Smaller Inguinal Hernias are Independent Risk Factors for Developing Chronic Postoperative Inguinal Pain (CPIP): A Registry-based Multivariable Analysis of 57, 999 Patients.

Abstract

Impact of inguinal hernia defect size as stratified by the European Hernia Society (EHS) classification I to III on the rate of chronic postoperative inguinal pain (CPIP). CPIP is the most important complication after inguinal hernia repair. The impact of hernia defect size according to the EHS classification on CPIP is unknown. In total, 57,999 male patients from the Herniamed registry undergoing primary unilateral inguinal hernia repair including a 1-year follow-up were selected between September 1, 2009 and November 30, 2016. Using multivariable analysis, the impact of EHS inguinal hernia classification (EHS I vs EHS II vs EHS III and/or scrotal) on developing CPIP was investigated. Multivariable analysis revealed for smaller inguinal hernias a significant higher rate of pain at rest [EHS I vs EHS II: odds ratio, OR = 1.350 (1.180-1.543), P < 0.001; EHS I vs EHS III and/or scrotal: OR = 1.839 (1.504-2.249), P < 0.001; EHS II vs EHS III and/or scrotal: OR = 1.363 (1.125-1.650), P = 0.002], pain on exertion [EHS I vs EHS II: OR = 1.342 (1.223-1.473), P < 0.001; EHS I vs EHS III and/or scrotal: OR = 2.002 (1.727-2.321), P < 0.001; EHS II vs EHS III and/or scrotal: OR = 1.492 (1.296; 1.717), P < 0.001], and pain requiring treatment [EHS I vs EHS II: OR = 1.594 (1.357-1.874), P < 0.001; EHS I vs EHS III and/or scrotal: OR = 2.254 (1.774-2.865), P < 0.001; EHS II vs EHS III and/or scrotal: OR = 1.414 (1.121-1.783), P = 0.003] at 1-year follow-up. Younger patients (<55 y) revealed higher rates of pain at rest, pain on exertion, and pain requiring treatment (each P < 0.001) with a significantly trend toward higher rates of pain in smaller hernias. Smaller inguinal hernias have been identified as an independent patient-related risk factor for developing CPIP.