External electrical stimulation compared with intravaginal electrical stimulation for the treatment of stress urinary incontinence in women: A randomized controlled noninferiority trial

AIMS: To compare the efficacy and safety of a neuromuscular external electrical stimulation device (INNOVO; "NMES") with an FDA-approved intravaginal device (iTouch sure; "comparator device") for the treatment of stress urinary incontinence (SUI). METHODS: This prospective, single-blind, multicenter, noninferiority study randomized women with SUI to treatment with the NMES or the comparator device for 12 weeks. The primary endpoint was the proportion achieving >50% reduction in pad weight from baseline to 12 weeks in the provocative pad weight test. RESULTS: Most subjects in both groups achieved >50% reduction in pad weight in the provocative pad test at week 12 (NMES 56.3%; comparator 63.0%), although noninferiority was not established. Significant improvements in pad tests, number of incontinence episodes, and pads used per day, and incontinence quality of life score were seen with both devices at week 12, with no clinically relevant between-group differences. Adverse events were predominantly mild/moderate and there were few discontinuations due to adverse events. The incidence of urinary tract/vaginal infections was higher with the comparator device than the NMES (7.7% versus 0%). The most common device-related adverse effect with the NMES was device discomfort (9.0%), which was generally manageable by modifying the stimulation intensity. CONCLUSIONS: The NMES significantly improved objective and subjective measures of SUI, although statistical noninferiority was not established. The NMES was well tolerated and associated with fewer urinary tract infections than the comparator. The NMES provides a safe, clinically effective, conservative treatment option for female SUI and a low-risk alternative to intravaginal devices.