Risk factors for recurrence and surgical site infection after abdominal wall hernia repair: a systematic review and meta analysis

Background Surgical site infection (SSI) and hernia recurrence are among the most common and impactful complications following abdominal wall hernia repair. Identifying patient-related risk factors is essential for improving outcomes and guiding perioperative management. Methods A systematic review and meta-analysis were conducted in accordance with PRISMA 2020 and AMSTAR 2 guidelines. PubMed, Embase, Scopus, CNKI,Wanfang, and VIP were searched up to September 20,2025. Eligible studies included randomized controlled trials, cohort, and case-control studies that reported associations between patient-related variables and SSI or recurrence after hernia repair. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models. Beyond I 2 , the 95% prediction interval (PI) was utilized as the primary metric to evaluate the absolute dispersion of true effects. Risk of bias was assessed using the Newcastle–Ottawa Scale (NOS). Results A total of 11 studies involving 97,428 patients were included. No significant associations were observed for female sex (OR: 1.05, 95% CI: 0.77–1.42, P = 0.77; 95% PI: 0.48–2.29), obesity (OR: 1.15, 95% CI: 0.78–1.68, P = 0.48; 95% PI: 0.37–3.55), COPD (OR: 0.95, 95% CI: 0.47–1.92, P = 0.88; 95% PI: 0.14–6.25), or immunosuppressive therapy (OR 0.90, 95% CI: 0.38–2.14, P = 0.81). Although diabetes mellitus reached nominal statistical significance (OR: 1.46, 95% CI: 1.01–2.11, P = 0.04), its wide 95% PI (0.55–3.90) suggested considerable inconsistency across cohorts. Similarly, higher ASA classification (>3 vs. <2; OR: 1.63, 95% CI: 0.96–2.78, P = 0.07; 95% PI: 0.47–5.69) was not a consistent predictor. Data on recurrence were fragmented and unsuitable for robust pooled analysis, although individual studies suggested that risk factors for recurrence may differ from those for SSI. Conclusions Contrary to common clinical assumptions, traditional host-related risk factors such as gender, obesity, and diabetes do not consistently predict adverse outcomes after abdominal wall hernia repair when clinical heterogeneity is rigorously accounted for. The wide 95% PIs observed for most factors underscore substantial clinical variance across surgical settings. These findings highlight the limitations of relying on isolated comorbidities for risk assessment and advocate for the development of integrated, individualized risk prediction models. Systematic Review Registration https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD420261278753 , identifier CRD420261278753.