Comparison of Different Treatment Outcomes for Refractory Overactive Bladder: A Systematic Review and Meta-Analysis

Background: Refractory overactive bladder (OAB) poses a significant clinical burden, often severely impacting quality of life (QoL). While intradetrusor onabotulinumtoxinA (BoNT-A) and sacral neuromodulation (SNM) are established therapeutic options, a direct comparison of their efficacy and safety profiles is essential to guide clinical decision-making. This study compares BoNT-A against placebo and SNM for the management of refractory OAB in women. Methods: Following PRISMA guidelines, PubMed, Scopus, CENTRAL, and Google Scholar were searched until February 2025 for randomized controlled trials (RCTs) and cohort studies on treatment alternatives for refractory OAB. Treatment outcomes at 3- (BoNT-A vs. placebo) and 6-month (BoNT-A vs. SNM) follow-up were analyzed. Odds ratios (ORs) and mean differences (MDs) were calculated for dichotomous and continuous variables, respectively, with heterogeneity assessed via I2 test. Study quality was evaluated using CASP tools. Results: Pooled data from 12 studies (2645 patients) indicated that BoNT-A significantly reduced urgency urinary incontinence (UUI) episodes compared to placebo (p = 0.02) and SNM (p = 0.0008). Additionally, a ≥75% reduction in UUI episodes was more likely with BoNT-A compared to both placebo (p < 0.00001) and SNM (p < 0.00001). Complete resolution of UUI was more likely with BoNT-A compared to placebo (p < 0.00001); however, when compared to SNM, the latter demonstrated a higher rate of complete UUI resolution (p < 0.00001). Patient-reported QoL did not show significant differences between BoNT-A and SNM (p = 0.2). Urinary tract infection (UTI) risk was higher with BoNT-A than both comparators. Conclusions: While BoNT-A offers robust symptom control, its safety profile necessitates careful patient selection. SNM remains a viable alternative for those prioritizing fewer adverse events. The study highlights the need for standardized outcome reporting, long-term cost-effectiveness analyses, and personalized treatment approaches.