Antidepressants are known to provide effective pain relief for various chronic pain conditions; however, the jury is still out on their use in treating patients who suffer from acute or chronic pain following surgery. A first-of-its-kind literature review published in the September issue of Anesthesiology, the official medical journal of the American Society of Anesthesiologists (ASA), suggests that although most studies report positive outcomes, there is insufficient evidence to support the clinical use of antidepressants for postoperative pain.
Many surgical patients experience chronic postoperative pain many months or even years after their original surgery. "There is a need for improved treatment options in the management of postoperative pain, and antidepressants could potentially be a valuable addition," said Ian Gilron, MD, lead author and professor and director of clinical pain research at Queen’s University in Ontario, Canada. "Our review of the literature showed several positive trial results, but we also found important research limitations in the studies, indicating a need for higher quality, more definitive trials on antidepressant use for postsurgical pain."
In the study, researchers performed a systematic review of all published clinical trials on antidepressants and postoperative pain. Fifteen studies on acute (985 patients) and three studies on chronic (565 patients) postoperative pain were included. Extracted data from the studies included pain at rest and with movement, pain relief, adverse effects, and other outcomes such as mood, sleep, and physical function.
Nearly half of the studies suggested that antidepressants resulted in significant treatment benefits over placebo. However, the researchers identified several important limitations in many of the trials. Those limitations included too few patients, inadequate safety evaluation and procedure specificity, variable dosing, and limited pain assessment.
The review said future clinical trials should optimize dosing, timing, and duration of antidepressant treatment, trial size, patient selection, safety evaluation and reporting, procedure specificity, and assessment of movement-evoked pain relevant to postop functional recovery. Trials should better define the risk-benefit ratio of antidepressants in postop pain management because these drugs can be linked to serious adverse effects in the time around surgery, the authors note.