97 region (rs4870044; p = 1.3 × 10(-8) ) achieved genome-wide significance levels for lumbar spine BMD. These SNPs, along with others demonstrating suggestive evidence of association, were then tested for association in seven replication cohorts that included premenopausal women of European, Hispanic-American, and African-American descent (combined n = 5597 for femoral neck; n = 4744 for lumbar spine). When the data from the discovery and replication cohorts were analyzed jointly, the evidence was more significant (WNT16 joint p = 1.3 × 10(-11) ; ESR1/C6orf97 joint p = 1.4 × 10(-10) ). Multiple independent association signals were observed with spine BMD at the ESR1 region after conditioning on the primary signal. Analyses of femoral neck BMD also supported association with SNPs in WNT16 and ESR1/C6orf97 (p < 1 × 10(-5) ). Our results confirm that several of the genes contributing to BMD variation across a broad age range in both sexes have effects of similar magnitude on BMD of the spine in premenopausal women. These data support the hypothesis that variants in these genes of known skeletal function also affect BMD during the premenopausal period.

Bone Mineral Density · Measurement

The relationship between proton pump inhibitor use and longitudinal change in bone mineral density: a population-based study [corrected] from the Canadian Multicentre Osteoporosis Study (CaMos)

Targownik LE et al., 2012 Am J Gastroenterol

Proton pump inhibitor (PPI) use has been identified as a risk factor for hip and vertebral fractures. Evidence supporting a relationship between PPI use and osteoporosis remains scant. Demonstrating that PPIs are associated with accelerated bone mineral density (BMD) loss would provide supportive evidence for a mechanism through which PPIs could increase fracture risk. We used the Canadian Multicentre Osteoporosis Study data set, which enrolled a population-based sample of Canadians who underwent BMD testing of the femoral neck, total hip, and lumbar spine (L1-L4) at baseline, and then again at 5 and 10 years. Participants also reported drug use and exposure to risk factors for osteoporosis and fracture. Multivariate linear regression was used to determine the independent association of PPI exposure and baseline BMD, and on change in BMD at 5 and 10 years. In all, 8,340 subjects were included in the baseline analysis, with 4,512 (55%) undergoing year 10 BMD testing. After adjusting for potential confounders, PPI use was associated with significantly lower baseline BMD at the femoral neck and total hip. PPI use was not associated with a significant acceleration in covariate-adjusted BMD loss at any measurement site after 5 and 10 years of follow-up. PPI users had lower BMD at baseline than PPI non-users, but PPI use over 10 years did not appear to be associated with accelerated BMD loss. The reasons for discordant findings between PPI use at baseline and during follow-up require further study.

Hormones and Bone · Estrogen and Bone

Temporal trends and determinants of longitudinal change in 25-hydroxyvitamin D and parathyroid hormone levels

Berger C et al., 2012 J Bone Miner Res Open Access

Vitamin D is essential for facilitating calcium absorption and preventing increases in parathyroid hormone (PTH), which can augment bone resorption. Our objectives were to examine serum levels of 25-hydroxyvitamin D [25(OH)D] and PTH, and factors related to longitudinal change in a population-based cohort. This is the first longitudinal population-based study looking at PTH and 25(OH)D levels. We analyzed 3896 blood samples from 1896 women and 829 men in the Canadian Multicentre Osteoporosis Study over a 10-year period starting in 1995 to 1997. We fit hierarchical models with all available data and adjusted for season. Over 10 years, vitamin D supplement intake increased by 317 (95% confidence interval [CI] 277 to 359) IU/day in women and by 193 (135 to 252) IU/day in men. Serum 25(OH)D (without adjustment) increased by 9.3 (7.3 to 11.4) nmol/L in women and by 3.5 (0.6 to 6.4) nmol/L in men but increased by 4.7 (2.4 to 7.0) nmol/L in women and by 2.7 (-0.6 to 6.2) nmol/L in men after adjustment for vitamin D supplements. The percentage of participants with 25(OH)D levels <50 nmol/L was 29.7% (26.2 to 33.2) at baseline and 19.8% (18.0 to 21.6) at year 10 follow-up. PTH decreased over 10 years by 7.9 (5.4 to 11.3) pg/mL in women and by 4.6 (0.2 to 9.0) pg/mL in men. Higher 25(OH)D levels were associated with summer, younger age, lower body mass index (BMI), regular physical activity, sun exposure, and higher total calcium intake. Lower PTH levels were associated with younger age and higher 25(OH)D levels in both women and men and with lower BMI and participation in regular physical activity in women only. We have observed concurrent increasing 25(OH)D levels and decreasing PTH levels over 10 years. Secular increases in supplemental vitamin D intake influenced both changes in serum 25(OH)D and PTH levels.

Hormones and Bone · Contraceptive Effects on Bone

Low-dose estrogen combined oral contraceptives may negatively influence physiological bone mineral density acquisition during adolescence

Cibula D et al., 2012 European journal of endocrinology

The aim was to evaluate changes of bone mineral density (BMD) and markers of bone turnover in healthy adolescents, and in adolescent users of combined oral contraceptives (COCs) with different ethinylestradiol (EE) contents. In this prospective crossover study, 56 healthy females (15-19.5 years) with desire to use hormonal contraception were randomized to COC with either 30 or 15 μg of EE in crossover design of 9-month intervention each in reverse order. Nonusers of the same age (n=28) served as controls. BMD at lumbar spine (LS), total femur, femoral neck, distal radius, and total body, and serum markers (N-propeptide of type I procollagen, and type I collagen C-telopeptide) were measured at baseline and after 9 and 18 months. In COC nonusers, BMD significantly increased at LS and radius, while markers decreased. In COC users, BMD did not increase, with the exception of LS BMD in the 30 μg COC group (P<0.05). In the crossover design, a difference between the low- and very low-dose COC users was found in LS BMD changes (P<0.05), where increase in BMD was more impaired in the 15 μg COC users. The skeletal effects of COC remained significant after adjustments for age and smoking status. Markers declined faster in COC users during the first period, while they remained stable or even increased during the second 9 months. Physiological acquisition of LS BMD during adolescent age may be prevented by use of COC, especially those containing very low dose of EE.

Osteoporosis · Diagnosis and Treatment

Should risk of bone fragility restrict weight control for other health reasons in postmenopausal women?--A ten year prospective study

Sirola J et al., 2012 Maturitas

The aim of the present study was to investigate the health risks of excess body weight in the light of its protective effects on bone fragility. Femoral neck and lumbar spine dual X-ray absorptiometry was performed for 1970 Finnish women with a mean baseline age of 58.8 years (range 53.1-65.7 years) in 1994 and 2004. Women were categorized according to baseline BMI into normal <25 kg/m2, overweight 25-29.9 kg/m(2) and obese ≥30 kg/m(2). Weight change (kg) was categorized into tertiles. Co-morbidities, not allowed to be present at baseline, was based on self-reports. Osteoporosis was defined as femoral neck or spinal (L2-L4) T-score <-2.5 SD at 10-year follow-up or <-2.0 SD+low trauma energy follow-up fracture. Uniand multivariate logistic regression models were used to estimate the 10-year risk of incident health disorders. Adjustment for age, number of diseases, alcohol intake and smoking was used in the multivariate models. Obesity (Ob) and overweight (Ow) were related with higher 10-year risk of hypertension (OR=2.6 (Ob)/OR=1.7 (Ow), p<0.001), coronary artery disease (OR=1.6, p<0.05/OR=1.2, p=NS), diabetes (OR=11.7/OR=5.3, p<0.001), osteoarthritis (OR=1.4, p<0.05/OR=1.1, p=NS), chronic back pain (OR=1.6, p=0.007/OR=1.2, p=NS) and poor self-rated health (OR=2.4, p<0.05/OR=1.5, p=NS) and lower risk of osteoporosis (OR=0.13/OR=0.28, p<0.001). Weight change of less than +1 kg was associated 1.8 and 2.6 times lower 10-year risk of having hypertension and breast cancer than weight change over 6.2 kg. Among obese women the absolute risk increase of hypertension was 17%, of diabetes 12%, and absolute risk reduction of osteoporosis 14% in comparison to BMI <25 kg/m(2). Health related risks of high BMI outweigh its protective effects on bone. Weight gain increases the risk hypertension and breast cancer.

Bone Mineral Density · Measurement

Physical activity, body mass index and bone mineral density-associations in a prospective population-based cohort of women and men: the Canadian Multicentre Osteoporosis Study (CaMos)

Langsetmo L et al., 2012 Bone Open Access

Physical activity (PA) is an important modifiable risk factor for both bone mineral density (BMD) and body mass index (BMI). However, BMI is itself strongly predictive of BMD. Our aim was to determine the association between PA and BMD, with consideration of BMI as a potential mediating factor. The Canadian Multicentre Osteoporosis Study (CaMos) is a population-based prospective cohort study of Canadian women and men. PA was determined from interviewer-administered questionnaires at baseline and Year 5 and summarized as daily energy expenditure in total metabolic equivalents of the task multiplied by minutes/day (MET*m/d). Height, weight, and total hip and lumbar spine BMD were measured at baseline and Year 5. General linear models assessed relationships between PA and BMD, both cross-sectionally (baseline PA with baseline BMD) and longitudinally (average PA and change in PA with change in BMD). BMI was considered as a mediating factor. Potential confounders included age, center, education, caffeine intake, alcohol exposure, smoking history, history of weight-cycling, age at menarche, past use of oral contraceptives, history of >3 months missed menstruation, menopausal status, and antiresorptive use, as relevant. The study included 2855 men and 6442 women. PA was inversely associated with BMI at baseline, and an increase in PA between baseline and Year 5 was associated with a decrease in BMI, with 0.41 (95% CI: 0.22, 0.60) kg/m(2) loss per 1000 MET*m/d increase (in men) and 0.40 (95% CI: 0.23, 0.57) kg/m(2) loss per 1000 MET*m/d increase (in women). BMI was strongly associated with BMD, both cross-sectionally and longitudinally. However, increased PA was associated with a small increase in total hip BMD, 0.004 (95% CI: 0.000-0.008) g/cm(2) per 1000 MET*m/d (in men) and 0.003 (95% CI: 0.000-0.007) g/cm(2) per 1000 MET*m/d (in women). Average PA was associated with an increase in lumbar spine BMD in women, but not in men; it was not associated with change in total hip BMD in either sex. Increased PA is associated with an increase in BMD and a concomitant decrease in BMI. These findings suggest that population-level interventions to increase PA would favorably impact bone and other health outcomes.

Fracture Risk · Risk Factors

Predicting fracture using 2D finite element modelling

MacNeil JA et al., 2012 Med Eng Phys Open Access

A decrease in bone density at the hip or spine has been shown to increase the risk of fracture. A limitation of the bone mineral density (BMD) measurement is that it provides only a measure of a bone sample's average density when projected onto a 2D surface. Effectively, what determines bone fracture is whether an applied load exceeds ultimate strength, with both bone tissue material properties (can be approximated through bone density), and geometry playing a role. The goal of this project was to use bone geometry and BMD obtained from radiographs and DXA measurements respectively to estimate fracture risk, using a two-dimensional finite element model (FEM) of the sagittal plane of lumbar vertebrae. The Canadian Multicentre Osteoporosis Study (CaMos) data was used for this study. There were 4194 men and women over the age of 50 years, with 786 having fractures. Each subject had BMD testing and radiographs of their lumbar vertebrae. A single two dimensional FEM of the first to fourth lumbar vertebra was automatically generated for each subject. Bone tissue stiffness was assigned based on the BMD of the individual vertebrae, and adjusted for patient age. Axial compression boundary conditions were applied with a force proportional to body mass. The resulting overall strain from the applied force was found. Men and women were analyzed separately. At baseline, the sensitivity of BMD to predict fragility fractures in women and men was 3.77% and 0.86%, while the sensitivity of FEM to predict fragility fractures for women and men was 10.8% and 11.3%. The FEM ROC curve demonstrated better performance compared to BMD. The relative risk of being considered at high fracture risk using FEM at baseline, was a better predictor of 5 year incident fragility fracture risk compared to BMD.

Fracture Risk · Risk Factors

Spine-hip T-score difference predicts major osteoporotic fracture risk independent of FRAX(®): a population-based report from CAMOS

Leslie WD et al., 2011 J Clin Densitom Open Access

The WHO fracture risk assessment tool (FRAX(®)) estimates an individual's 10-yr major osteoporotic and hip fracture probabilities. When bone mineral density (BMD) is included in the FRAX calculation, only the femoral neck measurement can be used. Recently, a procedure was reported for adjusting major osteoporotic fracture probability from FRAX with femoral neck BMD based on the difference (offset) between the lumbar spine and the femoral neck T-score values. The objective of the current analysis was to independently evaluate this algorithm in a population-based cohort of 4575 women and 1813 men aged 50 yr and older from the Canadian Multicentre Osteoporosis Study. For women and men combined, there was a 15% (95% confidence interval 7-24%) increase in major osteoporotic fracture risk for each offset T-score after adjusting for FRAX probability calculated with femoral neck BMD. The effect was stronger in women than men, but a significant sex interaction was not detected. Among the full cohort, 5.5% had their risk category reclassified after using the offset adjustment. Sexand age-dependent offsets (equivalent to an offset based on Z-scores) showed improved risk classification among individuals designated to be at moderate risk with the conventional FRAX probability measurement. In summary, the T-score difference between the lumbar spine and femoral neck is an independent risk factor for major osteoporotic fractures that is independent of the FRAX probability calculated with femoral neck BMD.

Hormones and Bone · Contraceptive Effects on Bone

The association between oral contraceptive use, bone mineral density and fractures in women aged 50-80 years

Wei S et al., 2011 Contraception Open Access

The associations between oral contraceptive (OC) use, bone mineral density (BMD) and the risk of fractures remain controversial. A cross-sectional study of 491 women aged 50-80 years was performed. We assessed OC use and fractures by questionnaire, and BMD and vertebral deformity by dual-energy x-ray absorptiometry. Ever use of OC was associated with significantly higher BMD at the total body (6%, p<.001) and spine (4%; p=.05) (but not hip) after adjustment for confounders. There was also a significant association between duration of OC use and total body and spine BMD. Use of OCs for 5-10 years was associated with reduced vertebral deformity (adjusted odds ratio 0.46, 95% confidence interval 0.22-0.94). Oral contraceptive use and duration were associated with higher total body and spine BMD and a consistent reduction in vertebral deformities, although most associations did not reach significance.

Fracture Risk · Risk Factors

Is the oral contraceptive pill associated with fracture in later life? New evidence from the Royal College of General Practitioners Oral Contraception Study

Memon S et al., 2011 Contraception

Several studies, including an earlier analysis from the Royal College of General Practitioners (RCGP) Oral Contraception Study, have suggested that ever users of oral contraceptives have an increased risk of fracture when compared with never users. In this paper, we examined a subset of women in the RCGP study living in Scotland to determine whether this risk has persisted. A nested case-control study was carried out using data collected prospectively for the RCGP Oral Contraception Study. Cases were women with a first ever diagnosis of fracture (n=651), age-matched to two controls (n=1302). Adjustments were made for smoking, social class and parity. There was not a significant association between ever use of oral contraception and fracture (adjusted odds ratio 1.05, 95% confidence interval 0.86-1.29), compared with never users. Neither were significant associations found between fracture and smoking, social class and parity. The findings did not vary materially with age or type of fracture. Ever use of oral contraception was not associated with fracture in this study.

Fracture Risk · Risk Factors

Independent external validation of nomograms for predicting risk of low-trauma fracture and hip fracture

Langsetmo L et al., 2011 CMAJ Open Access

A set of nomograms based on the Dubbo Osteoporosis Epidemiology Study predicts the fiveand ten-year absolute risk of fracture using age, bone mineral density and history of falls and low-trauma fracture. We assessed the discrimination and calibration of these nomograms among participants in the Canadian Multicentre Osteoporosis Study. We included participants aged 55-95 years for whom bone mineral density measurement data and at least one year of follow-up data were available. Self-reported incident fractures were identified by yearly postal questionnaire or interview (years 3, 5 and 10). We included low-trauma fractures before year 10, except those of the skull, face, hands, ankles and feet. We used a Cox proportional hazards model. Among 4152 women, there were 583 fractures, with a mean follow-up time of 8.6 years. Among 1606 men, there were 116 fractures, with a mean follow-up time of 8.3 years. Increasing age, lower bone mineral density, prior fracture and prior falls were associated with increased risk of fracture. For low-trauma fractures, the concordance between predicted risk and fracture events (Harrell C) was 0.69 among women and 0.70 among men. For hip fractures, the concordance was 0.80 among women and 0.85 among men. The observed fracture risk was similar to the predicted risk in all quintiles of risk except the highest quintile of women, where it was lower. The net reclassification index (19.2%, 95% confidence interval [CI] 6.3% to 32.2%), favours the Dubbo nomogram over the current Canadian guidelines for men. Interpretation: The published nomograms provide good fracture-risk discrimination in a representative sample of the Canadian population.

Fracture Risk · Risk Factors

Fracture prediction and calibration of a Canadian FRAX® tool: a population-based report from CaMos

Fraser LA et al., 2011 Osteoporos Int Open Access

A new Canadian WHO fracture risk assessment (FRAX®) tool to predict 10-year fracture probability was compared with observed 10-year fracture outcomes in a large Canadian population-based study (CaMos). The Canadian FRAX tool showed good calibration and discrimination for both hip and major osteoporotic fractures. The purpose of this study was to validate a new Canadian WHO fracture risk assessment (FRAX®) tool in a prospective, population-based cohort, the Canadian Multicentre Osteoporosis Study (CaMos). A FRAX tool calibrated to the Canadian population was developed by the WHO Collaborating Centre for Metabolic Bone Diseases using national hip fracture and mortality data. Ten-year FRAX probabilities with and without bone mineral density (BMD) were derived for CaMos women (N = 4,778) and men (N = 1,919) and compared with observed fracture outcomes to 10 years (Kaplan-Meier method). Cox proportional hazard models were used to investigate the contribution of individual FRAX variables. Mean overall 10-year FRAX probability with BMD for major osteoporotic fractures was not significantly different from the observed value in men [predicted 5.4% vs. observed 6.4% (95%CI 5.2-7.5%)] and only slightly lower in women [predicted 10.8% vs. observed 12.0% (95%CI 11.0-12.9%)]. FRAX was well calibrated for hip fracture assessment in women [predicted 2.7% vs. observed 2.7% (95%CI 2.2-3.2%)] but underestimated risk in men [predicted 1.3% vs. observed 2.4% (95%CI 1.7-3.1%)]. FRAX with BMD showed better fracture discrimination than FRAX without BMD or BMD alone. Age, body mass index, prior fragility fracture and femoral neck BMD were significant independent predictors of major osteoporotic fractures; sex, age, prior fragility fracture and femoral neck BMD were significant independent predictors of hip fractures. The Canadian FRAX tool provides predictions consistent with observed fracture rates in Canadian women and men, thereby providing a valuable tool for Canadian clinicians assessing patients at risk of fracture.

Fracture Risk · Risk Factors

Construction and validation of a simplified fracture risk assessment tool for Canadian women and men: results from the CaMos and Manitoba cohorts

Leslie WD et al., 2011 Osteoporos Int Open Access

A procedure for creating a simplified version of fracture risk assessment tool (FRAX®) is described. Calibration, fracture prediction, and concordance were compared with the full FRAX tool using two large, complementary Canadian datasets. The Canadian Association of Radiologists and Osteoporosis Canada (CAROC) system for fracture risk assessment is based upon sex, age, bone mineral density (BMD), prior fragility fracture, and glucocorticoid use. CAROC does not require computer or web access, and categorizes 10-year major osteoporotic fracture risk as low (<10%), moderate (10-20%), or high (>20%). Basal CAROC fracture risk tables (by age, sex, and femoral neck BMD) were constructed from Canadian FRAX probabilities for major osteoporotic fractures (adjusted for prevalent clinical risk factors). We assessed categorization and fracture prediction with the updated CAROC system in the CaMos and Manitoba BMD cohorts. The new CAROC system demonstrated high concordance with the Canadian FRAX tool for risk category in both the CaMos and Manitoba cohorts (89% and 88%). Ten-year fracture outcomes in CaMos and Manitoba BMD cohorts showed good discrimination and calibration for both CAROC (6.1-6.5% in low-risk, 13.5-14.6% in moderate-risk, and 22.3-29.1% in high-risk individuals) and FRAX (6.1-6.6% in low-risk, 14.4-16.1% in moderate-risk, and 23.4-31.0% in high-risk individuals). Reclassification from the CAROC risk category to a different risk category under FRAX occurred in <5% for low-risk, 20-24% for moderate-risk, and 27-30% for high-risk individuals. Reclassified individuals had 10-year fracture outcomes that were still within or close to the original nominal-risk range.. The new CAROC system is well calibrated to the Canadian population and shows a high degree of concordance with the Canadian FRAX tool. The CAROC system provides s a simple alternative when it is not feasible to use the full Canadian FRAX tool.

Osteoporosis · Diagnosis and Treatment

Fragility fractures and the osteoporosis care gap in women: the Canadian Multicentre Osteoporosis Study

Fraser LA et al., 2011 Osteoporos Int Open Access

Canadian women over 50 years old were studied over a 10-year period to see if those who sustained a fracture (caused by minimal trauma) were receiving the recommended osteoporosis therapy. We found that approximately half of these women were not being treated, indicating a significant care gap in osteoporosis treatment. Prevalent fragility fracture strongly predicts future fracture. Previous studies have indicated that women with fragility fractures are not receiving the indicated treatment. We aimed to describe post fracture care in Canadian women using a large, population-based prospective cohort that began in 1995-1997. We followed 5,566 women over 50 years of age from across Canada over a period of 10 years in the Canadian Multicentre Osteoporosis Study. Information on medication use and incident clinical fragility fractures was obtained during a yearly questionnaire or interview and fractures were confirmed by radiographic/medical reports. Over the 10-year study period, 42-56% of women with yearly incident clinical fragility fractures were not treated with an osteoporosis medication. During year 1 of the study, 22% of the women who had experienced a fragility fracture were on treatment with a bisphosphonate and 26% were on hormone therapy (HT). We were not able to differentiate HT use for menopause symptoms vs osteoporosis. Use of bisphosphonate therapy increased over time; odds ratio (OR) for use at year 10 compared to use at year 1 was 3.65 (95% confidence interval (CI) 1.83-7.26). In contrast, HT use declined, with an OR of 0.07 (95%CI 0.02-0.24) at year 10 compared to year 1 of the study. In a large population-based cohort study, we found a therapeutic care gap in women with osteoporosis and fragility fractures. Although bisphosphonate therapy usage improved over time, a substantial gap remains.

