The Effects of Antimuscarinic Treatments in Overactive Bladder: an Update of a Systematic Review and Meta-analysis

Context: Antimuscarinic agents are currently the first-line pharmacotherapy for overactive bladder.

Objectives: A systematic review published in 2005 was updated, including data on a newly licensed antimuscarinic (fesoterodine). The primary aim of this study was to systematically review evidence on the efficacy of licensed administration of antimuscarinic treatments in overactive bladder from randomised controlled trials. Secondary aims were to review evidence on tolerability and safety and health-related quality of life (HRQL).

Evidence Acquisition: All relevant data sources from randomised controlled trials were searched, and two independent reviewers considered publications for inclusion and extracted relevant data. Meta-analysis was used to pool efficacy, tolerability, safety, and HRQL outcomes by treatment. Efficacy was measured by continent days, mean voided volume, urgency episodes, and micturition frequency. Tolerability and safety were measured by means of adverse event and withdrawal rates. HRQL was measured by various instruments.

Evidence Synthesis: An additional 1118 references were retrieved with data on 83 studies extracted. Antimuscarinics were found to be more effective than placebo. Tolerability was good; few of the antimuscarinics were found to have significantly higher withdrawal rates in comparison to placebo. No serious adverse event for any product was statistically significant compared to placebo. Dry mouth (mild, moderate, severe) was the most commonly reported adverse event (29.6% on treatment vs 7.9% on placebo), followed by pruritus (15.4% on treatment vs 5.2% on placebo). Improvements were seen in HRQL with treatment by darifenacin, fesoterodine, oxybutynin transdermal delivery system, propiverine extended release (ER), solifenacin, tolterodine ER and immediate release, and trospium. Limitations of the study include restrictions on the types of patients typically included in overactive bladder trials and topics that have not been adequately addressed in the current antimuscarinic literature.

Conclusions: Antimuscarinics are efficacious, safe, and well-tolerated treatments that improve HRQL. Profiles of each drug and dosage differ and should be considered in making treatment choices.