title: Impact of perioperative pain intensity, pain qualities, and opioid use on chronic pain after surgery: a prospective cohort study.
abstract: OBJECTIVE
  A better understanding of the pathogenesis of chronic postsurgical pain is needed in order to develop effective prevention and treatment interventions. The objective of this study was to evaluate the incidence and risk factors for chronic postsurgical pain in women undergoing gynecologic surgery.
  
  
  METHODS
  Pain characteristics, opioid consumption, and psychologic factors were captured before and 6 months after surgery. Analyses included univariate statistics, relative risks (RRs) and 95% confidence intervals (95% CIs), and modified Poisson regression for binary data.
  
  
  RESULTS
  Pain and pain interference 6 months after surgery was reported by 14% (n = 60/433) and 12% (n = 54/433), respectively. Chronic postsurgical pain was reported by 23% (n = 39/172) with preoperative pelvic pain, 17% (n = 9/54) with preoperative remote pain, and 5.1% (n = 10/197) with no preoperative pain. Preoperative state anxiety (RR = 1.8; 95% CI, 1.1-2.8), preoperative pain (pelvic RR = 3.7; 95% CI, 1.9-7.2; remote RR = 3.0; 95% CI, 1.3-6.9), and moderate/severe in-hospital pain (RR = 3.0; 95% CI, 1.0-9.4) independently predicted chronic postsurgical pain. The same 3 factors predicted pain-interference at 6 months. Participants describing preoperative pelvic pain as "miserable" and "shooting" were 2.8 (range, 1.3-6.4) and 2.1 (range, 1.1-4.0) times more likely to report chronic postsurgical pain, respectively. Women taking preoperative opioids were 2.0 (range, 1.2-3.3) times more likely to report chronic postsurgical pain than those not taking opioids. Women with preoperative pelvic pain who took preoperative opioids were 30% (RR = 1.3; 95% CI, 0.8-1.9) more likely to report chronic postsurgical pain than those with preoperative pelvic pain not taking opioids.
  
  
  CONCLUSIONS
  Preoperative pain, state anxiety, pain quality descriptors, opioid consumption, and early postoperative pain may be important predictors of chronic postsurgical pain, which require further investigation.
authors.affiliation: Department of Anesthesiology & Perioperative Medicine, Queen's University, Kingston, Ontario, Canada. ev5@queensu.ca
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: VanDenKerkhof
authors.forename: Wilma M
authors.initials: WM
authors.lastname: Hopman
authors.forename: David H
authors.initials: DH
authors.lastname: Goldstein
authors.forename: Rosemary A
authors.initials: RA
authors.lastname: Wilson
authors.forename: Tanveer E
authors.initials: TE
authors.lastname: Towheed
authors.forename: Miu
authors.initials: M
authors.lastname: Lam
authors.forename: Margaret B
authors.initials: MB
authors.lastname: Harrison
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Reitsma
authors.forename: Shawna L
authors.initials: SL
authors.lastname: Johnston
authors.forename: James D
authors.initials: JD
authors.lastname: Medd
authors.forename: Ian
authors.initials: I
authors.lastname: Gilron
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D001007:Anxiety / Q000150:complications; D016009:Chi-Square Distribution; D059350:Chronic Pain / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D013509:Gynecologic Surgical Procedures / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D009864:Ontario; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology; D017699:Pelvic Pain / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology; D057234:Preoperative Period; D011446:Prospective Studies; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013997:Time Factors
chemical_list: D000701:Analgesics, Opioid