Hormones and Bone · Estrogen and Bone

Bone changes and fracture related to menstrual cycles and ovulation

Kalyan S et al., 2010 Crit Rev Eukaryot Gene Expr

Women's menstrual cycles and bone remodeling are linked in part by their co-dependency on the stressand resource-associated variables that govern both of their cyclical natures. Therefore, it is not surprising that evolution has resulted in the same signaling molecules and pathways that regulate normal ovarian function to be involved in bone remodeling and turnover. This review will first provide an overview of the normal menstrual cycle, its modification by age and ovulatory disturbances, and how it parallels bone remodeling. Epidemiological and clinical evidence will be presented that link bone remodeling, strength, and fractures with women's history of reproductive and menstrual cycle characteristics. This combined evidence will then be presented alongside a synthesis of current concepts derived from basic science investigations focused on understanding the molecular mechanisms underlying the influence of ovarian factors on bone physiology. Osteoporosis is a significant source of morbidity for older women. The data presented in this review suggest that a woman's reproductive cycle and ovulatory characteristics foreshadow the future health of her bones. More importantly, identifying the key mechanisms underlying reproductive and bone health would not only provide essential preventative strategies, but may also uncover attractive targets for the treatment of osteoporosis.

Fracture Risk · Risk Factors

Dietary patterns and incident low-trauma fractures in postmenopausal women and men aged ≥ 50 y: a population-based cohort study

Langsetmo L et al., 2010 Am J Clin Nutr Open Access

Previous research has shown that dietary patterns are related to the risk of several adverse health outcomes, but the relation of these patterns to skeletal fragility is not well understood. Our objective was to determine the relation between dietary patterns and incident fracture and possible mediation of this relation by body mass index, bone mineral density, or falls. We performed a retrospective cohort study based on the Canadian Multicentre Osteoporosis Study-a randomly selected population-based cohort. We assessed dietary patterns by using self-administered food-frequency questionnaires in year 2 of the study (1997-1999). Our primary outcome was low-trauma fracture occurring before the 10th annual follow-up (2005-2007). We identified 2 dietary patterns by using factor analysis. The first factor (nutrient dense) was strongly associated with intake of fruit, vegetables, and whole grains. The second factor (energy dense) was strongly associated with intake of soft drinks, potato chips, French fries, meats, and desserts. The nutrient-dense factor was associated with a reduced risk of fracture per 1 SD in men overall [hazard ratio (HR): 0.83; 95% CI: 0.64, 1.08] and in women overall (HR: 0.86; 95% CI: 0.76, 0.98). An age trend (P = 0.03) was observed, which yielded an HR of 0.97 in younger women (age < 70 y) compared with an HR of 0.82 in older women (age ≥ 70 y). The associations were independent of body mass index, bone mineral density, falls, and demographic variables. The energy-dense pattern was not related to fracture. A diet high in vegetables, fruit, and whole grains may reduce the risk of low-trauma fracture, particularly in older women.

Hormones and Bone · Estrogen and Bone

Progesterone and bone: actions promoting bone health in women

Seifert-Klauss V et al., 2010 J Osteoporos Open Access

Estradiol (E(2)) and progesterone (P(4)) collaborate within bone remodelling on resorption (E(2)) and formation (P(4)). We integrate evidence that P(4) may prevent and, with antiresorptives, treat women's osteoporosis. P(4) stimulates osteoblast differentiation in vitro. Menarche (E(2)) and onset of ovulation (P(4)) both contribute to peak BMD. Meta-analysis of 5 studies confirms that regularly cycling premenopausal women lose bone mineral density (BMD) related to subclinical ovulatory disturbances (SODs). Cyclic progestin prevents bone loss in healthy premenopausal women with amenorrhea or SOD. BMD loss is more rapid in perimenopause than postmenopause-decreased bone formation due to P(4) deficiency contributes. In 4 placebo-controlled RCTs, BMD loss is not prevented by P(4) in postmenopausal women with increased bone turnover. However, 5 studies of E(2)-MPA co-therapy show greater BMD increases versus E(2) alone. P(4) fracture data are lacking. P(4) prevents bone loss in preand possibly perimenopausal women; progesterone co-therapy with antiresorptives may increase bone formation and BMD.

Bone Mineral Density · Measurement

Using the same bone density reference database for men and women provides a simpler estimation of fracture risk

Langsetmo L et al., 2010 J Bone Miner Res Open Access

Although low bone mineral density (BMD) predicts fractures, there are postulated sex differences in the fracture "threshold." Some studies demonstrate a higher mean BMD for men with fractures than for women, whereas others note similar absolute risk at the same level of BMD. Our objective was to test the preceding observations in the population-based Canadian Multicentre Osteoporosis Study (CaMOS). We included participants 50+ years of age at baseline. Mean BMD in men was higher than in women among both fracture cases and noncases. Three methods of BMD normalization were compared in age-adjusted Cox proportional hazards models. In a model using the same reference population mean and standard deviation (SD), there were strong effects of age and total-hip BMD for prediction of fractures but no significant effect of sex [hazard ratio (HR) = 0.97, 95% confidence interval (CI) 0.78-1.20] for men versus women. In a model using sex-specific reference means but a common SD, an apparent sex difference emerged (HR = 0.66, 95% CI 0.54-0.81) for men versus women. The sex term in the second model counterbalanced the higher risk introduced by the lower normalized BMD in men. A third model using sex-specific reference means and SDs gave nearly identical results. Parallel results for the three methods of normalization were seen when adjusting for clinical risk factors, excluding antiresorptive users and considering death as a competing risk. We conclude that no adjustment for sex is necessary when using common reference data for both men and women, whereas using sex-specific reference data requires a substantial secondary adjustment for sex.

Fracture Risk · Risk Factors

Determining whether women with osteopenic bone mineral density have low, moderate, or high clinical fracture risk

Langsetmo L et al., 2010 Menopause Open Access

Most low-trauma fractures occur among women with osteopenic bone mineral density (BMD), a population considered to have moderate absolute fracture risk. Our purpose was to refine the fracture risk prediction in women with osteopenic BMD to determine the subgroups at lowest and highest risk. We included 2,588 women aged 50 to 90 years with osteopenic BMD (femoral neck BMD between -1 and -2.5) participating in the Canadian Multicentre Osteoporosis Study, an ongoing prospective cohort study of randomly selected Canadians. Baseline variables, in addition to known risk factors, age, and BMD, were considered for inclusion in a model for the prediction of 5-year absolute risk of low-trauma fracture. Models were derived using logistic regression and assessed by the Bayesian Information Criterion. We found an increased fracture risk among those with lower BMD (odds ratio [OR], 1.53; 95% CI, 1.06-2.21) for each decrease in femoral neck T score (eg, from -1 to -2), those with prior low-trauma fracture (OR, 2.06; 95% CI, 1.46-2.92), those with self-reported worse general health (OR, 1.35; 95% CI, 1.15-1.59) for each lower category (categories: excellent, very good, good, fair, poor), and those with height loss (OR, 1.44; 95% CI, 1.16-1.90) for each 5-cm difference between current and maximal height. The new model had yielded a better risk stratification than did a model with World Health Organization risk factors. Including risk factors such as general health and height loss can be used to provide a highly effective assessment of fracture risk among women with osteopenic BMD.

Osteoporosis · Diagnosis and Treatment

Peak bone mass from longitudinal data: implications for the prevalence, pathophysiology, and diagnosis of osteoporosis

Berger C et al., 2010 J Bone Miner Res Open Access

We estimated peak bone mass (PBM) in 615 women and 527 men aged 16 to 40 years using longitudinal data from the Canadian Multicentre Osteoporosis Study (CaMos). Individual rates of change were averaged to find the mean rate of change for each baseline age. The age range for PBM was defined as the period during which bone mineral density (BMD) was stable. PBM was estimated via hierarchical models, weighted according to 2006 Canadian Census data. Lumbar spine PBM (1.046 ± 0.123 g/cm(2)) occurred at ages 33 to 40 years in women and at 19 to 33 years in men (1.066 ± 0.129 g/cm(2)). Total hip PBM (0.981 ± 0.122 g/cm(2)) occurred at ages 16 to 19 years in women and 19 to 21 years in men (1.093 ± 0.169 g/cm(2)). Analysis of Canadian geographic variation revealed that the levels of PBM and of mean BMD in those over age 65 sometimes were discordant, suggesting that PBM and subsequent rates of bone loss may be subject to different genetic and/or environmental influences. Based on our longitudinally estimated PBM values, the estimated Canadian prevalences of osteoporosis (T-score < -2.5) were 12.0% (L(1)-L(4)) and 9.1% (total hip) in women aged 50 years and older and 2.9% (L(1)-L(4)) and 0.9% (total hip) in men aged 50 years and older. These were higher than prevalences using cross-sectional PBM data. In summary, we found that the age at which PBM is achieved varies by sex and skeletal site, and different reference values for PBM lead to different estimates of the prevalence of osteoporosis. Furthermore, lack of concordance of PBM and BMD over age 65 suggests different determinants of PBM and subsequent bone loss.

Bone Mineral Density · Peak Bone Mass

Normative bone mineral density z-scores for Canadians aged 16 to 24 years: the Canadian Multicenter Osteoporosis Study

Zhou W et al., 2010 J Clin Densitom Open Access

The objectives of the study were to develop bone mineral density (BMD) reference norms and BMD Z-scores at various skeletal sites, to determine whether prior fracture and/or asthma were related to BMD, and to assess possible geographic variation of BMD among Canadian youth aged 16-24 yr. Z-Scores were defined as the number of standard deviations from the mean BMD of a healthy population of the same age, race, and sex. Z-Scores were calculated using the reference sample defined as Canadian Caucasian participants without asthma or prior fracture. Reference standards were created for lumbar spine (L1-L4), femoral neck, total hip, and greater trochanter, by each year of age (16-24 yr), and by sex. The Z-score norms were developed for groups noted earlier. Mean Z-scores between the asthma or fracture subgroups compared with the mean Z-scores in the reference sample were not different. There were minor differences in mean BMD across different Canadian geographic regions. This study provides age, sex, and skeletal site-specific Caucasian reference norms and formulae for the calculation of BMD Z-scores for Canadian youth aged 16-24 yr. This information will be valuable to help to identify individuals with clinically meaningful low BMD.

Fracture Risk · Risk Factors

Repeat low-trauma fractures occur frequently among men and women who have osteopenic BMD

Langsetmo L et al., 2009 J Bone Miner Res Open Access

Fracture risk assessment based solely on BMD has limitations. Additional risk factors include the presence of a previous low-trauma fracture. We sought to quantify the fracture burden attributable to first versus repeat fracture. We studied 2179 men and 5269 women, 50-90 yr of age, participating in the Canadian Multicentre Osteoporosis Study (CaMos). We included all low-trauma fractures that occurred over 8 yr of follow-up and classified these as either first or repeat clinical low-trauma fracture based on lifetime fracture history. Analyses were further stratified by sex, age, BMD risk categories (normal, osteopenia, osteoporosis), and vertebral deformity status. There were 128 fractures in men and 577 fractures in women. About 25% of fractures in men and 40% in women were repeat fractures. Just over one half of first fractures occurred in those with osteopenic BMD (58% in men, 54% in women). Just under one half of repeat fractures also occurred in those with osteopenic BMD (42% in men, 47% in women). The incidence of repeat fracture was, in most cases, nearly double, but sometimes nearly quadruple, the incidence of first fracture within a given BMD risk category in both men and women. Repeat fractures contribute substantially to overall fracture burden, and the contribution is independent of BMD. Furthermore, those with a combination of prior low-trauma fracture and another risk factor were at especially high risk of future fracture.

Osteoporosis · Diagnosis and Treatment

Relation between fractures and mortality: results from the Canadian Multicentre Osteoporosis Study

Ioannidis G et al., 2009 CMAJ Open Access

Fractures have largely been assessed by their impact on quality of life or health care costs. We conducted this study to evaluate the relation between fractures and mortality. A total of 7753 randomly selected people (2187 men and 5566 women) aged 50 years and older from across Canada participated in a 5-year observational cohort study. Incident fractures were identified on the basis of validated self-report and were classified by type (vertebral, pelvic, forearm or wrist, rib, hip and "other"). We subdivided fracture groups by the year in which the fracture occurred during follow-up; those occurring in the fourth and fifth years were grouped together. We examined the relation between the time of the incident fracture and death. Compared with participants who had no fracture during follow-up, those who had a vertebral fracture in the second year were at increased risk of death (adjusted hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.1-6.6); also at risk were those who had a hip fracture during the first year (adjusted HR 3.2, 95% CI 1.4-7.4). Among women, the risk of death was increased for those with a vertebral fracture during the first year (adjusted HR 3.7, 95% CI 1.1-12.8) or the second year of follow-up (adjusted HR 3.2, 95% CI 1.2-8.1). The risk of death was also increased among women with hip fracture during the first year of follow-up (adjusted HR 3.0, 95% CI 1.0-8.7). Interpretation: Vertebral and hip fractures are associated with an increased risk of death. Interventions that reduce the incidence of these fractures need to be implemented to improve survival.

Bone Mineral Density · Measurement

Direct-to-participant feedback and awareness of bone mineral density testing results in a population-based sample of mid-aged Canadians

Kingwell E et al., 2009 Osteoporos Int

This population-based study of mid-aged Canadians assessed awareness of diagnosis by bone mineral density (BMD) following dual-energy X-ray absorptiometry (DXA) testing and compared the effects of feedback only to the physician with direct-to-participant feedback. Poor recall of osteoporosis results was observed irrespective of the feedback destination, but direct-to-participant feedback improved recall of borderline or normal results. BMD testing provides information about fracture risk. This study assessed whether awareness of results, in a random population sample of mid-aged Canadians, differed if results were provided to physicians only or directly to participants. Prospective cohort study of 2,678 women and men aged 40-60 years from the Canadian Multicentre Osteoporosis Study. Participants completed hip and spine DXA and interviewer-administered questionnaires regarding demographics and osteoporosis risk factors. Lateral spine X-rays were conducted on those > or =50 years of age. All test results were reported to the participant, the family physician or both. Associations between BMD results, feedback destination and correct self-report results, 3 years later, were assessed using logistic regression while adjusting for potential confounders. Only 25% of men and 33% of women correctly reported their osteoporosis diagnoses. Direct-to-participant vs. physician-only reports did not improve recall of osteoporosis diagnosis but improved recall of borderline or normal BMD. Older (vs. younger) men and men with prevalent vertebral fractures demonstrated better recall of their osteoporosis diagnosis. Recall of low BMD results was poor, despite direct-to-participant feedback and even in the presence of other osteoporosis risk factors. Direct-to-participant feedback may improve awareness of borderline or normal BMD results.

Fracture Risk · Risk Factors

Vertebral fracture status and the World Health Organization risk factors for predicting osteoporotic fracture risk

Chen P et al., 2008 J Bone Miner Res Open Access

Vertebral fractures are the most common osteoporotic fracture, and patients with prevalent vertebral fractures have a greater risk of future fractures. However, radiographically determined vertebral fractures are not identified as a distinct risk factor in the World Health Organization (WHO) fracture risk assessment tool. The objective of this study was to evaluate and compare potential risk factors including morphometric spine fracture status and the WHO risk factors for predicting 5-yr fracture risk. We hypothesized that spine fracture status provides prognostic information in addition to consideration of the WHO risk factors alone. A randomly selected, population-based community cohort of 2761 noninstitutionalized men and women > or =50 yr of age living within 50 km of one of nine regional centers was enrolled in the Canadian Multicentre Osteoporosis Study (CaMOS), a prospective and longitudinal cohort study following subjects for 5 yr. Prevalent and incident spine fractures were identified from lateral spine radiographs. Incident nonvertebral fragility fractures were determined by an annual, mailed fracture questionnaire with validation, and nonvertebral fragility fracture was defined by investigators as a fracture with minimal trauma. A model considering the WHO risk factors plus spine fracture status provided greater prognostic information regarding future fracture risk than a model considering the WHO risk factors alone. In univariate analyses, age, BMD, and spine fracture status had the highest gradient of risk. A model considering these three risk factors captured almost all of the predictive information provided by a model considering spine fracture status plus the WHO risk factors and provided greater predictive information than a model considering the WHO risk factors alone. The use of spine fracture status along with age and BMD predicted future fracture risk with greater simplicity and higher prognostic accuracy than consideration of the risk factors included in the WHO tool.

Bone Mineral Density · Measurement

Association between change in BMD and fragility fracture in women and men

Berger C et al., 2008 J Bone Miner Res Open Access

Our objective was to estimate the relationship between longitudinal change in BMD and fragility fractures. We studied 3635 women and 1417 men 50-85 yr of age in the Canadian Multicentre Osteoporosis Study who had at least two BMD measurements (lumbar spine, femoral neck, total hip, and trochanter) within the first 5 yr of the study and fragility fractures (any, main, forearm/wrist, ribs, hip) within the first 7 yr. Multiple logistic regression was used to model the relationship between baseline BMD, BMD change, and fragility fractures. We found that, among nonusers of antiresorptives, independent of baseline BMD, a decrease of 0.01 g/cm(2)/yr in total hip BMD was associated with an increased risk of fragility fracture with ORs of 1.15 (95% CI: 1.01; 1.32) in women and 1.34 (95% CI: 1.02; 1.78) in men. The risk of fragility fractures in subgroups such as fast losers and those with osteopenia was better estimated by models that included BMD change than by models that included baseline BMD but excluded BMD change. Although the association between baseline BMD and fragility fractures was similar in users and nonusers of antiresorptives, the association was stronger in nonusers compared with users. These results show that BMD change in both men and women is an independent risk factor for fragility fractures and also predicts fracture risk in those with osteopenia. The results suggest that BMD change should be included with other variables in a comprehensive fracture prediction model to capture its contribution to osteoporotic fracture risk.

Osteoporosis · Diagnosis and Treatment

The impact of incident fractures on health-related quality of life: 5 years of data from the Canadian Multicentre Osteoporosis Study

Papaioannou A et al., 2008 Osteoporos Int

Using prospective data from the Canadian Multicentre Osteoporosis Study (CaMos), we compared health utilities index (HUI) scores after 5 years of follow-up among participants (50 years and older) with and without incident clinical fractures. Incident fractures had a negative impact on HUI scores over time. This study examined change in health-related quality of life (HRQL) in those with and without incident clinical fractures as measured by the HUI. The study cohort was 4,820 women and 1,783 men (50 years and older) from the CaMos. The HUI was administered at baseline and year 5. Participants were sub-divided into incident fracture groups (hip, rib, spine, forearm, pelvis, other) and were compared with those without these fractures. The effects of both time and fracture type on HUI scores were examined in multivariable regression analyses. Men and women with hip fractures, compared to those without, had lower HUI measures that ranged from -0.05 to -0.25. Both women and men with spine fractures had significant deficits on the pain attributes (-0.07 to -0.12). In women, self-care (-0.06), mobility and ambulation (-0.05) were also negatively impacted. Women with rib fractures had deficits similar to women with spine fractures, and these effects persisted over time. In men, rib fractures did not significantly affect HUI scores. Pelvic and forearm fractures did not substantially influence HUI scores. The HUI was a sensitive measure of HRQL change over time. These results will inform economic analyses evaluating osteoporosis therapies.

Fracture Risk · Risk Factors

The effects of depot medroxyprogesterone acetate and intrauterine device use on fracture risk in Danish women

Vestergaard P et al., 2008 Contraception

Depot medroxyprogesterone acetate (DMPA) use may be associated with an increased risk of fractures; however, nothing is known about the risk associated with intrauterine contraceptive device (IUD) use. Case-control study. All women with a fracture (n=64,548) in the year 2000 in Denmark served as cases. For each case, three age-matched controls were randomly drawn from the general population (n=193,641). Exposure was present or previous DMPA or IUD use (only IUD coated with hormones, not those coated solely with copper). Adjustments were made for confounders. DMPA use seemed to be associated with an increased risk of fractures [odds ratio (OR)=1.44, 95% confidence interval (CI): 1.01-2.06], while IUD use appeared to be associated with a decreased risk of fractures (OR=0.75, 95% CI: 0.64-0.87). DMPA use may cause an increased risk of fracture. However, the fact that use of DMPA is rare in Danish women and the lack of baseline data including smoking status and BMI does not allow causal inferences to be made. Likewise, the seemingly decreased risk of fractures with IUD use is probably not a pharmacological effect but rather the effect of residual confounding related to nonincluded confounders regarding lifestyle.

Fracture Risk · Risk Factors

Fracture risk in very young women using combined oral contraceptives

Vestergaard P et al., 2008 Contraception

Little is known on fracture risk in young women using oral contraceptives. Case-control study (64,548 cases, 193,641 controls). Overall, no major association with risk of fracture was present. Only in a few age groups a limited increase (OR 1.1-1.5) was seen in those using low average doses (less than one tablet per day - i.e., intermittent use). Neither 20 nor >or=30 mcg per day of ethinylestradiol was associated with risk of fractures, while changing from 20 to >or=30 mcg per day or vice versa was associated with a limited increase in fracture risk (OR 1.1-1.4) in some age groups. In general, use of oral contraceptives in young women did not seem to be associated with an increased risk of fractures. The isolated increase seen in some strata with low average doses may be linked to factors associated with discontinuation of oral contraceptives rather than pharmacological effects.

Fracture Risk · Risk Factors

Geographic variation of bone mineral density and selected risk factors for prediction of incident fracture among Canadians 50 and older

Langsetmo L et al., 2008 Bone Open Access

Striking geographic variation in the incidence of osteoporotic fracture has been shown in national and international studies. The contributing risk factors for this variation are not fully understood. To determine the geographic variation of bone mineral density (BMD) values, prevalent low-trauma fracture, prior falls, and vertebral deformity and to determine how this variation is related to the geographic variation of incident low-trauma fracture. We studied incident fracture among 2484 men and 6093 women ages 50 and older from CaMos, a randomly-selected population-based longitudinal cohort recruited from within 50 kilometers of nine cities across Canada. Analyses included up to an eight-year follow-up. Estimates of fracture incidence are all age-standardized and given per 1000 person-years and CI denotes confidence interval. Among men, the lowest incidence of low-trauma fracture was 3.2 (95% CI: 1.1-7.5) in Quebec and the highest was 11.9 (95% CI: 7.1-18.6) in Calgary, compared with an overall incidence of 7.2 (95% CI: 5.8-8.7). Among women, the lowest incidence of low-trauma fracture was 11.5 (95% CI: 8.5-15.1) in Halifax and the highest was 18.5 (95% CI: 14.6-23.3) in Calgary, compared with an overall incidence of 15.3 (95% CI: 14.1-16.7). The regional variation in low-trauma fractures was similar to variation in hip fracture incidence among women (Pearson correlation, r=0.46 to 0.76) but not men (r=-0.06 to 0.05). We noted significant geographic variation in the prevalence of low BMD, as defined by BMD T-score< or =-2.5, however this variation was not directly related to low-trauma fractures or other risk factors. Furthermore, a model including age, BMD, falls, vertebral deformity, and prior clinical fracture was a good predictor of geographic variation of low-trauma fracture incidence in both men (r=0.66) and women (r=0.84). For both men and women, the burden of low-trauma fracture is not related to the prevalence of osteoporosis as defined by BMD, but is related to a more comprehensive assessment of fracture risk including the following: age, BMD, falls, prior fracture, and vertebral deformity.

