Bomb blasts cause an estimated 78 percent of combat injuries from Operations Enduring and Iraqi Freedom and New Dawn (OEF/OIF/OND). A group of 333 Veterans who returned from these operations participated in a VA Boston study that evaluated their cognitive functions, psychiatric diagnoses and history of military and non-military brain injury.
Boston VA Healthcare System doctors Regina McGlinchey and William Milberg led the Translational Research Center for TBI and Stress Disorders (TRACTS) study that investigated the relationship between close proximity to detonated blast munitions and cognitive functioning in OEF/OIF/OND Veterans.
The results, published in the Journal of the International Neuropsychological Society, showed that Veterans who were close to a blast during service (10 meters or less) performed more poorly on a test of memory than did Veterans who were never that close to a blast.
Lead author, Dr. Laura Grande, said these injuries are not always accompanied by symptoms of concussion, such as a loss of consciousness, a memory gap for the blast, or feelings of confusion in the immediate aftermath of the blast.
“We found the impairment in memory could not be explained by the number of symptomatic concussions an individual sustained over his/her lifetime and was, instead, driven largely by close exposure to a blast.”
Study lead, Dr. Regina McGlinchey, said the participants were assigned to a close-range blast exposure group or a non-close-range blast exposure group, depending on whether they were exposed to at least one blast within 10 meters.
“We compared their performance on tests of memory, verbal fluency and complex attention. We took into account factors that can influence cognitive functioning, including age, education, whether someone had been diagnosed with PTSD or a substance abuse disorder, and/or experienced sleep problems or suffered from chronic pain. We found that the close-range blast exposure group showed poorer performance on memory functioning, as well as significantly higher rates of clinical impairment when compared to the non-close-range blast exposure group,” McGlinchey said.
To read more about this study, , go to the Journal of the International Neuropsychological Society’s website.
About the author: Kathryn Bienfang is a public affairs officer for VA New England Health Care System’s research program.