Risk factors related to acupuncture response in postmenopausal women with stress urinary incontinence: Secondary analysis of a randomized controlled trial

Postmenopausal women are at a higher risk of stress urinary incontinence (SUI). In a previous trial, electroacupuncture (EA) was shown to be an effective treatment for women with SUI. Here we present a secondary analysis to investigate the specific factors associated with response to acupuncture therapy among postmenopausal women with SUI. We conducted secondary analysis of data from a multicenter randomized controlled trial. This trial included a baseline period of 1 week and a treatment period of 6 weeks with electroacupuncture (EA) or sham electroacupuncture (SA). The patients were randomly assigned to 2 groups (EA group or SA group). Participants who showed a decrease in urine leakage by at least 50% from baseline level, as measured by 1-hour pad at week 6, were defined as responders. Baseline characteristics associated with response to acupuncture therapy (e.g., demographic, comorbidities, and lifestyle-related factors) were identified by logistic regression analysis and the interactions between treatment assignment and baseline characteristics assessed. This analysis included a total of 349 postmenopausal women, of whom 137 (39.3%) were classified as responders. Response rate in the EA group was significantly higher than that in the SA group (60.9% vs 18.9%, respectively; P < .001). On multivariable logistic regression analysis, only “mean number of urine pads used before treatment” remained a significant predictor of response to therapy (EA or SA). Greater weekly mean number of urine pads used before treatment showed a correlation with non-response to therapy, as the likelihood of clinical response reduced by 5.26% with increase in the weekly mean number of urine pads used (odds ratio 0.947, 95% confidence interval 0.902–0.993; P = .020). The interaction terms were not statistically significant. Postmenopausal women with SUI who used fewer number of pads per week before treatment were more likely to respond to therapy. This study provides valuable insights for pretreatment selection of women with SUI. Specific factors related to the therapeutic effects of acupuncture were not identified and need to be explored in future studies. Trial registration: Clinical Trials.gov: NCT01784172.