Fracture Risk · Prevention

Effectiveness of antiresorptives for the prevention of nonvertebral low-trauma fractures in a population-based cohort of women

Langsetmo LA et al., 2008 Osteoporos Int Open Access

Observational studies are needed to quantify real-life effectiveness of antiresorptive therapy in the prevention of clinical fractures. Antiresorptive therapies were associated with an overall 32% reduction in low-trauma nonvertebral fracture risk among women 50 and older. Effectiveness may be lower among older women and those without risk factors. Randomized controlled trials have shown that antiresorptive therapies reduce the risk of fracture in selected populations, but further study is needed to quantify their real-life effectiveness. The study objective was to determine the association between antiresorptive use and low-trauma nonvertebral fracture in women 50 and older. The design was a retrospective nested case-control study (density-based sampling) within the Canadian Multicentre Osteoporosis Study. There were 5,979 eligible women with 453 cases and 1,304 matched controls. The current use of antiresorptives was associated with a decreased risk of fracture with OR = 0.68, 95% CI: 0.52-0.91; where OR is the adjusted odds ratio and CI is the confidence interval. Subgroup analysis yielded OR = 0.61, 95% CI: 0.42-0.89 for ages 50-74; OR = 0.76, 95% CI: 0.50-1.17 for ages 75+; OR = 0.58, 95% CI: 0.40-0.83 for those with a major risk factor; and OR = 0.92; 95% CI: 0.59-1.42 for those without a major risk factor. Major risk factors were prevalent low-trauma fracture, vertebral deformity (grade 2+), and BMD T-score < or = -2.5. Antiresorptive therapy is associated with a clinically important reduction in low-trauma nonvertebral fracture risk among community-dwelling women aged 50 and older. Antiresorptive therapy may be less effective for women 75 and older and women without major risk factors.

Bone Mineral Density · Measurement

Change in bone mineral density as a function of age in women and men and association with the use of antiresorptive agents

Berger C et al., 2008 CMAJ Open Access

Measurement of bone mineral density is the most common method of diagnosing and assessing osteoporosis. We sought to estimate the average rate of change in bone mineral density as a function of age among Canadians aged 25-85, stratified by sex and use of antiresorptive agents. We examined a longitudinal cohort of 9423 participants. We measured the bone mineral density in the lumbar spine, total hip and femoral neck at baseline in 1995-1997, and at 3-year (participants aged 40-60 years only) and 5-year follow-up visits. We used the measurements to compute individual rates of change. Bone loss in all 3 skeletal sites began among women at age 40-44. Bone loss was particularly rapid in the total hip and was greatest among women aged 50-54 who were transitioning from premenopause to postmenopause, with a change from baseline of -6.8% (95% confidence interval [CI] -7.5% to -4.9%) over 5 years. The rate of decline, particularly in the total hip, increased again among women older than 70 years. Bone loss in all 3 skeletal sites began at an earlier age (25-39) among men than among women. The rate of decline of bone density in the total hip was nearly constant among men 35 and older and then increased among men older than 65. Use of antiresorptive agents was associated with attenuated bone loss in both sexes among participants aged 50-79. Interpretation: The period of accelerated loss of bone mineral density in the hip bones occurring among women and men older than 65 may be an important contributor to the increased incidence of hip fracture among patients in that age group. The extent of bone loss that we observed in both sexes indicates that, in the absence of additional risk factors or therapy, repeat testing of bone mineral density to diagnose osteoporosis could be delayed to every 5 years.

Osteoporosis · Diagnosis and Treatment

The osteoporosis care gap in men with fragility fractures: the Canadian Multicentre Osteoporosis Study

Papaioannou A et al., 2007 Osteoporos Int Open Access

We examined osteoporosis diagnosis/treatment in 2,187 community dwelling men age 50+. After five years in the study, 90% of men with fragility fractures remained undiagnosed and untreated for osteoporosis. The need to treat fragility fractures is well established in guidelines, and these numbers represent an important care gap. Whether physicians in the community are recognizing and appropriately treating osteoporosis and fragility fractures in men remains unknown. We examined the rate of diagnosis and treatment in community dwelling men participating in the Canadian Multicentre Osteoporosis Study (CaMos). Between February 1996 and September 2002, 2,187 participants were recruited from nine sites across Canada and prospectively followed. Information on osteoporosis diagnosis, fractures, medications were collected annually by a detailed questionnaire. DXA examination of lumbar spine (L1-4) and hip were conducted at baseline and year five. Diagnosis and treatment in men with clinical fragility fractures was low: at baseline and year five only 2.3% and 10.3% of men with a clinical fracture reported an osteoporosis diagnosis, respectively. At year five, 90% of men with a clinical fragility fracture were untreated. Hip fractures were the most commonly treated (37.5% by year five). A diagnosis of osteoporosis resulted in greater treatment: 67% of participants with diagnosed osteoporosis were treated with a bisphosphonate and 87% were taking calcium and/or vitamin D (year five). In this population-based study, both a diagnostic and therapeutic gap existed between knowledge and practice related to fragility fractures and osteoporosis in men aged >or=50 years.

Osteoporosis · Diagnosis and Treatment

Fragility fractures and bone mineral density in HIV positive women: a case-control population-based study

Prior J et al., 2007 Osteoporos Int

This Canadian study of bone health showed that HIV+ women were more likely to have had fragility fractures (OR 1.7) but had BMD values that were not different than women from a national population-based cohort. Given that 17.5 million women globally are HIV-infected and living longer on anti-retroviral therapy (ART+), it is essential to determine whether they are at risk for osteoporosis as is currently assumed. Assessment of osteoporosis risk factors and lifetime low-trauma (fragility) fracture history used a common interviewer-administered questionnaire and phantom-adjusted bone mineral density (BMD). This study compared HIV+ Canadian women with ageand region-matched control women (1:3) from a national population-based study of osteoporosis. One hundred and thirty-eight HIV+ women (100 ART+, 38 ART-) were compared with 402 controls. There were no differences in age (37.7 vs. 38.0 years), BMI (25.0 vs. 26.2), family history of osteoporosis, exercise history, alcohol or calcium intakes, age at menarche, oral contraceptive use or parity. HIV+ cases included more Aboriginal and Black women (12.5% and 16.2 vs. 2% and 1%, respectively), smoked and used injection drugs (53%) more, were more often treated with glucocorticoids, had oligomenorrhea, and reported 10-kg weight cycling. Significantly more HIV+ women reported lifetime fragility fractures (26.1% vs. 17.3; OR 1.7, 95% CI 1.1, 2.6). HIV+ and control women did not differ in spine 1.0 +/- 0.12 vs.1.0 +/- 0.14 g/cm(2) (diff. 0.0, 95% CI -0.27, 0.27) or total femur 0.91 +/- 0.15 vs. 0.93 +/- 0.12 g/cm(2) (diff 0.02, 95% CI +0.005, -0.045). HIV+ women reported significantly more past osteoporotic fractures than population-based controls despite normal BMD. Research is needed to assess bone microarchitecture and develop a reliable fracture risk assessment tool for HIV+ women.

Fracture Risk · Risk Factors

Changes to osteoporosis prevalence according to method of risk assessment

Richards JB et al., 2007 J Bone Miner Res

The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk. Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy. We examined how the application of such absolute risk classification systems influences the prevalence of those considered to be at high risk for osteoporotic fracture and compared these systems to one based solely on BMD. Using 6646 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, randomly selected, population-based cohort, we assessed three different systems for determining prevalence of high risk for osteoporotic fracture: a BMD-based system; a simplified risk factor system incorporating age, sex, BMD, and two clinical risk factors; and a comprehensive system, incorporating age, sex, BMD, and seven clinical risk factors. The 10-year absolute risks of incident fragility fracture were compared across systems using three different high-risk thresholds. The prevalence of a T score < or = -2.5 was 18.8% (95% CI: 17.7-19.9%) in women and 3.9% (95% CI: 3.0-4.7%) in men. Using a 15% 10-year risk of fracture threshold, the prevalence of women at high risk increased to 46.9% (95% CI: 45.4-48.4) and 42.5% (95% CI: 41.1-43.9) when the comprehensive and simplified risk factor classification systems were used, respectively. Using a 25% 10-year absolute risk threshold, the prevalence of high risk was similar to that of the BMD-based system, whereas the 20% threshold gave intermediate rates. All thresholds analyzed resulted in an increased prevalence of older women at high risk for fracture, whereas only the 15% 10-year risk of fracture threshold resulted in an increase in the prevalence of men at high risk. The application of risk factor-based systems results in an increased prevalence of older women at high risk. The prevalence of individuals at high risk may increase with changes to the methods used to determine those who are eligible for therapy. These data have important implications for the pattern of care and costs of treating osteoporotic fractures.

Fracture Risk · Risk Factors

Effect of selective serotonin reuptake inhibitors on the risk of fracture

Richards JB et al., 2007 Arch Intern Med

Depression and osteoporotic fractures are common ailments among elderly persons. Selective serotonin reuptake inhibitors (SSRIs) are frequently used in the treatment of depression in this population, and the association between daily SSRI use and fragility fractures is unclear. Our objective was to examine the effect of daily SSRI use on the risk of incident clinical fragility fracture. A population-based, randomly selected, prospective cohort study of 5008 community-dwelling adults 50 years and older, followed up over 5 years for incident fractures. Clinical fragility fractures were classified as minimal trauma fractures that were clinically reported and radiographically confirmed. The risk of fragility fracture associated with daily SSRI use was determined while controlling for relevant covariates. Daily SSRI use was reported by 137 subjects. After adjustment for many potential covariates, daily SSRI use was associated with substantially increased risk of incident clinical fragility fracture (hazard rate, 2.1; 95% confidence interval, 1.3-3.4). Daily SSRI use was also associated with increased odds of falling (odds ratio, 2.2; 95% confidence interval, 1.4-3.5), lower bone mineral density at the hip, and a trend toward lower bone mineral density at the spine. These effects were dose dependent and were similar for those who reported taking SSRIs at baseline and at 5 years' follow-up. Daily SSRI use in adults 50 years and older remained associated with a 2-fold increased risk of clinical fragility fracture after adjustment for potential covariates. Depression and fragility fractures are common in this age group, and the elevated risk attributed to daily SSRI use may have important public health consequences.

Hormones and Bone · Estrogen and Bone

FSH and bone--important physiology or not?

Prior JC, 2006 Trends Mol Med

For many years, osteoporosis in women was equated with estrogen deficiency. The recent articles by Zaidi and colleagues offer a new challenge to the estrogen-deficiency-osteoporosis hypothesis by showing that follicle-stimulating hormone (FSH) stimulates osteoclastic bone resorption perhaps through tumor necrosis factor-alpha (TNF-alpha). These authors, however, neglected to mention bone abnormalities and high testosterone levels that were previously shown in FSH-receptor knockout and other modified mice. It is also possible that they have overemphasized potential relationships of these new data with human bone loss. Despite these fascinating data, the paradigm of FSH causing hypogonadal bone loss is not yet ready to displace the estrogen-deficiency-osteoporosis paradigm, although that model already faces considerable challenge.

Osteoporosis · Diagnosis and Treatment

What is the number of older Canadians needed to screen by measurement of bone density to detect an undiagnosed case of osteoporosis? a population-based study from CaMos

Sawka AM et al., 2006 J Clin Densitom

Routine bone mineral densitometry (BMD) screening has been recommended for women aged >or=65 yr (Osteoporosis Canada [OC], International Society for Clinical Densitometry [ISCD], Canadian and United States Task Forces on Preventative Healthcare, and National Osteoporosis Foundation) and for men >or=65 yr (OC) or >or=70 yr (ISCD). We estimated the number of older Canadians needed to screen (NNS) by BMD to detect an undiagnosed case of osteoporosis, using prospective, multicenter, population-based data from the Canadian Multicentre Osteoporosis Study (CaMos). We included participants aged >or=65 yr with baseline dual-energy X-ray absorptiometry (DXA) BMDs at the femoral neck and lumbar spine (L1-L4). Osteoporosis was defined by a T-score or=65 yr. The percentage prevalence and 95% confidence intervals were determined. In individuals aged >or=65 yr, the prevalence of osteoporosis was 25.6% in women (95% confidence interval, 24.0%, 27.3%) and 8.9% in men (7.3%, 10.8%). In 652 men aged >or=70 yr, the prevalence of osteoporosis was 11.3% (9.1%, 14.0%). Of the participants with BMD-defined osteoporosis, 76.6% of woman aged >or=65 yr (73.2%, 79.6%; 516 of 674 women), 93.4% of men aged >or=65 yr (86.4%, 96.9%; 85 of 91), and 93.2% of men >or=70 yr (84.9%, 97.0%; 68 of 73) were not aware of it. Thus, the minimum NNS by BMD testing to detect one previously undiagnosed case of osteoporosis in Canada is: 6 women aged >or=65 yr, 13 men aged >or=65 yr, and 10 men aged >or=70 yr.

Bone Mineral Density · Measurement

The effect of cyclooxygenase-2 inhibitors on bone mineral density: results from the Canadian Multicentre Osteoporosis Study

Richards JB et al., 2006 Osteoporos Int

The use of cyclooxygenase-2 (COX-2) inhibitors has been demonstrated to not only impair load-induced bone formation but also prevent menopause-associated bone loss. We hypothesized that COX-2 inhibitor use would be associated with increased bone mineral density (BMD) in postmenopausal women not using estrogen therapy and, conversely, with decreased BMD in men. The Canadian Multicentre Osteoporosis Study is a longitudinal, randomly selected, population-based community cohort. We present data from men (n=2,004) and postmenopausal women age 65 and older (n=2,776) who underwent a BMD measurement and structured interview in the 5th year of the study. The outcome measure was percent difference in BMD (g/cm(2)). Daily COX-2 inhibitor use was reported by 394 subjects. In men, daily use of COX-2 inhibitors was associated with a lower BMD at all hip sites, with a percent difference of -3.1% [95% confidence interval (CI), -6.0, -0.3] between users and nonusers at total hip. In postmenopausal women not using estrogen replacement therapy, daily COX-2 inhibitor use was associated with higher BMD at most sites [percent difference at total hip: +3.0% (95% CI, 0.3, 5.8)]. These effects appeared to be dose-dependent. COX-2 inhibitor use was associated with a lower BMD in men and, on the other hand, with a higher BMD in postmenopausal women not using estrogen replacement therapy. Men who have used COX-2 inhibitors may wish to seek BMD measurement to assess their fracture risk. However, COX-2 inhibitors may have utility in postmenopausal women if bone-selective analogs can be developed.

Fracture Risk · Risk Factors

Oral contraceptive use and risk of fractures

Vestergaard P et al., 2006 Contraception

Prior studies have suggested that oral contraceptives (OCs) may be associated with an increased fracture risk. However, the previous studies have only performed a limited adjustment for other potential risk factors. Subjects and methodsAll women with a fracture (n=64,548) in the year 2000 in Denmark served as cases. For each case, three age-matched controls were randomly drawn from the general population (n=193,641). Exposure was use of OCs between January 1, 1996, and December 31, 2000. Adjustments were made for use of other drugs, pregnancy, prior fracture, other diseases and social variables. In the unadjusted analysis, use of OCs in low dose was associated with a small increase in overall fracture risk. However, upon adjustment, no increase in fracture risk could be demonstrated in any age or dose group. Oral contraceptives are not associated with an increase or a decrease in fracture risk. Any change in fracture risk may be due to confounders.

Bone Mineral Density · Peak Bone Mass

Progestogen-only contraception and bone mineral density: a systematic review

Curtis KM et al., 2006 Contraception Open Access

Questions have been raised about the effects of progestogen-only contraceptive use on bone health, particularly among young women who have not yet reached peak bone mass and perimenopausal women who may be starting to lose bone mass. We conducted a systematic review that evaluated the association between progestogen-only contraceptive use and fracture risk or bone mineral density (BMD). We identified 39 articles from MEDLINE and EMBASE, published through July 2005. One study reported that depot medroxyprogesterone acetate (DMPA) users were more likely to experience stress fractures than nonusers; this association was not statistically significant after controlling for baseline bone density. In cross-sectional studies, the mean BMD in DMPA users was usually below that of nonusers, but within 1 SD. In longitudinal studies, BMD generally decreased more over time among DMPA users than among nonusers, but women gained BMD upon discontinuation of DMPA. Limited evidence suggested that use of progestogen-only contraceptives other than DMPA did not affect BMD.

Osteoporosis · Diagnosis and Treatment

Health-related quality of life measurements in elderly Canadians with osteoporosis compared to other chronic medical conditions: a population-based study from the Canadian Multicentre Osteoporosis Study (CaMos)

Sawka AM et al., 2005 Osteoporos Int

The objective of this research was to determine the relative decrement in health-related quality of life, as measured by the health utilities index mark 3 (HUI3), in osteoporosis compared to other chronic medical conditions. The impact of chronic medical conditions other than osteoporosis on HUI3 measurements had been previously established in the 1996/1997 Canadian National Population Health Survey (NPHS). The Canadian Multicentre Osteoporosis Study (CaMos) is a national population-based study in which regional participants were randomly recruited, regardless of presence of osteoporosis. We analyzed data from participants aged > or = 65 years who completed a baseline HUI3 questionnaire and provided information on their medical history (n=3,750). We determined the ageand gender-adjusted mean decrement in HUI3 for several chronic medical conditions, including osteoporosis. The mean changes in HUI3 adjusted for age and gender (with 95% confidence intervals) were as follows: arthritis -0.10 (-0.11, -0.09), chronic obstructive pulmonary disease (COPD) -0.07 (-0.09, -0.05), diabetes mellitus -0.05 (-0.08, -0.03), heart disease -0.06 (-0.08, -0.04), hypertension -0.02 (-0.03, -0.01), and osteoporosis -0.08 (-0.11, -0.06), respectively (model r2=0.17; P<0.0001). These findings were comparable to those observed in the NPHS, with the exception of osteoporosis, which had not been previously studied in this fashion. The decrement in HUI3 score seen in participants with osteoporosis was comparable to that observed in other chronic medical conditions, such as arthritis, COPD, diabetes mellitus or heart disease.

Fracture Risk · Risk Factors

Prior oral contraception and postmenopausal fracture: a Women's Health Initiative observational cohort study

Barad D et al., 2005 Fertil Steril

To test for the possible association of past oral contraceptive (OC) use and incident fracture after menopause. A prospective cohort of 93,725 postmenopausal women. Forty Women's Health Initiative (WHI) clinical centers across the United States. PATIENT(S): Ethnically diverse 93,725 volunteer postmenopausal women, 50 to 79 years old. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The main outcome was self-reported incident first fracture assessed prospectively by annual questionnaire. RESULT(S): The adjusted relative hazard (HR) for fracture among past OC users was 1.07 (95% CI, 1.01-1.15). Among women without any postmenopausal hormone treatment, past OC use for < or =5 years led to an HR of 1.15 (95% CI, 1.04-1.27) and for past OC use >5 years led to an HR of 1.09 (95% CI, 0.97-1.23) compared with never users. CONCLUSION(S): This study does not support the idea that past OC use protects against later fracture.

Fracture Risk · Risk Factors

Smoking and fracture risk: a meta-analysis

Kanis JA et al., 2005 Osteoporos Int

Smoking is widely considered a risk factor for future fracture. The aim of this study was to quantify this risk on an international basis and to explore the relationship of this risk with age, sex and bone mineral density (BMD). We studied 59,232 men and women (74% female) from ten prospective cohorts comprising EVOS/EPOS, DOES, CaMos, Rochester, Sheffield, Rotterdam, Kuopio, Hiroshima and two cohorts from Gothenburg. Cohorts were followed for a total of 250,000 person-years. The effect of current or past smoking, on the risk of any fracture, any osteoporotic fracture and hip fracture alone was examined using a Poisson model for each sex from each cohort. Covariates examined were age, sex and BMD. The results of the different studies were merged using the weighted beta-coefficients. Current smoking was associated with a significantly increased risk of any fracture compared to non-smokers (RR=1.25; 95% Confidence Interval (CI)=1.15-1.36). Risk ratio (RR) was adjusted marginally downward when account was taken of BMD, but it remained significantly increased (RR=1.13). For an osteoporotic fracture, the risk was marginally higher (RR=1.29; 95% CI=1.13-1.28). The highest risk was observed for hip fracture (RR=1.84; 95% CI=1.52-2.22), but this was also somewhat lower after adjustment for BMD (RR=1.60; 95% CI=1.27-2.02). Risk ratios were significantly higher in men than in women for all fractures and for osteoporotic fractures, but not for hip fracture. Low BMD accounted for only 23% of the smoking-related risk of hip fracture. Adjustment for body mass index had a small downward effect on risk for all fracture outcomes. For osteoporotic fracture, the risk ratio increased with age, but decreased with age for hip fracture. A smoking history was associated with a significantly increased risk of fracture compared with individuals with no smoking history, but the risk ratios were lower than for current smoking. We conclude that a history of smoking results in fracture risk that is substantially greater than that explained by measurement of BMD. Its validation on an international basis permits the use of this risk factor in case finding strategies.

