An estimated 75% of professional football players who died over a 15-year span had signs of chronic traumatic encephalopathy, or CTE, a study published Wednesday found.It’s the highest estimation to date.
Most recently, a study published in August by the same group estimated that one-quarter of NFL players who died in a five-year span had CTE.The new study, published in JAMA Network Open, put the figure at three times higher.Not all people with signs of CTE in the brain go on to experience cognitive decline or dementia, and some people may never experience symptoms at all.
A smaller proportion of the former players in the analysis were estimated to have dementia, about 27%, the study found.The results were surprising, said study leader Yorghos Tripodis, the director of statistics and data management at the Boston University Alzheimer’s Disease and CTE Center.Boston University houses the UNITE Brain Bank, which studies the effects of repetitive head trauma in donated brains, including the brains of athletes, military personnel and others.“I had to double-check the numbers,” Tripodis said.
Still, he said, the number is a best guess.“Right now we don’t know how to diagnose CTE when people are alive, so we are trying to estimate.”In an emailed statement, an NFL spokesperson said, in part, that the league “continuously strives to make the game of football safer, including by implementing strategies to reduce concussions and head impacts.” Repeated blows and biasWhen a person’s head jolts during an impact, the brain — which is suspended in fluid inside the skull — can slam into the skull or twist, said Dr.
Julian Bailes, chair of the neurosurgery department at Endeavor Health in the Chicago area.Each blow is an opportunity for proteins called tau to build up in the brain.
“If that happens over and over again, that damage accrues,” said Bailes, who wasn’t involved with the new research.The disease can affect parts of the brain involved w...