Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study
Alexandra Papaioannou, Jonathan D Adachi, Claudie Berger
Yawen Jiang, Richard Barron, R. Wirth, Tassos Anastassiades, G Ioannidis, Stephanie M Kaiser, Christopher S Kovacs, William D Leslie, Jerilynn C Prior, Tanveer Towheed, David Goltzman, David A Hanley, K Shawn Davison, S M Kaiser, S N Morin, James S. McGinley
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.
Introduction
This study aimed to examine direct and indirect effects of several factors on imminent (1 year) fracture risk.
Methods
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).
Results
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).
Conclusions
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.
imminent fracture risk elderly women structural equation model, Prior JC bone mineral density fracture risk CaMos, one year fracture risk prediction BMD T-score, Canadian Multicentre Osteoporosis Study imminent fracture, prior fracture falls physical functioning fracture prediction, SF-36 physical functioning general health fracture risk, bone mineral density latent variable fracture model, direct indirect pathways fracture risk elderly women, Papaioannou Adachi fracture risk scoring methods, population-based cohort imminent fracture prediction women over 65
PMID 32034452 32034452 DOI 10.1007/s00198-020-05330-2 10.1007/s00198-020-05330-2
Cite this article
A Papaioannou, J D Adachi, C Berger, Y Jiang, R Barron, J S McGinley, R J Wirth, T P Anastassiades, K S Davison, D A Hanley, G Ioannidis, S M Kaiser, C S Kovacs, W D Leslie, S N Morin, J C Prior, T Towheed, & D Goltzman (2020). Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA, 31(6), 1145-1153. https://doi.org/10.1007/s00198-020-05330-2
A Papaioannou, J D Adachi, C Berger, Y Jiang, R Barron, J S McGinley, et al. Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study. Osteoporos Int. 2020;31(6):1145-1153. doi:10.1007/s00198-020-05330-2
A Papaioannou, et al. "Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study." Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA, vol. 31, no. 6, 2020, pp. 1145-1153.
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