The incidence of major depression among 559 people with traumatic brain injury was nearly eight times greater than would be expected in the general population, the researchers report in the May 19th issue of the JAMA/Journal of the American Medical Association.
While major depression during the first year was associated with a poorer quality of life and ability to function, less than half of the people who were found to have major depression received any treatment during the first year, Dr. Jesse R. Fann from the University of Washington School of Medicine in Seattle and one the study's principal investigators told Reuters Health.
An estimated three million Americans are living with a traumatic brain injury -- defined as a sudden violent blow to the head or penetrating wound that affects normal brain function. The most common cause is automobile accidents. Traumatic brain injury is also a signature injury among wounded soldiers, the investigators note.
Noting that treatment for traumatic brain injury normally focuses on the injury and its effect on a person's ability to think clearly, Fann and colleagues wanted to clarify how often severe depression develops after a major traumatic brain injury and if it affects recovery.
Of the 1,080 brain injury patients admitted to one trauma center in Seattle between June 2001 and March 2005, 559 agreed to participate in the study and were followed for 12 months. Study participants were mostly men injured in automobile accidents.
The researchers report that more than half of the participants (about 53 percent) were diagnosed with major depression at some point in the first year after their brain injury - a rate that is about 8 times greater than would be expected.
Not counting those that were depressed at the time they were injured, 233 of the remaining 471 participants (49 percent) experienced new major depression.
For a variety of reasons, the investigators say the rates of major depression after traumatic brain injury are probably conservative and underestimate the problem.
Major depression was associated with increased anxiety, poorer self-reported health and lower quality of life. The investigators urge making mental health services part of the normal care of patients with a traumatic brain injury.
In the current study, only 44 percent of those with major depression received antidepressants or counseling.
Because major depression after traumatic brain injury is an invisible disorder within an often invisible injury, aggressive efforts are needed to educate doctors, promote detection and treat patients where warranted, they conclude.
Fann cautions against generalizing these study findings to traumatic brain injury suffered by soldiers on the battle field.
These were civilian injuries; the findings, however, are consistent with military studies showing that head injuries, especially when there has been a loss on consciousness, do have a significantly higher rate of depression.