Fracture Risk · Risk Factors

A family history of fracture and fracture risk: a meta-analysis

Kanis JA et al., 2004 Bone

The aims of the present study were to determine whether a parental history of any fracture or hip fracture specifically are significant risk factors for future fracture in an international setting, and to explore the effects of age, sex and bone mineral density (BMD) on this risk. We studied 34,928 men and women from seven prospectively studied cohorts followed for 134,374 person-years. The cohorts comprised the EPOS/EVOS study, CaMos, the Rotterdam Study, DOES and cohorts at Sheffield, Rochester and Gothenburg. The effect of family history of osteoporotic fracture or of hip fracture in first-degree relatives, BMD and age on all clinical fracture, osteoporotic fracture and hip fracture risk alone was examined using Poisson regression in each cohort and for each sex. The results of the different studies were merged from the weighted beta coefficients. A parental history of fracture was associated with a modest but significantly increased risk of any fracture, osteoporotic fracture and hip fracture in men and women combined. The risk ratio (RR) for any fracture was 1.17 (95% CI=1.07-1.28), for any osteoporotic fracture was 1.18 (95% CI=1.06-1.31), and for hip fracture was 1.49 (95% CI=1.17-1.89). The risk ratio was higher at younger ages but not significantly so. No significant difference in risk was seen between men and women with a parental history for any fracture (RR=1.17 and 1.17, respectively) or for an osteoporotic fracture (RR=1.17 and 1.18, respectively). For hip fracture, the risk ratios were somewhat higher, but not significantly higher, in men than in women (RR=2.02 and 1.38, respectively). A family history of hip fracture in parents was associated with a significant risk both of all osteoporotic fracture (RR 1.54; 95CI=1.25-1.88) and of hip fracture (RR=2.27; 95% CI=1.47-3.49). The risk was not significantly changed when BMD was added to the model. We conclude that a parental history of fracture (particularly a family history of hip fracture) confers an increased risk of fracture that is independent of BMD. Its identification on an international basis supports the use of this risk factor in case-finding strategies.

Fracture Risk · Risk Factors

Risk factors associated with incident clinical vertebral and nonvertebral fractures in postmenopausal women: the Canadian Multicentre Osteoporosis Study (CaMos)

Papaioannou A et al., 2004 Osteoporos Int

Utilizing data from the Canadian Multicentre Osteoporosis Study (CaMos), we examined the association between potential risk factors and incident vertebral and nonvertebral fractures. A total of 5,143 postmenopausal women were enrolled. Information collected during the study included data from the CaMos baseline and annually mailed fracture questionnaires, the Short Form 36 (SF-36), the Health Utilities Index, and physical measurements. Participants were followed for 3 years. Postmenopausal women were classified into four groups according to their incident fracture status since baseline: those without a new fracture; those with a new clinically recognized vertebral fracture; those with an incident nonvertebral fracture at the wrist, hip, humerus, pelvis, or ribs (main nonvertebral fracture group); and those with any new nonvertebral fracture (any-nonvertebral-fracture group). We performed multivariate Cox proportional hazard analysis using all possible risk factors to determine the association between risk factors and the time to the first minimal trauma fracture. Best predictive models were also determined using variables that were included in the full models. The Bayesian information criterion was used for model selection. For all analyses, relative risks and associated 95% confidence intervals were calculated. During the follow-up period, 34, 163, and 280 women developed a vertebral, a main nonvertebral, or any nonvertebral fracture, respectively. The best predictive models indicated that a five point lower quality of life as measured by the SF-36 physical component summary score was associated with relative risks of 1.21 (95% CI, 1.02 to 1.44), 1.17 (95% CI, 1.07 to 1.28), and 1.19 (95% CI, 1.11 to 1.27) for incident vertebral, main nonvertebral, and all nonvertebral fractures, respectively. In addition, for a one standard deviation (SD=0.12) lower femoral neck BMD, the relative risks for incident vertebral, main nonvertebral, and any nonvertebral fractures increased by 2.73 (95% CI, 1.74 to 4.28), 1.39 (95% CI, 1.06 to 1.82), and 1.34 (95% CI, 1.09 to 1.65), respectively. Furthermore, various anthropometric measures, disease conditions, and medications are associated with a new fracture. Identifying postmenopausal women at risk is important given that fracture prevention therapies are now available.

Fracture Risk · Risk Factors

A meta-analysis of previous fracture and subsequent fracture risk

Kanis JA et al., 2004 Bone

Previous fracture is a well-documented risk factor for future fracture. The aim of this study was to quantify this risk on an international basis and to explore the relationship of this risk with age, sex, and bone mineral density (BMD). We studied 15259 men and 44902 women from 11 cohorts comprising EVOS/EPOS, OFELY, CaMos, Rochester, Sheffield, Rotterdam, Kuopio, DOES, Hiroshima, and two cohorts from Gothenburg. Cohorts were followed for a total of 250000 person-years. The effect of a prior history of fracture on the risk of any fracture, any osteoporotic fracture, and hip fracture alone was examined using a Poisson model for each sex from each cohort. Covariates examined were age, sex, and BMD. The results of the different studies were merged by using the weighted beta-coefficients. A previous fracture history was associated with a significantly increased risk of any fracture compared with individuals without a prior fracture (RR = 1.86; 95% CI = 1.75-1.98). The risk ratio was similar for the outcome of osteoporotic fracture or for hip fracture. There was no significant difference in risk ratio between men and women. Risk ratio (RR) was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any fracture (8%) and for hip fracture (22%). The risk ratio was stable with age except in the case of hip fracture outcome where the risk ratio decreased significantly with age. We conclude that previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by measurement of BMD. Its validation on an international basis permits the use of this risk factor in case finding strategies.

Fracture Risk · Risk Factors

A meta-analysis of prior corticosteroid use and fracture risk

Kanis JA et al., 2004 J Bone Miner Res

The relationship between use of corticosteroids and fracture risk was estimated in a meta-analysis of data from seven cohort studies of approximately 42,000 men and women. Current and past use of corticosteroids was an important predictor of fracture risk that was independent of prior fracture and BMD. The aims of this study were to validate that corticosteroid use is a significant risk factor for fracture in an international setting and to explore the effects of age and sex on this risk. We studied 42,500 men and women from seven prospectively studied cohorts followed for 176,000 patient-years. The cohorts comprised the EPOS/EVOS study, CaMos, the Rotterdam Study, Dubbo Osteoporosis Epidemiology Study (DOES), and prospective cohorts at Sheffield, Rochester, and Gothenburg. The effect of ever use of corticosteroids, BMD, age, and sex on all fracture, osteoporotic fracture, and hip fracture risk alone was examined using Poisson regression in each cohort and for each sex. The results of the different studies were merged from the weighted beta coefficients. Previous corticosteroid use was associated with a significantly increased risk of any fracture, osteoporotic fracture, and hip fracture when adjusted for BMD. Relative risk of any fracture ranged from 1.98 at the age of 50 years to 1.66 at the age of 85 years. For osteoporotic fracture, the range of relative risk was 2.63-1.71, and for hip fracture 4.42-2.48. The estimate of relative risk was higher at younger ages, but not significantly so. No significant difference in risk was seen between men and women. The risk was marginally and not significantly upwardly adjusted when BMD was excluded from the model. The risk was independent of prior fracture. In the three cohorts that documented current corticosteroid use, BMD was significantly reduced at the femoral neck, but fracture risk was still only partly explained by BMD. We conclude that prior and current exposure to corticosteroids confers an increased risk of fracture that is of substantial importance beyond that explained by the measurement of BMD. Its identification on an international basis validates the use of this risk factor in case-finding strategies.

Osteoporosis · Diagnosis and Treatment

Chapter 33: Osteoporosis and Role of CrMS

Hilgers TW, 2004 The Medical and Surgical Practice of NaProTECHNOLOGY

Chronic anovulation and progesterone or estradiol deficiency identified through CrMS charting represent periods of suboptimal bone accrual in women of reproductive age, because both estradiol and progesterone contribute to skeletal maintenance -- estradiol through suppression of osteoclast activity and progesterone through osteoblast stimulation. NaProTECHNOLOGY uses longitudinal CrMS records of ovulatory status and hormone profiles as a bone-health risk screen, guiding cycle-synchronized bioidentical hormone replacement to restore normal estrogen-progesterone balance and potentially mitigate progression toward osteoporosis in women with chronic cycle-based endocrine deficiencies.

Bone Mineral Density · Measurement

Osteoporosis: What a clinician expects to learn from a patient's bone density examination

Lentle BC et al., 2003 Radiology

Osteoporosis has lately become recognized as an important disease on two accounts. On one hand, demographic change has resulted in a greatly increased and increasing burden of morbidity and mortality due to osteoporotic fracturing. On the other hand, lifestyle changes and preventive measures have become recognized as important factors in prevention of both osteoporosis and osteoporotic fractures, while several effective drug treatments have recently become available to treat osteoporosis by increasing bone density and reducing fracture incidence. Because bone density is, with age, the best predictor of fracture risk, its measurement has become central to the care of those potentially at risk. When a clinician refers a person for a bone density examination, the clinician should be concerned less with an "imaging diagnosis" than with the requirement that the laboratory has procedures in place for rigorous quality assurance and precision measurements, as well as for education of the staff involved. Implementation of these measures and an understanding of their clinical relevance in diagnosis and follow-up, as well as communication with clinicians in this context, are more important than any diagnostic insight that might be provided by "interpreting" a bone density study.

Osteoporosis · Diagnosis and Treatment

The association between osteoporotic fractures and health-related quality of life as measured by the Health Utilities Index in the Canadian Multicentre Osteoporosis Study (CaMos)

Adachi JD et al., 2003 Osteoporos Int

Osteoporotic fractures can be a major cause of morbidity. It is important to determine the impact of fractures on health-related quality of life (HRQL). A total of 3,394 women and 1,122 men 50 years of age and older, who were recruited for the Canadian Multicentre Osteoporosis Study (CaMos), participated in this cross-sectional study. Minimal trauma fractures of the hip, pelvis, spine, lower body (included upper and lower leg, knee, ankle, and foot), upper body (included arm, elbow, sternum, shoulder, and clavicle), wrist and hand (included forearm, hand, and finger), and ribs were studied. Participants with subclinical vertebral deformities were also examined. The Health Utilities Index Mark II and III Systems were used to assess HRQL. Past osteoporotic fractures varied in prevalence from 1.2% (pelvis) to 27.8% (lower body) in women and 0.3% (pelvis) to 29.3% (wrist) in men. Multivariate linear regression analyses [parameter estimates and corresponding 95% confidence intervals (CI)] indicated that minimal trauma fractures were negatively associated with HRQL and that this relationship depends on fracture type and gender. The multi-attribute scores for the Mark II system were negatively related to hip (-0.05; 95% CI: -0.09, -0.01), lower body (-0.02; 95% CI: -0.03, -0.000), and subclinical vertebral fractures (-0.02; 95% CI: -0.03, -0.00) for women. The multi-attribute scores for the Mark III system were negatively related to hip (-0.09; 95% CI: -0.14, -0.03) and rib fractures (-0.06; 95% CI: -0.11, -0.00) for women, and rib fractures (-0.06; 95% CI: -0.12, -0.00) for men. In conclusion, this study demonstrates a negative association between osteoporotic fractures and quality of life in both women and men.

Bone Mineral Density · Measurement

Associations among disease conditions, bone mineral density, and prevalent vertebral deformities in men and women 50 years of age and older: cross-sectional results from the Canadian Multicentre Osteoporosis Study

Hanley DA et al., 2003 J Bone Miner Res

This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.

Osteoporosis · Diagnosis and Treatment

Community-based exercise program reduces risk factors for falls in 65- to 75-year-old women with osteoporosis: randomized controlled trial

Carter ND et al., 2002 CMAJ

Exercise programs improve balance, strength and agility in elderly people and thus may prevent falls. However, specific exercise programs that might be widely used in the community and that might be "prescribed" by physicians, especially for patients with osteoporosis, have not been evaluated. We conducted a randomized controlled trial of such a program designed specifically for women with osteoporosis. We identified women 65 to 75 years of age in whom osteoporosis had been diagnosed by dual-energy X-ray absorptiometry in our hospital between 1996 and 2000 and who were not engaged in regular weekly programs of moderate or hard exercise. Women who agreed to participate were randomly assigned to participate in a twice-weekly exercise class or to not participate in the class. We measured baseline data and, 20 weeks later, changes in static balance (by dynamic posturography), dynamic balance (by a timed figure-eight run) and knee extension strength (by dynamometry). Of 93 women who began the trial, 80 completed it. Before adjustment for covariates, the intervention group tended to have greater, although nonsignificant, improvements in static balance (mean difference 4.8%, 95% confidence interval [CI] -1.3% to 11.0%), dynamic balance (mean difference 3.3%, 95% CI -1.7% to 8.4%) and knee extension strength (mean difference 7.8%, 95% CI -5.4% to 21.0%). Mean crude changes in the static balance score were -0.85 (95% CI -2.91 to 1.21) for the control group and 1.40 (95% CI -0.66 to 3.46) for the intervention group. Mean crude changes in figure-eight velocity (dynamic balance) were 0.08 (95% CI 0.02 to 0.14) m/s for the control group and 0.14 (95% CI 0.08 to 0.20) m/s for the intervention group. For knee extension strength, mean changes were -0.58 (95% CI -3.02 to 1.81) kg/m for the control group and 1.03 (95% CI -1.31 to 3.34) kg/m for the intervention group. After adjustment for age, physical activity and years of estrogen use, the improvement in dynamic balance was 4.9% greater for the intervention group than for the control group (p = 0.044). After adjustment for physical activity, cognitive status and number of fractures ever, the improvement in knee extension strength was 12.8% greater for the intervention group than for the control group (p = 0.047). The intervention group also had a 6.3% greater improvement in static balance after adjustment for rheumatoid arthritis and osteoarthritis, but this difference was not significant (p = 0.06). Interpretation: Relative to controls, participants in the exercise program experienced improvements in dynamic balance and strength, both important determinants of risk for falls, particularly in older women with osteoporosis.

Hormones and Bone · Adolescent Bone Accrual

Puberty and bone development

Saggese G et al., 2002 Best practice & research. Clinical endocrinology & metabolism

Puberty has a key role for bone development. Skeletal mass approximately doubles at the end of adolescence. The main determinants of pubertal gain of bone mass are the sex steroids, growth hormone and insulin-like growth factors (by their effects on bone and muscle mass), 1,25-dihydroxyvitamin D (by stimulating calcium absorption and retention) and muscle mass (by regulating modelling/remodelling thresholds). Calcium intake is an additional factor influencing bone formation. The interactions among these factors are undefined. The accrual of bone mass during puberty is a major determinant of peak bone mass and, thereby, of the risk of osteoporotic fractures during advanced age.

Hormones and Bone · Estrogen and Bone

Perimenopausal bone loss: more than estrogen depletion

Prior JC et al., 2001 J Bone Miner Res

To the Editor: In their recent article, "Characterization of Perimenopausal Bone Loss," Recker and colleagues present unique longitudinal bone mineral density (BMD) and hormonal data.1 We acknowledge the work involved in recruiting, motivating, and continuing to follow 75 women each for an average of 8 years. The data from this study are an important contribution to our knowledge of bone changes through the natural perimenopausal transition. Unfortunately, these authors have chosen to reduce the complex endocrinological and physiological changes of perimenopause2 to one idea—"estrogen deprivation." Our first concern is that "estrogen deprivation" or "depletion" is not an adequate concept with which to explain the rapid bone loss during perimenopause. The author's own data show that 50% of spinal BMD loss has occurred by 6 months before the final menstrual period at which time estradiol levels are not lower than in the so called "estrogen replete" group. In this study, perimenopausal bone loss appears to begin approximately 3 years before the final menstrual flow, which is about the time when menstrual cycles become irregular.3 Several other studies also show accelerated rates of perimenopausal bone loss.2, 4, 5 During these later phases of perimenopause, estradiol levels can be very high and certainly are not consistently low.2, 6, 7 If estradiol levels are not low in perimenopause, how can we explain the rapid bone loss? First, estradiol levels vary widely.2 Perhaps, acute drops in estradiol levels (often from abnormally high values) cause increased bone resorption much like that which has been shown to occur within seven days of premenopausal ovariectomy.8 A second possibility is that perimenopause causes psychosocial stress.9 Social stress coupled with high estradiol levels in men have been experimentally shown to cause increased cortisol levels10 that are known to be negative for bone. Finally, ovulatory changes that increase as women progress through perimenopause,11 are associated with accelerated cancellous bone loss, despite normal estradiol levels and regular cycles in premenopausal women.12 Replacement of luteal phases with cyclic progestin in a double-blind randomized study in premenopausal women with abnormal cycles caused an important positive change in spinal BMD.13 As a mechanism to allow use of all of their data, the authors labeled "estrogen replete" those women who continued to menstruate as well as those who started hormone therapy before menopause. It seems odd to us to combine data from three women who have undergone ovariectomy and seven women on exogenous hormone therapy with 10 preor perimenopausal women. The estrogen deprivation hypothesis has led the authors to overlook important physiological differences within this group. We request that the data for the 10 untreated preor perimenopausal women be provided and that we be told whether or not they continued to menstruate regularly. In women's life cycle, low levels of estrogen are as natural for menopausal women as for toddlers. To label menopause as a hormone deficiency condition is to ignore the normal hormonal pattern of women's lives. Recker and colleagues suggest that "hormone replacement therapy" should "begin as early as 2 years before the last menstrual period." Although we acknowledge that vasomotor symptoms commonly begin in perimenopause and have a very negative impact on quality of life, we suggest that progesterone would be a more appropriate therapy. Progesterone is truly low at this phase of perimenopause11 and is effective for night sweats/hot flushes. We fear that prescription of estrogen to women in late perimenopause may have negative consequences in both the short and the long-term. In the short term, it may exacerbate symptoms such as breast tenderness, headaches, and fluid retention. In the long term, having experienced side effects from estrogen treatment these women may refuse it when they are menopausal, a time when it has the potential to be valuable therapy. In summary, this important study is flawed because it relies on a clearly inadequate "estrogen deprivation" concept as the sole explanation for differences found in the prospective data from midlife women.

Bone Mineral Density · Peak Bone Mass

Oral contraceptive use and bone mineral density in premenopausal women: cross-sectional, population-based data from the Canadian Multicentre Osteoporosis Study

Prior JC et al., 2001 CMAJ

Positive and negative effects on bone mineral density (BMD) have been described as a result of the premenopausal use of oral contraceptives (OCs); increased fracture rates have also been reported. This study assessed the relation between OC use and BMD in a population-based, 9-centre, national sample of women aged 25-45 years. Premenopausal women who had been enrolled in the Canadian Multicentre Osteoporosis Study were classified as having ever been OC users (> or = 3 months) or as having never been OC users (0 to < 3 months). Data were obtained through extensive questionnaires and measuring of participants' weight, height and the BMD of lumbar vertebrae and the proximal femur. Of the sample of 524 women, whose mean age was 36.3 (standard deviation [SD] 5.9) years, 454 had used OCs; their mean age when they started using OCs was 19.8 (SD 3.5) years and the mean duration of use was 6.8 (SD 4.8) years. Women who had ever and those who had never used OCs showed no differences in age, age at menarche, parity, current calcium intake, exercise, body mass index (BMI), education, past irregular cycles or amenorrhea. OC users reported more alcohol and cigarette use and more use of medications to create regular cycles. Mean BMD values (adjusted for age, BMI and height) were 0.02-0.04 g/cm2 (that is, 2.3%-3.7%) lower in OC users, and were significantly lower in the spine and trochanter. The BMD of the spine in OC users was 1.03 (SD 0.12) g/cm2 versus 1.07 (SD 0.12) g/cm2 (95% confidence interval [CI] of difference -0.07 to -0.001) in those who had never used OCs. BMD was neither related to the duration of OC use nor to gynecological age at first use. Current and past users had similar BMD values. Interpretation: National, population-based data show lower BMD values for the trochanter and spine in premenopausal women who have used OCs compared with those who have never used OCs.

Osteoporosis · Diagnosis and Treatment

The influence of osteoporotic fractures on health-related quality of life in community-dwelling men and women across Canada

Adachi JD et al., 2001 Osteoporos Int

Health-related quality of life (HRQL) was examined in relation to prevalent fractures in 4816 community-dwelling Canadian men and women 50 years and older participating in the Canadian Multicentre Osteoporosis Study (CaMos). Fractures were of three categories: clinically recognized main fractures, subclinical vertebral fractures and fractures at other sites. Main fractures were divided and analyzed at the hip, spine, wrist/forearm, pelvis and rib sites. Baseline assessments of anthropometric data, medical history, therapeutic drug use, spinal radiographs and prevalent fractures were obtained from all participants. The SF-36 instrument was used as a tool to measure HRQL. A total of 652 (13.5%) main fractures were reported. Results indicated that hip, spine, wrist/forearm, pelvis and rib fractures had occurred in 78 (1.6%), 40 (0.8%), 390 (8.1%), 19 (0.4%) and 125 (2.6%) individuals, respectively (subjects may have had more than one main fracture). Subjects who had experienced a main prevalent fracture had lower HRQL scores compared with non-fractured participants. The largest differences were observed in the physical functioning (-4.0; 95% confidence intervals (CI): -6.0, -2.0) and role-physical functioning domains (-5.8; 95% CI: -9.5, -2.2). In women, the physical functioning domain was most influenced by hip (-14.9%; 95% CI: -20.9, -9.0) and pelvis (-18.1; 95% CI: -27.6, -8.6) fractures. In men, the role-physical domain was most affected by hip fractures (-35.7; 95% CI: -60.4, -11.1). Subjects who experienced subclinical vertebral fractures had lower HRQL scores than those without prevalent fractures. In conclusion, HRQL was lower in the physical functioning domain in women and the role-physical domain in men who sustained main fractures at the hip. Subclinical vertebral fractures exerted a moderate effect on HRQL.

Osteoporosis · Diagnosis and Treatment

Results of a 10 week community based strength and balance training programme to reduce fall risk factors: a randomised controlled trial in 65-75 year old women with osteoporosis

Carter ND et al., 2001 Br J Sports Med Open Access

To test the efficacy of a community based 10 week exercise intervention to reduce fall risk factors in women with osteoporosis. Static balance was measured by computerised dynamic posturography (Equitest), dynamic balance by timed figure of eight run, and knee extension strength by dynamometry. Subjects were randomised to exercise intervention (twice weekly Osteofit classes for 10 weeks) or control groups. The outcome in 79 participants (39 exercise, 40 control) who were available for measurement 10 weeks after baseline measurement is reported. After confounding factors had been controlled for, the exercise group did not make significant gains compared with their control counterparts, although there were consistent trends toward greater improvement in all three primary outcome measures. Relative to the change in control subjects, the exercise group improved by 2.3% in static balance, 1.9% in dynamic balance, and 13.9% in knee extension strength. A 10 week community based physical activity intervention did not significantly reduce fall risk factors in women with osteoporosis. However, trends toward improvement in key independent risk factors for falling suggest that a study with greater power may show that these variables can be improved to a level that reaches statistical significance.

