Synthetic vs nonsynthetic slings for female stress and mixed urinary incontinence: a systematic review and meta-analysis
Data sources: We systematically searched Medline, Embase, EBM Reviews, ClinicalTrials.gov, and Web of Science Core Collection using standardized Medical Subject Headings (MeSH) without date restrictions (PROSPERO-registered). We double-screened studies and used backward citation chaining.
Study eligibility criteria: We included peer-reviewed randomized controlled trials and prospective or retrospective comparative studies examining outcomes of retropubic or transobturator synthetic vs nonsynthetic (autologous, allograft, or xenograft) slings for female stress or mixed urinary incontinence, with available English or French full texts. We excluded minislings (single insertion point). We allowed slings for recurrent stress or mixed urinary incontinence, 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.
Methods: We evaluated study quality using RoB, the Cochrane risk-of-bias tool for randomized controlled trials, and the Newcastle-Ottawa scale for observational studies. We used pooled relative risk with 95% confidence intervals to estimate the 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 articles (30 separate studies). For retropubic synthetic vs nonsynthetic slings, there was no difference in the number of objectively or subjectively continent patients. The rates of reoperation for stress urinary incontinence and overall were higher with nonautologous retropubic slings than with synthetic slings. Compared with autologous slings, retropubic synthetic slings were associated with higher subjective continence in populations with ≥25% recurrent stress urinary incontinence (relative risk, 1.27; 95% confidence interval, 1.12-1.43). There were no differences in continence between transobturator synthetic and nonsynthetic slings. Subjective satisfaction was better in the transobturator synthetic group than in the autologous sling group (relative risk, 1.42; 95% confidence interval, 1.03-1.94).
Conclusion: Synthetic and nonsynthetic slings have comparable objective and subjective success, with synthetic materials generally showing better operative outcomes and fewer complications.