Effect of body mass index on the risk of anal incontinence and defecatory dysfunction in women

OBJECTIVE: The primary objective was to estimate the effect of body mass index on the risk of anal incontinence and defecatory dysfunction in a tertiary referral urogynecologic population. STUDY DESIGN: This was a cross-sectional study, including 519 new patients. Exposure was defined as body mass index. The primary outcome was any reported anal incontinence. The secondary outcome was any defecatory dysfunction. We used multiple logistic regression to estimate odds ratios and 95% confidence intervals for the effect of body mass index on anal incontinence and defecatory dysfunction. RESULTS: After adjusting for confounders, every 5 unit increase in body mass index was associated with a significantly increased odds of anal incontinence (odds ratio 1.25 95% confidence interval, 1.09 to 1.44) and a trend toward an increased odds of defecatory dysfunction (odds ratio 1.1 3 95% confidence interval, 0.98 to 1.31), although this was not statistically significant. CONCLUSION: Increasing body mass index is significantly associated with anal incontinence, but not defecatory dysfunction in women.