Bone Mineral Density · Measurement

Evaluation of decision rules for referring women for bone densitometry by dual-energy x-ray absorptiometry

Cadarette SM et al., 2001 JAMA

Identification of women with low bone mineral density (BMD) is an important strategy in reducing the incidence of osteoporotic fractures. However, screening all women is not recommended. To assess the diagnostic properties of 4 decision rules--Simple Calculated Osteoporosis Risk Estimation (SCORE), Osteoporosis Risk Assessment Instrument (ORAI), Age, Body Size, No Estrogen (ABONE), and body weight less than 70 kg (weight criterion)--for selecting women for dual-energy x-ray absorptiometry (DXA) testing and to compare results with recommendations made in the National Osteoporosis Foundation (NOF) practice guidelines. DESIGN AND Analysis of data from the Canadian Multicentre Osteoporosis Study, a population-based community sample, collected from 9 study centers across Canada between February 1996 and September 1997. Postmenopausal women aged 45 years or older (N = 2365) without bone disease who had DXA data for the femoral neck, data to apply selection criteria, and who were not currently taking estrogens or who had been taking hormone replacement therapy for 5 or more years. Sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve of each of the 4 decision rules and the NOF guidelines for identifying women with a BMD T score of less than -1.0 SD, less than -2.0 SD, and no more than -2.5 SD at the femoral neck, and percentages of women recommended for testing, stratified by BMD level and age. The percent of women with a BMD T score less than -1, less than -2, and no more than -2.5 were 68.3%, 25.4%, and 10.0%, respectively. The AUROC curves were greatest using SCORE and ORAI. The sensitivity for identifying women with a BMD T score of less than -2.0 was 93.7% (95% confidence interval [CI], 91.8%-95.6%) using the NOF guidelines and was 97.5% (95% CI, 96.3%-98.8%), 94.2% (95% CI, 92.3%-96.1%), 79.1% (95% CI, 75.9%-82.3%), and 79.6% (95% CI, 76.4%-82.8%), respectively, using the SCORE, ORAI, ABONE, and weight criterion. However, the NOF guidelines also resulted in 74.4% (95% CI, 71.3%-77.6%) of women with a normal BMD (T score of -1.0 or higher) being tested compared with 69.2% (95% CI, 65.9%-72.5%), 56.3% (95% CI, 52.7%-59.8%), 35.8% (95% CI, 32.4%-39.2%), and 38.1% (95% CI, 34.6%-41.6%), respectively, using the 4 decision rules. Assessments suggest that ABONE and weight criterion are not useful case-finding approaches. The SCORE and ORAI decision rules are better than the NOF guidelines at targeting BMD testing in high-risk patients. The acceptability of these rules in clinical practice merits further investigation given their potential effect on the use of densitometry services.

Fracture Risk · Risk Factors

Influence of parity and lactation on hip fracture risk

Michaëlsson K et al., 2001 Am J Epidemiol

Several studies indicate that parity and lactation are associated with modest, short-term bone loss, but the long-term effect on osteoporotic fracture risk is uncertain. The authors therefore analyzed data from a population-based case-control study among Swedish postmenopausal women aged 50-81 years between October 1993 and February 1995. Mailed questionnaires and telephone interviews were used to collect data on 1,328 incident cases with hip fracture and 3,312 randomly selected controls. In age-adjusted analyses, the risk of hip fracture among all women was reduced by 10% per child (95% confidence interval (CI): 5, 14). After multivariate adjustment including body mass index as a covariate, the risk reduction was 5% per child (95% CI: 0, 10). Oral contraceptive use modified the association of parity with hip fracture risk. Among never users of oral contraceptives, the risk of hip fracture was reduced by 8% per child (95% CI: 2, 13), whereas among ever users of oral contraceptives, the risk was in the opposite direction, with an increase in risk by 19% per child (95% CI: 0, 41). After parity was considered, there was no association of duration of lactation period with fracture risk. The authors conclude that parity is modestly associated with a reduced hip fracture risk among women who had not used oral contraceptives previously.

Bone Mineral Density · Peak Bone Mass

Eating attitudes and habitual calcium intake in peripubertal girls are associated with initial bone mineral content and its change over 2 years

Barr SI et al., 2001 J Bone Miner Res

This 2-year prospective study examined associations among bone mineral acquisition and physical, maturational, and lifestyle variables during the pubertal transition in healthy girls. Forty-five girls, initially 10.5+/-0.6 years, participated. Body composition and bone mineral content (BMC) at the spine and total body (TB) were assessed at baseline and annually thereafter using dual-energy X-ray absorptiometry (DXA). Nutrient intakes were assessed using 3-day diet records and a calcium food frequency questionnaire (FFQ), physical activity by questionnaire, sexual maturation using Tanner's stages of breast and pubic hair maturation, growth by height and weight, and eating attitudes using the children's Eating Attitudes Test (Children's EAT). Mean children's EAT subscale scores (dieting, oral control [OC], and bulimia) were stable over time. Median split of OC subscale scores was used to form high and low OC groups. Groups had similar body composition, dietary intake, activity, and Tanner stage at baseline and 2 years. Using height, weight, and Tanner breast stage as covariates, girls with low OC scores had greater TB BMC at baseline (1452+/-221 g vs. 1387+/-197 g; p = 0.030) and 2 years (2003+/-323 g vs. 1909+/-299 g; p = 0.049) and greater lumbar spine (LS) BMC at 2 years (45.2+/-8.8 g vs. 41.2+/-9.6 g; p = 0.042). In multiple regression analysis, OC score predicted baseline, 2 years, and 2-year change in TB and spinal BMC, contributing 0.9-7.6% to explained variance. Calcium intake predicted baseline, 2 years, and 2-year change in TB BMC, explaining 1.6-5.3% of variance. We conclude that both OC and habitual calcium intake may influence bone mineral acquisition.

Osteoporosis · Diagnosis and Treatment

Estimation of the prevalence of low bone density in Canadian women and men using a population-specific DXA reference standard: the Canadian Multicentre Osteoporosis Study (CaMos)

Tenenhouse A et al., 2001 Osteoporos Int

The Canadian Multicentre Osteoporosis Study (CaMos) is a prospective cohort study which will measure the incidence and prevalence of osteoporosis and fractures, and the effect of putative risk factors, in a random sample of 10,061 women and men aged > or = 25 years recruited in approximately equal numbers in nine centers across Canada. In this paper we report the results of studies to establish peak bone mass (PBM) which would be appropriate reference data for use in Canada. These reference data are used to estimate the prevalence of osteoporosis and osteopenia in Canadian women and men aged > or = 50 years. Participants were recruited via randomly selected household telephone listings. Bone mineral density (BMD) of the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry using Hologic QDR 1000 or 2000 or Lunar DPX densitometers. BMD results for lumbar spine and femoral neck were converted to a Hologic base. BMD of the lumbar spine in 578 women and 467 men was constant to age 39 years giving a PBM of 1.042 +/- 0.121 g/cm2 for women and 1.058 +/- 0.127 g/cm2 for men. BMD at the femoral neck declined from age 29 years. The mean femoral neck BMD between 25 and 29 years was taken as PBM and was found to be 0.857 +/- 0.125 g/cm2 for women and 0.910 +/- 0.125 g/cm2 for men. Prevalence of osteoporosis, as defined by WHO criteria, in Canadian women aged > or = 50 years was 12.1% at the lumbar spine and 7.9% at the femoral neck with a combined prevalence of 15.8%. In men it was 2.9% at the lumbar spine and 4.8% at the femoral neck with a combined prevalence of 6.6%.

Osteoporosis · Diagnosis and Treatment

Vertebral fracture definition from population-based data: preliminary results from the Canadian Multicenter Osteoporosis Study (CaMos)

Jackson SA et al., 2000 Osteoporos Int

The Canadian Multicenter Osteoporosis Study is a large population-based prospective study of osteoporosis in the Canadian population. The study involves 9424 subjects, both male and female, from nine centers and seven regions of Canada. Each subject completed an extensive interview to obtain medical, demographic and lifestyle information, and was examined by dual-energy X-ray absorptiometry of the spine and hip, ultrasound of the heel and, for subjects over 50 years of age, lateral spine radiographs. Spinal morphometry of the initial radiographs was performed to determine the prevalence of vertebral deformity. A method is utilized to extract reference norms for vertebral shape from a subset of the population data, which is then used to categorize any deformity within the whole data set. Using 3 standard deviations (SD) as a limit of normality', the male prevalence of 21.5% was similar to the female prevalence of 23.5%. Using 4 SD this reduced to 7.3% and 9.3% respectively. The younger men (50-59 years) showed a higher prevalence of deformity than the women and a lower increase of prevalence with age. In the older age group (over 80 years) the female prevalence of 45% compared with 36% for the men using 3 SD (grade 1) to define the limit of normality. The female group presented with more severe deformities on average than the male group. This continuing study will provide longitudinal information regarding the development of osteoporosis and associated risk factors which will eventually be of use to develop public health policies.

Bone Mineral Density · Peak Bone Mass

Augmented trochanteric bone mineral density after modified physical education classes: a randomized school-based exercise intervention study in prepubescent and early pubescent children

McKay HA et al., 2000 J Pediatr

Of the few exercise intervention studies focusing on pediatric populations, none have confined the intervention to the scheduled physical education curriculum. To examine the effect of an 8-month school-based jumping program on the change in areal bone mineral density (aBMD), in grams per square centimeter, of healthy thirdand fourth-grade children. Ten elementary schools were randomized to exercise (n = 63) and control groups (n = 81). Exercise groups did 10 tuck jumps 3 times weekly and incorporated jumping, hopping, and skipping into twice weekly physical education classes. Control groups did regular physical education classes. At baseline and after 8 months of intervention, we measured aBMD and lean and fat mass by dual-energy x-ray absorptiometry (Hologic QDR-4500). Calcium intake, physical activity, and maturity were estimated by questionnaire. The exercise group showed significantly greater change in femoral trochanteric aBMD (4.4% vs 3.2%; P <.05). There were no group differences at other sites. Results were similar after controlling for covariates (baseline aBMD change in height, change in lean, calcium, physical activity, sex, and ethnicity) in hierarchical regression. An easily implemented school-based jumping intervention augments aBMD at the trochanteric region in the prepubertal and early pubertal skeleton.

Bone Mineral Density · Peak Bone Mass

Running and ovulation positively change cancellous bone in premenopausal women

Petit MA et al., 1999 Med Sci Sports Exerc

Exercise is understood to exert positive effects on bone. However cancellous bone has not been shown to increase with exercise. Previous results of our 1-yr observational prospective study in ovulatory women related 20% of the change in cancellous spinal bone mineral density (BMD), measured by quantitative computed tomography (QCT), to luteal phase length (the time from ovulation to menstruation, LL). The 66 women who documented exercise daily included normally active women (N = 23) and those who ran consistently or were increasing running in preparation for a marathon (N = 43). Exercise did not affect BMD change in the women as a whole. We re-evaluated those data to determine whether exercise-related effects on spinal cancellous BMD change in regularly cycling premenopausal women were related to ovulatory characteristics. The potential relationship of exercise to BMD change was reanalyzed by stratifying women into tertiles according to average LL documented by quantitative basal temperature analysis. Repeated-measures ANOVA indicated independent positive effects of both luteal length (P = 0.001) and activity (P = 0.041). The 11 runners with LL > 10.9 d had a nonsignificant 0.5% increase in lumbar BMD while the 15 who averaged short LL (<9.9 d) experienced a significant 3.6% loss. In the runners as a group, however, kilometers run per week was negatively related to BMD change throughout (r = -0.347, P = 0.024). These data are the first to indicate that, in women with regular cycles, luteal length and exercise independently and positively affect change in spinal cancellous BMD.

Hormones and Bone · Contraceptive Effects on Bone

Oral-contraceptive use and risk of hip fracture: a case-control study

Michaëlsson K et al., 1999 Lancet

Epidemiological studies indicate a protective effect of postmenopausal oestrogen therapy on the risk of osteoporotic fractures. Whether premenopausal oestrogen exposure in the form of oral contraceptives also reduces the risk of osteoporotic fractures remains uncertain. We did a population-based case control study of hip fracture among Swedish postmenopausal women, 50-81 years of age, through mailed questionnaires and telephone interviews. Of those women who were eligible, 1327 (82.5%) cases and 3312 (81.6%) randomly selected controls responded. Findings: 130 (11.6%) cases and 562 (19.1%) controls reported ever-use of oral contraceptives. Ever-use of oral contraceptives was associated with a 25% reduction in hip fracture risk (odds ratio 0.75 [95% CI 0.59-0.96]). Women who had ever used a high-dose pill (equivalent to > or = 50 microg ethinylestradiol per tablet) had a 44% lower risk for hip fracture than never-users (0.56 [0.42-0.75]). No overall trend was observed with duration of oral-contraceptive use, or time since last use. However, when making comparisons with women who have never used oral contraceptives, the odds ratios for hip-fracture were 0.69 (0.51-0.94) for use after age 40, 0.82 (0.57-1.16) for use at ages 30-39, and 1.26 (0.76-2.09) for use before age 30. Interpretation: Our results imply that in postmenopausal women, oral-contraceptive use late in reproductive life may reduce the risk of hip fracture, although we recognise the limitations of the case-control method.

Osteoporosis · Diagnosis and Treatment

Research Notes: The Canadian Multicentre Osteoporosis Study (CaMos): Background, Rationale, Methods

Kreiger N et al., 1999 Can. J. Aging

Relatively little is known about the factors in Canada which lead to osteoporosis and its concomitant fractures. The Canadian Multicentre Osteoporosis Study (CaMos) is a prospective cohort study which will estimate the incidence and prevalence of declining bone mass and fractures. The impact of osteoporosis in Canada will be assessed, including regional variation and the effect of various risk factors. The study will provide information for developing prevention programs. The cohort has been drawn from a random population-based sample of non-institutionalized men and women 25 years old or more and living within 50 km. of nine cities in Canada. Through telephone interviews 9,423 participants have been recruited. All answered an extensive questionnaire, and had physical measurements related to bone quality taken. This paper details the CaMos baseline and five-year follow-up protocol.

Bone Mineral Density · Peak Bone Mass

Spinal bone mineral density in premenopausal vegetarian and nonvegetarian women: cross-sectional and prospective comparisons

Barr SI et al., 1998 J Am Diet Assoc

To compare spinal bone mineral density (BMD) and 1-year BMD change between premenopausal vegetarian and nonvegetarian women. Cross-sectional comparison of spinal BMD at baseline and prospective comparison of a subsample. A western Canadian metropolitan area. Subjects/samples: Healthy vegetarian (n = 15 lacto-ovo-vegetarian, n = 8 vegan) and nonvegetarian (n = 22) women aged 20 to 40 years, with regular menstrual cycles and stable body weight completed baseline measurements. Twenty of these women (6 lacto-ovo-vegetarian, 5 vegan, 9 nonvegetarian) participated in repeat measurements at approximately 13 months. Statistical Analyses Performed: Descriptive statistics, independent sample and paired t tests, 1-way analysis of variance, correlation analysis, and stepwise multiple regression were used to compare groups and to assess associations with BMD. At baseline, subjects were 27.2 +/- 5.1 years old. Vegetarians had lower body mass index (21.1 +/- 2.3 vs 22.7 +/- 1.9, P < .05) and percent body fat (24.0 +/- 5.5% vs 27.4 +/- 5.1%, P < .05); they also tended to have lower BMD (1.148 +/- 0.111 g/cm2 vs 1.216 +/- 0.132 g/cm2, P = .06), although this was not apparent with weight as a covariate (P = .14). Baseline BMD was predicted by vitamin B-12 intake and total body fat (R2 = .24, P = .001). Participants in the follow-up differed only in their being older than nonparticipants. Over 1 year, mean BMD increased significantly (1.1%): by diet group, nonvegetarians' BMD increased but vegetarians' BMD was unchanged. No other monitored variables were associated with BMD change. Applications/ Vegetarian women should be aware of links between low BMD and low body weight/body fat, and should maintain adequate intakes of nutrients believed to affect BMD.

Hormones and Bone · Estrogen and Bone

Long-term effects of percutaneous estradiol on bone loss and bone metabolism in postmenopausal hysterectomized women

Devogelaer JP et al., 1998 Maturitas

To determine whether percutaneous estradiol (pE2) (1.5 mg/day) is able to counteract the postmenopausal bone loss in postmenopausal hysterectomized women, in a double-blind study versus oral estriol (E3) (2 mg/day). The bone mineral density of the lumbar spine (LS) and of the proximal femur (PF) was measured every 3 months by dual energy X-ray absorptiometry for 2 years in 43 hysterectomized postmenopausal women (21 in the E2 group and 22 in the E3 control group), and in a subset of patients for a 3rd year. The statistical analyses were performed on Macintosh using Stat View II. A significant bone loss of 1.2 (0.4%)% and of 1.3 (0.3)% per year was observed in the control group, respectively at LS and at PF, versus a significant gain of 1.2 (0.5)% per year in the treated group at the LS. No significant change at PF occurred in the treated group. In the 20 patients followed up for a 3rd year on pE2, an increase of 1.2 (0.9) and 2.5 (1.4)% at LS in the 12 former active group patients and the eight formerly control patients, respectively was seen. The same trend was observed at the proximal femur. pE2 (1.5 mg E2) is able to counteract the postmenopausal bone loss in hysterectomized women, whereas E3 (2 mg/day administered orally) is unable to maintain bone mass.

Fracture Risk · Risk Factors

Oral contraception and other factors in relation to hospital referral for fracture. Findings in a large cohort study

Vessey M et al., 1998 Contraception

There is good evidence that estrogens and progestogens have an important effect on bone metabolism. This article explores the relationship between oral contraceptive (OC) use and fractures occurring at various sites among the 17,032 participants in the Oxford-Family Planning Association contraceptive study, which now includes information accumulated during 310,000 woman-years of observation between 1968 and 1994. In total, 1308 women suffered at least one fracture during the follow-up period, which was largely confined to premenopausal years. When all fractures were combined, there was a modest, but highly significant trend (p < 0.001) of increasing risk with total duration of oral contraceptive use. In addition, there was statistically significant heterogeneity (p < 0.01) when overall fracture rates were examined in relation to recency of oral contraceptive use during the premenopausal lifespan. The highest relative risk (1.3, 95% CI 1.1-1.5) was for current or recent oral contraceptive users; however, viewed as a whole, no clear pattern of risk was apparent. Examination of the data for individual fracture sites (including the lower end of the radius/ulna) did not provide any evidence of a protective effect of oral contraceptive use. These results are closely similar to those reported from the Royal College of General Practitioners Oral Contraception Study in 1993. Estrogens and progestogens have an important effect on bone metabolism. The present study explored the relationship between oral contraceptive (OC) use and bone fractures in the cohort of 17,032 English and Scottish participants in the Oxford-Family Planning Association contraceptive study (1968-94). The analysis was based on the calculation of woman-years of observation terminated by referral for fracture or release from follow-up due to death, emigration, or short-term pill users reaching age 45 years. A total of 1308 women experienced at least one fracture during 310,000 woman-years of observation and there was a significant (p 0.001) positive relationship between age and fracture risk. Most common were fractures of the radius/ulna, tarsal/metatarsal bones, and ankle. When all fractures were combined, there was a significant (p 0.001) increasing risk with total duration of OC use. Also observed was a significant (p 0.01) heterogeneity when overall fracture rates were examined in relation to recency of OC use during the premenopausal lifespan. The highest relative risk (1.3; 95% confidence interval, 1.1-1.5) was recorded among current or recent OC users. There was about a 20% increase in the overall risk of fracture in women who had used OCs at any time compared with never-users. Overall, however, no clear pattern of risk emerged. These results are similar to those reported in the 1993 Royal College of General Practitioners OC Study. It is assumed that the increased fracture risk in OC users results from life-style characteristics of such women rather than a direct effect of OCs on bone.

Hormones and Bone · Estrogen and Bone

Premenopausal ovariectomy-related bone loss: a randomized, double-blind, one-year trial of conjugated estrogen or medroxyprogesterone acetate

Prior JC et al., 1998 J Bone Miner Res

The purpose of this study was to contrast the effects of conventional estrogen treatment with medroxyprogesterone on cancellous and cortical bone change in the first year following premenopausal ovariectomy. This 1-year double-blind randomized therapy trial was stratified by osteoporosis family history and performed in an academic medical center and community hospitals. Premenopausal women 45 +/- 5 years old, postovariectomy for benign diseases were provided 600 mg/day of calcium and randomized to daily therapy with conjugated equine estrogen (CEE, 0.6 mg) or medroxyprogesterone (MPA, 10 mg). The primary outcome variable was spinal quantitative computed tomography (QCT) bone density change over 1 year with additional outcomes of dual-energy X-ray absorptiometry (DXA) of proximal femur (FN), whole body (WB), and spine segment (WBS) and N-telopeptide, bone-specific alkaline phosphatase, and other bone marker, hormonal, and weight changes. Results in the 33 women completing the study, whose initial bone densities were normal (QCT 133 mg/cm3, femoral neck 0.94 g/cm2, whole body DXA 1.13 g/cm2), showed annual QCT loss during CEE therapy of -11.5 mg/cm3 (p < 0.0007) and MPA bone loss of -19.7 mg/cm3 (p < 0.0001). Losses were marginally greater on MPA than CEE (p = 0.04). Extremely high postovariectomy (5 days) and pretreatment resorption markers (> 3 SD above premenopausal normal levels) were significantly related to bone loss. Across the year, resorption decreased during CEE but increased on MPA treatment. Significant DXA bone losses were prevented by CEE treatment (-1.4% FN, -.4% WB, and -1.5% WBS, all NS). However, DXA bone loss was not prevented by MPA treatment (-5% FN, -2.8% WB, and -6.1% WBS, all p < 0.03). Average weight gain was significant (+ 3.2 +/- 4.0 kg) and greater on CEE than MPA (+ 4.7 vs. + 2.0 kg, p = 0.049). In conclusion, CEE therapy did not prevent significant 8% cancellous spinal bone loss in the first year following premenopausal ovariectomy, despite supplementation with 600 mg/day of calcium, good control of vasomotor symptoms, and nearly 5 kg of gain in weight. Significant DXA bone loss, however, was prevented by CEE, but not by MPA therapy. These unexpected results were statistically related to high bone resorption following ovariectomy, which CEE suppressed but MPA did not. Bone formation markers increased during MPA therapy but were unchanged during CEE therapy.

