3-Year Followup of a New Implantable Tibial Nerve Stimulator for the Treatment of Overactive Bladder Syndrome

Purpose: We evaluated the 3-year safety and efficacy of the BlueWind Medical RENOVA™ iStim system for the treatment of overactive bladder syndrome.

Materials and methods: All patients who previously underwent implantation with the RENOVA system were offered continued participation. The primary long-term study end point was to evaluate the safety profile based on incidence of serious adverse events (system and/or procedure related), which was measured by the impact and frequency of serious adverse events. The secondary end points included clinical improvement compared to baseline and quality of life improvement compared to baseline at 36 months, which was measured by 3-day voiding diary and quality of life questionnaires at certain time points.

Results: Of the 34 patients with overactive bladder syndrome who previously underwent implantation with the RENOVA system 20 consented to continuation in this 3-year followup study. Mean patient age was 56.1 years and 80% (16) of the study cohort was female. The overall treatment success rate was 75% at 36 months in the per protocol (16) and the intent to treat (20) analyses. In total, 73% of the patients reported improvement in health related quality of life scores above the minimal important difference of 10 points.

Conclusions: This 3-year followup study using the BlueWind RENOVA iStim system for the treatment of overactive bladder syndrome symptoms confirms the long-term good safety profile with no technical failures reported. Lasting treatment efficacy is mirrored by a sustained positive impact on patient quality of life.