The Canadian government is launching a multimillion dollar national initiative to study the impact of concussion on the developing brain in response to growing concerns about children's safety in hockey and other sports.
Health Minister Rona Ambrose announced Monday in Calgary that $4.3-million in federal grants will go to 19 new and ongoing concussion research projects. Many are aimed at solving unanswered questions about how mild traumatic brain injuries, commonly known as concussions, affect children and youth.
Funded by the Canadian Institutes of Health Research (CIHR), the research projects will receive an additional $3.2-million from other sources, including Defence Research and Development Canada, Ontario Neurotrauma Foundation and Hotchkiss Brain Institute, for a total investment of $7.5-million.
"Whether it's [a result of] a hockey concussion, a senior's fall or violence in the home, injuries take a huge emotional toll on families and communities," Ambrose said in a statement. "Our government is committed to promoting injury prevention by supporting research aimed at improving the health of Canadians who are facing challenges due to traumatic brain injury."
Until recently, concussion research was largely focused on adults, said Dr. Nick Reed, a specialist in acquired brain injury at a new concussion research centre launched earlier this month at Holland Bloorview Kids Rehabilitation Hospital in Toronto. "It really is amazing to us that we don't know more about what's going in the pediatric brain," Reed said. "I think it's partially because [researchers] haven't looked before in a focused, collaborative way."
Reed is working with CIHR grant recipient Dr. Michelle Keightley at Holland Bloorview to study new ways to diagnose and treat concussion in children and youth. Other major CIHR grant recipients include Dr. Carolyn Emery and Dr. Karen Barlow, both at the University of Calgary, and Dr. Roger Zemek at Children's Hospital of Eastern Ontario.
The push to better understand how concussions affect kids coincides with a dramatic decline in minor league hockey enrolment across Canada. According to a report commissioned by Hockey Canada, record numbers of parents are keeping their children out of hockey, largely because of safety concerns. In the survey, conducted during the 2011-12 season, three out of 10 parents said they had a player who had suffered a concussion.
Children account for nearly 38 per cent of emergency visits for concussions, according to the Government of Ontario.
Mild traumatic brain injuries are difficult to diagnose in children, however, since researchers do not fully understand how they affect a child's cognitive and physical functions, Reed said.
He and Keightley hope to bridge the knowledge gaps by conducting tests of agility, strength and physical and cognitive functions in healthy young athletes preseason, he said. In the event of a concussion, the researchers will use these measures as the player's baseline to detect changes and track signs of recovery after a blow to the head.
In addition, Keightley and Reed are studying whether changes in resting heart rates may be a reliable indicator of recovery. They theorize that when the resting heart rate becomes less variable during recovery, "the system is telling us that the brain and body are connecting properly again, and you're back online," Reed said.
If their theory holds true, heart rate variability could be a simple and objective way to assess how an athlete is recovering after a concussion, unlike more subjective measures, such as asking an athlete how he or she is feeling.
Diagnosing concussion is difficult in children because they are often less able than adults to communicate the subtle mental and physical changes they may experience after a brain injury, said Dr. Paul van Donkelaar, a CIHR grant recipient and professor of health and exercise sciences at the University of British Columbia Okanagan.
Moreover, standard tests designed for adults may not detect whether a child is having problems with short-term memory and executive function, the set of mental processes involving in decision-making, organizing information and planning complex tasks, he added.
Better clinical tools are needed to determine when it's safe for a child to return to normal activities after a concussion, he pointed out. "For kids, it's not just the return to sport but the whole issue of education – when to go back to school," van Donkelaar said.
Van Donkelaar is working with Dr. Phil Ainslie at the University of British Columbia to study the relationship between blood flow to the brain and cognitive symptoms in children who have suffered a concussion. Using an ultrasound probe attached to headgear to measure blood flow to the brain, the researchers found a correlation between increased blood flow and higher headache scores in athletes who did light exercise after mild concussions.
How to manage concussions in children remains "a great unknown," van Donkelaar said. Nevertheless, many researchers believe that mild traumatic brain injuries may be worse for kids under age 15, since they are still undergoing significant brain development. During that critical period, "you can have longer lasting effects," he said.
Ultimately, protecting young brains will require better sports gear, new rules to prevent collisions in contact sports and more sophisticated diagnostic tests to determine when a young athlete should take a time out, van Donkelaar said.
But the goal is not to deter children from contact sports, he added: "I don't want that to be an outcome of this research."