The roles of pain catastrophizing and anxiety in the prediction of postoperative pain intensity: a prospective study

OBJECTIVES: This study was a prospective investigation of the extent to which psychologic variables could be predictive of postoperative pain. Study aims were: 1) to evaluate whether an assessment of pre-operative distress factors could predict the intensity of postoperative pain; and 2) to characterize the unique pattern in which anxiety and pain catastrophizing scores relate to postoperative pain. METHODS: The Pain Catastrophizing Scale and the State-Trait Anxiety Inventory were administered to 38 patients scheduled for elective abdominal surgery. The questionnaires were completed on the day of admission, a day before the operation. On day 1 and day 2 following the operation, perception of pain intensity at the surgical wound was assessed by visual analog scale. RESULTS: The Pain Catastrophizing Scale and State-Trait Anxiety Inventory scores were significantly correlated with the postoperative pain scores. A linear regression analysis showed that Pain Catastrophizing Scale predicted the level of postoperative pain intensity even after controlling for state anxiety and that trait anxiety was not a significant predictor. In addition, analysis of the unique pattern of each predictor related to postoperative pain intensity indicated a linear curve for the Pain Catastrophizing Scale and curvilinear curve for the state anxiety. DISCUSSION: The results are discussed in light of appraisal and coping theories. It is suggested that a simple assessment of preoperative catastrophizing tendency and anxiety scores may assist medical teams in postoperative pain management.