Hormones and Bone · Contraceptive Effects on Bone

Bone mineral changes in young women with hypothalamic amenorrhea treated with oral contraceptives, medroxyprogesterone, or placebo over 12 months

Hergenroeder AC et al., 1997 Am J Obstet Gynecol

The objectives of this study were to assess (1) whether treatment with oral contraceptives, in comparison with medroxyprogesterone and placebo, improved bone mineral in women with hypothalamic amenorrhea and (2) whether treatment with medroxyprogesterone, in comparison with placebo, improved bone mineral in women with hypothalamic oligomenorrhea. The study was a randomized, controlled clinical trial. Twenty-four white women, aged 14 to 28 years, with hypothalamic amenorrhea or oligomenorrhea were prospectively enrolled for a 12-month intervention period. Amenorrheic subjects were randomized to receive oral contraceptives, medroxyprogesterone, or placebo. Oligomenorrheic subjects were randomized to receive medroxyprogesterone or placebo. Bone mineral was measured by dual-energy x-ray absorptiometry at baseline and at 6 and 12 months. In amenorrheic subjects spine and total body bone mineral measurements at 12 months were greater in the oral contraceptive group than in the medroxyprogesterone and placebo groups when baseline bone mineral measurements, body weight, and age were controlled for (p < or = 0.05). There were no differences in hip bone mineral calcium and bone mineral density measurements at 12 months among the three groups. In oligomenorrheic subjects there was no detectable improvement in bone mineral associated with medroxyprogesterone use. This study supports the hypothesis that oral contraceptive use in women with hypothalamic amenorrhea will improve lumbar spine and total body bone mineral.

Bone Mineral Density · Measurement

EXERCISE-ASSOCIATED CANCELLOUS BONE CHANGE: POSITIVE EFFECT OF OVULATION 1116

Petit MA et al., 1997 Medicine & Science in Sports & Exercise

Current concepts suggest that normal estrogen levels are necessary for exercise to have an osteogenic effect on bone. In a population of running and sedentary women Prior et al. (NEJM, 1990) have shown that consistent ovulation is necessary to prevent spinal cancellous bone loss. Change in spinal bone mineral density was measured by quantitative computed tomography (QCT) in running and sedentary women over one year, along with prospective documentation of dietary, menstrual cycle, hormonal, and exercise variables. Of the 66 women studied only 12 remained ovulatory throughout the year. Forty-two women were runners of which 6 were consistently ovulatory. We hypothesized that ovulation would interact with an exercise effect on cancellous bone. Analysis of the 42 runners showed an average loss in bone of 1.8%. Luteal phase index (r = 0.509) and average progesterone (r = 0.381) were correlated with change in QCT, but not estrogen, calcium, or any other hormonal, dietary, or morphometric variable. There was a negative association between change in QCT and number of km run/week (r = -0.319). In the 12 consistently ovulatory women, average cancellous bone increased in runners(≈2%) and decreased in nonrunners (N) by ≈1% (seefig.). These data are the first to show an increase in purely cancellous bone with moderate levels of aerobic activity. The results suggest that the presence of consistently ovulatory cycles, and thus progesterone in addition to estrogen, may be necessary for an osteogenic effect of low impact exercise (running) on cancellous bone.

Fracture Risk · Risk Factors

Menstrual and reproductive factors and hip fractures in post menopausal women

Parazzini F et al., 1996 Maturitas

We analyzed the relationship between menstrual and reproductive history and risk of hip fractures in post-menopausal women using data from an Italian case-control study. Cases were 206 post-menopausal women admitted for fractures of the hip proximal femur to a network of teaching and general hospitals in Milan, Italy. The comparison group consisted of 590 post-menopausal women admitted to the same network of hospitals for acute, non-neoplastic, non-hormone-related conditions, other than traumatic or orthopedic disorders. Odds ratios (OR) of hip fracture were derived from unconditional multiple logistic regression. No relation emerged between risk of hip fractures and age at menarche, lifelong menstrual cycle pattern and age at menopause. In comparison with women with age at menopause > or = 53 years, the multivariate OR of hip fractures were 1.2, 1.1, 1.2 and 0.5 in women with menopause at 50-52, 45-49, 40-44 and before 40 years (X2(1) trend 0.21). In comparison with nulliparae, the estimated age-adjusted OR was 0.6 (95% confidence interval, CI, 0.4-0.9) for parous women, but the multivariate estimate was not significant (OR 0.8, 95% CI 0.6-1.3) and the multivariate trend in risk with number of births was not significant either. No relation emerged between hip fractures and age at first and last birth, and history of abortions. This study found no relevant influence of menstrual and reproductive factors on the risk of hip fractures in post-menopausal women. However, this is not in contrast with the observation of a short-term effect of menopause and more in general. female hormone levels on osteoporosis and hence on hip fractures.

Hormones and Bone · Estrogen and Bone

Effect of estriol on bone loss in postmenopausal Japanese women: a multicenter prospective open study

Minaguchi H et al., 1996 J Obstet Gynaecol Res

To assess the effects of oral estriol on the bone mineral density (BMD) and bone metabolism in postmenopausal women. Seventy-five natural postmenopausal women with a BMD of more than 10% below the peak bone density were treated for 50 weeks with 2 mg/day estriol (E3) cyclically and 0.8 g/day of calcium lactate continuously. BMDs at L2-L4 were measured by dual energy X-ray absorptiometry (DXA). The BMD increased 1.79% (p < 0.01 vs. pretreatment) after 50 weeks, accompanied with decrease of biochemical markers of bone turnover. With regard to climacteric symptoms, Kupperman's menopausal index improved (p < 0.01 vs. pretreatment) after 5 weeks of treatment. As to the incidence of adverse events genital bleeding was observed in only 8.0% of the subjects. Endometrial histology and cytology showed neither abnormalities nor hyperplasia during and after the treatment. Estriol prevented postmenopausal bone loss and improved climacteric symptoms effectively with low incidence of genital bleeding.

Fracture Risk · Risk Factors

Risk factors, falls, and fracture of the distal forearm in Manchester, UK

O'Neill TW et al., 1996 J Epidemiol Community Health Open Access

To determine the risk factors associated with fracture of the distal forearm, and to evaluate the influence of falls on these risks. This was a case-control study. Manchester, UK. The cases were 62 white women aged 45-82 years who had sustained a fracture of the distal forearm and had attended local hospitals. Two control groups were studied - 50 women who had fallen onto the hand but had not sustained a fracture (recruited from the same source as those with fracture) and 116 women randomly selected from primary care age and sex registers in the catchment area of the hospitals. Both cases and controls were sent a letter inviting them to take part in the study. Data were collected by questionnaire completed by an interviewer. MAIN Compared with the population control group, those with fracture were more likely to walk at a brisk pace (odds ratio (OR) = 3.5; 95% confidence interval (CI) 1.3, 9.6) though they had undertaken less physical activity at home or work on a daily basis throughout life (OR = 0.4; 95% CI 0.2, 0.9). The risk associated with brisk walking was less marked when the cases were compared with fall controls. Other lifestyle factors including calcium intake, smoking, and alcohol consumption were not associated with fracture. Analysis of gynaecological and hormonal factors suggested that compared with population controls, those with fracture of the distal forearm had had fewer fertile years (OR = 0.4; 95% CI 0.1, 0.9) and were less likely to have used oral contraceptives (OR = 0.3; 95% CI 0.1, 0.9). The data highlight the need for caution when advising middle aged and elderly subjects about exercise. Such advice should be combined with practical information about the prevention of falls. Hormonal factors seem to be additional determinants of fracture. Other lifestyle interventions seem unlikely to play an important part in preventing distal forearm fracture.

Bone Mineral Density · Measurement

Ovulatory premenopausal women lose cancellous spinal bone: a five year prospective study

Prior JC et al., 1996 Bone

Healthy premenopausal women with regular cycles are believed to be increasing or maintaining bone density. However, few studies have prospectively documented spinal cancellous bone, the bone that changes rapidly in response to reproductive hormones, in this population. Furthermore, our previous one-year study documented that 24% of the one-year bone change by quantitative computed tomography (QCT) was related to subclinical ovulatory disturbances (short luteal phase and non-ovulation) in the presence of regular menstrual cycles. The purpose of this study was to document the cancellous bone change over five years in this initially ovulatory, premenopausal cohort of 66 healthy women. Thirty-seven women, who continued to be premenopausal and have regular cycles, completed this five-year study. Those enrolled differed only by being older and weighing less than those who could not be contacted (n = 19) or who declined to participate (n = 10). Documentation of current ovulatory characteristics was obtained for at least three cycles in 27 women. At the five-year assessment, the volunteers were 40.6 (range 26-47) years old, weighed 58.5 (41-77) kg, and were 160.9 (149-174) cm in height. All were premenopausal, healthy, nonsmokers with regular menstrual cycles (mean 27.7, range 24-33 days). Six women with intervening events (such as pregnancy or use of oral contraceptives) had interval (12 to 60 months) QCT changes similar to the remaining 31 (-7.98 vs. -4.92 mg/cm, p = 0.1, respectively). Mean five-year QCT was 143.0 +/- 20.2 mg/cm, whereas the initial mean value was 151.9 +/- 20.1 mg/cm. Significant QCT loss over five years (-8.9 +/- 6.2 mg/cm) (95% Cl -6.9 to -11.0) correlated with QCT change in the first year (r = 0.629, p < 0.001). First-year change was not related to the subsequent four-year interval change (r = -0.056, p = 0.74), however. Five-year QCT change was not related to age, weight, osteoporosis family history, estimated calcium intake, or exercise, but did correlate with year one luteal index (luteal/cycle length) (r = 0.339, p = 0.043). Significant cancellous spinal bone loss occurs in healthy, ovulatory premenopausal women, and is influenced by subclinical disturbances of ovulation.

Hormones and Bone · Estrogen and Bone

Low and conventional dose transdermal oestradiol are equally effective at preventing bone loss in spine and femur at all post-menopausal ages

Evans SF et al., 1996 Clin Endocrinol (Oxf)

We wished to appraise the effectiveness of hormone replacement therapy (HRT) in early (< 67 years) and late (> 67 years) post-menopausal women referred to a metabolic outpatient clinic for assessment of their bone status. Because older women often experience side-effects with conventional HRT, a low dose preparation (Estraderm 25) was also compared with conventional HRT (Estraderm 50). Since all patients were symptomatic, the investigation was open and not placebo controlled. Patients were offered HRT and told about the two dosages. If they wished to use HRT, allocation of dosage was made randomly unless there were reasons to use a specific dose. One hundred and ninety-six women were studied over 1 or 2 years with 80 reaching 3 years of treatment. Patients were divided into those under 67 years and those over 67 years at the start of treatment. Each group was further divided into those taking Estraderm 25 and those taking Estraderm 50 with norethisterone if appropriate. Bone mineral density (BMD) was measured (DXA, Hologic) at the lumbar spine and femoral neck at 0 year (196 patients), at 1 year (169 patients), at 2 years (139 patients) and at 3 years (80 patients). Patients losing bone were expressed as those whose 3 year BMD was lower than initial or as those whose BMD at 3 years had fallen by more than twice the coefficient of variation for that site (non-responders). In lumbar spine, BMD increased maximally in the first year in all groups and the gain was maintained after 3 years. The change was similar whether patients were divided by age or dosage. For those on Estraderm 25, mean change after 3 years was 8.1 +/- 6.8% and on Estraderm 50, 9.0 +/- 8.3% (combined 8.7 +/- 7.8%). Only 3.9% of patients were non-responders at the lumbar spine after 3 years. At femoral neck, changes were significant at 3 years only in the Estraderm 25 > 67 years and Estraderm 50 < 67 years groups and averaged 2.3 +/- 5.4% for all patients. At the femoral neck, 10.4% of patients were non-responders after 3 years. Percentage change of BMD over 3 years at lumbar spine correlated with that at the femoral neck (r = 0.56). Percentage change of BMD at lumbar spine over 3 years correlated with menopausal age (r = 0.295). No relation was found between dosage of Estraderm/kg body weight and response of BMD at either site. Transdermal oestrogen is effective at preventing bone loss in the spine at all post-menopausal ages and is capable of doing this in low dosage. Prevention of bone loss at the femoral neck is less certain and the average change in BMD over 3 years was significantly lower (P < 0.001) than in the lumbar spine. Use of Estraderm 50 is not associated with a greater response of bone mass and there was no evidence of an increasing BMD response as oestradiol dosage/kg body weight increased.

Hormones and Bone · Estrogen and Bone

Cyclic medroxyprogesterone treatment increases bone density: a controlled trial in active women with menstrual cycle disturbances

Prior JC et al., 1994 Am J Med

Bone loss occurs in young women who experience amenorrhea or ovulatory disturbances. The purpose of this study was to determine whether bone loss could be prevented by simulating a more normal hormonal pattern, using treatment with cyclic medroxyprogesterone, with or without calcium supplementation, in physically active women with disturbed menstruation. This study was a 1-year randomized, double-blind, placebo-controlled trial. Women who were stratified by menstrual cycle disturbance were randomized into four groups. The outcome variable was the change in spinal bone density measured by dual energy techniques. A large metropolitan area. Sixty-one healthy, normal-weight physically active premenopausal women aged 21 to 45 years who experienced amenorrhea, oligomenorrhea, anovulation, or short luteal phase cycles completed the study. Therapies were cyclic medroxyprogesterone (10 mg/day for 10 days per month) and calcium carbonate (1,000 mg/day of calcium) in four groups: (A) (n = 16) cyclic medroxyprogesterone plus calcium carbonate; (B) (n = 16) cyclic medroxyprogesterone with calcium placebo; (C) (n = 15) placebo medroxyprogesterone with active calcium; or (D) (n = 14) both medroxyprogesterone and calcium placebos. The initial bone density (mean = 1.12 g/cm2) did not differ by group (P = 0.85). The 1-year bone density change was strongly related to treatment with medroxyprogesterone (P = 0.0001) and weakly to calcium (P = 0.072) treatment. Bone density increased significantly (+1.7% +/- 0.5%, +/- SEM, P = 0.004) in the medroxyprogesterone-treated groups (A and B), did not change in the calcium-treated group (C) (-0.7% +/- 0.6%, P = 0.28), and decreased on both placebos (D) (-2.0% +/- 0.6%, P = 0.005). Cyclic medroxyprogesterone increased spinal bone density in physically active women experiencing amenorrhea or ovulatory disturbances. POTENTIAL Amenorrhea, oligomenorrhea, anovulation, and short luteal phase cycles are common in premenopausal women and associated with spinal bone loss occurring at a stage of life when bone density would normally be stable or increasing. This controlled trial shows a significant gain in bone in women in the cyclic medroxyprogesterone intervention group, whereas those subjects in the placebo group lost bone. Calcium supplementation appeared to be helpful but did not reach statistical significance. The implications of these findings for the prevention of osteoporosis warrant further investigation.

Osteoporosis · Diagnosis and Treatment

Osteoporosis risk factors, gynaecological history and fractures in perimenopausal women--the results of the baseline postal enquiry of the Kuopio Osteoporosis Risk Factor and Prevention Study

Tuppurainen M et al., 1993 Maturitas

The Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) Study examines the risk factors of osteoporosis, the relationship of risk factors to bone density and fractures, as well as the possibility to prevent bone loss by administering certain hormones. The baseline postal enquiry in 1989 was sent to all the 14,220 women aged 47-56 years residing in the Kuopio Province, Finland. The questionnaire included questions about their gynaecological history, physical exercise and smoking habits, calcium intake, body weight and height, history of bone fractures, health disorders, their current and previous use of drugs, as well as their willingness to participate in bone densitometry and in a clinical hormone trial. The response rate was 92.8%. In all, 56% reported some previous use of female hormones. Strong contraindications for oestrogen replacement therapy were found in 9.3% of the women. Almost half of the respondents reported lack of regular physical exercise, 11.9% were smokers, and 17.0% reported a calcium intake from milk products of less than 500 mg daily. The incidence of fractures increased steadily with age. The incidence of premenopausal fractures within the last 10 years was 7.65 per 1000 person/years and that of postmenopausal fractures was 17.40 per 1000 person/years (P = 0.000). The effect of menopause on fracture incidence was stronger than the effect of a 5-year age increase. Of the respondents, 84.4% were willing to participate in bone densitometry and 68.3% for long-term prevention of osteoporosis with oestrogen.

Hormones and Bone · Estrogen and Bone

Effect of transdermal 17 beta-estradiol and oral conjugated equine estrogens on biochemical parameters of bone resorption in natural menopause

Reginster JY et al., 1993 Calcif Tissue Int

To evaluate and compare the effects or oral and transdermal estrogen replacement therapy on biochemical markers of bone resorption in early postmenopausal women. Controlled, randomized group comparison. Outpatient clinic for menopausal women and research into osteoporosis. Sixty healthy women menopausal for less than 5 years and who had never received any medications interfering with bone metabolism. The 60 women were randomly allocated to 3 months therapy with either oral conjugated estrogens (0.625 mg/day) (n = 28) or transdermal estradiol (50 micrograms/day) (n = 32) in cyclical combination with medroxyprogesterone acetate (5 mg/day). Traditional (urinary calcium/creatinine and hydroxyproline/creatinine) and the new specific (urinary pyridinoline/creatinine and deoxypyridinoline/creatinine) markers of bone resorption were determined before and after 3 months of treatment. In both groups, circulating levels of estrone and estradiol were significantly (P < 0.001) increased during treatment. In women treated with oral conjugated equine estrogens, urinary calcium/creatinine and hydroxyproline/creatinine ratios were significantly (P < 0.05) reduced. Pyridinoline/creatinine ratio fell from 69.1 (4) [mean (SEM)] to 50 (4) mumol/mumol (P < 0.01) and deoxypyridinoline/creatinine ratio fell from 10.8 (1) [mean (SEM)] to 8.3 (0.8) mumol/mumol (P < 0.01). In the group treated with transdermal estradiol, urinary hydroxyproline/creatinine ratio was significantly (P < 0.05) reduced. Pyridinoline/creatinine ratio fell from 66.3 (4) [mean (SEM)] to 46.2 (3) mumol/mumol (P < 0.01) and deoxypyridinoline/creatinine ratio fell from 11.5 (1.5) [mean (SEM)] to 7.7 (0.6) mumol/mumol (P < 0.01). There were no differences between the evolution of the biochemical variables in the two groups. These results suggest that oral conjugated equine estrogens and transdermal estradiol, in the given doses, are equally effective in reducing postmenopausal bone resorption.

Fracture Risk · Risk Factors

Oral contraceptive pill use and fractures in women: a prospective study

Cooper C et al., 1993 Bone

It has been suggested that use of the oral contraceptive pill by women confers protection against osteoporosis later in life. However, cross-sectional studies of bone density among pill users have yielded discrepant results. We therefore investigated the relationship between pill use and subsequent occurrence of fracture in a cohort of 46,000 women enrolled in the Royal College of General Practitioners Oral Contraception Study during 482,083 person-years of follow-up. Fracture risk was lower among multiparous women, non-smokers, and those of lower socio-economic class. The risk of subsequent fractures among the women who had ever used the oral contraceptive pill was significantly greater than that among women who had never used it (relative risk 1.20, 95% confidence intervals 1.08-1.34) after adjustment for these variables. When the analysis was confined to forearm fractures, no significant effect of pill use on fracture risk was detected. Although the study only includes limited observation of older women to date, these data do not support the hypothesis that pill use protects women against the occurrence of osteoporotic fractures in later life.

Hormones and Bone · Estrogen and Bone

Low-dosage micronized 17 beta-estradiol prevents bone loss in postmenopausal women

Ettinger B et al., 1992 Am J Obstet Gynecol

With the use of a double-blind, randomized, dose-ranging design, we tested during an 18-month period the degree of protection against postmenopausal bone loss afforded by micronized 17 beta-estradiol in dosages of 0.5, 1.0, and 2.0 mg. All subjects received supplementation to ensure a minimum of 1500 mg calcium daily. Fifty-one subjects completed at least 1 year of follow-up bone density measurements by quantitative computed tomography and by single- and dual-photon absorptiometry. In the placebo group spinal trabecular bone density decreased 4.9% annually (p less than 0.001), whereas in those taking micronized 17 beta-estradiol bone density tended to increase (annual increases of 0.3% in the 0.5 mg micronized 17 beta-estradiol group, 1.8% in the 1.0 mg micronized 17 beta-estradiol group, and 2.5% in the 2.0 mg micronized 17 beta-estradiol group). After completing the double-blind phase, 41 subjects completed an additional 18 months of follow-up while taking 1.0 mg micronized 17 beta-estradiol. During this time one third of the subjects were randomly assigned to discontinue calcium supplements. Among those who previously received placebo, trabecular bone density increased 4.3% annually, whereas among those who had used micronized 17 beta-estradiol, trabecular bone density response was inversely related to the dosage previously used. Additionally and independently, the level of calcium intake showed a statistically significant correlation with the change in spinal trabecular bone density (r = 0.37, p = 0.02). We conclude that micronized 17 beta-estradiol has a continuous skeletal dose-response effect in the range of 0.5 to 2.0 mg and that calcium intake positively modifies the skeletal response to 1.0 mg micronized 17 beta-estradiol.

Hormones and Bone · Estrogen and Bone

Spinal bone loss and ovulatory disturbances

Prior JC et al., 1990 N Engl J Med

Osteoporosis develops in women with estrogen deficiency and amenorrhea who lose bone at an accelerated rate. It is not known to what extent bone loss differs between ovulatory women with regular menstrual cycles who are training intensely and those who are sedentary. We measured the density of cancellous spinal bone from the 12th thoracic vertebra to the 3rd lumbar vertebra by quantitative computed tomography on two occasions one year apart in 66 premenopausal women 21 to 42 years of age. All the women had two consecutive ovulatory cycles immediately before entering the study. Twenty-one women were training for a marathon, 22 ran regularly but less intensively, and 23 had normal levels of activity. The lengths of the women's menstrual cycles and luteal phases, diet, exercise levels, and hormonal levels were also determined. We defined ovulatory disturbances as anovulatory cycles and cycles with short luteal phases. The mean (+/- SD) spinal bone density in the 66 women decreased 3.0 +/- 4.8 mg per cubic centimeter per year (2.0 percent per year) (P less than 0.001). Amenorrhea did not develop in any woman during the year of observation (only 2.7 percent of the cycles were greater than 36 days long). Ovulatory disturbances occurred in 29 percent of all cycles, however. Bone loss was strongly associated with these disturbances (r = 0.54, 24 percent of the variance). The 13 women who had anovulatory cycles lost bone mineral at a rate of 6.4 +/- 3.8 mg per cubic centimeter per year (4.2 percent per year). The women training for a marathon had menstrual cycles similar to those of the women in the other two groups. Decreases in spinal bone density among women with differing exercise habits correlated with asymptomatic disturbances of ovulation (without amenorrhea) and not with physical activity.

