BETHESDA, MD — With all of the attention given traumatic brain injury in recent years, it can be easy to forget that this is still a nascent area of medical science. It took six years of fighting in Afghanistan and Iraq for the military leaders to realize the impact TBI — especially the cumulative effects of multiple mild TBI — was having on servicemembers.
“This really is a new field,” explained Kathy Helmick, MS, RN, deputy director of the Defense Centers of Excellence (DCoE), at the 4th Annual Trauma Spectrum Conference held on the campuses of NIH. “We’re still exploring this realm in the medical literature, and there’s still a paucity of research.”
Her message to the conference was that, while physicians know far less about the mechanics of TBI than they would like, military researchers have been given the order to move as fast as safely possible with translating research into practice in order to help injured troops and veterans.
Less Than a Decade of Research
There have been 220,430 diagnosed cases of TBI in servicemembers since 2000. In 2000, prior to the current wars, there were 11,000 cases of TBI in the military, even without battlefield conditions.
The vast majority — between 60% and 80% — have been mild TBI (mTBI) — the type scientists understand least.
Research into TBIs did not take off until the 1990s, and most of that decade was spent studying severe and penetrating brain injuries, Helmick said. Little was known about the long-term effects of concussion.
“At the beginning of the war, the thinking in the military was that it happened, and there was nothing to be done about it,” Helmick said. If a servicemember was involved in a blast-related incident, he or she had to come forward and request a medical evaluation. Servicemembers were unlikely to do that if, as Helmick said, “they ‘just saw stars’ for a moment.”
It was not until 2007 that the evidence of cumulative cerebral effects from mTBIs began to come to light. It was not until 2009 that line commanders were approached with evidence of how those effects were impacting a servicemember’s functional abilities.
“This was what spoke to line leadership — when they see that the impact of concussion can have an impact on the soldier’s [effectiveness],” Helmick said. “It spoke to the essence of how a concussion can impact a war fighter, and that it was something that needed to be addressed.”
With evidence that mTBI could result in poor marksmanship, slower reaction time and decreased concentration, the model of sending soldiers back into combat without being evaluated began to be replaced with something different.
Changing the Diagnosis Paradigm
|Airmen test their memory skills during a portion of the Automated Neuropsychological Assessment Metrics test Nov. 5, 2009, at Moody Air Force Base, Ga. An Army team visited Moody AFB to help conduct a mass ANAM testing for more than 800 Airmen. The test, which establishes a baseline for an individual’s brain activity, is mandatory prior to deploying. (U.S. Air Force photo/Airman 1st Class Joshua Green)|
In June 2010, DoD issued a directive-type memorandum that ordered all servicemembers involved in a blast-related incident or who were within 50 meters of a blast to automatically be evaluated for TBI.
“We moved from a paradigm of, ‘Hi, I’ve got a headache, [so] I need to be seen,’ to ‘If you’re near a blast, you need to go see medical,’” Helmick said. “This was really important because it signified a change in how we did business: mandatory event-driven, rather than symptom-based reporting.”
Prior to this directive, servicemembers were sometimes evaluated as much as five weeks after the event. By then, symptoms of TBI could be even harder to diagnose.
“They were medically evacuated to Landstuhl, and then line commanders were wondering if they were ever coming back to finish their tour,” Helmick explained. “Now it’s a line effort, not a medical effort. Our goal is to get you diagnosed, treated and back to your unit ASAP. Evacuations to Landstuhl have dropped sharply.”
Not only does immediate treatment help curtail long-term effects, it also helps with future diagnoses involving the patient. If that patient shows up to a VA hospital, years after the blast-incident, complaining of some of the many symptoms shared by PTSD, TBI, depression and substance-abuse disorder, TBI can be ruled out, at least from that specific incident.
