Synthetic versus non-synthetic slings for female stress and mixed urinary incontinence: A systematic review and meta-analysis

Am J Obstet Gynecol. 2024 Mar 1:S0002-9378(24)00420-4. doi: 10.1016/j.ajog.2024.02.306. Online ahead of print.

Abstract

Objective: To systematically review objective and subjective success, and surgical outcomes of sub-urethral sling surgery for female patients with stress or mixed urinary incontinence (SUI, MUI) using synthetic vs. non-synthetic material with corresponding surgical approach (retropubic, RP or transobturator, TO).

Data sources: We systematically searched Medline, Embase, EBM Reviews, ClinicalTrials.gov and Web of Science Core Collection using standardized medical subject headings, no date restrictions (Prospero registered). We double-screened studies and used backward citation chaining.

Study eligibility: We included peer-reviewed randomized controlled trials and prospective or retrospective comparative studies examining outcomes of RP or TO synthetic vs non-synthetic (autologous, allograft, xenograft) slings for female SUI or MUI, with available English or French full text. We excluded minislings (single insertion point). We allowed slings for recurrent SUI or MUI, and slings concomitant with prolapse surgery, with at least 6 weeks of postoperative follow-up. We excluded systematic reviews, meta-analyses, review studies, case-control studies, case reports, studies that did not describe surgical approach or material, and studies of combination slings.

Study appraisal: We evaluated study quality using the Cochrane Risk of Bias Tool for randomized controlled trials and the Newcastle-Ottawa Scale for observational studies. We used pooled relative risk (RR) with 95% confidence intervals (CI) to estimate effect of sling material type on each outcome through meta-analysis and meta-regression as appropriate.

Results: We screened 4341 abstracts, assessed 104 full-texts and retained 35 manuscripts (30 separate studies). For RP synthetic vs non-synthetic, there was no difference in number of objectively or subjectively continent patients. Reoperation for SUI and overall was higher for non-autologous RP slings compared to synthetic. RP synthetic vs autologous slings were associated with higher subjective continence in populations with ≥ 25% recurrent SUI (RR 1.27, 95% CI 1.12-1.43). For TO synthetic vs non-synthetic, there were no differences in continence. Subjective satisfaction was better in the TO synthetic group compared to autologous (RR 1.42, 95% CI 1.03;1.94).

Conclusions: Synthetic and non-synthetic slings have comparable objective and subjective success, with differences in operative outcomes and complications generally in favour of synthetic material.

Keywords: autologous fascia; mixed urinary incontinence; retropubic sling; stress urinary incontinence; synthetic; transobturator sling.