Beyond BMI: Visceral Fat and Comorbidities as Major Risk Factors for Urinary Incontinence in Elderly Women-A Case-Control Study.

BACKGROUND AND AIMS: Urinary incontinence (UI) is prevalent in older women, reducing quality of life and increasing healthcare burden. The purpose of this study was to investigate the association between UI and comprehensive body composition-viz, visceral fat, waist circumference, and muscle mass-in older Iranian women.

METHODS

This case-control study included 845 community-dwelling women aged ≥ 60 years from the Amirkola Health Assessment Project (AHAP-Phase 2). Participants were assigned to UI (n = 444) and non-UI (n = 401) groups using the 3 Incontinence Questionnaire (3IQ). Data collection included demographic and clinical interviews, anthropometric measurements (BMI, waist, and hip circumference), and dual-energy X-ray absorptiometry (DXA), for body composition analysis (visceral adipose tissue, total fat mass, lean mass, and android/gynoid fat ratio). Multivariate logistic regression determined independent predictors of UI.

RESULTS

The prevalence of UI was 52.5% (444/845). Women with UI were considerably older, had more chronic diseases, and more often used sedative-hypnotic drugs. UI cases had higher rates of obesity, larger waist circumference (mean difference: 1.82 cm, 95% CI: 0.33-3.31), higher visceral fat (mean difference: 57.2 g, 95% CI: 11.6-102.8), and higher android/gynoid fat ratio (mean difference: 0.02, 95% CI: 0.002-0.038). Lean mass was not significantly different. No significant differences in body composition were found between UI subtypes. Multivariate logistic regression revealed that normal-weight women (BMI < 25) had 48% lower odds of UI compared to obese women (OR = 0.52, 95% CI: 0.33-0.82, p = 0.005). Each additional chronic disease increased UI risk by 40%.

CONCLUSION

Central obesity and the burden of chronic diseases are strongly associated with UI in older women, while normal BMI has protective effects. It should be noted that a normal BMI does not fully account for UI risk factors. Interventions targeting the reduction of visceral fat and comorbidity control may improve urinary health.