The effectiveness of the system is hampered, however, by communication issues between DoD and VA. At the conference, one VA provider told Helmick that she had patients who came in talking about a battlefield “TBI clinic” where TBI was or wasn’t ruled out after a blast incident. However, data from that clinic was nowhere in the patient’s record.
“The data is starting to all come together,” Helmick said. “The sources are there, and we’re trying to push it through these different IT systems so clinicians can have them. We haven’t forgotten about VA.”Mild TBI Remains Little Understood and Hard to Diagnose Cont.
The Search for Concussion Markers
Even diagnosing mTBI is not as clear-cut an issue as people imagine. While there are very solid markers for diagnosing moderate, severe and penetrating TBI, there are no objective markers for concussion. Currently, clinicians are required to talk with their patients, gather information and make a diagnostic judgment based on that conversation but using no objective scientific data.
“There’s a dire necessity to find an objective marker for concussion,” Helmick said. “We have been very much challenged and prompted by Congress to find this objective marker beyond the clinical judgment.”
There are a number of promising research avenues, including papillary response and visual tracking; biomarkers in serum, saliva and skin; diffusion tensor imaging; and electrophysiological parameters.
“This is an area of research in which a lot of money has been spent, and we feel that there’s a lot of promising work,” Helmick said. “But we don’t believe it will be one single thing, one magic bullet. It will be some combination of tests.”
Military physicians also are working on teasing apart the symptoms of commonly comorbid conditions like PTSD, TBI, chronic pain, depression, and substance-use disorder. “The longer we went on in the war, the more we realized that comorbidities were an issue,” Helmick said. “People weren’t coming back clean, with TBI as an only issue.”
To address this, DCoE put out a co-occurring conditions toolkit giving clinical guidance on how to treat patients with two or more of these diagnoses.
“It’s in its infancy. This is Version One,” Helmick said. “It will have to evolve through time. But in the grand scheme, this was an achievement.”
How to Screen for mTBI
As the science into finding objective markers continues, military physicians are searching for ways to better identify returning servicemembers who have suffered a TBI.
One way of doing this is to get a better baseline of how the servicemember was before being deployed. Currently, all servicemembers prior to deployment are required to take part in automated neuropsychological assessment metrics (ANAM) testing — a computer-based tool designed to test speed and accuracy of attention, memory and thinking ability.
If a servicemember is injured, their ANAM score can be compared to their current score, and this can help determine fitness. “It’s only one piece of data, but it’s the only objective data that we have right now, and it can help inform a return to duty decision,” Helmick said.
“Unfortunately,” she said, “Congress had mandated a different [method] — test before, get a baseline, then test everybody after. And if there are any differences, after 12 to 15 months of war, figure out why it’s different. Of the hundreds of things it could be, find out what.”
Congress considers it the largest possible safety net, ensuring that no one suffering from employment experiences is left undiagnosed, which is the same goal of the military, Helmick said.
Helmick suggested, however, that this giant safety net might not be as effective as the military’s injury-based screening paradigm and will create far more work. GAO, she said, conducted an audit and found that population-based screening using neurocognitive testing was not effective for diagnosing concussion.
“We have to figure out where we can meet on this,” she said.
One area where Congress and military leaders are in agreement is in getting new treatments into the hands of clinicians as soon as possible.
“There has been a paradigm shift in research,” Helmick said. “We’re looking for the 80% solution.” The 80% solution refers to the idea that it is better to launch a treatment that research has shown to be somewhat effective or effective in some patients, and to do so quickly enough to benefit the patients that need treatment now, than to wait for a 99% effective treatment that takes much longer to research and field.
DoD is conducting numerous studies into neuroprotection drugs, neuroplasticity after injury and cutting-edge methods of treatment and rehabilitation. For example, there are currently three major DoD studies to see if hyperbaric oxygen treatment is effective post-TBI.
“Some of this is snake oil, and it will eventually come off the radar screen,” Helmick said. “But if it’s safe and effective, leadership wants us piloting it in military cohorts.”