An episode of major depressive illness is fairly common after a mild traumatic brain injury, especially among patients with signs of damage visible on a CT scan, investigators report.

“Early identification of patients at risk for major depressive episode could facilitate referral for treatment before symptoms progress,” Dr. Harvey S. Levin at the Baylor College of Medicine in Houston and colleagues point out in the Archives of General Psychiatry.

To identify factors associated with increased risk, Levin’s group followed 129 patients who suffered a mild brain injury. The subjects underwent CT scanning and were assessed for depression starting one week after injury - though patients were excluded if they previously had a major psychiatric disorder.

Within three months, 15 subjects (over 11 percent) had experienced a major depressive episode.

The chances of developing depression increased by 5 percent for each year of age, the researchers found. Also, the risk of a major depressive episode was more than 7 times higher among patients with an abnormal CT result.

The likelihood of depression occurring is increased during the first three months and throughout the first year after a mild brain injury, Levin’s group concludes, but this could be reduced by paying attention to those who are at high risk based on their age and CT scan results.

They note that it is more feasible to identify at-risk patients at the outset than to follow-up all cases of mild head trauma.

SOURCE: Archives of General Psychiatry, May 2005.