In the military, a concussion can temporarily keep a soldier out of a war zone. When that concussion is followed by another concussion, the effects can be devastating. Concussion is one of the most common injuries impacting today’s military. Among servicemen and women with exposure to combat in Iraq and Afghanistan, 15 to 20 percent experience traumatic brain injury; of those, 85 percent are mild concussions, the result of exposure to blasts.1
Although likely under reported, repeat concussion (or “cumulative concussion”) seems to occur among a smaller segment of the military population. One study found 113 reports of repeat concussion among 14,653 servicemen and women who served in Operation Iraqi Freedom from 2004 to 2008. Among those, 20 percent suffered the second trauma within two weeks of the first; another 87 percent experienced the second trauma within three months of the first concussion.2 “We are seeing more of this in the military because the head becomes more vulnerable with the type of combat occurring in the world today,” says Roger Cady, MD, associate executive chairman of the National Headache Foundation and founder and director of the Headache Care Center, Inc. in Springfield, Mo.
Despite the smaller population, the risks are more significant for individuals who suffer repeat concussions than for those who suffer a singular concussion. Research indicates that recovery is slower, neurological damage is prolonged and susceptibility to additional brain injuries increases after repeat concussions.3 To avoid complications, military servicemen and women must make every effort to avoid concussions and take time to heal after trauma occurs.
From Concussion to Headache
A single concussion can trigger post-concussion headache in the form of tension-type headache, episodic migraine, chronic daily headache or a combination. Those who already had headaches or a family history of headaches prior to trauma are more likely to experience some form of post-concussion headache.
For soldiers who already experience headache, repeat concussions can take an episodic condition and turn it into a chronic, daily problem, says Alan G. Finkel, MD, FAAN, FAHS, a contractor for the Henry Jackson Foundation/Defense and Veterans Brain Injury Center at Fort Bragg, N.C. and co-founder of the Carolina Headache Institute. “Repeat concussions appear to make it more likely that these headaches will become intractable,” Dr. Finkel says.
The Risk for Permanent Damage
In addition to extending a headache condition, repeat concussion can also turn other concussion side effects (e.g., memory and concentration deficits, sleep disorders and balance difficulties) into more serious and longer-lasting concerns.
Perhaps even more alarming, repeat concussion can lead to permanent brain damage, including the potential for a progressive degenerative disease called chronic traumatic encephalopathy (CTE). Although CTE was once known as a boxer’s condition and is receiving media attention for its effects on foot- ball players, it can affect anyone with multiple head traumas. The condition, which leads to brain atrophy and nerve cell damage, can cause progressive memory and cognition deficits, long-term personality changes, suicidal behavior and dementia.4
Repeat concussion can also trigger second-impact syndrome (SIS), a rare complication in which the brain swells rapidly, leading to death or severe disability. SIS can develop if a second concussion occurs before symptoms of an earlier one have subsided.
Unfortunately, researchers don’t yet know how many concussions are too many and which concussion might lead to permanent damage. The threshold may vary from person to person, depending on differences in genetics, the environment and the dynamics of the injury, according to Dr. Cady. Uncertainty aside, physicians do agree that prevention and early treatment can help reduce concussion risks.
The Importance of Downtime
Helmets and protective gear can help reduce the risk of head trauma to an extent. Dr. Finkel suggests it would also be helpful for the military to train soldiers “to avoid situations where head injuries are more prevalent.” But ultimately, Dr. Finkel and Dr. Cady agree that, given the way wars are fought today, there is really no effective way to prevent a concussion.
“The military provides sophisticated protective gear and training to help soldiers in combat prevent injury,” Dr. Cady says. “However, the magnitude of an assault like that of an improvised explosive device is beyond the limits of this protection.”
To optimize recovery following a head injury, early diagnosis and treatment of post-traumatic headache is essential. Further, military servicemen and women must be offered an environment in which the brain has time to recover from the assault, Dr. Cady says.
“When adequate time and proper environment for recovery are not provided, this can lead to more disabling headaches and other symptoms associated with concussion,” Dr. Cady says. “Also, when the brain is concussed, reaction time and cognition may be affected, which increases the risk of re-injury.”
To fully recuperate, military personnel may need to take time off from active duty. While this may seem initially disruptive, it can lead to a healthier life in the long-term and the maintenance of a functional deployed status. With proper conservative care and a gradual return to regular activities, most brains recover from injury, even after repeat concussion, Dr. Cady says.
Unfortunately, with the risk of a disrupted tour of duty, soldiers may be reluctant to seek treatment. But military leaders are increasingly urging servicemen and women to seek treatment instead of downplaying their symptoms. In an effort to reduce the side effects of traumatic brain injury, the U.S. Army developed new guidelines that require troops caught within 165 feet of a blast to be removed from the battlefield for at least 24 hours and examined for evidence of a concussion.5 Soldiers sustaining three concussions in one deployment are required to undergo a more detailed evaluation before being cleared to return to combat.
If implemented successfully, the latter effort combined with adequate downtime could save many soldiers from carrying home the insidious effects of concussion.
References:
- Rigg and Mooney. “Concussions and the Military: Issues Specific to Service Members.” PM&R. 2011;3:S380-S386.
- MacGregor et al. “Repeated Concussion Among U.S. Military Personnel During Operation Iraqi Freedom.” Journal of Rehabilitation Research & Development. 2011;48(10):1269-1277.
- Defense and Veterans Brain Injury Center. “Cumulative Concussions.” www.dvbic.org/cumulative-concussions
- Stern et al. “Long-term Consequences of Repetitive Brain Trauma: Chronic Traumatic Encephalopathy.” PM&R. 2011;3:S460-S467.
- Zoroya. “More Troops’ Concussions Diagnosed Under New Rules.” USA Today. October 28, 2010.
