Results of a prospective, randomized, multicenter study evaluating sacral neuromodulation with InterStim therapy compared to standard medical therapy at 6-months in subjects with mild symptoms of overactive bladder

Aims: This prospective, randomized, multicenter trial evaluated the 6-month success rate of sacral neuromodulation (SNM) with InterStim® Therapy versus standard medical therapy (SMT) for overactive bladder (OAB).

Methods: Enrolled subjects discontinued OAB medications prior to and during baseline data collection and were randomized 1:1 to SNM or SMT. Subjects had bothersome symptoms of overactive bladder (OAB) including urinary urge incontinence (≥2 leaks/72 hr) and/or urgency-frequency (≥8 voids/day). Subjects failed at least one anticholinergic medication, and had at least one medication not yet attempted. The primary objective was to compare OAB therapeutic success rate at 6 months between SNM and SMT.

Results: Overall, 147 subjects were randomized (70 to SNM and 77 to SMT); 93% were female and mean age was 58. The primary intent to treat analysis showed OAB therapeutic success was significantly greater in the SNM group (61%) than the SMT group (42%; P = 0.02). In the as treated analysis, OAB therapeutic success was 76% for SNM and 49% for SMT (P = 0.002). The SNM group showed significant improvements in quality of life versus the SMT group (all P < 0.001) and 86% of SNM subjects reported improved or greatly improved urinary symptom interference score at 6 months, compared to 44% for SMT subjects. The device-related adverse event rate was 30.5% and the medication-related adverse event rate was 27.3%.

Conclusions: This study demonstrates superior objective and subjective success of SNM compared to SMT. SNM is shown to be a safe and effective treatment for OAB patients with mild to moderate symptoms. Neurourol. Urodynam. 34:224-230, 2015. © 2014 Wiley Periodicals, Inc.