Long-Term Functional Outcomes of S3 Sacral Neuromodulation for the Treatment of Idiopathic Overactive Bladder

ObjectivesTo assess the long-term functional outcomes of sacral neuromodulation (SNM) in the treatment of refractory idiopathic overactive bladder (IOAB) and to determine predictive factors for success. Materials and MethodsTo obtain long-term data, all consecutive patients suffering from IOAB and treated by SNM at a single tertiary care center between December 1996 and December 2004 were included. Data regarding patient demographics, past medical, and surgical history, bladder diary, complications as well as device revision and removal rates were collected. Success was defined as an improvement50% of any clinical parameter. ResultsOverall, 34 patients, with a median age of 57.8 years (IQR 44.8-65.7) were included. Immediately after definitive implantation, 2 (6%) patients were lost to follow-up. After a median follow-up of 9.7 years (IQR 4.7-12.0), SNM was considered successful in 20 (63%) patients. Mean amount of protections used per 24 hours significantly decreased (4.1 preoperatively vs. 1.8 at the last follow-up visit, p=0.02). Devices were removed in 2 (6%) patients due to pain and lack of efficacy. Twenty-two revision surgeries were performed in 15 (47%) patients. First revision surgery occurred after a mean of 6.2 years ( 3.1). Revision surgeries were mainly performed for end of battery life/device dysfunction (n=18, 82%). No significant predictor for success was identified. ConclusionsWith a median follow-up time of 9.7 years, this retrospective SNM study reports a 63% efficacy rate ( 50% improvement) for the treatment of refractory IOAB. Moreover, it is a well-tolerated and minimally invasive therapy.