Abstract
INTRODUCTION: Incisional hernia (IH) is the main long-term complication after midline laparotomy and has significant clinical and economic effects. Although multiple risk factors for IH formation have been proposed, their ranking and clinical relevance have not been clearly established. This meta-analysis aimed to estimate the prevalence of IH and rank the associated risk factors, considering both their statistical significance and their clinical impact. METHODS: This meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (CRD420251107739). Observational (cohort and cross-sectional) studies evaluating patients undergoing midline laparotomy with follow-up for IH were included. Clinical trials and studies involving a laparoscopic approach were excluded. The global prevalence of IH was calculated, and random effects models were used to identify risk factors associated with the occurrence of IH, whose associations are reported as hazard ratios (HRs) and 95% confidence intervals. RESULTS: Twenty studies (n = 790,800 patients) were included, among whom the overall prevalence of IH was 10.1% (95% CI: 7%-15%). Only 10 studies analyzed relevant risk factors. The factors with the greatest clinical impact were reoperation during hospitalization (HR = 4.09) and surgical site infection (HR = 2.96). Other significant factors included emergency surgery, colon surgery, stoma creation, diabetes, and liver disease. Factors such as sex, obesity, or hypertension were not significantly associated with IH formation. CONCLUSIONS: Perioperative factors are key determinants of the occurrence of IH. The identification of such factors would allow prioritization of preventive interventions, such as the application of prophylactic meshes, especially in high-risk patients. Standardized prospective studies are needed to validate these findings.