Association Between Frailty and Short-Term Treatment-Related Adverse Events in Patients With Overactive Bladder

To evaluate whether frailty at treatment initiation is associated with treatment-related adverse events in patients with newly diagnosed overactive bladder (OAB).

This retrospective, single-center cohort study included 122 patients who initiated pharmacotherapy for OAB between April 2024 and January 2026. Frailty was evaluated using the Frailty Screening Index and classified as robust, prefrail, or frail. The primary outcome was treatment-related adverse events within 3 months, and independent predictors were identified using multivariable logistic regression. Longitudinal changes in OAB symptoms were examined using linear mixed-effects models.

During follow-up, adverse events occurred in 52 patients (42.6%), rising with frailty (4.7%, 40.0%, and 57.3% in robust, prefrail, and frail groups, respectively; p < 0.01 for trend). In multivariable analysis, frailty (odds ratio [OR] 2.97 per status increase, 95% confidence interval [CI] 1.45-6.52; p < 0.01), anticholinergic use (OR 7.96, 95% CI 2.94-24.46; p < 0.01), and baseline post-void residual volume (OR 1.22 per 10 mL increase, 95% CI 1.01-1.34; p = 0.02) were independently associated with adverse events; chronological age was not. Symptom improvement over time did not differ significantly by frailty status.

Frailty, rather than chronological age, was associated with short-term treatment-related adverse events among patients starting pharmacotherapy for OAB. Frailty assessment may help identify patients at higher risk of adverse events and support individualized, safety-conscious treatment decisions.