Antimuscarinic Drugs for Overactive Bladder Tied With Higher UTI Risks

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Results are from a meta-analysis of 33 trials involving 35,939 patients with overactive bladder.

Overactive bladder treatment using antimuscarinic drugs increases the risks for urinary tract infection (UTI) and lower urinary tract symptoms (LUTS), a new study finds.

Nobuhiro Haga, MD, PhD, of Fukuoka University in Japan, and colleagues performed a meta-analysis of 29 placebo-controlled trials of antimuscarinic agents and 9 placebo-controlled trials of beta 3-adrenoceptor agonists involving 35,939 patients with overactive bladder, published during 2002 to 2021. All trials had low risk of bias.

At 1-3 months after treatment, UTI risk was a significant 23% higher among patients receiving antimuscarinic drugs compared with placebo, the investigators reported in The Journal of Urology. The broad UTI outcome encompassed upper UTI, acute cystitis requiring treatment, as well as febrile UTI. Use of antimuscarinic drugs also was significantly associated with a 2.9-fold increased risk for urinary retention (few patients required catheterization), dysuria, and/or increased residual urine volume, factors involved in UTI pathogenesis. Antimuscarinic drugs included imidafenacin, solifenacin, tolterodine, fesoterodine, darifenacin, and trospium of various doses.

Use of beta 3-adrenoceptor agonists was not associated with any of these risks, the investigators reported. Drugs in this class included solabegron, mirabegron, and vibegron.

“To prevent urinary tract infection emergence, beta 3-adrenoceptor agonists might be safer than antimuscarinic agents,” according to Dr Haga’s team. The investigators noted that UTI causes not only LUTS, but pyelonephritis, which can lead to kidney dysfunction. They suggested that older adults and patients with diabetes might be good candidates for beta 3-adrenoceptor agonists due to their increased risks for UTI. Women with strong overactive bladder symptoms and men without bladder outlet obstruction due to benign prostatic hyperplasia or other conditions might be good candidates for antimuscarinic agents.

The investigators acknowledged that a direct comparison between antimuscarinics and beta 3-adrenoreceptor antagonists in a randomized trial would be more reliable and informative than a meta-analysis.


Tsubouchi K, Arima H, Abe M, et al. Effect of pharmacotherapy for overactive bladder on the incidence of and factors related to urinary tract infection: a systematic review and meta-analysis. J Urol. 209(4):665-674. doi:10.1097/JU.0000000000003209

This article originally appeared on Renal and Urology News