Background
Chronic post-surgical pain is a common complication of surgery. The role of psychological risk factors like depression and anxiety is substantially understudied in cardiac surgery. This study sought to identify perioperative factors associated with chronic pain at 3, 6, and 12 months after cardiac surgery. We hypothesize that baseline psychological vulnerabilities have a negative influence on chronic post-surgical pain.
Methods
We prospectively collected demographic, psychological, and perioperative factors in a cohort of 1059 patients undergoing cardiac surgery at the Toronto General Hospital between 2012-2020. Patients were followed and completed chronic pain questionnaires at 3, 6, and 12 months after surgery.
Results
We included 767 patients who completed at least one follow-up questionnaire. The incidence of postsurgical pain (> 0 out of 10) at 3, 6, and 12 months after surgery was 191/663 (29%), 118/625 (19%), and 89/605 (15%), respectively. Notably, among patients reporting any pain, the incidence of pain compatible with a neuropathic phenotype increased from 56/166 (34%) at 3 months, to 38/97 (39%) at 6 months and 43/67 (64%) at 12 months. Factors associated with postsurgical pain scores at 3 months include female sex, pre-existing chronic pain, previous cardiac surgery, preoperative depression, baseline pain catastrophizing scores, and moderate-to-severe acute pain (≥4 out of 10) within 5 postoperative days.
Conclusion
Nearly one in three patients undergoing cardiac surgery reported pain at 3 months follow-up, with ~15% reporting persistent pain at 1 year. Female sex, pre-existing chronic pain, and baseline depression were associated with postsurgical pain scores across all three time periods.