Association Between Cardiovascular Health (Life’s Crucial 9) and Stress Urinary Incontinence in Women: The Mediating Role of Oxidative Stress Factors (NHANES 2005-2018)

Objective: Cardiovascular disease and stress urinary incontinence (SUI) may be interconnected. This study aimed to investigate whether indicators of oxidative stress play a moderating role in the relationship between SUI and Life’s Crucial 9 (LC9), a cardiovascular health (CVH) index incorporating mental health. Methods: Data from 5,292 US women aged 20 and older were analyzed using the National Health and Nutrition Examination Survey database from 2005 to 2018. The LC9 score, which was determined by averaging the sum of the eight LE8 component scores and the depression score. To assess the relationship between LC9 and SUI, restricted cubic splines (RCS) analysis and weighted multivariate logistic regression were employed. Additionally, mediation analysis was conducted to evaluate the indirect impact of oxidative stress markers on this relationship. Results: After adjusting for potential confounders, individuals in the second and highest tertiles of LC9 exhibited significantly higher odds of SUI odds ratios (OR) for each 1-point increase were 0.817 and 0.765; 95% confidence intervals (CI), 0.673– 0.993 and 0.600– 0.975, respectively. Furthermore, RCS results suggested an approximately linear dose-response relationship between LC9 and the prevalence of SUI. Additionally, mediation analysis indicated that oxidative stress biomarkers, specifically bilirubin and uric acid, mediated the relationship between LC9 and SUI, with mediation proportions of 2.22% and 2.64%, respectively ( P < 0.05). Conclusion: The present study suggests that higher LC9 scores, which represent ideal CVH, are significantly associated with reduced odds of SUI. Additionally, oxidative stress biomarkers may play a mediating role in this relationship. Keywords: life’s crucial 9, stress urinary incontinence, cardiovascular health, oxidative stress, NHANES