MONDAY, Oct. 28, 2002 (HealthDayNews) -- High school athletes who've had at least three concussions and suffer a new one may be up to nine times more likely to suffer loss of consciousness and confusion than athletes who've never had a concussion.
That's the finding of a study in the November issue of Neurosurgery.
Previous studies indicated that more than 10 percent of American high school athletes playing contact sports suffer a concussion each season. A concussion occurs when the brain is violently rocked back and forth inside the skull. That can happen when a person receives a blow to the head or upper body.
The new study looked at 88 high school athletes who suffered concussions during the 2000-2001 school year. In that group, 60 had no prior concussion while 28 of them had had at least three.
They were compared on four concussion severity markers: loss of consciousness, confusion, anterograde amnesia (loss of memory of events after injury), and retrograde amnesia (loss of memory of events before injury).
The athletes with three or more previous concussions were nine times more likely to experience three out of the four severity markers -- loss of consciousness, anterograde amnesia and confusion.
It's the first study to indicate that prior concussions may lower an high school athlete's threshold for subsequent concussion injury and increase the severity of symptoms, says lead author Michael W. Collins, a neuropsychologist and assistant director of the University of Pittsburgh Center for Sports Medicine's concussion program.
He says high school athletes playing contact sports are at high risk for repeated concussions, but they're an understudied group in terms of managing concussions.
More information
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