Authors: Charles W. Hoge M.D.
When a warrior experiences a moderate or severe TBI on the Iraq or
Afghanistan battlefields, this almost always results in rapid air transportation to one of the large military hospitals in Germany or the United States for
neurosurgical, neurological, and rehabilitation services. Some of these warriors experience severe disability and require long-term treatment.
In contrast, when a warrior experiences a concussion/mTBI on the
battlefield, which may involve being briefly knocked out, or getting their
"bell rung" from a blast or other injury, this almost never results in evacuation from the combat theater. Concussions/mTBIs are very common in
the military (as in nonmilitary settings) from sports injuries, motor vehicle
accidents, hand-to-hand combatives training, and combat. Although concussions can occasionally lead to long-term health effects-such as headaches, irritability, sleep disturbance, memory problems, or fatigue-most
warriors who experience concussions recover quickly. Concussions/mTBIs
are clearly not the same as moderate and severe TBIs, but in the minds of
many warriors, family members, the public, and even medical professionals, they have become the same condition, requiring an equivalent level
of concern.
After every war, warriors have experienced high rates of physical,
cognitive, emotional, or behavioral health concerns, including memory
and concentration problems, anger, headaches, sleep disturbance, high
blood pressure, rapid heart rate, pain, fatigue, dizziness, and other difficulties. These problems are associated with neurological, endocrine,
cardiovascular, and immune system changes likely related to physiological effects of extreme stress on the body, extended sleep deprivation,
environmental exposures, and other factors.
The reactions that warriors experience after coming back from war have
been given different labels through the generations, including "Nostalgia"
(Napoleonic Wars); "Da Costa Syndrome," "Irritable Heart" (U.S. Civil War);
"Effort Syndrome," "Shell Shock" (World War I); "Battle Fatigue" (World
War II); "Acute Combat Stress Reaction" (Korean War); "Agent Orange Syndrome," "Substance Abuse," "PTSD" (Vietnam); and "Gulf War Syndrome"
(Gulf War 1). Some of these problems have been associated with serious
environmental exposures (e.g., Agent Orange, Gulf War Syndrome).
After every war, the same mistakes are made. Rather than recognize
that going to war can change the body's physiology in a number of ways and identify the best treatments for the full range of health problems that warriors experience, postwar symptoms are attributed to causes that are highly
influenced by prevailing politics. After every war, veterans are told that
their war-related symptoms are "stress-related" or "psychological" (which
understandably infuriates them), and the medical community becomes
embroiled in divisive debates as to whether the causes of war-related symptoms are predominantly "psychological" or "physical" (or environmental)
in origin. While medical professionals and policy-makers get caught up in
debating the definition and nature of the problems (influenced by poorquality scientific data and "turf" battles regarding allocation of resources),
veterans feel that their problems are not taken seriously. Health professionals and policy-makers responsible for establishing initiatives to address
the problems are well intentioned, but often become overly dependent on
the advice of "experts," and myopic to any scientific evidence that doesn't
support their positions. Ironically, the need to be perceived as expediently
doing everything possible in the interest of veterans leads to the rapid
implementation of interventions that are not necessarily beneficial, and
may even prove harmful.
For the current OIF and OEF wars, the same problems have emerged.
Intense debate is now going on in the medical community (and involving
veterans organizations, politicians, and reporters), regarding whether
or not certain war-related reactions-such as cognitive problems, rage,
sleep disturbance, fatigue, headaches, and other symptoms-are best
explained by a "psychological" cause (PTSD) or a "physical" cause
(mTBI). Both have been labeled the "signature injuries" of these wars.
There has been intense speculation, generated by a large gap in scientific
knowledge, that exposure to primary pressure waves from explosions in
Iraq and Afghanistan has caused "silent" mTBI injuries in hundreds of
thousands of otherwise uninjured warriors that may predispose them to
long-term problems. Advocates for the mTBI position, typically experts
in neurology, rehabilitative medicine, or neuropsychology, have suggested that blast-related mTBI represents a new form of brain injury, and
have even proposed that PTSD may be caused by the mTBIs themselves
(ignoring the context in which these injuries occur).
Advocates for the PTSD position, who are often mental health professionals, frequently cite articles that our team at the Walter Reed Army
Institute of Research had published in the New England Journal of Medicine in 2008 and 2009. These showed that concentration and memory
problems, anger, sleep disturbance, fatigue, dizziness, balance problems,
headaches, and other difficulties reported by soldiers returning from
Iraq were much more likely to be associated with PTSD than with concussion/mTBI, and that concussion/mTBI alone was only very weakly
associated with any of these problems. Several other studies have also
confirmed our findings. Advocates for both positions, however, have misunderstood the most important evidence from these research studies,
having to do with the optimal treatment of interrelated health concerns
through collaborative care approaches.
So what is the truth about concussion/mTBI and its relationship
to PTSD? What are the most important things for you to understand
about any problem you may be experiencing, and treatments that are
available? The remainder of this chapter summarizes the answers from a
number of different studies.
CONCUSSION/mTBI: THE FACTS
Concussion/mTBI is not the same thing as moderate and severe TBI.
Moderate and severe TBI are very serious medical conditions that
require comprehensive treatment by neurologists, neurosurgeons, rehabilitation medicine professionals, mental health professionals, and other
specialists working together. Moderate and severe TBIs are usually seen
clearly on brain scans and result in health problems that can be detected
on physical, neurological, and neuropsychological examinations. There
have been remarkable advances in the treatment of moderate and severe
TBI, and even after severe injuries, there is hope for recovery to high
levels of functioning. However, recovery can be slow, and the warrior
may not be able to get back to full functioning even after long-term treatment. This is very different than concussion/mTBI, and only concussion/mTBI is addressed in this book.
