According to a systematic review, sacral and percutaneous tibial neuromodulation improves symptoms in many patients with non-neurogenic lower urinary tract dysfunction

Despite scarce data, especially on long-term outcomes, sacral neuromodulation (SNM) and the less invasive percutaneous tibial nerve stimulation (PTNS) are commonly considered for patients with lower urinary tract dysfunction who have failed conservative treatments.

Dr. Manuela Tutolo from University Hospitals Leuven, Belgium et al. investigated the efficacy and safety of neuromodulation for non-neurogenic lower urinary tract dysfunction in a systematic review. Each of the 21 included studies (1998-2017) followed a minimum of 20 patients for at least six months.

In nine studies of SNM for overactive bladder, improvement of at least 50% in leakage episodes ranged from 29% to 75%, and overall dry rates ranged from 47% to 56%, according to the European Urology online report. Failure rates ranged from 4% to 34%, but they were registered at different time points and in groups with differing symptom severity.

In one study, SNM was associated with a 43% success rate in patients with interstitial cystitis/bladder pain syndrome. In two studies, SNM had success rates of 53% to 73%, depending on the outcome measured, in patients with chronic non-obstructive urinary retention.

Similarly, PTNS was associated with success rates in four prospective studies of overactive bladder ranging from 56% to 59%, but the definitions of success differed among the studies.

In two studies of interstitial cystitis/bladder pain syndrome, PTNS yielded improvement in up to 67% of patients, depending on the outcome measured. In the only study of chronic non-obstructive urinary retention, PTNS was associated with significant voiding improvement in 41% of patients.

Neither procedure yielded major complications. Between 15% and 42% of SNM patients reported pain at the implant site, and implant site infections developed in 3% to 6.1% of SNM patients.

“Our review of the literature is in line with current guidelines in which SNM can be offered to patients not responsive to standard treatment, with high success rates, before more aggressive surgery,” the researchers conclude.

“It has to be once again underlined that the majority of studies included are prospective or retrospective cohort studies, rendering the evidence for neuromodulation in lower urinary tract dysfunction weak. These results support the need for long-term follow-up and prospective randomized trials, with adequate numbers and validated questionnaires.”