Association between obesity and urinary incontinence in older adults from multiple nationwide longitudinal cohorts.

Background: Obesity and urinary incontinence (UI) among older adults, particularly older men, are yet to be fully explored. Utilizing multiple nationwide prospective longitudinal cohorts representative of the US, UK, and European samples, we examined the association of body mass index (BMI) and waist circumference (WC) with UI among both older women and men.

Methods: We derived the data from multiple longitudinal cohorts that surveyed UI. Participants were asked if they had experienced urine leakage within the past 12 months or within the past six months. The measure of obesity was based on BMI and WC. We employed a random-effect logistic model to associate BMI and WC with UI, adjusting for covariates including age, race, education, residence area, marital status, number of children, smoking, drinking, hypertension, diabetes, cancer, stroke, functional ability, and cognitive impairment. We visualized the associations by using restricted cubic spline curves.

Results: A total of 200,717 participants with 718,822 observations are included in the baseline analysis. Compared to those without UI, both female and male participants with UI demonstrate a higher BMI and WC. Among females, the fully adjusted models show linear associations between BMI, WC, and UI (Ps < 0.001). However, we observe U-shaped associations of BMI, WC with UI among males. The lowest likelihood of having UI is found among male participants with a BMI between 24 and 35 kg/m.

Conclusions: Interventions aimed at preventing UI among older adults must take sex into account. Weight loss intervention could be an effective treatment among older females who are overweight and with obesity as well as older males with obesity rather than all older males.