Long-term Outcomes of Biologic versus Synthetic Mesh for Parastomal Hernia Repair: Post-Hoc Analysis of a Multicenter Randomized Clinical Trial.

Abstract

<h4>Objective</h4>Here we aimed to examine the outcomes of parastomal hernia repair after 5 years in patients undergoing concomitant open retromuscular ventral hernia repair randomized to biologic or synthetic mesh as part of a clinical trial (NCT#02451176).<h4>Summary of background data</h4>Previously, we reported that parastomal hernia recurrence rates at 2 years were similar between treatment arms with no difference in mesh-related complications. Long-term data on parastomal hernia repair outcomes is otherwise sparse.<h4>Methods</h4>We conducted a post-hoc analysis of the aforementioned multicenter clinical trial (December 2012-April 2019) specifically looking at patients undergoing concomitant parastomal hernia repair during open retromuscular ventral hernia repair. Exploratory outcomes included rates of parastomal hernia recurrence, mesh-related complications, and reoperation. Cox proportional hazards models were constructed to estimate hazard ratios for parastomal hernia recurrence associated with mesh type, adjusting for potential confounders including age, sex, race, BMI, smoking status, mesh defect ratio, and mesh size. Subgroup analysis of mesh configuration (retromuscular Sugarbaker vs keyhole) was also performed.<h4>Results</h4>Of 108 patients, 88 (81.5%) achieved five-year follow-up (median 5.9 y). The parastomal hernia recurrence rate was 33.6% (37.5% biologic versus 29.4% synthetic mesh), of which 15 (14%) underwent reoperation (9 biologic, 6 synthetic). Following adjustment for confounders, synthetic mesh demonstrated a 45% reduction in recurrence risk (HR=0.65, 95% CI: 0.44-0.96, P=0.028). No new mesh-related complications occurred beyond two years. Subgroup analysis of retromuscular mesh configuration showed no difference in parastomal recurrence rate (25.9% vs. 36.3%; P=0.358) or recurrence-free survival (log rank P=0.33).<h4>Conclusions</h4>Synthetic mesh was associated with significantly lower long-term parastomal hernia recurrence rates compared to biologic mesh at 5 years with no difference in mesh-related complications.