• Posted April 23, 2024

Repeat Blasts Can Damage Soldiers' Brains, Study Confirms

Soldiers can suffer brain injury if they are repeatedly exposed to explosive blasts, a new study shows.

Further, the more frequently a soldier is exposed to explosions, the greater their risk for brain injury, researchers reported April 22 in the Proceedings of the National Academy of Sciences.

Based on this, researchers intend to develop a diagnostic test to detect blast brain injury in military personnel.

"The availability of a reliable diagnostic test could improve operators' quality of life by ensuring that they receive timely, targeted medical care for symptoms related to repeated blast brain injury,"said co-senior researcher Yelena Bodien, an investigator with Massachusetts General Hospital's Center for Neurotechnology and Neurorecovery.

For this study, researchers followed 30 active-duty U.S. Special Operations Forces personnel. On average, the soldiers were 37 and had 17 years of military service.

They all had extensive combat exposure and had high levels of blast exposure and blows to the head. Half had endured more blunt impacts to the head than they could recall.

The soldiers underwent a series of brain scans focused on a region of the frontal lobe called the rostral anterior cingulate cortex, which is known to be a widely connected brain network hub that modulates cognition and emotion, researchers said.

The scans showed an association between cumulative blast exposure and changes to this brain region, particularly with blast waves that penetrate the openings in the skull behind the eyes.

Blasts appeared to alter brain structure and affect brain function, results show. Explosions also seemed to affect the brain's immune response.

Higher exposure to blasts also was associated with lower health-related quality of life, based on questionnaires the soldiers filled out.

However, the study did not link blast exposure to lower cognitive performance or increased post-traumatic stress disorder (PTSD) symptoms in the personnel.

No specific blood-based biomarkers for brain injury were detected during the study, researchers said.

However, the personnel did have higher-than-expected levels of tau in their blood. Tau is a protein strongly linked to the development of Alzheimer's disease.

As a result, tau levels might be useful in developing a portable diagnostic test for brain injury resulting from blast exposure, researchers said.

"Ultimately, the goal of this research is to enhance the combat readiness, career longevity and quality of life of the United States' most elite forces,"said lead researcher Dr. Brain Edlow, co-director of Mass General Neuroscience.

"These are American heroes who answered the call to serve after the terrorist attacks of September 11, 2001, and fought the most dangerous missions of the Global War on Terror for two decades,"Edlow said in a hospital news release. "They deserve the best medical care, and while more research is needed, our results suggest that a diagnostic test for repeated blast brain injury is within reach."

More information

The U.S. Department of Veterans Affairs has more on blast-related brain injuries.

SOURCE: Massachusetts General Hospital, news release, April 22, 2024