title: Psychological risk factors for chronic post-surgical pain after inguinal hernia repair surgery: a prospective cohort study.
abstract: A significant proportion of patients experience chronic post-surgical pain (CPSP) following inguinal hernia surgery. Psychological models are useful in predicting acute pain after surgery, and in predicting the transition from acute to chronic pain in non-surgical contexts. This is a prospective cohort study to investigate psychological (cognitive and emotional) risk factors for CPSP after inguinal hernia surgery. Participants were asked to complete questionnaires before surgery and 1 week and 4 months after surgery. Data collected before surgery and 1 week after surgery were used to predict pain at 4 months. Psychological risk factors assessed included anxiety, depression, fear-avoidance, activity avoidance, catastrophizing, worry about the operation, activity expectations, perceived pain control and optimism. The study included 135 participants; follow-up questionnaires were returned by 119 (88.1%) and 115 (85.2%) participants at 1 week and 4 months after surgery respectively. The incidence of CPSP (pain at 4 months) was 39.5%. After controlling for age, body mass index and surgical variables (e.g. anaesthetic, type of surgery and mesh type used), lower pre-operative optimism was an independent risk factor for CPSP at 4 months; lower pre-operative optimism and lower perceived control over pain at 1 week after surgery predicted higher pain intensity at 4 months. No emotional variables were independently predictive of CPSP. Further research should target these cognitive variables in pre-operative psychological preparation for surgery.
authors.affiliation: School of Life and Health Sciences, Aston University, UK. r.k.powell@aston.ac.uk
authors.forename: R
authors.initials: R
authors.lastname: Powell
authors.forename: M
authors.initials: M
authors.lastname: Johnston
authors.forename: W C
authors.initials: WC
authors.lastname: Smith
authors.forename: P M
authors.initials: PM
authors.lastname: King
authors.forename: W A
authors.initials: WA
authors.lastname: Chambers
authors.forename: Z
authors.initials: Z
authors.lastname: Krukowski
authors.forename: L
authors.initials: L
authors.lastname: McKee
authors.forename: J
authors.initials: J
authors.lastname: Bruce
mesh_terms: D000328:Adult; D000368:Aged; D001519:Behavior; D059350:Chronic Pain / Q000453:epidemiology* / Q000523:psychology*; D003071:Cognition; D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D013505:Digestive System Surgical Procedures / Q000009:adverse effects*; D004644:Emotions; D005260:Female; D006552:Hernia, Inguinal / Q000601:surgery*; D006801:Humans; D007813:Laparotomy; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000453:epidemiology* / Q000523:psychology*; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D012606:Scotland; D011795:Surveys and Questionnaires; D016896:Treatment Outcome