Incidence and predictors of chronic pain after inguinal hernia surgery: a systematic review and meta-analysis

The mesh is currently the preferred treatment option for hernia repair surgery. Chronic postoperative inguinal pain (CPIP), lasting more than 3 months after surgery, is a complication that significantly impacts patients' quality of life. Currently, there is a lack of evidence-based information describing the incidence and independent predictive factors of chronic pain, posing a serious challenge in clinical practice for devising personalized prevention strategies. Hence, we conducted this systematic review and meta-analysis to investigate the incidence and predictive factors, aiming to provide a reference for developing plans to prevent chronic pain.

We conducted a systematic search of PubMed, Cochrane, Embase, and Web of Science, with the retrieval cutoff date set at December 17, 2022. The included studies underwent assessment using the NOS scale, and subgroup analysis for the incidence was carried out based on different regions.

Ultimately, 18 studies were included, involving 29,466 patients. Meta-analysis showed that the pooled incidence of chronic pain was 17.01% (95%CI 12.78% ~ 21.71%). The incidence was 18.65% (95%CI 13.59% ~ 24.29%) in Europe, 14.70% (95%CI 7.87% ~ 23.17%) in Asia, and 6.04%(95%CI 4.62 ~ 7.64) in North America. Furthermore, We also found that the risk factors for CPIP are younger age [OR = 2.261 (95%CI 1.126 ~ 4.549)], presence of other postoperative complications [OR = 1.849 (95%CI 1.034 ~ 3.305)], hernial sac defect < 3 cm [OR = 1.370 (95%CI 1.012 ~ 1.853)], being female [OR = 1.885 (95%CI 1.024 ~ 3.472)], postoperative pain [OR = 1.553 (95%CI 1.276 ~ 1.889)], preoperative pain [OR = 2.321 (95%CI 1.354 ~ 3.979)], and having a history of ipsilateral inguinal hernia repair [OR = 2.706 (95% CI 1.445 ~ 5.069)].

The incidence of persistent pain following hernia repair surgery is high in current clinical practice, a concern that should not be overlooked. Stratified assessment tools need to be established for patients experiencing early chronic pain, and personalized follow-up strategies and preventive interventions should be developed for those with potentially high risks. These measures aim to enhance the quality of life for patients after hernia repair.