Hormones and Bone · Estrogen and Bone

Progesterone as a bone-trophic hormone

Prior JC, 1990 Endocr Rev

Experimental, epidemiological, and clinical data indicate that progesterone is active in bone metabolism. Progesterone appears to act directly on bone by engaging an osteoblast receptor or indirectly through competition for a glucocorticoid osteoblast receptor. Progesterone seems to promote bone formation and/or increase bone turnover. It is possible, through estrogen-stimulated increased progesterone binding to the osteoblast receptor, that progesterone plays a role in the coupling of bone resorption with bone formation. A model of the interdependent actions of progesterone and estrogen on appropriately-"ready" cells in each bone multicellular unit can be tied into the integrated secretions of these hormones within the ovulatory cycle. Figure 5 is an illustration of this concept. It shows the phases of the bone remodeling cycle in parallel with temporal changes in gonadal steroids across a stylized ovulatory cycle. Increasing estrogen production before ovulation may reverse the resorption occurring in a "sensitive" bone multicellular unit while gonadal steroid levels are low at the time of menstrual flow. The bone remodeling unit would then be ready to begin a phase of formation as progesterone levels peaked in the midluteal phase. From this perspective, the normal ovulatory cycle looks like a natural bone-activating, coherence cycle. Critical analysis of the reviewed data indicate that progesterone meets the necessary criteria to play a causal role in mineral metabolism. This review provides the preliminary basis for further molecular, genetic, experimental, and clinical investigation of the role(s) of progesterone in bone remodeling. Much further data are needed about the interrelationships between gonadal steroids and the "life cycle" of bone. Feldman et al., however, may have been prophetic when he commented; "If this anti-glucocorticoid effect of progesterone also holds true in bone, then postmenopausal osteoporosis may be, in part, a progesterone deficiency disease."

Bone Mineral Density · Measurement

Bone mineral density in women with endometriosis before and during ovarian suppression with gonadotropin-releasing hormone agonists or danazol

Tummon IS et al., 1988 Fertil Steril

Lumbar bone mineral density (BMD) was evaluated by dual photon absorptiometry (DPA) in 38 women with laparoscopically diagnosed and staged endometriosis. DPA was performed before and at the completion of 26 weeks of treatment with either gonadotropin releasing hormone agonist (GnRHa) or danazol. Twenty-five women received GnRHa either nasally or subcutaneously and 13 women received danazol 200 mg four times daily by mouth. During treatment amenorrhea and suppressed estradiol levels were observed in all patients. Each patient took a supplement of oral calcium 1 gm daily. DPA (reproducibility +/- 1.5%) was read by a single observer unaware of the treatment assignment of the patient. The mean (+/- standard error) of the entire group prior to treatment was 98.8% +/- 0.03% of a control population of women from the same geographic area matched for race, age, and weight. At the completion of treatment, BMD was slightly decreased in the GnRHa group and marginally increased in the danazol group but neither change was significant. Women with endometriosis have lumbar BMD in the normal range and ovarian suppression with either GnRHa or danazol produces no significant change in BMD.

Fracture Risk · Risk Factors

Dialysis encephalopathy and osteomalacic bone disease: a case-controlled study

Prior JC et al., 1982 Am J Med

Nine patients on long-term hemodialysis with dialysis encephalopathy were studied, with sex matched control subjects for eight of the patients. Each patient with dialysis encephalopathy and control subject were contemporaries in a similar dialysis environment. Rib and other fractures were found in excess in the patients with dialysis encephalopathy (p less than 0.005 and p less than 0.01). These patients had less radiographic hyperparathyroid bone disease, and no more osteopenia as measured by metacarpal thickness than did their control counterparts. Severe osteomalacia was documented by bone biopsy in four of te patients. In a retrospective review of clinical, biochemical and pharmacologic differences, the patients with dialysis encephalopathy were significantly older at the start of dialysis (45.6 years versus 38.6 years, p less than 0.02) and had higher mean concentrations of blood urea nitrogen (BUN) and lower serum hemoglobin in the first year of dialysis than the control subjects. Blood pressure weight, creatinine, calcium, phosphate, alkaline phosphatase and a number of transfusions did not differ significantly. There was no difference in prescribed vitamin D and elemental aluminum in phosphate binders. This study demonstrates that patients with dialysis encephalopathy had more rib fractures without more parathyroid or osteopenic bone disease than did the control subjects and suggests that the etiology of dialysis encephalopathy and osteomalacia is multifactorial.

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Nutrition and Metabolic Health · Dietary Patterns

Vitamin D intakes among women living with and without HIV in Canada

King EM et al., 2023 HIV Med

Patterns of vitamin D intake are relatively unexplored among women living with HIV, despite its importance for women's health. We compared vitamin D dietary and supplement intakes in women with HIV and population-based national controls and investigated barriers to intake. In this case-control study, women with HIV in the Children and Women: AntiRetrovirals and Markers of Aging (CARMA) cohort were matched with Canadian Multicentre Osteoporosis Study (CaMos) controls. Participants were queried for vitamin D in dairy consumption, supplementation/dosage, and sociodemographic variables. We assessed barriers to supplementation and factors associated with dietary intake by regression modelling. Ninety-five women living with HIV were age-matched to 284 controls. Women with HIV had lower income and bone mineral density and were more likely to smoke, take multiple medications and be non-white. Vitamin D dietary intake was lower in women living with HIV versus controls [0.76 vs. 1.79 μg/day; adjusted odds ratio (aOR) for greater than or equal to median intake 0.29 (0.12-0.61), p = 0.002], but any supplementation was higher [62.2% vs. 44.7%; aOR = 3.44 (95% CI: 1.16-11.00), p = 0.03]. Total vitamin D intake was similar between groups. Smoking was associated with no supplementation; non-white ethnicity and low income were related to lower dietary intake. Women living with HIV showed lower dietary vitamin D intake but higher supplementation rates, suggesting that care providers are promoting supplementation. Women living with HIV who smoke, have low incomes and are non-white may particularly benefit from targeted efforts to improve vitamin D intake.

Nutrition and Metabolic Health · Dietary Patterns

Pivotal role of boron supplementation on bone health: A narrative review

Rondanelli M et al., 2020 Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) Open Access

Boron is a trace element that plays an important role in numerous biological functions, including calcium metabolism, growth and maintenance of bone tissue. However, there are still no precise indications regarding a possible role of boron supplementation, and its amount of supplementation, to maintain bone health. So the aim of this narrative review was to consider the state of the art on the effectiveness of boron supplementation (alone or with other micronutrients) on growth and maintenance of bone in humans through control of calcium, vitamin D and sex steroid hormone metabolism in order to suggest a daily dosage of boron supplementation. This review included 11 eligible studies: 7 regarding the supplementation with boron alone and 4 regarding supplementation with boron and other nutrients. Despite the number of studies considered being low, the number of subjects studied is high (594) and the results are interesting. The studies considered in this narrative review have evaluated the positive effectiveness on bone, in humans, through control of calcium, vitamin D and sex steroid hormone metabolism, considering a dietary supplementation of 3 mg/day of boron (alone or with other nutrients); this supplementation is demonstrably useful to support bone health (in order to prevent and maintain adequate bone mineral density), also considering the daily dose of 3 mg is much lower than the Upper Level indicated by EFSA in the daily dose of 10 mg.

Nutrition and Metabolic Health · Eating Disorders and Underfueling

Prevalence of Female Athlete Triad Risk Factors and Iron Supplementation Among High School Distance Runners: Results From a Triad Risk Screening Tool

Skorseth P et al., 2020 Orthopaedic journal of sports medicine

Investigations of the female athlete triad (Triad) in high school athletes have found that 36% had low energy availability, 54% had menstrual abnormalities, and 16% had low bone mineral density (BMD). Limited data are available showing the prevalence of these risk factors in high school distance runners or regarding best practice on screening for the Triad in the adolescent population. To (1) evaluate the prevalence of Triad risk factors and iron supplementation in high school distance runners and (2) pilot a screening tool for Triad risk score. Descriptive epidemiology study. The study population included female high school athletes who participated in cross-country/track. Participants completed a survey including questions regarding dietary habits, menstrual history, and bone stress injury (BSI) history. They then underwent evaluation of 25-hydroxyvitamin D, free triiodothyronine (T3), and dual-energy x-ray absorptiometry scan to measure body fat and BMD through use of age-, sex-, and ethnicity-matched Z scores. Triad scores were calculated. Relationships were analyzed using Spearman correlation coefficient. There were 38 study participants (mean age, 16.9 years). Average body mass index was 19.8 kg/m2. Disordered eating or eating disorders were reported in 76.3% of runners; in addition, 23.7% reported delayed menarche, 45.9% had a history of amenorrhea or oligomenorrhea, 42.1% had low BMD (Z score < -1.0), and 15.8% reported prior BSI. Low free T3 was significantly associated with higher Triad risk scores (r S = -0.36; P = .028). More than 42% of athletes were supplementing iron. The prevalence of Triad risk factors in high school distance runners was high. Free T3 was inversely associated with Triad score, which may serve as an indicator of low energy availability. Nearly half of the athletes were using iron supplementation.

Hormonal Agents · Progesterone and Progestins

SUN-537 Progesterone Therapy and Serum Sclerostin Levels in Healthy Menopausal Women: A 3-month Randomized, Placebo Controlled Clinical Trial

Yang Y et al., 2019 Journal of the Endocrine Society Open Access

Sclerostin is an osteocyte-produced glycoprotein that inhibits the WNT/β-catenin pathway essential for bone formation. Sclerostin was postulated to relate to normal bone metabolism in 2001; we still have an incomplete understanding of its regulation. Estradiol, a bone antiresorptive ovarian steroid, inhibits sclerostin. Estrogen and progesterone act together in menstrual cycles and bone remodelling with progesterone exerting an anabolic effect. We hypothesized a relationship between progesterone and sclerostin because progesterone and estrogen are “partner” hormones in most tissues, and because progesterone and sclerostin modulate bone formation in opposite directions. Two observational menstrual cycle studies have reported sclerostin levels; neither documented changes across cycles nor in luteal phases during which progesterone levels are high(1)(,2). Some reports have also shown positive correlations between sclerostin and age and BMI. In this study, sclerostin was measured using an assay (MSD) of high sensitivity (LOD ± 1pg/mL), broad detection range (1-10 000 pg/mL), and intra/inter-assay precisions of 6% and 10% respectively(3). We collected fasting serum during a 3-month double blind randomized controlled trial (RCT) of 300 mg oral micronized progesterone vs placebo in symptomatic menopausal women; progesterone significantly decreased hot flushes/night sweats (vasomotor symptoms, VMS)(4). Statistical analysis showed sclerostin was not related to the 28-day baseline VMS Score (r=.18, p=.22). Pearson correlation coefficients were used to evaluate sclerostin vs baseline data and ANCOVA to analyze RCT results (alpha=0.05 significant, [SD]). The study’s purpose was to determine if sclerostin levels changed during a 3-month RCT of progesterone for VMS in healthy menopausal women(3). The primary outcome was sclerostin level in the 3(rd) month adjusted for baseline and randomization. Results showed the 52 participating women had a mean age of 55.2 (4.6) years, height 1.60 (0.07) m, weight 66.4 (8.6) kg, BMI 24.9 (2.9) kg/m(2) and were primarily Caucasian (91.2%). Baseline variables did not correlate with the baseline mean serum sclerostin level of 27.9 (10.2) pmol/L. Sclerostin had no statistically significant relationship with progesterone or placebo therapy during this RCT; mean changes were -1.07 and -2.60 pmol/L respectively. These data are the first evidence that progesterone neither increases nor decreases serum sclerostin levels. These data fit with the lack of menstrual cycle changes in sclerostin levels(1)(,2). That sclerostin did not correlate with age and BMI in this RCT is likely due to their low trial variance. A limitation of this study is the small sample size. However, it has considerable strength in its RCT design that can document causation. (1)Cidem M Gyn Obstetric Invest. 2012; (2)Liakou CG Endocrine 2016; (3)Van Lierop AH J Bone Miner Res 2011; (4)Hitchcock CL Menopause 2012.

Metabolic and Endocrine Agents · Corticosteroids

Systemic administration of low-dose naltrexone increases bone mass due to blockade of opioid growth factor receptor signaling in mice osteoblasts

Tanaka K et al., 2019 Life Sci

Opioid receptor blockers such as naloxone and naltrexone have been suggested to have a bone mass-increasing effect. However, the mechanisms at play have not been clarified. We examined the effects of naltrexone on osteoblasts and determined the expression of opioid growth factor receptor (OGFR) in osteoblasts. Naltrexone blocks the OGFR and other canonical opioid receptors. Thus, we designed experiments to clarify the effects of naltrexone on bone tissue by examining the physiological role of OGFR signaling in osteoblasts and the changes in bone structure after naltrexone systemic administration in mice. We used mouse osteoblast-like cell line MC3T3-E1 for in vitro experiments. We cultured MC3T3-E1 cells in the presence of the OGFR agonist met-enkephalin (met-enk). Then, we measured cell proliferation activity and analyzed the expression levels of cell proliferation-related genes. For our in vivo experiments, we administered naltrexone intraperitoneally to mice daily for 28 days and administered the animals in the control group equivalent volumes of saline. After sacrificing the mice, we performed micro-computed tomography and bone morphology analyses. Met-enk suppressed cell proliferation in MC3T3-E1 cells. Moreover, Low dose naltrexone administration significantly increased their femoral bone mass, bone formation ratio, and osteoblast number/bone surface values when comparing the values for the same variables in the control group. Our results suggest that naltrexone increases bone mass due to osteoblast number increments caused by the OGFR signaling block. Opioid receptor blockers have potential as therapeutic agents for osteoporosis as well as opioid antagonists.

Prescribing Safety · Off-Label Prescribing

Mortality risk reduction differs according to bisphosphonate class: a 15-year observational study

Bliuc D et al., 2019 Osteoporos Int

In this prospective cohort of 6120 participants aged 50+, nitrogen-bisphosphonates but not non-nitrogen bisphosphonates were associated with a significant 34% mortality risk reduction compared to non-treated propensity score matched controls. These findings open new avenues for research into mechanistic pathways. Emerging evidence suggests that bisphosphonates (BP), first-line treatment of osteoporosis, are associated with reduced risks for all-cause mortality. This study aimed to determine the association between different BP types and mortality risk in participants with or without a fracture. A prospective cohort study of users of different BPs matched to non-users by propensity score (age, gender, co-morbidities, fragility fracture status) and time to starting the BP medication from the population-based Canadian Multicentre Osteoporosis Study from nine Canadian centres followed from 1995 to 2013. Mortality risk for bisphosphonate users vs matched non-users was assessed using pairwise multivariable Cox proportional hazards models. There were 2048 women and 308 men on BP and 1970 women and 1794 men who did not receive medication for osteoporosis. The relationship between BP and mortality risk was explored in three separate 1:1 propensity score-matched cohorts of BP users and no treatment (etidronate, n = 599, alendronate, n = 498, and risedronate n = 213). Nitrogen BP (n-BP) (alendronate and risedronate) was associated with lower mortality risks [pairwise HR, 0.66 (95% CI, 0.48-0.91)] while the less potent non-n-BP, etidronate, was not [pairwise HR: 0.89 (95% CI, 0.66-1.20)]. A direct comparison between n-BP and etidronate (n = 340 pairs) also suggested a better survival for n-BP [paired HR, 0.47 (95%CI, (95% CI, 031-0.70)] for n-BP vs. etidronate]. Compared to no treatment, nitrogen but not non-nitrogen bisphosphonates appear to be associated with better survival.

Hormonal Agents · Progesterone and Progestins

Progesterone for the prevention and treatment of osteoporosis in women

Prior JC, 2018 Climacteric Open Access

Estradiol (E2) is women's dominant 'bone hormone' since it is essential for development of adolescent peak bone mineral density (BMD) and physiological levels prevent the rapid (3-week) bone resorption that causes most adult BMD loss. However, deceasing E2 levels trigger bone resorption/loss. Progesterone (P4) is E2's physiological partner, collaborating with E2 in every cell/tissue; its bone 'job' is to increase P4-receptor-mediated, slow (3-4 months) osteoblastic new bone formation. When menstrual cycles are normal length and normally ovulatory, E2 and P4 are balanced and BMD is stable. However, clinically normal cycles commonly have ovulatory disturbances (anovulation, short luteal phases) and low P4 levels; these are more frequent in teen and perimenopausal women and increased by everyday stressors: energy insufficiency, emotional/social/economic threats and illness. Meta-analysis shows that almost 1%/year spinal BMD loss occurs in those with greater than median (∼31%) of ovulatory disturbed cycles. Prevention of osteoporosis and fragility fractures requires the reversal of stressors, detection and treatment of teen-to-perimenopausal recurrent cycle/ovulatory disturbances with cyclic oral micronized progesterone. Low 'Peak Perimenopausal BMD' is likely the primary risk for fragility fractures in later life. Progesterone plus estradiol or other antiresorptive therapies adds 0.68%/year and may be a highly effective osteoporosis treatment. Randomized controlled trials are still needed to confirm progesterone's important role in women's bone formation.

Nutrition and Metabolic Health · Dietary Patterns

Dietary patterns in men and women are simultaneously determinants of altered glucose metabolism and bone metabolism

Langsetmo L et al., 2016 Nutr Res

We hypothesized that diet would have direct effects on glucose metabolism with direct and indirect effects on bone metabolism in a cohort of Canadian adults. We assessed dietary patterns (Prudent [fruit, vegetables, whole grains, fish, and legumes] and Western [soft drinks, potato chips, French fries, meats, and desserts]) from a semiquantitative food frequency questionnaire. We used fasting blood samples to measure glucose, insulin, homeostatic model assessment insulin resistance (HOMA-IR), 25-hydroxyvitamin D (25OHD), parathyroid hormone, bone-specific alkaline phosphatase (a bone formation marker), and serum C-terminal telopeptide (CTX; a bone resorption marker). We used multivariate regression models adjusted for confounders and including/excluding body mass index. In a secondary analysis, we examined relationships through structural equations models. The Prudent diet was associated with favorable effects on glucose metabolism (lower insulin and HOMA-IR) and bone metabolism (lower CTX in women; higher 25OHD and lower parathyroid hormone in men). The Western diet was associated with deleterious effects on glucose metabolism (higher glucose, insulin, and HOMA-IR) and bone metabolism (higher bone-specific alkaline phosphatase and lower 25OHD in women; higher CTX in men). Body mass index adjustment moved point estimates toward the null, indicating partial mediation. The structural equation model confirmed the hypothesized linkage with strong effects of Prudent and Western diet on metabolic risk, and both direct and indirect effects of a Prudent diet on bone turnover. In summary, a Prudent diet was associated with lower metabolic risk with both primary and mediated effects on bone turnover, suggesting that it is a potential target for reducing fracture risk.

Nutrition and Metabolic Health · Dietary Patterns

Calcium and vitamin D intake and mortality: results from the Canadian Multicentre Osteoporosis Study (CaMos)

Langsetmo L et al., 2013 J Clin Endocrinol Metab Open Access

Calcium and vitamin D are recommended for bone health, but there are concerns about adverse risks. Some clinical studies suggest that calcium intake may be cardioprotective, whereas others report increased risk associated with calcium supplements. Both low and high serum levels of 25-hydroxyvitamin D have been associated with increased mortality. The purpose of this study was to determine the association between total calcium and vitamin D intake and mortality and heterogeneity by source of intake. The Canadian Multicentre Osteoporosis Study cohort is a population-based longitudinal cohort with a 10-year follow-up (1995-2007). This study included randomly selected community-dwelling men and women. A total of 9033 participants with nonmissing calcium and vitamin D intake data and follow-up were studied. Exposure: Total calcium intake (dairy, nondairy food, and supplements) and total vitamin D intake (milk, yogurt, and supplements) were recorded. Outcome: The outcome variable was all-cause mortality. There were 1160 deaths during the 10-year period. For women only, we found a possible benefit of higher total calcium intake, with a hazard ratio of 0.95 (95% confidence interval, 0.89-1.01) per 500-mg increase in daily calcium intake and no evidence of heterogeneity by source; use of calcium supplements was also associated with reduced mortality, with hazard ratio of 0.78 (95% confidence interval, 0.66-0.92) for users vs nonusers with statistically significant reductions remaining among those with doses up to 1000 mg/d. These associations were not modified by levels of concurrent vitamin D intake. No definitive associations were found among men. Calcium supplements, up to 1000 mg/d, and increased dietary intake of calcium may be associated with reduced risk of mortality in women. We found no evidence of mortality benefit or harm associated with vitamin D intake.

Ovarian Hormones · Estrogen

The female athlete triad

Nazem TG et al., 2012 Sports health

The female athlete triad (the triad) is an interrelationship of menstrual dysfunction, low energy availability (with or without an eating disorder), and decreased bone mineral density; it is relatively common among young women participating in sports. Diagnosis and treatment of this potentially serious condition is complicated and often requires an interdisciplinary team. Articles from 1981 to present found on PubMed were selected for review of major components of the female athlete triad as well as strategies for diagnosis and treatment of the conditions. The main goal in treatment of young female athletes with the triad is a natural return of menses as well as enhancement of bone mineral density. While no specific drug intervention has been shown to consistently improve bone mineral density in this patient population, maximizing energy availability and optimizing vitamin D and calcium intake are recommended. Treatment requires a multidisciplinary approach involving health care professionals as well as coaches and family members. Prevention of this condition is important to minimize complications of the female athlete triad.

Diagnostic Criteria and Classification · Terminology and Definitions

Osteoporosis-related fracture case definitions for population-based administrative data

Lix LM et al., 2012 BMC Public Health Open Access

Population-based administrative data have been used to study osteoporosis-related fracture risk factors and outcomes, but there has been limited research about the validity of these data for ascertaining fracture cases. The objectives of this study were to: (a) compare fracture incidence estimates from administrative data with estimates from population-based clinically-validated data, and (b) test for differences in incidence estimates from multiple administrative data case definitions. Thirty-five case definitions for incident fractures of the hip, wrist, humerus, and clinical vertebrae were constructed using diagnosis codes in hospital data and diagnosis and service codes in physician billing data from Manitoba, Canada. Clinically-validated fractures were identified from the Canadian Multicentre Osteoporosis Study (CaMos). Generalized linear models were used to test for differences in incidence estimates. For hip fracture, sex-specific differences were observed in the magnitude of underand over-ascertainment of administrative data case definitions when compared with CaMos data. The length of the fracture-free period to ascertain incident cases had a variable effect on over-ascertainment across fracture sites, as did the use of imaging, fixation, or repair service codes. Case definitions based on hospital data resulted in under-ascertainment of incident clinical vertebral fractures. There were no significant differences in trend estimates for wrist, humerus, and clinical vertebral case definitions. The validity of administrative data for estimating fracture incidence depends on the site and features of the case definition.

