title: Pain Duration and Resolution following Surgery: An Inception Cohort Study.
abstract: OBJECTIVE
  Preoperative determinants of pain duration following surgery are poorly understood. We identified preoperative predictors of prolonged pain after surgery in a mixed surgical cohort.
  
  
  METHODS
  We conducted a prospective longitudinal study of patients undergoing mastectomy, lumpectomy, thoracotomy, total knee replacement, or total hip replacement. We measured preoperative psychological distress and substance use, and then measured pain and opioid use after surgery until patients reported the cessation of both opioid consumption and pain. The primary endpoint was time to opioid cessation, and those results have been previously reported. Here, we report preoperative determinants of time to pain resolution following surgery in Cox proportional hazards regression.
  
  
  RESULTS
  Between January 2007 and April 2009, we enrolled 107 of 134 consecutively approached patients undergoing the aforementioned surgical procedures. In the final multivariate model, preoperative self-perceived risk of addiction predicted more prolonged pain. Unexpectedly, anxiety sensitivity predicted more rapid pain resolution after surgery. Each one-point increase (on a four point scale) of self-perceived risk of addiction was associated with a 38% (95% CI 3-61) reduction in the rate of pain resolution (P = 0.04). Furthermore, higher anxiety sensitivity was associated with an 89% (95% CI 23-190) increased rate of pain resolution (P = 0.004).
  
  
  CONCLUSIONS
  Greater preoperative self-perceived risk of addiction, and lower anxiety sensitivity predicted a slower rate of pain resolution following surgery. Each of these factors was a better predictor of pain duration than preoperative depressive symptoms, post-traumatic stress disorder symptoms, past substance use, fear of pain, gender, age, preoperative pain, or preoperative opioid use.
authors.affiliation: Departments of Anesthesiology, Perioperative, and Pain Medicine, Division of Pain Medicine, Stanford University, Palo Alto, California, USA.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Carroll
authors.affiliation: Departments of Anesthesiology, Perioperative, and Pain Medicine, Division of Pain Medicine, Stanford University, Palo Alto, California, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Hah
authors.affiliation: Departments of Anesthesiology, Perioperative, and Pain Medicine, Division of Pain Medicine, Stanford University, Palo Alto, California, USA.|Anesthesiology Service Department of Veterans Affairs, VA Palo Alto Health Care System, Palo Alto, California, USA.
authors.forename: Peter L
authors.initials: PL
authors.lastname: Barelka
authors.affiliation: Stanford Systems Neuroscience and Pain Lab (SNAPL), Stanford School of Medicine, Palo Alto, California, USA.
authors.forename: Charlie K M
authors.initials: CK
authors.lastname: Wang
authors.affiliation: Stanford Systems Neuroscience and Pain Lab (SNAPL), Stanford School of Medicine, Palo Alto, California, USA.
authors.forename: Bing M
authors.initials: BM
authors.lastname: Wang
authors.affiliation: Stanford Systems Neuroscience and Pain Lab (SNAPL), Stanford School of Medicine, Palo Alto, California, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gillespie
authors.affiliation: Stanford Systems Neuroscience and Pain Lab (SNAPL), Stanford School of Medicine, Palo Alto, California, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: McCue
authors.affiliation: Departments of Anesthesiology, Perioperative, and Pain Medicine, Division of Pain Medicine, Stanford University, Palo Alto, California, USA.
authors.forename: Jarred W
authors.initials: JW
authors.lastname: Younger
authors.affiliation: Departments of Psychiatry & Behavioral Sciences, Veterans Affairs and Stanford University, Palo Alto, California, USA.
authors.forename: Jodie
authors.initials: J
authors.lastname: Trafton
authors.affiliation: Departments of Psychiatry & Behavioral Sciences, Veterans Affairs and Stanford University, Palo Alto, California, USA.
authors.forename: Keith
authors.initials: K
authors.lastname: Humphreys
authors.affiliation: Orthopaedic Surgery, Stanford University, Palo Alto, California, USA.
authors.forename: Stuart B
authors.initials: SB
authors.lastname: Goodman
authors.affiliation: Surgery, Stanford University, Palo Alto, California, USA.
authors.forename: Fredrick M
authors.initials: FM
authors.lastname: Dirbas
authors.affiliation: Departments of Anesthesiology, Perioperative, and Pain Medicine, Division of Pain Medicine, Stanford University, Palo Alto, California, USA.
authors.forename: Sean C
authors.initials: SC
authors.lastname: Mackey
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage*; D002140:California / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000187:drug effects* / Q000379:methods*; D010149:Postoperative Pain / Q000188:drug therapy* / Q000453:epidemiology* / Q000523:psychology; D015995:Prevalence; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D000701:Analgesics, Opioid
keywords: Acute Pain; Addiction; Postoperative Pain