Assessment of the European Hernia Society Classification of Ventral Hernias and Clinical Outcomes.

Background: Ventral hernias are a common but heterogeneous disease. Communication among key stakeholders (eg, patients, clinicians, administrators, payers, and researchers) can be augmented by a widely utilized classification system. The European Hernia Society (EHS) developed an expert-opinion-based hernia classification system organized by hernia type (primary versus incisional) and size. We sought to assess what components of the EHS ventral hernia classification system were correlated to real-world clinical outcomes. Methods: This was a multicenter cohort study. All hospitals contributing to the database were affiliated with 1 of 6 academic institutions. All adult patients who underwent ventral hernia repair over a 4-year period were included. The primary endpoint was adverse events defined as any major (deep or organ space) surgical site infection (SSI), abdominal reoperation, or hernia recurrence. Utilizing a multivariable Cox regression, factors associated with adverse events were identified. Accuracy was assessed using Harrell's C concordance statistic. Results: Of the 2385 patients who underwent repair of ventral hernias (primary n = 810, 34.0% and incisional n = 1575, 66%), with a median follow-up of 11.1 months, 27.5% suffered adverse events including major SSIs (5.7%), hernia recurrences (12.1%), and abdominal reoperations (9.7%). In the overall cohort and the primary ventral hernia subgroup, all hernia-specific variables were associated with adverse events. American Society of Anesthesiologist score, low albumin, and prior SSI were associated with adverse events in the overall cohort and primary ventral hernia subgroup while surgical approach was associated with adverse events in the overall cohort and incisional ventral hernia subgroup. On multivariable Cox regression analyses, incisional ventral hernia and larger hernia width were independently associated with adverse events. Conclusion: Hernia size and type (primary versus incisional) from the EHS ventral hernia classification system were associated with clinical outcomes. Additional factors, including patient and operative factors, also impact outcomes. Our model allows key stakeholders to communicate more clearly regarding the challenges and outcomes of various patients with diverse ventral hernias.