Staged meta-analysis of high- versus low-quality randomised trials testing triclosan coated sutures on surgical site infection after abdominal surgery

Abstract

Introduction: Conflicting meta-analyses have been published comparing the effectiveness of triclosan coated sutures. This creates confusion amongst clinical teams, guideline committees, and policymakers for how to interpret these findings. We aimed to understand how study quality influences the results of meta-analysis on the use of triclosan sutures in patients undergoing abdominal surgery and impact on surgical site infection.

Methods: A systematic review was performed to identify randomised controlled trials comparing triclosan coated versus uncoated sutures for closure of the fascial layer during clean-contaminated, contaminated, and dirty abdominal surgery, published up to April 2024. We performed a sequence of pre-specified meta-analyses, to understand the effects of including low quality studies and explore potential sources of bias. We then performed a simulated meta-analysis to determine the effect of new randomised trials being added to the high quality evidence base.

Results: From 634 studies, our final meta-analysis included 15 studies (n=11,475 patients), of which six were high quality and nine low quality studies. The high quality studies included 8,937 patients from 12 countries. The low quality included 2,538 from 11 countries. The high quality studies showed no significant difference in rates of surgical site infections (OR: 0.88, 95% CI: 0.71 - 1.09). When the low quality studies were included, there was a significant shift in the effect to show a benefit with triclosan-coated sutures (OR: 0.67, 95% CI: 0.54 - 0.83). Meta-regression identified that increasing study quality was associated with smaller effect size towards non-significance. Simulation showed that new studies will only marginally shift these results and only if strongly positive.

Conclusion: This study highlights potential uncertainty around the clinical effectiveness of triclosan-coated sutures, particularly when assessed through high-quality randomised trials. While lower-quality studies suggest benefit, these effects were not replicated in more robust evidence, although geographical uncertainty and practices in different settings around the world may explain some differences. However, some caution may be needed in value-based health systems, especially if prices fluctuate, and such investment may be best suited to high-risk or expensive cases where marginal gains are important. As clinical practice continues to evolve, further well-conducted, high-quality trials (including both randomised and efficient platform observational cohort studies) may help resolve this uncertainty.