Head trauma and neurodegeneration in veterans: an additional piece of the puzzle.
Neurology. 2014 Jul 22;83(4):298-9. Epub 2014 Jun 25
Please login to recommend the paper.
To make a comment you must login or register.
This study adds to the growing body of evidence pointing to traumatic brain injury (TBI) as a risk factor for Alzheimer’s disease and other dementias. The findings are generally consistent with a number of others. But because not all epidemiological studies have found an association between TBI and dementia, each additional study adds one more piece to the puzzle. In addition, it is timely given the Department of Defense and Veteran Affairs' focus on brain health, which includes increased support for research on the long-term outcomes of TBI.
The question is often asked whether results from military-related TBI studies are applicable to TBIs in civilian life. Clearly, many military-related TBIs may have different etiologies than civilian TBIs. For example, blast injuries are a common cause of military-related TBIs, but relatively less common among the civilian population. In addition, a higher proportion of TBIs incurred in the theatre of war may be more severe than those incurred during civilian life, and those with combat-related TBI may be at greater risk of having co-morbid PTSD. But even given these differences, the results from Barnes et al. are applicable to non-military TBIs because there are many similarities between military and civilian injuries. Since comprehensive longitudinal data on TBI is very limited, we need to learn from the data that is available regardless of whether it is based on head injuries incurred during military service or civilian life.
Despite the numerous studies that have examined the association between TBI and risk of dementia, many questions remain because no study to date has had all of the key data to comprehensively assess the association. The key information often spans decades and includes pre-TBI health and cognition, details of the TBI, acute and long-term TBI signs and symptoms, acute and long-term treatment, and genetics. To have all of this information in one dataset, we need to combine “silos” of data to create large repositories that include longitudinal military records spanning pre-deployment to acute or critical TBI care, military medical follow-up, and post-deployment care. Because decades often pass between trauma exposure and onset of dementia, detailed longitudinal follow-up is needed to accurately estimate TBI-associated risk of dementia. Such data would also allow us to better identify who among those with brain trauma is at elevated risk for dementia, and it would provide the opportunity to intervene prior to the onset of cognitive and functional decline.