Poster Presentations: AUGS Abstracts: 2005 26th Annual Scientific Meeting of The American Urogynecologic Society
INTRODUCTION AND OBJECTIVE:
Tension-free vaginal tape (TVT), the only sling procedure showing equal efficacy in a large, randomized, controlled trial when compared with the retropubic Burch procedure, and PVT are midurethral polypropylene sling procedures. To determine if the use of a generic piece of mesh using antegrade passage of needles (PVT) was equivalent in efficacy (1o outcome was the Anti-incontinence Surgery Response Score [AISRS]; 2o outcomes include the IIQ-7, UDI-6, and Global Assessment) and safety to the contemporary gold standard sling procedure (TVT), an equivalence study was designed to compare the outcomes.
One-tailed noninferiority tests were made for the outcomes and conclusions were based on a multivariate analysis. Baseline covariables were adjusted to prevent assignment bias or any baseline differences (none) resulting from nonrandomization of subjects into either a TVT or PVT procedure depending on the individual sling preference of the 9 surgeons. With a 1-year minimum follow up, outcomes were compared using a 5% significance level of testing the difference between means or proportions using a Δ value of 5% for AISRS proportion cured and 10% of the scale for questionnaires. Assuming a 90% cure rate for both groups, 226 total patients (113 patients in each group) were needed to have 80% power to conclude noninferiority of PVT. To evaluate safety, we compared intra- and postoperative complications.
After 191 patients were analyzed for the study (51.8% with TVT and 48.2% with PVT), PVT was found noninferior to TVT based on the 1o outcome of the AISRS (P=0.002). Of the covariables assessed, only age was significantly associated with the outcome (P=0.008). Higher age is associated with lower odds of success, with odds ratio (95% confidence interval) of 0.68 (0.52–0.90). For 2o outcomes, noninferiority of PVT was only found in the change of the IIQ score (P=0.038). For IIQ (P=0.005), UDI (P<0.001), and global (P=0.005), increasing age was significantly associated with less improvement in the score. For both the IIQ and UDI, SUI patients had significantly more improvement than patients with mixed incontinence. There was no difference in the proportion with at least one complication (P=0.90) or with any specific complication such as retention.
PVT is not inferior to TVT in regard to efficacy and safety and represents an inexpensive, generic equivalent to TVT.