Traumatic brain injuries have become the signature wound of the wars in Afghanistan and Iraq and troops who sustain them face a daunting array of potential medical consequences later on, says a report on the issue commissioned by the U.S. Department of Veterans Affairs.
The report from the Institute of Medicine - a body that advises the U.S. government on science, medicine and health - said military personnel who sustain severe or even moderate brain injuries may go on to develop Alzheimer's-like dementia or symptoms similar to Parkinson's, a neurodegenerative disease.
They face a higher risk of developing seizure disorders and psychoses, problems with social interactions and difficulty holding down a job. Troops who sustain even mild brain injuries are more likely to develop post-traumatic stress disorder (PTSD). And all are at a higher risk of experiencing aggressive behaviour, depression and memory problems.
The report urged the U.S. government to ramp up research in the area, saying there isn't enough evidence in the medical literature - especially as relates to mild brain injuries - to determine what today's troops face and how best to help them recover from or cope with the health problems they may develop.
"The more severe the injury, the more likely there are to be bad long-term outcomes," Dr. George Rutherford, chair of the panel that produced the report, acknowledged in an interview from Washington.
But Rutherford said that brain injuries don't have to be severe or involve penetration of the skull to set up a soldier for significant health consequences.
"If you have a traumatic brain injury - especially if it's moderate or severe - you have some chance of developing a disease down the line that you would not have developed otherwise," said Rutherford, an epidemiologist at the University of California, San Francisco.
"For mild brain injuries, which is a much bigger group of injuries and it has a much broader scope, what we can say is for those kinds of injuries that there's a probable association between having one of those - especially with loss of consciousness - and having depression, having aggressive behaviour ... or having persistent post-concussive symptoms."
"Like memory loss, like headaches, like dizziness."
The panel read 1,900 studies on brain injuries looking for evidence of what troops who suffer brain injuries might face. But most of the studies relate to injuries suffered in car crashes and sports. The report says the injury picture could look different for troops who may also develop post-traumatic stress disorder from experiences in combat and that more research is needed.
The report noted that as of January 2008, more than 5,500 U.S. military personnel had suffered traumatic brain injury in Iraq and Afghanistan as a result of the widespread use against them of improvised explosive devices, or IEDs.
A similar Canadian figure for troops deployed to Afghanistan is not available, Maj. Andre Berdais, a senior public affairs officer with the Canadian Forces Health Services Group, said via email.
Berdais said that kind of data is not tracked by the Department of National Defence, as it isn't "essential in supporting our primary responsibility of patient care."
But New Democrat MP Dawn Black, who has pressed the issue as a member of the House of Commons' defence committee, said these injuries are a growing problem among Canadian troops.
"The rates are going up," Black said from Ottawa. "Intuitively we know. But we also know from anecdotal evidence from people in the field."
Black said the problem was put on her radar by soldiers and their families. "I've met with some of them and seen it. I've met with some of the families and seen it."
The force of an explosion can induce what is essentially a concussion in the brain, sending it ricocheting around within the confines of the skull.
The damage caused by even a mild brain injury can take six months to heal, said Dr. Donald Stuss, a brain expert and vice-president of research at the Rotman Research Institute of Toronto's Baycrest Centre for Geriatric Care.
Injury can be done to different parts of the brain, triggering a variety of problems. But Stuss stressed that after-effects - or whether there are any long-term problems - will vary from person to person.
"So you may end up having somebody with a head injury who recovers perfectly and then afterwards has tinnitus (ringing in the ears) and dizziness from inner ear problems.... You may have some who end up with long-term memory problems," he said.
Stuss said the key is to identify people with the problem and start treating them quickly.
The Forces' Berdais said troops who have been exposed to explosions and may have suffered blast-induced injuries are screened for traumatic brain injury. Those found to be suffering from it are removed from active duty while they are symptomatic to prevent the risk of a repeat injury that could compound the insult on the brain.
And he said the Canadian Forces' new physical rehabilitation program is in the process of developing policies and procedures for troops who continue to show symptoms of traumatic brain injury despite having received care.
Psychologist Gerrit Groeneweg, executive director of Calgary's Brain Injury Rehabilitation Centre, said people suffering lingering problems from traumatic brain injuries can benefit from being taught coping techniques - strategies for improving memory and training to help overcome problems with attention.
But finding out how to best treat traumatic brain injuries among troops remains a challenge, said Dr. Greg Passey, a psychiatrist with Vancouver Coastal Health Services who spent 22 years in the Canadian Forces and who now specializes in treating PTSD.
"We don't have a really clear understanding of what the potential long-term effects are," Passey said.
"Because some of our soldiers have been exposed - they're getting blown up more than one time. And although they don't have significant outward physical injuries, you can certainly develop things like post-traumatic stress disorder or other types of psychological or psychiatric disorders."
