Study investigates effects of antidepressant treatment in pain catastrophizing patients

A select population of patients having surgery experience what is called pain catastrophizing - an irrational thought process that leads a patient to perceive pain as worse than it actually is. Antidepressant medications reduce negative mood and might change this way of thinking, but according to a study published in the April edition of Anesthesiology, the official medical journal of the American Society of Anesthesiologists® (ASA®), that may not be the case, at least for acute pain.

"Pain catastrophizing patients report more pain right after surgery, but whether or not targeted therapy can reduce pain among these patients had not been investigated," said Troels H. Lunn, M.D., Ph.D., lead author, Department of Anaesthesiology and Intensive Care, University of Copenhagen, Denmark. "Our study was the first to investigate the effects of SSRIs (selective serotonin reuptake inhibitors, one class of antidepressants) on pain immediately after surgery."

Dr. Lunn and his colleagues studied 120 patients with pain catastrophizing disorder who were scheduled for total-knee replacement surgery. The patients were given either the escitalopram or a placebo daily from the day of surgery to the sixth day after surgery, in addition to a pain medication regime. Twenty-four hours after surgery, patients were asked to report their level of pain while walking. The researchers found that the antidepressant treatment did not reduce pain 24 hours after the procedure. They did, however, find that overall pain scores days two through six after surgery were reduced with the antidepressant treatment. According to Dr. Lunn, the findings suggest that initiating antidepressant treatment earlier may reduce pain immediately after surgery.

"This topic calls for future studies on the effect of this and other classes of antidepressants on postsurgical pain, and our study can serve as a basis for such research," said Dr. Lunn.

An accompanying editorial commented favorably on the study:

"Although the primary outcome of the study by Lunn et al. was negative, the approach was an important next step in the anesthesiologist's role in defining care in the surgical home," said Chad M. Brummett, M.D. and Daniel J. Clauw, M.D, professors of anesthesiology at the University of Michigan. "The authors have made major contributions to our understanding of acute and chronic postsurgical pain and are poised to continue to advance clinical care…we look forward to additional work from this prominent research team."

Source: American Society of Anesthesiologists