Women With Metabolic Syndrome Face Higher Odds of Overactive Bladder: Study

China: A recent study published in Diabetology & Metabolic Syndrome has highlighted a strong link between metabolic syndrome (MetS) and the likelihood of developing overactive bladder (OAB), pointing to specific metabolic components as key contributors. The research, led by Zhihao Liu and colleagues from the Department of Cardiology at Tianjin First Center Hospital, analyzed data from the National Health and Nutrition Examination Survey (NHANES) and incorporated Mendelian randomization (MR) to assess potential causal relationships. The study analyzed NHANES data from 7,596 participants collected between 2005 and 2018 and revealed several key findings: Individuals with metabolic syndrome were more than twice as likely to experience overactive bladder compared to those without the condition (OR 2.27). Women with MetS had a 51% higher risk of developing OAB (OR 1.51), while no significant association was observed among men (OR 0.95). The findings suggest that gender may influence the relationship between MetS and OAB. Certain components of MetS, including increased body mass index (BMI), larger waist circumference, higher fasting blood glucose, and hypertension, were associated with a greater likelihood of OAB. Researchers noted that addressing these modifiable metabolic factors could help in managing OAB symptoms. To explore whether this relationship is causal, the authors conducted a Mendelian randomization analysis. While the results did not confirm a direct causal link between overall MetS and OAB symptoms, they indicated a possible causal role of certain metabolic components, such as obesity and elevated glucose levels. Sensitivity analyses showed no evidence of heterogeneity or horizontal pleiotropy, which supports the robustness of the findings. The researchers suggest that OAB, characterized by urinary urgency, frequent urination, and incontinence, significantly impacts quality of life, and its association with MetS adds another dimension to the clinical significance of metabolic health. Given that MetS already carries a high burden of cardiovascular and metabolic complications, the potential link to OAB underscores the need for comprehensive management strategies that address both conditions. However, the study acknowledged several limitations. The diagnosis of OAB in the NHANES dataset relied on self-reported questionnaire responses rather than clinical evaluation, raising the possibility of misclassification. Some covariates were also self-reported, which could introduce recall bias. Additionally, while the cross-sectional analysis included a racially diverse U.S. population, the MR component primarily focused on individuals of European ancestry, which may have limited its generalizability. Despite these limitations, the findings provide valuable insight into the interplay between metabolic and urinary health. The study concludes that while an overall causal relationship between MetS and OAB could not be established, certain components of metabolic syndrome may contribute to the development of OAB, highlighting the importance of targeting metabolic risk factors to improve bladder health. Reference: Liu, Z., Sun, X., Liu, C. et al. Relationship between metabolic syndrome and overactive bladder: insights from the NHANES and Mendelian randomization study. Diabetol Metab Syndr 17, 350 (2025). https://doi.org/10.1186/s13098-025-01883-6