Use of contraceptives and risk of inflammatory bowel disease: a nested case-control study

Thomas Joshua Pasvol; Stuart Bloom; Anthony Walter Segal; Greta Rait; Laura Horsfall

doi:10.1111/apt.16647

Autoimmune and Inflammatory Disease Gut and Inflammatory Bowel Disease

Use of contraceptives and risk of inflammatory bowel disease: a nested case-control study

Pasvol TJ, Bloom S, Segal AW, Rait G, Horsfall L

Published February 2022 Alimentary pharmacology & therapeutics, 55(3), 318-326

DOI 10.1111/apt.16647 PMID 34662440 PMC PMC7612921

RRM Academy Synopsis

Combined birth control pills linked to higher Crohn's disease risk

In a UK study of women aged 15 to 49, combined oral contraceptive pill use was linked to higher Crohn's disease risk. Longer combined pill use was linked to higher risk of both Crohn's disease and ulcerative colitis, with a smaller increase for ulcerative colitis. The nested case-control design compared women with new inflammatory bowel disease to matched controls.

Key Findings

The study matched 2231 women with new Crohn's disease to 13 279 controls, and 2701 women with new ulcerative colitis to 16 061 controls.
Combined oral contraceptive pill use was associated with Crohn's disease (OR 1.60, 95% CI 1.41-1.82). Current users of second-generation pills had an OR of 2.12 (95% CI 1.83-2.44).
Each additional month of combined pill exposure per year of follow-up raised Crohn's disease risk by 6.4% (95% CI 5.1-7.7) and ulcerative colitis risk by 3.3% (95% CI 2.1-4.4).
Progestogen-only pills showed no association with Crohn's disease (OR 1.09, 95% CI 0.84-1.40). Among current users of those pills, ulcerative colitis odds were higher (OR 1.35, 95% CI 1.12-1.64).
Parenteral progestogen-only methods (intrauterine systems, implants and injections) were not associated with Crohn's disease (OR 1.15, 95% CI 0.99-1.47) or ulcerative colitis (OR 1.17, 95% CI 0.98-1.39).

Interpretation

The study took exposure from prescriptions recorded in UK general practices, so the results are associations between prescriptions and a later diagnosis. The authors say the pattern broadly fits the idea that estrogen in oral contraceptives is linked to inflammatory bowel disease. They note that contraceptives from sexual health clinics were missing from the records.

RRM Context

Restorative reproductive medicine seeks the cause of cycle symptoms and works with the cycle. Combined pills are suppressive medications that stop ovulation. This study adds inflammatory bowel disease to the outcomes linked with longer combined pill use.

Our editorial summary of this paper, not the article's abstract.

Abstract

Background

How contraceptive formulation, dose, duration of therapy and mode of delivery affects the risk of inflammatory bowel disease (IBD) is poorly described.

Aim

To examine associations between types of hormonal contraception and development of IBD.

Methods

This was a nested case-control study using IQVIA Medical Research Data. Women aged 15-49 years with a new diagnosis of IBD were matched with up to six controls by age, practice and year. Odds ratios (OR) and 95% confidence intervals (95% CI) for incident IBD and use of contraception were calculated.

Results

4932 incident cases of IBD were matched to 29 340 controls. Use of combined oral contraceptive pills (COCPs) was associated with the development of Crohn's disease and ulcerative colitis (OR 1.60 [1.41-1.82] and 1.30 [1.15-1.45], respectively). Each additional month of COCP exposure per year of follow-up increased risk of Crohn's disease by 6.4% (5.1%-7.7%) and ulcerative colitis by 3.3% (2.1%-4.4%). Progestogen-only pills had no effect on Crohn's disease risk (OR 1.09 [0.84-1.40]) but there was a modest association with ulcerative colitis (OR 1.35 [1.12-1.64]). Parenteral contraception was not associated with the development of Crohn's disease or ulcerative colitis (OR 1.15 [0.99-1.47] and 1.17 [0.98-1.39], respectively).

Conclusions

We observed an increase in the risk of IBD with increasing duration of exposure to COCPs. Progestogen-only pills were not associated with Crohn's disease but there was a modest association with ulcerative colitis. There was no association between parenteral progestogen-only contraception and IBD. These findings are broadly consistent with a hypothesis that the oestrogen component of contraception may drive IBD pathogenesis.

Topics

Autoimmune and Inflammatory Disease › Gut and Inflammatory Bowel Disease › Inflammatory Bowel Disease · Contraception › Oral Contraceptives › Autoimmune Disease Risk

Thomas Joshua Pasvol, Stuart Bloom, Anthony Walter Segal, Greta Rait, Laura Horsfall

Tom Pasvol, T Pasvol, S Bloom, Tony Segal, A Segal, G Rait, L Horsfall

PMID 34662440 34662440 DOI 10.1111/apt.16647 10.1111/apt.16647 Pasvol et al. 2022, Pasvol 2022

Use of contraceptives and risk of inflammatory bowel disease: a nested case-control study

Combined birth control pills linked to higher Crohn's disease risk

Key Findings

Interpretation

RRM Context

Abstract

Topics

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