Repetitive hits to the head may cause Chronic Traumatic Encephalopathy (CTE) even without signs of concussion, a study of neurodegenerative disease suggests.
The Alzheimer's-like disease has predominantly been associated with former professional football players and military veterans, who are prone to head injuries, and it has widely been accepted that concussions are linked to CTE, National Public Radio noted.
Now researchers from Boston University say they have found the most conclusive proof that it could just take repetitive hits to the head, without symptoms of concussion, to set off the disease.
"Now we have both the scientific proof, the pathologies to support it, and all the evidence to show that concussion is not linked to long-term neurological disease," said Dr. Lee Goldstein, one of the authors on the study published in the journal Brain, according to CNN.
The study examined the brains of four deceased football athletes who had passed away within days and weeks of sustaining a sport-related head injury.
Researchers noted changes to the brain that were indicators of CTE.
"We're seeing the earliest pathology soon after one of these injuries," Goldstein said.
The ground-breaking evidence highlights a new cause for concern.
"The concussions we see on the ballfield or the battlefield or wherever — those people are going to get attention, because it's obvious they've had some sort of injury," said Goldstein, according to National Public Radio. "We're really worried about the many more people who are getting hit and getting hurt — their brain is getting hurt — but are not getting help because we can't see the evidence on the outside that their brain is actually hurt. It's a silent injury."
Goldstein said he hoped this new information would be taken into consideration by football policy makers, professional players and parents, noting that it was important to now focus on ways to reduce overall exposure to repeated hits, KCCI reported.
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