Management of Overactive Bladder With OnabotulinumtoxinA: Systematic Review and Meta-analysis

To evaluate the efficacy and safety of OnabotulinumtoxinA treatment in the management of overactive bladder syndrome.

A systematic review of the literature and meta-analysis was performed including randomized controlled clinical trials that compared the use of OnabotulinumtoxinA with the use of placebo, antimuscarinic medication, or different doses of OnabotulinumtoxinA. Eleven studies met inclusion criteria and did not have any exclusion criteria. Primary outcome is improvement of urge incontinence, urinary frequency, and urinary urgency. Secondary outcomes are adverse events (urinary tract infection, urinary retention) and quality of life. Outcomes were evaluated after a 12-week follow-up period. Independent evaluation of the study's quality using the CONSORT (Consolidated Standards of Reporting Trials) tool was made. Analysis was performed in Review Manager 5.2.

Compared with placebo, OnabotulinumtoxinA significantly decreased the number of episodes of urge incontinence. Urinary tract infection was more frequent in patients treated with OnabotulinumtoxinA than in patients treated with placebo. Frequency of urinary retention was not significantly different between patients treated with 100 IU OnabotulinumtoxinA dose and those treated with higher doses. Quality of life was assessed with different instruments in 3 of the studies; this implied a limitation because it was not possible to compare these data.

Intravesical injections of OnabotulinumtoxinA compared with placebo showed a statistically significant improvement in the treatment of overactive bladder. Adverse events were more frequent among patients treated with OnabotulinumtoxinA. This meta-analysis takes into account only randomized placebo controlled trials.