Electroacupuncture versus solifenacin for women with urgency-predominant mixed urinary incontinence: a protocol for a three-armed non-inferiority randomized controlled trial

Background: Among women suffering from urinary incontinence (UI), about one-third are diagnosed with mixed urinary incontinence (MUI), among which urgency-predominant MUI causes more shame and inconvenience to patients. The treatments for urgency-predominant MUI have limited guidelines and previous studies have indicated that electroacupuncture (EA) might be a safe and effective option. The present study aims to evaluate the effect of EA on women with urgency-predominant MUI. Methods: The study is a multicentered, three-armed, non-inferiority randomized clinical trial. A total of 282 female patients with urgency-predominant MUI will be randomly divided into three groups, namely the EA group, sham electroacupuncture (SA) group, and solifenacin treatment group at a ratio of 1:1:1. Thirty-six sessions of acupuncture treatment over 12 weeks and solifenacin treatment over 36 weeks will be provided. The primary outcome will be the decrease of urgency urinary incontinence (UUI) episodes after 12-week treatment. Secondary outcomes will include changes in incontinence episodes, urinary frequency, urgency, severity of symptoms, and influence on quality of life, assessed using the International Consultation on Incontinence Questionnaire Short Form (ICIQ SF) and Overactive Bladder Questionnaire Short Form (OAB-q SF). All patients will be continuously followed up until week 36 and their allocations will be statistically analyzed. Discussion: Though placebo of solifenacin is rather difficult to access and all patients in the trial cannot be fully blinded, the present study will serve as an introduction of three-armed, randomized, non-inferiority, and sham acupuncture-controlled clinical trials to the acupuncture field, in an attempt to compare the effects of EA and solifenacin for treating women with urgency- predominant MUI.