Nutrition and Metabolic Health · Dietary Patterns

Implications of vitamin D deficiency in pregnancy and lactation

Mulligan ML et al., 2010 American journal of obstetrics and gynecology

Vitamin D is an essential fat soluble vitamin and a key modulator of calcium metabolism in children and adults. Because calcium demands increase in the third trimester of pregnancy, vitamin D status becomes crucial for maternal health, fetal skeletal growth, and optimal maternal and fetal outcomes. Vitamin D deficiency is common in pregnant women (5-50%) and in breastfed infants (10-56%), despite the widespread use of prenatal vitamins, because these are inadequate to maintain normal vitamin D levels (>or=32 ng/mL). Adverse health outcomes such as preeclampsia, low birthweight, neonatal hypocalcemia, poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases have been linked to low vitamin D levels during pregnancy and infancy. Studies are underway to establish the recommended daily doses of vitamin D in pregnant women. This review discusses vitamin D metabolism and the implications of vitamin D deficiency in pregnancy and lactation.

Nutrition and Metabolic Health · Dietary Patterns

Dietary patterns in Canadian men and women ages 25 and older: relationship to demographics, body mass index, and bone mineral density

Langsetmo L et al., 2010 BMC Musculoskelet Disord Open Access

Previous research has shown that underlying dietary patterns are related to the risk of many different adverse health outcomes, but the relationship of these underlying patterns to skeletal fragility is not well understood. The objective of the study was to determine whether dietary patterns in men (ages 25-49, 50+) and women (pre-menopause, post-menopause) are related to femoral neck bone mineral density (BMD) independently of other lifestyle variables, and whether this relationship is mediated by body mass index. We performed an analysis of 1928 men and 4611 women participants in the Canadian Multicentre Osteoporosis Study, a randomly selected population-based longitudinal cohort. We determined dietary patterns based on the self-administered food frequency questionnaires in year 2 of the study (1997-99). Our primary outcome was BMD as measured by dual x-ray absorptiometry in year 5 of the study (2000-02). We identified two underlying dietary patterns using factor analysis and then derived factor scores. The first factor (nutrient dense) was most strongly associated with intake of fruits, vegetables, and whole grains. The second factor (energy dense) was most strongly associated with intake of soft drinks, potato chips and French fries, certain meats (hamburger, hot dog, lunch meat, bacon, and sausage), and certain desserts (doughnuts, chocolate, ice cream). The energy dense factor was associated with higher body mass index independent of other demographic and lifestyle factors, and body mass index was a strong independent predictor of BMD. Surprisingly, we did not find a similar positive association between diet and BMD. In fact, when adjusted for body mass index, each standard deviation increase in the energy dense score was associated with a BMD decrease of 0.009 (95% CI: 0.002, 0.016) g/cm(2) for men 50+ years old and 0.004 (95% CI: 0.000, 0.008) g/cm(2) for postmenopausal women. In contrast, for men 25-49 years old, each standard deviation increase in the nutrient dense score, adjusted for body mass index, was associated with a BMD increase of 0.012 (95% CI: 0.002, 0.022) g/cm(2). In summary, we found no consistent relationship between diet and BMD despite finding a positive association between a diet high in energy dense foods and higher body mass index and a strong correlation between body mass index and BMD. Our data suggest that some factor related to the energy dense dietary pattern may partially offset the advantages of higher body mass index with regard to bone health.

Cycle Disorders · Amenorrhea

The menstrual cycle: a biological marker of general health in adolescents

Popat VB et al., 2008 Ann N Y Acad Sci Open Access

Menstruation is the cyclic, orderly sloughing of the uterine lining on account of the interactions of hormones produced by the hypothalamus, pituitary, and ovaries. There is a tendency among parents and clinicians to view oligo-amenorrhea as a normal variant in the teen years. In fact, the 95th percentile for the time interval between cycles is 90 days. Thus, it is abnormal for an adolescent to be amenorrheic for greater than 3 months, even in the early gynecologic years. Identification of abnormal menstrual patterns throughout adolescence may permit early identification of potential health concerns for adulthood. Few problems in gynecologic endocrinology are as complex or challenging to the clinician as amenorrhea. However, thorough evaluation of menstrual cycle disorders in adolescence provides a window of opportunity for early diagnosis and treatment of conditions affecting the hypothalamic-pituitary-ovarian (HPO) axis. Here we discuss a systematic approach to the evaluation and treatment of amenorrhea in adolescents who do not have androgen excess. There is strong evidence that estrogen deficiency is a risk factor for later development of osteoporosis and hip fracture. Delay in the evaluation and treatment of disordered menses in some cases may contribute to reduced bone density. Both patients and clinicians need to view the ovary as an important endocrine organ that helps maintain health, especially bone health.

Guidelines by Issuing Body · Specialty and Consensus Panels

Dual-Energy X-Ray Absorptiometry Technical issues: the 2007 ISCD Official Positions

Simonelli C et al., 2008 J Clin Densitom

At the 2007 Position Development Conference, the Dual-Energy X-ray Absorptiometry Technical Task Force investigated three major areas of bone density testing. Although bone mineral density (BMD) testing in men had previously been reviewed at the 2005 Position Development Conference, we reviewed the most recent data in men to develop appropriate indications for bone density testing in men. We continue to recommend screening at age 70 and discuss the clinical risk factors that may be an appropriate indication for earlier BMD testing. Menopausal transition (perimenopause) was considered an important time to consider BMD evaluation because bone loss may be significant prior to menopause. However, because fracture risk is inherently low in women of this age without other risk factors, screening BMD testing is not appropriate. We discuss the risk factors that are strong indicators of fracture risk that may be increased during the menopause transition. The presence of these risk factors are appropriate indications for BMD testing with applicability of WHO diagnostic categorization. The issue of establishing a high threshold for BMD was investigated thoroughly and the current literature was reviewed. Despite the fact there is agreement that all BMD values greater than T-score -1.0 are not normal, it was felt that because of the paucity of sensitivity data and confounding factors such as high body mass index, an upper threshold could not be established or recommended at this time. This was felt to be an important area for further research.

Nutrition and Metabolic Health · Dietary Patterns

Vitamin D deficiency in a healthy group of mothers and newborn infants

Lee JM et al., 2007 Clinical pediatrics

Plasma 25-hydroxyvitamin D was measured in 40 healthy, mostly Black, mother-infant pairs. Although a majority of mothers received a daily prenatal multivitamin, vitamin D deficiency (<30 nmol/L), was found in 50% of mothers and 65% of their newborn infants, with a positive correlation between maternal and infant plasma 25-hydroxyvitamin D concentrations. Maternal vitamin D deficiency may represent an important risk factor for the development of rickets in children.

Guidelines by Clinical Area · Bone and Endocrine Guidelines

2002 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada

Brown JP et al., 2002 CMAJ

To revise and expand the 1996 Osteoporosis Society of Canada clinical practice guidelines for the management of osteoporosis, incorporating recent advances in diagnosis, prevention and management of osteoporosis, and to identify and assess the evidence supporting the recommendations. Options: All aspects of osteoporosis care and its fracture complications - including classification, diagnosis, management and methods for screening, as well as prevention and reducing fracture risk - were reviewed, revised as required and expressed as a set of recommendations. Outcomes: Strategies for identifying and evaluating those at high risk; the use of bone mineral density and biochemical markers in diagnosis and assessing response to management; recommendations regarding nutrition and physical activity; and the selection of pharmacologic therapy for the prevention and management of osteoporosis in men and women and for osteoporosis resulting from glucocorticoid treatment. Evidence: All recommendations were developed using a justifiable and reproducible process involving an explicit method for the evaluation and citation of supporting evidence. Values: All recommendations were reviewed by members of the Scientific Advisory Council of the Osteoporosis Society of Canada, an expert steering committee and others, including family physicians, dietitians, therapists and representatives of various medical specialties involved in osteoporosis care (geriatric medicine, rheumatology, endocrinology, obstetrics and gynecology, nephrology, radiology) as well as methodologists from across Canada. BENEFITS, Harm and Costs: Earlier diagnosis and prevention of fractures should decrease the medical, social and economic burdens of this disease. Recommendations: This document outlines detailed recommendations pertaining to all aspects of osteoporosis. Strategies for identifying those at increased risk (i.e., those with at least one major or 2 minor risk factors) and screening with central dual-energy x-ray absorptiometry at age 65 years are recommended. Bisphosphonates and raloxifene are first-line therapies in the prevention and treatment of postmenopausal osteoporosis. Estrogen and progestin/progesterone is a first-line therapy in the prevention and a second-line therapy in the treatment of postmenopausal osteoporosis. Nasal calcitonin is a second-line therapy in the treatment of postmenopausal osteoporosis. Although not yet approved for use in Canada, hPTH(1-34) is expected to be a first-line treatment for postmenopausal women with severe osteoporosis. Ipriflavone, vitamin K and fluoride are not recommended. Bisphosphonates are the first-line therapy for the prevention and treatment of osteoporosis in patients requiring prolonged glucocorticoid therapy and for men with osteoporosis. Nasal or parenteral calcitonin is a first-line treatment for pain associated with acute vertebral fractures. Impact-type exercise and age-appropriate calcium and vitamin D intake are recommended for the prevention of osteoporosis. Validation: All recommendations were graded according to the strength of the evidence; where the evidence was insufficient and recommendations were based on consensus opinion alone, this is indicated. These guidelines are viewed as a work in progress and will be updated periodically in response to advances in this field.

Hormonal Agents · Estrogen Preparations

Management of the extremely preterm infant: is the replacement of estradiol and progesterone beneficial?

Trotter A et al., 2001 Paediatr Drugs

This review presents data to suggest that postnatal estradiol and progesterone replacement therapy may be beneficial in preterm infants. During pregnancy, maternal plasma levels of estradiol and progesterone increase up to 100-fold compared to the nonpregnant status. The fetus is also exposed to these increasing hormone levels. After delivery, estradiol and progesterone levels drop by a factor of 100 within 1 day. Whereas this is a physiological condition for an infant born at term, preterm delivery means withdrawal from the placental supply of these hormones at an earlier developmental stage. Seventy years ago, the idea was raised that preterm infants may benefit from the replacement of estrogens. Studies in which estrogen was injected subcutaneously showed only a slightly better bodyweight gain compared to placebo-treated controls and therefore routine use was not established. The effective treatment of postmenopausal osteoporosis with hormone replacement therapy led to a pilot study of estradiol and progesterone therapy to prevent osteopenia of prematurity. The highest median bone mineral accretion rate was found in the replacement group when the supplementation with calcium and phosphorus was also sufficient. None of the previous studies dealing with estrogen replacement controlled for achieved plasma levels of estradiol in the infants. In our controlled randomised pilot study with 30 preterm infants (15 in each group), we aimed to maintain intra-uterine plasma levels of estradiol and progesterone. Preterm infants with replacement of estradiol and progesterone for 6 weeks postnatally showed trends to higher bone mineral accumulation. In addition, a trend towards a lower incidence of chronic lung disease was found. Neurodevelopmental follow-up showed normal psychomotor development in infants given estradiol and progesterone, whereas the untreated infants (controls) showed a trend towards delayed development. Recent research emphasises that estradiol and progesterone may be important for brain development. Thus, while there is data indicating that postnatal estradiol and progesterone replacement therapy may be beneficial in preterm infants, experience with this new therapy is limited and extensive research is needed to address the potential benefits and to rule out adverse effects.

Nutrition and Metabolic Health · Eating Disorders and Underfueling

Dietary restraint, exercise, and bone density in young women: are they related?

McLean JA et al., 2001 Med Sci Sports Exerc

Women with high scores for dietary restraint have been found to have higher 24-h urinary cortisol excretion and a higher prevalence of subclinical ovulatory disturbances, both of which may be risk factors for bone loss. The purpose of this study was to explore relationships between dietary restraint and bone health in regularly menstruating young women. 62 women (age: 21.7 +/- 2.5 yr) had body composition and total body and lumbar spine bone mineral density (BMD) and content (BMC) assessed using dual-energy x-ray absorptiometry. Dietary restraint was assessed using the restraint subscale from the Three-Factor Eating Questionnaire: 29 women had low restraint (LR; restraint score 0--5), 33 had high restraint (HR; restraint score 13--21). Exercise (h x wk(-1)) was assessed by questionnaire on two occasions. LR and HR women were similar in age and body composition (fat mass = 15.0 +/- 4.7 kg, lean mass = 40.9 +/- 4.9 kg), but HR women exercised more (3.4 +/- 1.7 vs 2.2 +/- 1.8 h x wk(-1), P < 0.05). Exercise was correlated with BMD and BMC, and when it was included as a covariate, total body BMC was significantly lower in HR than LR women. In multiple regression analysis, weekly hours of exercise and restraint score were significant predictors of total body BMD and BMC. The observations of this cross-sectional study suggest that high levels of cognitive dietary restraint, or associated factors such as higher cortisol, may attenuate the positive effects of exercise on bone in young women.

Hormone Therapy · Benefits and Risks

Transdermal progesterone cream for vasomotor symptoms and postmenopausal bone loss

Leonetti HB et al., 1999 Obstet Gynecol

To determine effectiveness of transdermal progesterone cream for controlling vasomotor symptoms and preventing postmenopausal bone loss. We randomly assigned 102 healthy women within 5 years of menopause to transdermal progesterone cream or placebo. Study subjects and investigators were masked until data analysis was completed. An initial evaluation included complete history, physical examination, bone mineral density determination, and serum studies (TSH, FSH, lipid profile, and chemistry profile). Subjects were instructed to apply a quarter teaspoon of cream (containing 20 mg progesterone or placebo) to the skin daily. Each woman received daily multivitamins and 1200 mg of calcium and were seen every 4 months for review of symptoms. Bone scans and serum chemistries were repeated after 1 year. Thirty of the 43 (69%) in the treatment group and 26 of the 47 (55%) in the placebo group complained initially of vasomotor symptoms. Improvement or resolution of vasomotor symptoms, as determined by review of weekly symptom diaries, was noted in 25 of 30 (83%) treatment subjects and five of 26 (19%) placebo subjects (P < .001). However, the number of women who showed gain in bone mineral density exceeding 1.2% did not differ (alpha = .05, power of 80%). Although we found no protective effect on bone density after 1 year, we did see a significant improvement in vasomotor symptoms in the treated group.

Study Design · Randomized Controlled Trials

Design of the Women's Health Initiative clinical trial and observational study. The Women's Health Initiative Study Group

Women's Health Initiative Study Group, 1998 Control Clin Trials

The Women's Health Initiative (WHI) is a large and complex clinical investigation of strategies for the prevention and control of some of the most common causes of morbidity and mortality among postmenopausal women, including cancer, cardiovascular disease, and osteoporotic fractures. The WHI was initiated in 1992, with a planned completion date of 2007. Postmenopausal women ranging in age from 50 to 79 are enrolled at one of 40 WHI clinical centers nationwide into either a clinical trial (CT) that will include about 64,500 women or an observational study (OS) that will include about 100,000 women. The CT is designed to allow randomized controlled evaluation of three distinct a low-fat eating pattern, hypothesized to prevent breast cancer and colorectal cancer and, secondarily, coronary heart disease; hormone replacement therapy, hypothesized to reduce the risk of coronary heart disease and other cardiovascular diseases and, secondarily, to reduce the risk of hip and other fractures, with increased breast cancer risk as a possible adverse outcome; and calcium and vitamin D supplementation, hypothesized to prevent hip fractures and, secondarily, other fractures and colorectal cancer. Overall benefit-versus-risk assessment is a central focus in each of the three CT components. Women are screened for participation in one or both of the components--dietary modification (DM) or hormone replacement therapy (HRT)--of the CT, which will randomize 48,000 and 27,500 women, respectively. Women who prove to be ineligible for, or who are unwilling to enroll in, these CT components are invited to enroll in the OS. At their 1-year anniversary of randomization, CT women are invited to be further randomized into the calcium and vitamin D (CaD) trial component, which is projected to include 45,000 women. The average follow-up for women in either CT or OS is approximately 9 years. Concerted efforts are made to enroll women of racial and ethnic minority groups, with a target of 20% of overall enrollment in both the CT and OS. This article gives a brief description of the rationale for the interventions being studied in each of the CT components and for the inclusion of the OS component. Some detail is provided on specific study design choices, including eligibility criteria, recruitment strategy, and sample size, with attention to the partial factorial design of the CT. Some aspects of the CT monitoring approach are also outlined. The scientific and logistic complexity of the WHI implies particular leadership and management challenges. The WHI organization and committee structure employed to respond to these challenges is also briefly described.

Guidelines by Clinical Area · Bone and Endocrine Guidelines

Prevention and management of osteoporosis: consensus statements from the Scientific Advisory Board of the Osteoporosis Society of Canada. 5. Physical activity as therapy for osteoporosis

Prior JC et al., 1996 CMAJ

To examine exercise as a therapy for people with osteoporosis. Options: Immobilization, standing low-load and high-load physical activities. Outcomes: Risk of injury, quality of life, risk of falls and fractures, strength and posture and pain management. Evidence: Relevant epidemiologic studies, clinical trials and reviews were examined, including the large-scale FICSIT trial in the United States, a prospective 4-year study of women enrolled in an exercise program in Toronto and the large-scale Study of Osteoporotic Fractures. Values: Minimizing risk of injury and increasing quality of life were given a high value. BENEFITS, HARMS, And Costs: Moderate physical activity in people with osteoporosis can reduce the risk of falls and fractures, decrease pain and improve fitness and overall quality of life. It may also stimulate bone gain and decrease bone loss. Its positive effects are an adjunct to other interventions, such as hormonal therapy. It may give patients the confidence to resume regular activity and can provide social interaction and support. During exercise programs, proper nutrition is necessary to prevent excessive weight loss and impaired immune function resulting from inadequate protein, vitamin and mineral intake. Recommendations: Immobilization should be avoided if possible in anyone with osteoporosis or at increased risk for osteoporosis. Regular, moderate physical activity is recommended for those with osteoporosis. Elderly people should be assessed for risk of falling to identify those in greatest need of an exercise program. Community group exercise programs are beneficial. Younger people with osteoporosis also need exercise that will preserve or improve bone mass, muscular strength, endurance and cardiovascular fitness. Weight loss as a result of physical activity should be avoided and adequate intake of protein, vitamins and minerals assured. Because the benefits of physical activity are independent of the effect of other therapies, physical activity is an essential adjunct to appropriate nutrition and other therapies. Validation: These recommendations were developed by the Scientific Advisory Board of the Osteoporosis Society of Canada at its 1995 Consensus Conference. They are in agreement with the position taken on osteoporosis and exercise by the United States Center for Disease Control and Prevention and the American College of Sports Medicine. Sponsors: Sponsors of the 1995 conference included the Dairy Farmers of Canada, Eli Lilly Canada, Inc., Hoffmann-La Roche Canada Ltd., Merck Frosst Canada Inc. and Procter & Gamble Pharmaceuticals Canada Inc.

Nutrition and Metabolic Health · Dietary Patterns

Effect of dietary boron on mineral, estrogen, and testosterone metabolism in postmenopausal women

Nielsen FH et al., 1987 FASEB journal : official publication of the Federation of American Societies for Experimental Biology

A study was done to examine the effects of aluminum, magnesium, and boron on major mineral metabolism in postmenopausal women. This communication describes some of the effects of dietary boron on 12 women between the ages of 48 and 82 housed in a metabolic unit. A boron supplement of 3 mg/day markedly affected several indices of mineral metabolism of seven women consuming a low-magnesium diet and five women consuming a diet adequate in magnesium; the women had consumed a conventional diet supplying about 0.25 mg boron/day for 119 days. Boron supplementation markedly reduced the urinary excretion of calcium and magnesium; the depression seemed more marked when dietary magnesium was low. Boron supplementation depressed the urinary excretion of phosphorus by the low-magnesium, but not by the adequate-magnesium, women. Boron supplementation markedly elevated the serum concentrations of 17 beta-estradiol and testosterone; the elevation seemed more marked when dietary magnesium was low. Neither high dietary aluminum (1000 mg/day) nor an interaction between boron and aluminum affected the variables presented. The findings suggest that supplementation of a low-boron diet with an amount of boron commonly found in diets high in fruits and vegetables induces changes in postmenopausal women consistent with the prevention of calcium loss and bone demineralization.

Metabolic and Endocrine Agents · Corticosteroids

Hemodialysis patients with a unique mineralizing defect unresponsive to 1,25-dihydroxycholecalciferol. Dialysis osteomalacic syndrome

Cameron EC et al., 1980 Contrib Nephrol

5 patients are described who developed severe osteomalacia with spontaneous fractures after 2-4 years on dialysis. Phosphate control, vitamin D2 therapy and parathyroidectomy were ineffective. These individuals showed a hypercalcemic tendency but little histologic or radiographic evidence of osteitis fibrosa. After parathyroidectomy, the hypercalcemic tendency remained and bone biopsy revealed gross osteomalacia. A 6to 12-month therapeutic trial with 1,25-dihydroxycholecalciferol (1,25[OH]2D3) in 3 did not arrest skeletal deterioration. 4 subsequently developed dialysis encephalopathy. These patients appear to have a unique mineralizing defect unresponsive to 1,25(OH)2D3. This "dialysis osteomalacic syndrome" may result from toxic substances associated with uremia or the hemodialysis regimen.

Metabolic and Endocrine Agents · Corticosteroids

Experience with 1,25-dihydroxycholecalciferol therapy in undergoing hemodialysis patients with progressive vitamin D2-treated osteodystrophy

Prior JC et al., 1979 Am J Med

Six long-term hemodialysis patients with progressive skeletal deterioration during long-term pharmacologic vitamin D2 therapy were treated for six to 12 months with oral 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) to determine its therapeutic effectiveness in vitamin D2-unresponsive osteodystrophy. On bone biopsy, three of the patients had severe osteomalacia and three showed predominant osteitis fibrosa. Previous therapies, including phosphate binders and dialysis schedules, were maintained. The three patients with osteomalacia and the two with osteitis fibrosa showed clinical deterioration. There was no significant change in serum calcium, phosphate, alkaline phosphatase, bone densitometry, immunoreactive parathyroid hormone levels or bone histology. Roentgenograms showed multiple new fractures of ribs and femoral necks in the patients with osteomalacia and increased bone resorption in two of three patients with osteitis fibrosa. 1,25-(OH)2D3 dosage had to be decreased in all patients because of hypercalcemia with a mean tolerated dose of 0.22 microgram/day. In these patients, 1,25-(OH)2D3 was not effective therapy for progressive osteodystrophy unresponsive to pharmacologic vitamin D2.