Sacral Neuromodulation for Neurogenic Lower Urinary Tract Dysfunction

BACKGROUND: Neurogenic lower urinary tract dysfunction (NLUTD) is a highly prevalent and disabling condition; nevertheless, standard treatments often remain unsatisfactory. Sacral neuromodulation (SNM) is a well-established therapy for non-NLUTD, but there is a lack of randomized controlled trials to show benefit in patients with NLUTD. METHODS: For this sham-controlled, double-blind, multicenter trial, patients with refractory NLUTD (and intended SNM) were recruited at four Swiss SNM referral centers. After lead placement into the sacral foramina S3 (rarely, S4), all participants underwent SNM testing. If successful (≥50% improvement in key bladder diary variables), the neurostimulator was implanted for permanent stimulation. For 2 months, neuromodulation was optimized using subsensory stimulation with individually adjusted parameters. Thereafter, the neurostimulator remained on or was switched off (1:1 random allocation to group SNM ON or SNM OFF, respectively) for 2 months, followed by a neurourologic reevaluation. The primary outcome was success, as defined above, of SNM compared with baseline. RESULTS: Of 124 patients undergoing SNM testing, 65 (52%) had successfully improved lower urinary tract function. Of these, 60 patients (median age, 49.5 years; 43 women) were randomly assigned to the intervention. After 2 months of intervention, the SNM ON group demonstrated a success rate of 76%. In the SNM OFF group, 42% of patients showed sustained SNM effects despite their neurostimulator being switched off during the last 2 months (odds ratio, 4.35; 95% confidence interval, 1.43 to 13.21; P=0.009). During the entire study period, there were 11 adverse events (6 dropouts; no dropouts during the intervention phase). CONCLUSIONS: SNM effectively corrected refractory NLUTD in the short term in well-selected neurologic patients. (Funded by the Swiss National Science Foundation, Vontobel–Stiftung, Gottfried und Julia Bangerter–Rhyner Stiftung, Dr. Urs Mühlebach, and the Swiss Continence Foundation; ClinicalTrials.gov number, NCT02165774.)