Social determinants and lifestyle-related factors associated with incident urinary incontinence among adults aged 50 years and older: a multicohort study.

BACKGROUND: Urinary incontinence (UI) affects a substantial proportion of middle-aged and older adults worldwide. We examined the associations of social determinants of health (SDOH) and lifestyle-related factors with incident UI in three national aging cohorts to identify factors associated with UI risk. METHODS: We analyzed longitudinal data from the Health and Retirement Study (HRS; United States), the English Longitudinal Study of Ageing (ELSA; England), and the China Health and Retirement Longitudinal Study (CHARLS; China). Composite SDOH scores and healthy lifestyle indexes were constructed from five harmonized domains or factors, each ranging from 0 to 5. Incident UI was the primary outcome. Cohort-specific survey-weighted Cox proportional hazards models were fitted, and estimates were pooled using random-effects meta-analysis. RESULTS: The analysis included 11,126 participants aged 50 years or older, with follow-up ranging from 8 to 10 years. Weighted UI incidence was 28.6% in HRS, 23.1% in ELSA, and 19.7% in CHARLS. The composite SDOH score was not consistently associated with incident UI (HR = 0.97, 95% CI: 0.92-1.01). A higher healthy lifestyle index was associated with lower UI risk (HR = 0.87, 95% CI: 0.81-0.92). Sleep problems (HR = 1.43, 95% CI: 1.31-1.55), higher body mass index (BMI; HR = 1.02, 95% CI: 1.01-1.03), and postsecondary education (HR = 1.37, 95% CI: 1.17-1.61) were associated with higher UI risk, whereas regular physical activity was associated with lower risk (HR = 0.78, 95% CI: 0.70-0.87). Mediation analyses suggested that sleep problems partially mediated the association between physical activity and incident UI. CONCLUSION: In this multi-cohort longitudinal study of adults aged 50 years and older, the composite SDOH score showed no consistent association with incident UI, whereas a higher healthy lifestyle index was associated with lower UI risk. Physical activity, BMI, and sleep problems may help identify individuals at higher UI risk, although sleep problems may also reflect underlying health conditions. These findings support lifestyle management as a potential target for UI prevention.