Following a medical literature review to look for associations between traumatic brain injury (TBI) and long-term health problems, the Institute of Medicine (IOM) published a comprehensive report Dec. 4 titled Gulf War and Health: Volume 7. Long-term Consequences of Traumatic Brain Injury, available at: . This article follows up an earlier article in this issue of DCoE In Action which can be found .
The report makes recommendations that are consistent with earlier studies and reports by the Defense Health Board and the Army TBI Task Force.
The Department of Veterans Affairs (VA) commissioned the IOM report to evaluate the potential long-term consequences of TBI. The study readily identified the lack of literature on blast-related TBI and the long-term effects of TBI when blast injury is a contributing factor. IOM¿s review and the resulting report provide validation of Department of Defense (DoD) and VA initiatives that are already being carried out.
The five recommendations in the IOM report are listed below. Each recommendation is followed by an explanation of actions currently underway by DoD and the VA in these areas.
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"The committee recommends that the Department of Defense use the Brief Traumatic Brain Injury Screen and the Military Acute Concussion Evaluation for every soldier who has a history of blast exposure (even of low-intensity blast exposure)."
The Defense and Veterans Brain Injury Center (DVBIC) developed the Brief Traumatic Brain Injury Screen, which is a three-question screening tool. DoD adopted it with modifications for TBI screening in the Post-Deployment Health Assessment. The VA then adopted the screen with modifications for TBI screening when veterans enter the VA medical system through any portal. Modifications of this screening tool by both departments (the addition of a fourth question) included further description of current symptoms.
DVBIC also developed the Military Acute Concussion Evaluation, which has been deployed to war zones and is a key clinical tool recommended in the approved deployed clinical practice guidelines for management of mild TBI, which is also known as concussion. The evaluation is being distributed directly by DVBIC to both the Joint Theater Trauma System and to requesting providers through pre-deployment medical training platforms and packaged in deployed clinical practice guidelines.
- "The committee recommends that the Department of Defense and the Department of Veterans Affairs support prospective, longitudinal studies to confirm reports of long-term or latent effects of exposure to blasts. Those studies should examine the consequences of blast-induced neurotrauma, recovery timeline, and any factors that improve or worsen outcomes."
DVBIC is the executive agency for the congressionally mandated DoD 15-Year Longitudinal Study of TBI that is underway. The sample size includes at least 1,600 members of the military who have served in Iraq or Afghanistan. Approximately 1,200 have TBI, 300 were injured but did not have TBI, and the other 100 had no injuries. Recruitment will occur with three cohorts over a six-year period.
This will provide some ability to correlate outcomes and treatment received, which may contribute to further Clinical Practice Guideline development by enhancement of the evidence base. It will correlate TBI with co-morbid and long-term psychological conditions.
Collaborative efforts include: the Department of Veterans Affairs, Centers for Disease Control and Prevention, National Institutes of Health, DoD Personnel and Readiness, and the Uniformed Services University of the Health Sciences.
"The committee recommends that the Department of Defense and the Department of Veterans Affairs support research on animal models of blast-induced neurotrauma. Consideration should be given to developing models that would be relevant to human traumatic brain injury that encompass a more comprehensive experimental design. That could include studies that measure both behavior and pathology that might differ by traumatic brain injury severity. It would be important for the Department of Defense and the Department of Veterans Affairs to work with the research community and provide acute clinical data on human blast-induced neurotrauma to enable refinement of the animal models."
DoD animal model studies of the interaction between IED blasts and the neurologic system is being conducted through various programs. The Defense Advanced Research Projects Agency is conducting the PREVENT program (Preventing Violent Explosive Neurologic Trauma Program). PREVENT is evaluating the mechanism of blast brain injury through animal models and operational field correlations to which DVBIC is contributing. DVBIC has partnered with the Armed Forces Institute of Pathology to develop a TBI research center that will have the ability to facilitate animal model research and translational research with particular emphasis on the neurobiology of blast injury.
The Air Force Research Lab has partnered with the Defense and Veterans Brain Injury Center to conduct animal research to evaluate enriched environments in recovery from TBI.
Further animal testing is being conducted through funded Congressionally Directed Medical Research Program initiatives. Those include a major effort on TBI to solve some of the unanswered problems. Funded at more than $100 million, the program on TBI will yield clinical data on human blast-induced neurotrauma.
The Joint Improvised Explosive Device Defeat Organization has funded a number of programs. One that is particularly relevant is the ongoing program between Massachusetts Institute of Technology, DVBIC, Purdue and Duke Universities that is validating and developing human biomechanics research and blast simulation models.
This work has been expanded to the development of the porcine full head model for direct validation with controlled field blast exposure -- the accepted human surrogate animal model of choice.
"The committee recommends that the Department of Veterans Affairs include, in the development of the Traumatic Brain Injury Veterans Health Registry, other service members who could provide a valid comparison for the analysis of outcomes. Comparison groups should be made up of injured persons without traumatic brain injury or blast exposure, uninjured deployed veterans, and uninjured non-deployed but previously active-duty veterans. Those groups could be compared with persons who have received a diagnosis of traumatic brain injury and with those who have possible or probable traumatic brain injury. The three comparison groups should have samples large enough to provide reference rates of outcomes of interest. Furthermore, the registry needs to be representative of the traumatic brain injury population to be able to determine associations between such injury and various outcomes. There should be no exclusions on the basis of sex, race, geographic region, or rank."
DVBIC is the office of responsibility for DoD TBI Surveillance and Registry efforts. DBVIC is named as a collaborator on the VA Registry and is contributing to its development. The collaboration of DoD and VA on surveillance and registries is facilitating comparisons of populations and outcomes of individuals with the various levels of diagnostic certainty listed above. As recommended, comparison groups will include injured individuals who do not have TBI as well as uninjured individuals.
"In an effort to understand the long-term outcomes of traumatic brain injury, including consequences that might be related to blast, the committee recommends that all deployed military personnel undergo predeployment neurocognitive testing. The committee also recommends postdeployment neurocognitive testing of representative samples of military personnel (including those with traumatic brain injury, those with other non-TBI injuries, and uninjured service members without blast exposure)."
DVBIC was named as the office of responsibility for pre-deployment neurocognitive testing by the Office of the Secretary of Defense for Health Affairs.
Pre-deployment neurocognitive testing utilizing the Automated Neurocognitive Assessment Metric was initiated in 2008 in accordance with DoD policy. The U.S. Army operates as the central scheduling office for all services for this. 117,000 service members have been tested to date. Testing has been completed by way of embedded test sites or mobile testing units.
A head-to-head study of post-injury evaluations is underway, comparing five commercially available computerized neurocognitive test batteries. Results of this study will be utilized to ensure that the most sensitive and specific test is used for pre-deployment testing in the future. The study will have an 'in theater' and 'continental U.S.' arm.
Post-deployment studies have been completed or are underway. DVBIC completed a post-deployment Automated Neurocognitive Assessment Metric study at Ft Bragg on 956 returning service members - results indicated that, as a group, service members who sustained mild TBI while serving in Iraq and Afghanistan did not differ in the assessment compared to those without deployment mild TBI. Another study is pending results at Fort Campbell.
