Sacral neuromodulation (SNM) represents a promising treatment option for women with detrusor underactivity (DU) and refractory overactive bladder (OAB), with success rates reaching 70% and 90%, respectively. Success rates in men, however, are not well described. Men with neurogenic bladder dysfunction and bladder outlet obstruction (BOO) may benefit from BOO procedures in terms of voiding symptoms, but studies have shown that detrusor contractility may not necessarily improve, especially with longstanding BOO. The aim of this study was to examine SNM success rates in men with a focus on men with BOO requiring prior BOO procedures.

We retrospectively reviewed all male patients with lower urinary tract dysfunction (LUTD) who underwent implantation of a sacral neuromodulator (SNM) from the periods of July 2021 to August 2023. Baseline data was collected for each patient including age of implantation, ethnicity, race, comorbidity status, urinary symptoms, and urinary catheter use. Urodynamic studies were used to classify type of LUTD. Success after SNM implantation was defined as subjective improvement in symptoms [frequency, urgency, nocturia, improved bladder emptying, or a decreased need for urinary catheterization] at subsequent postoperative visits. Patients were further stratified by whether they had a diagnosis of BOO and subsequently underwent at least one BOO procedure prior to SNM implantation. Rates of success were reported between the two groups.

In total, 21 males underwent placement of a SNM device during the study period, with average age 64.3 (±17.7). Approximately 33%, 43%, and 14% of patients had a history of hypertension, neurological disorder, or diabetes, respectively. Of note, 10 (48%) patients were classified with DU and 10 (48%) with OAB as their primary LUTD. Nine (43%) reported prior urinary catheter use, and the average postvoid residual at initial visit was 306.3 (±277.0 mL). Overall, 14/21 (67%) of patients reported improvement in symptoms after SNM implantation. Eleven (52%) patients underwent ≥1 BOO procedures prior to SNM implantation with the average latency between procedures being 14.0 (±14.4) months. Of these, 45% of them reported improvement in their voiding symptoms. In the remaining 10 patients without prior BOO procedures, 8 (80%) reported improvement in their symptoms after implantation. In patients with DU and prior BOO procedures, only 3/8 (38%) reported improvement.

Men with a history of BOO requiring procedures to relieve obstruction had lower symptom improvement rates with SNM than those without. This finding was more pronounced in patients with concomitant DU as the underlying LUTD. Men without BOO had success rates similar to those seen in women.

Men with a history of BOO requiring BOO procedures have a lower success rate with SNM, possibly due to longstanding effects of BOO on detrusor contractility. These results can allow clinicians to offer tailored counseling based on prior history for men considering treatment with SNM.

Thomas A.W., Cannon A., Bartlett E., Ellis-Jones J., Abrams P. The natural history of lower urinary tract dysfunction in men: The influence of detrusor underactivity on the outcome after transurethral resection of the prostate with a minimum 10-year urodynamic follow-up. BJU Int. 2004;93:745–750. doi: 10.1111/j.1464-410X.2003.04719.x.