The term concussion is preferred over the term mTBI (mild traumatic
brain injury) to clearly distinguish this from moderate and severe TBIs.
Concussion/mTBI is defined as a blow or jolt to the head that briefly
knocks you out (loss of consciousness); causes a temporary gap in your
memory; or makes you confused, disoriented, or "see stars" (change in
consciousness). This is also known as getting your "bell rung." Most warriors who experience a concussion during hand-to-hand combatives training, during sports, as a result of a motor vehicle accident, or after blast
explosions on the battlefield are only temporarily confused or disoriented.
If they experience memory gaps or are knocked out, this usually lasts for a
few seconds or minutes. When brain scans are performed, they are usually
normal. Injury to some nerves in the brain may be able to be seen with
newer brain-imaging technologies, but these are very subtle, difficult to
detect, and these technologies are not useful yet in directing treatment.
Concussions can result in headaches, irritability, dizziness, balance
difficulties, fatigue, sleep disturbance, ringing in the ears, blurred vision,
cognitive problems (including concentration or memory difficulties),
as well as other symptoms. These almost always clear up soon after the
injury, but in some warriors may persist for a longer period; there is poor
understanding of why they persist in some individuals. The newer brainimaging methods often show healing of damaged areas, but they don't
always match with resolution of symptoms. When symptoms persist after
concussion in combat, they are indistinguishable from symptoms warriors experience as a result of other injuries, or physiological effects of
working in the war environment.
If you experienced one or more concussions during deployment or
during your military service, and you're experiencing any of the above
symptoms now, they may or may not be related. These types of symptoms
are common after combat. Their presence likely does not mean that something is persistently wrong with your brain, as implied by the term brain
injury. While they might be related to concussions that you had during
your service, this is only one of many possible causes.
The best time to make a diagnosis of concussion/mTBI is at the time
of injury, and it becomes progressively more difficult to diagnose the more time has passed. The treatment prescribed at the time of injury
is to rest until symptoms resolve, which generally occurs in a few hours
to a few days. Once weeks or months have passed since the injury, there
is no way for a doctor to accurately determine the exact cause of your
symptoms, no matter how well trained they are. There is no blood test,
brain scan, or neuropsychological test that can determine with certainty
whether physical, cognitive, or behavioral symptoms and reactions that
persist after combat-such as headaches, concentration/memory problems, anger, or sleep problems-are due to physiological changes from
combat, the physiological effects of PTSD, the effects of exposure to
chemicals or environmental factors, lingering effects of concussions or
other injuries, the result of chronic sleep deprivation in combat, or various other potential causes. Also, knowing the likely cause doesn't help
very much with treatment, since treatment for these problems is exactly
the same whether or not concussion is responsible. There are a variety
of treatments that your doctor can prescribe to help with specific symptoms, such as persistent headaches.
Full recovery is expected even if you've had more than one concussion
during deployment. The brain has a remarkable ability to heal itself through
growing new connections between nerves, a process called "plasticity" that
goes on continuously in the brain. Areas of the brain that are damaged can
be replaced or reconnected through growth of other neurons. Things that
help with healing include good sleep and avoidance of alcohol or drugs
(both of which will be addressed in chapter 4). The brain is a living organ
that can show remarkable healing capability even after very serious injuries,
and certainly after concussions or mTBIs from any cause.
Although concerns about the health effects ofblastwaves are legitimate
and are being actively researched, most injuries that warriors experience
from explosions in Iraq and Afghanistan are due to fragments, shrapnel,
or being thrown against something. It's very unlikely to have effects on the
brain from the primary pressure wave of an explosion without other serious injuries. Fragment dispersion in explosions usually extends out much
farther than the pressure wave, particularly if the explosion goes off in an
open space. If an explosion penetrates a vehicle or building, the primary pressure wave can get amplified inside the space, causing greater damage,
but this is usually accompanied by very severe injuries that are not "silent."
This is an area that requires further research, but it's not beneficial for
you to worry excessively about possible long-term brain effects because
you were injured from or close to one or more explosions while deployed.
Worry itself has been tied to physiological changes in the body that can
contribute to symptoms or hinder healing. Even if there were some lingering effects from the blasts you were exposed to that the medical community hasn't fully identified, there's no reason to think that the brain can't
heal itself as effectively after blast-related concussions as after concussions
from sports, motor vehicle accidents, or combatives training.
Concussion/mTBI is not the same thing as PTSD, and having an
either/or perspective isn't helpful. Concussion is the injury event itself.
PTSD, as explained in the last chapter, refers to a specific set of reactions
or symptoms after trauma (that may or may not have included physical injury) persisting for at least one month, and usually much longer.
Although persistent symptoms after concussion can overlap with those of
PTSD, they can also overlap with hundreds of other medical conditions,
and it's not helpful to focus only on these two conditions. If you experienced a concussion during deployment, you may be at higher risk for
PTSD because of the context in which the concussion occurred. If you
were knocked out or temporarily disoriented from a blast on the battlefield, this was a very close call on your life, and you may also have had
buddies who were injured from the same explosions. It's understandable
to experience PTSD symptoms after these types of experiences.