A retrospective cross-sectional study on the nonlinear association between cardiovascular health and overactive bladder in a national population-based cohort.

OBJECTIVE: The relationship between cardiovascular health (CVH) and overactive bladder (OAB) remains incompletely elucidated. We aimed to examine the association between CVH, assessed using the Life's Essential 8 (LE8) score, and the presence and severity of OAB, as well as its related symptoms, in a nationally representative sample. METHODS: This cross-sectional study included 6042 participants from the National Health and Nutrition Examination Survey. CVH was categorized as low (0-49), moderate (50-79), or high (80-100) based on LE8 scores. Multivariable-adjusted logistic and linear regression models were used to assess associations with OAB, urgency urinary incontinence (UUI), and nocturia. Restricted cubic splines and segmented regression models were employed to evaluate nonlinear relationships. Mediation analyses were conducted to explore potential biological pathways. RESULTS: A pronounced inverse gradient was observed between LE8 scores and OAB outcomes. In fully adjusted models, participants with high CVH had significantly lower odds of OAB [odds ratio (OR) 0.59, 95% confidence interval (CI): 0.38-0.91; P-trend < 0.001] compared to the low CVH group. Each 10-point increase in LE8 score was associated with a 13% reduction in OAB odds (OR 0.87, 95% CI: 0.80-0.95). Nonlinear analyses revealed threshold effects at LE8 scores around 73 for OAB and UUI, beyond which protective associations plateaued. Causal mediation analyses indicated that systemic inflammation (LnSII) and plasma osmolality mediated 4.8 and 12.8% of the association, respectively. Among LE8 components, BMI and sleep health were the strongest contributors to urological outcomes. CONCLUSION: Better CVH, as measured by LE8, is nonlinearly and inversely associated with OAB and related symptoms, partially mediated by inflammation and osmolality. Metabolic and sleep factors emerged as dominant contributors, highlighting potential targets for prevention and intervention.