A study of U.S. military personnel has found that troops exposed to bomb blasts in Iraq and Afghanistan showed signs of mental disability, even if they hadn’t been diagnosed with a brain injury.
The study, published Monday in the Journal of the American Medical Association Neurology, also found that the long-term effects of traumatic brain injuries are similar regardless of the mechanism that caused the injury.
Researchers looked at 178 personnel who were medically evacuated from Afghanistan or Iraq for various injuries, 82 of whom had been diagnosed with a concussion. Twenty-seven had been exposed to a blast but were not diagnosed with a concussion, and 69 had no blast exposure.
Those who suffered concussions from impacts and those whose injuries resulted from a combination of impact and blast showed nearly identical rates — 79 percent and 77 percent, respectively — of moderate to severe disability a year after their injuries. The finding suggests that the mechanism of injury isn’t something researchers and doctors “need to be too worked up about,” said Dr. David L. Brody, the study’s lead author and a neurologist at the Washington University School of Medicine in St Louis.
Brody’s team found that those who had been exposed to a blast but hadn’t been diagnosed with a concussion also showed some impairment a year after their injuries. Of this group, 59 percent showed signs of moderate to severe disability, as well as worse headaches and more severe post-traumatic stress disorder than patients who had no blast exposure.
“So we have to take blast exposure seriously, even if it doesn’t necessarily result in an overt concussive brain injury, as defined by a loss of consciousness, a gap in memory or confusion at the time of injury,” Brody said. “Blast exposure still may be associated with substantial symptoms — not as substantial as an actual concussive traumatic brain injury, but still substantial.”