A systematic review and meta-analysis of effectiveness and safety of therapy for overactive bladder using botulinum toxin A at different dosages.

[PURPOSE] To assess the effectiveness and safety of botulinum toxin A (BTX-A) at different dosages for overactive bladder (OAB).

[MATERIALS AND METHODS] The MEDLINE, EMBASE, and Cochrane Controlled Trials Register databases were searched through November 3, 2016 to identify relevant randomized controlled trials (RCTs).

[RESULTS] Eleven studies were identified in this meta-analysis. Compared with placebo, the urinary incontinence (UI) episodes per week as the primary outcomes, urodynamic parameters including maximum cystometric capacity (MCC), and maximum detrusor pressure (MDP) for neurogenic detrusor overactivity (NDO) at 6 weeks, and for idiopathic detrusor overactivity (IDO) at 36 weeks were evaluated. These and other outcomes for effectiveness of BTX-A at different dosages in two observation periods indicate that a dose greater than 50 U is significantly more effective for certain symptoms of OAB compared with placebo. However, there were no significant differences between some dosages. Compared with placebo, the outcomes of total adverse events for NDO and for IDO show that doses of 300 U and 200 U for NDO are associated with more complications.

[CONCLUSIONS] In consideration that the treatments of BTX-A were with minimal, local, and manageable adverse effects, this meta-analysis demonstrates that BTX-A 200 U is recommended for management of NDO for short-term treatment for there was no significant difference from the larger dose of 300U. The short-term efficacies of BTX-A for IDO remain to be investigated.