Association between metabolic syndrome and overactive bladder in American adults: A cross-sectional study from NHANES 2005–2018

The purpose of this study was to investigate the relationship between metabolic syndrome (MetS) and overactive bladder (OAB). This research involved a cohort of 11,078 individuals enrolled from the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2018. We applied restricted cubic spline analysis and weighted multivariable logistic regression to assess the association between MetS and OAB, supplemented by subgroup analyses to reinforce these findings. After full multivariable adjustment, MetS was associated with OAB (odds ratio [OR] = 1.30; 95% confidence interval [CI], 1.12-1.50). When stratified by severity, only moderate MetS was associated with a significantly higher risk of OAB compared to no MetS (OR = 1.61; 95% CI, 1.31-1.98), whereas the association for severe MetS was not statistically significant (OR = 1.31; 95% CI, 0.93-1.84). This is consistent with a significant nonlinear dose-response relationship (P for nonlinearity < .001), where the risk of OAB plateaus at the highest levels of MetS severity. Subgroup analyses were performed to explore the consistency of this association. A trend toward a stronger association was observed in females (OR = 1.60; 95% CI, 1.35-1.89) compared to males (OR = 1.25; 95% CI, 0.97-1.60), with a P-value for interaction of .137. The association also varied by race and appeared to attenuate with increasing age, though the formal test for interaction by age was not statistically significant (P = .061). Our study results indicated a nonlinear association between the MetS score and the risk of OAB (P for nonlinearity < .001). However, further research is needed to confirm our findings.