Elevated urinary succinate in women with symptom-defined overactive bladder without clinically recognized cardiometabolic disease: a cross-sectional study

BACKGROUND: Overactive bladder (OAB) is a symptom-defined syndrome, and its metabolic correlates remain incompletely understood. This study investigated whether urinary tricarboxylic acid cycle metabolites differ between women with symptom-defined probable OAB and controls without clinically recognized cardiometabolic disease. METHODS: In this cross-sectional clinic-based study, women aged 18 years and older attending a gynecology outpatient clinic were enrolled. Participants with self-reported cardiometabolic disease or related medication use were excluded. Probable OAB was defined by an Overactive Bladder Awareness Tool Version 8 score of 8 or higher. Midstream urine samples were analyzed for succinate and malate by gas chromatography-mass spectrometry and normalized to urinary creatinine. Group comparisons, Spearman correlations, multivariable log-linear regression, sensitivity analyses, and exploratory receiver operating characteristic analyses were performed. RESULTS: A total of 186 women were included, comprising 81 with OAB and 105 controls. Women with OAB were older, had slightly higher body mass index, higher parity, and were more frequently postmenopausal. Urinary succinate and malate levels were higher in the OAB group. After adjustment for age, body mass index, parity, and menopausal status, OAB remained associated with higher urinary succinate (adjusted geometric mean ratio, 1.69; 95% CI, 1.34-2.12) and malate (1.25; 95% CI, 1.02-1.52). Succinate showed modest exploratory discrimination (AUC, 0.678), whereas malate showed limited discrimination (AUC, 0.560). CONCLUSIONS: Urinary succinate was higher in women with symptom-defined probable OAB even after adjustment for major demographic covariates, while the association with malate was weaker. These findings are hypothesis-generating and require confirmation in adequately powered, prospectively phenotyped cohorts with standardized metabolic, dietary, and urinary microbiome assessment.