If you have suffered a concussion through a sport or recreational activity, there is about a one in three chance that you’ll suffer a second or third related concussion, say researchers with the University of Alberta.

Using data gathered on emergency room visits in Edmonton, School of Public Health professor Don Voaklander and graduate student Andrew Harris identified patterns emerging regarding individuals reporting repeated head injury. 

Once someone has a head injury, they are much more susceptible to further head trauma. In fact, the research, recently reported in the Clinical Journal of Sport Medicine, shows that people with a previous head injury are nearly three times more likely to have an additional head injury. This likelihood increases to nearly seven times for those who sustained two previous head injuries.

In light of an increasing incidence of head injury, Voaklander, who is also director of the Alberta Centre for Injury Control and Research, decided to revisit the data. This time, the aim was to determine what happened after a first head injury was reported. “We know that in the last five years there has been more awareness of head injury and concussions,” says Voaklander. “We wanted to follow up on the data to see if one possible concussion made people more susceptible to a second or third possible concussion.”

“This study is unique because the data are gathered from the immediate community,” says Harris, noting that, typically, this type of research focuses on university and professional athletes, and not sport and recreation related concussions in the general population. “These data are indicative of what is happening to the average Edmontonian.”

“Unfortunately, we don’t know the risk profile of the age groups,” says Harris. “But we do know that, in the 7 to 13 year age group, kids are still likely engaged in family activity and aren’t taking the same risks as the 14 to 18 year age group.”

The researchers also note that the data may understate the problem of head injury as the number of people who don’t disclose if they’ve had a concussion is unknown.

Harris and Voaklander believe that, no matter what the rules of a sports and recreational activity are, and how well you are protected, concussion can still occur. According to the research, the greatest risk of head injury occurs in animal-related activities such as horseback riding, as well as playing rugby and operating an ATV. The odds of sustaining a head injury related to skiing, snowboarding or sledding is nearly the same to that of playing football.

“You have to think about the sport you play and where the energy is,” explains Voaklander. “If you’re playing hockey or football, you’re reasonably well protected with equipment and the energy comes from your own body. If you’re riding a bike, using an ATV or riding a horse, the energy is no longer coming from you, and you’re no longer at ground level should you fall.”

“You can put the best helmets on people, but that doesn’t protect the brain from the acceleration and deceleration that comes from sport and recreation,” states Voaklander. Often head injury occurs even while wearing a helmet since the sheer force of the impact from activity can bruise the brain.

Based on the evidence, both researchers say there may be cause to push for further changes in sport and recreation. Currently, a number of U.S. states have implemented “return to play” laws, making it more difficult for people to get back onto the playing field without first being assessed by a trained medical professional.

“Unfortunately, kids end up seeing professional players pushing the limit and playing through serious injury,” says Voaklander. He adds that, if you’ve had multiple concussions, you could end up losing a sport that you love.

The researchers would like to see prevention programs adopted in both the community and medical settings to target young people who sustain head injury.