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.