Kids With Past Concussions Take Longer to Recover
Study has implications for how long children should wait to resume activities, experts say
One of the big remaining questions, though, is whether kids with repeat concussions suffer any long-term consequences, Yeates said.
"We don't know if there are any effects on long-term cognition or memory," study author Eisenberg agreed. There have been reports that professional athletes who suffer blows to the head may be at heightened risk of degenerative brain diseases later on. A recent study found increased risks of Alzheimer's and Lou Gehrig's disease in retired pro football players, for example.
But Eisenberg pointed out that those athletes are routinely exposed to high-impact collisions. No one knows if kids' concussions, even repeat ones, would translate to health effects down the road.
According the U.S. Centers for Disease Control and Prevention, more than 173,000 U.S. children and teens land in the ER each year because of a concussion sustained in sports or recreational activities, like bike riding.
Concussion symptoms include headache, dizziness, nausea, ringing in the ears, fatigue and confusion -- though these problems may not become noticeable until hours after the jolt to the head. And contrary to popular belief, concussions usually do not involve loss of consciousness.
The current findings are based on 280 11- to 22-year-olds treated at the Boston Children's ER for a concussion. Of these, 21 patients had a concussion within the past year; and typically, Eisenberg's team found, their recovery from the current injury was three times longer, versus the recovery times of kids who'd never had a concussion before.
It's not clear, though, whether that high-risk time window actually lasts a whole year. "We need to figure out, more specifically, what the vulnerable window is," Eisenberg said. "Is it one month? Is it three months? We don't know."
Both Eisenberg and Yeates said they are big supporters of sports and exercise, and they would not want parents to keep their kids out of activities over concussion fears.
But both also said that if your child has suffered more than one concussion in a particular sport, it may be time to think about changing to a different activity.
"We don't know what the long-term risks might be," Yeates said. "But since we don't know, it seems best to be conservative and assume it's not good for kids to have multiple concussions."