Evaluation of progression from first to second stage sacral neuromodulation and unplanned device removal

Objective: Sacral neuromodulation (SNM) is an advanced treatment option for patients with refractory overactive bladder (OAB) symptoms, urinary retention, and bowel disorders; it is usually performed in 2 separate procedures. This study aims to determine a cohort’s progression rate from stage 1 to 2 and predict factors for progression and unplanned device removal or revision. Material and methods: A retrospective review was conducted in patients who underwent SNM at a single institution between June 2012 and May 2019. Progression rates from stage 1 to 2, patient characteristics, and indications for unplanned SNM removal or revision were recorded. Chi-square, Mann-Whitney U, and Fisher’s exact tests were used for data analysis. Results: A total of 128 patients underwent SNM for 1 or more of the following diagnoses: OAB (n=103), urinary retention (n=15), neurogenic bladder dysfunction (n=4), fecal incontinence (n=2), and constipation (n=4). The progression rate to stage 2 was 92.2% (118/128). Patients who failed to progress to stage 2 had ad-ditional diagnoses other than OAB, such as urinary retention or bowel disorders (p=0.007). Fifteen patients (12.7%) required SNM removal or revision within 4 years of surgery. Among these patients, the body mass index was significantly lower (p=0.036). Conclusion: Most patients (92.2%) progressed to stage 2. Patients with only OAB symptoms had a higher progression rate to stage 2. Single full-stage procedures may be considered in select patients to reduce mor-bidity, time, and costs.