Long-term safety of overactive bladder medications in men receiving pharmacotherapy for benign prostatic enlargement: a real-world study using inverse probability of treatment weighting.

Abstract

Purpose: Despite guideline recommendations to use overactive bladder (OAB) medications in men with benign prostatic enlargement (BPE) presenting with storage symptoms, prescription rates remain low, possibly due to concern about worsening voiding symptoms. We evaluated the impact of OAB medications on safety outcomes in men receiving pharmacotherapy for BPE in a real-world setting.

Methods: We retrospectively reviewed 899 patients who received α-blockers, 5α-reductase inhibitors, or phosphodiesterase-5 inhibitors between April 2014 and December 2023. We assessed the association between adding antimuscarinics or β₃-agonists and acute urinary retention (AUR) using inverse probability of treatment weighting based on propensity scores; missing baseline covariates were handled by multiple imputation.

Results: Median follow-up was 28.7 months. At baseline, OAB users had lower PSA (2.5 vs. 3.6 ng/mL), smaller prostate volume (35 vs. 43 mL), and lower post-void residual (PVR) (12 vs. 35 mL) than non-users (all p < 0.001). 5α-reductase inhibitor use was less common in the OAB group (16.1% vs. 23.8%; p = 0.019). AUR incidence did not differ significantly between groups before (log-rank p = 0.054) or after weighting (hazard ratio 1.18; 95% CI 0.38-3.62; p = 0.776). Among OAB-treated patients, baseline AUR was significantly associated with discontinuation due to increased PVR (hazard ratio 9.10; 95% CI 1.81-45.6; p = 0.010).

Conclusion: In men with BPE on pharmacotherapy, addition of OAB medications was not associated with increased risk of AUR. Baseline AUR may predict subsequent discontinuation due to elevated PVR, indicating the need for careful monitoring in such patients.