Purpose: We evaluated whether polyacrylamide hydrogel is noninferior to tension-free vaginal tape to treat women with primary stress urinary incontinence.
Materials and methods: In this controlled noninferiority clinical trial patients with primary stress urinary incontinence were randomized to tension-free vaginal tape or polyacrylamide hydrogel treatment. The primary outcome was patient satisfaction and secondary outcomes were effectiveness in reducing urinary leakage and complications at 1-year followup. For statistical power significance was considered at 5%, power was set at 80% and the noninferiority limit was 20% with a 10% expected dropout rate.
Results: A total of 224 women with primary stress urinary incontinence entered the study between September 28, 2015 and March 1, 2017. Of the women 111 were randomized to tension-free vaginal tape and 113 were randomized to polyacrylamide hydrogel. At 1 year a satisfaction score of 80 or greater on a visual analogue scale of 0 to 100 was reached in 95.0% and 59.8% of patients treated with tension-free vaginal tape and polyacrylamide hydrogel, respectively. Thus, polyacrylamide hydrogel did not meet the noninferiority criteria set in our study. As secondary outcomes, the cough stress test was negative in 95.0% of tension-free vaginal tape cases vs 66.4% of polyacrylamide hydrogel cases (difference 28.6%, 95% CI 18.4-38.5). However, most perioperative complications, including those in 19 tension-free vaginal tape cases vs 3 polyacrylamide hydrogel cases (difference 16.0%, 95% CI 7.8-24.9), and all 6 reoperations due to complications (difference 5.9%, 95% CI 1.2-12.4) were associated with tension-free vaginal tape.
Conclusions: Mid urethral tension-free vaginal tape slings were associated with better satisfaction and cure rates than polyacrylamide hydrogel in women with primary stress urinary incontinence. However, complications were mainly associated with tension-free vaginal tape. Thus, tension-free vaginal tape should be offered as first line treatment in women who expect to be completely cured by the initial treatment and are willing to accept the complication risks. Since polyacrylamide hydrogel treatment also provides high satisfaction and cure rates, women with primary stress urinary incontinence can be offered polyacrylamide hydrogel as an alternative treatment.
Keywords: hydrogels; risk; stress; suburethral slings; urethra; urinary incontinence.