Veterans exposed to explosions who do not report symptoms of traumatic brain injury (TBI) may still have damage to the brain’s white matter comparable to veterans with TBI, according to researchers at Duke Medicine and the U.S. Department of Veterans Affairs.
The findings, published in the Journal of Head Trauma Rehabilitation on March 3, 2014, suggest that a lack of clear TBI symptoms following an explosion may not accurately reflect the extent of brain injury.
Veterans of recent military conflicts in Iraq and Afghanistan often have a history of exposure to explosive forces from bombs, grenades and other devices, although relatively little is known about whether this injures the brain. However, evidence is building – particularly among professional athletes – that subconcussive events have an effect on the brain.
“Similar to sports injuries, people near an explosion assume that if they don’t have clear symptoms – losing consciousness, blurred vision, headaches – they haven’t had injury to the brain,” said senior author Rajendra A. Morey, M.D., associate professor of psychiatry and behavioral sciences at Duke University School of Medicine and a psychiatrist at the Durham Veterans Affairs Medical Center. “Our findings are important because they’re showing that even if you don’t have symptoms, there may still be damage.”
Researchers in the Mid-Atlantic Mental Illness Research, Education and Clinical Center at the W.G. (Bill) Hefner Veterans Affairs Medical Center in Salisbury, N.C., evaluated 45 U.S. veterans who volunteered to participate in the study. The veterans, who served since September 2001, were split into three groups: veterans with a history of blast exposure with symptoms of TBI; veterans with a history of blast exposure without symptoms of TBI; and veterans without blast exposure. The study focused on veterans with primary blast exposure, or blast exposure without external injuries, and did not include those with brain injury from direct hits to the head.