Sustained effectiveness of percutaneous tibial nerve stimulation for overactive bladder syndrome: 2-year follow-up of positive responders.

INTRODUCTION AND HYPOTHESIS: The aim of the study was to describe effectiveness and safety of percutaneous tibial nerve stimulation (PTNS) at 2 years in women with overactive bladder (OAB) syndrome unresponsive to pharmacotherapy. METHODS: Of 30 women who had initial positive response to PTNS, 23 continued to receive maintenance treatment and were reassessed at 2 years using bladder symptom diaries and the Incontinence Impact Questionnaire (IIQ-7). They were also questioned on acceptability and any adverse effects of long-term peripheral neuromodulative treatment. RESULTS: Data from 23 women were available and 7 had been lost to follow-up. With maintenance treatment, the median nocturnal frequency at 2 years had decreased by 57 % (3.5 to 1.5 times/night), while the median IIQ-7 had reduced from 30.4 to 21.5 (both p<0.01) compared to pre-treatment baseline. Median nocturnal frequency and IIQ-7 scores at 2 years were comparable to those documented after initial response to treatment at 6 weeks, suggesting that maintenance therapy continued to suppress OAB symptoms. Daytime frequency and daily urgency incontinence episodes at 2 years were statistically similar to those documented at 6 weeks and remained lower than pre-treatment baseline (6.5 vs 11.8 and 2.0 vs 3.5, respectively, p<0.05). The women received a median of 8.42 treatments per year and the median length between treatments was 64.3 days. Apart from hypaesthesia in the toe of one responder lasting for 4 months, there were no reported side effects. CONCLUSIONS: Women receiving PTNS for intractable OAB syndrome reported significant symptom relief at 2 years. This remains a safe mode of second-line treatment with excellent durability.