Insights into rates and impact of mTBI among military personnel in Iraq/Afghanistan

As the last U.S. troops return home from Iraq, new research lends timely insights into the rates and impact of mild traumatic brain injury (mTBI) among military personnel serving in Iraq/Afghanistan, according to a topical issue of The Journal of Head Trauma Rehabilitation (JHTR), the official journal of the Brain Injury Association of America. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

The January topical issue of JHTR includes a study suggesting that British troops deployed to Iraq or Afghanistan have lower rates of mTBI than their American counterparts, and that psychological factors present before deployment to combat are a major contributor to lasting symptoms in military personnel with mTBI. Other studies report on the surprising relationship between mTBI and other traumatic injuries, the high burden of mTBI on family caregivers, and a promising approach to treatment.

Lower Rates of mTBI in British than American Troops
Roberto J. Rona, FFPH, and colleagues of King's College London analyzed rates of mTBI and in a large sample (over 4,600) of U.K. troops deployed to Iraq or Afghanistan. mTBI—injuries with short-term loss of consciousness or changes in mental status, sometimes followed by lasting physical, cognitive, and behavioral symptoms—has emerged as an important concern in the U.S. and U.K. military. It has been described as the "signature injury" of the wars in Iraq and Afghanistan.

The study showed a 4.4 percent rate of mTBI among U.K. troops overall, increasing to 9.5 percent among those with a combat role. Blast injuries and falls were the most common causes of mTBI, followed by vehicle crashes.

The prevalence of mTBI in British military personnel appears lower than in previous studies of U.S. troops, which reported rates ranging from 12 percent to over 22 percent. In a second paper, Rona and colleagues report that the difference in mTBI rates is partly related to differences in length of deployment—which is longer for U.S. troops. However, deployment times could not completely account for the difference in mTBI rates.

The study also found that psychological factors—especially previous mental health symptoms and alcohol misuse—were important risk factors for continued symptoms of mTBI. Posttraumatic stress disorder (PTSD) was another possible risk factor. Rona and colleagues findings partly conflict with a controversial 2008 study in The New England Journal of Medicine, which reported that mTBI was unrelated to most physical health outcomes or symptoms, after accounting for PTSD and depression.

Symptoms of More Severe TBI; High Impact on Caregivers; a Promising Treatment Approach
Another study, led by Louis M. French, PsyD, of Walter Reed Army Medical Center, looked at the relationship between mTBI and other physical injuries. Surprisingly, the researchers found that symptoms related to mTBI were actually lower in veterans with more severe bodily injuries. It may be that mTBI symptoms go unnoticed, or develop later, in military personnel with other types of severe injuries.

Joan M. Griffin, PhD, of the Minneapolis VA Medical Center and colleagues looked at the experiences of family caregivers of U.S. veterans with mTBI and other injuries. They found that, for veterans who need help with basic daily functions, a tremendous amount of responsibility falls to the spouse or parents. These caregivers "may need additional resources to meet the long-term needs of their injured family member," the researchers write.

Gregory K. Wolf, PsyD, of the James A. Haley VA Medical Center, Tampa, Fla., report encouraging results with a treatment approach called prolonged exposure therapy for veterans affected by mTBI and PTSD. Including education, breathing exercise, and real-world practice, prolonged exposure therapy is one of the primary proven treatment approaches for PTSD.

"Though the sample was small, this is one of the first studies indicating that prolonged exposure therapy can be safely and effectively implemented with veterans who had had a mild or moderate TBI and consequent cognitive impairment," comments John D. Corrigan, PhD, ABPP, Professor of Physical Medicine and Rehabilitation at The Ohio State University and Editor-in-Chief of JHTR.

Dr Corrigan adds, "We hope the papers included in this topical issue will serve to stimulate awareness and appropriate clinical management of returning service members who may be living with the aftereffects of traumatic brain injury."