At least 1 in 4 former National Football League players who died between 2016 and 2021 had chronic traumatic encephalopathy, according to a study released on Tuesday in the journal BMJ.
The study is “one of the most informative estimates to date of CTE burden among former NFL players,” an editorial that published along with the study said.
CTE is a neurodegenerative disease associated with repeated blows to the head. It can only be diagnosed after death, although symptoms can include memory loss, impulse control problems, anxiety, depression and anger issues. It’s most often seen in people who play sports such as football, hockey and soccer, but it has also been detected in the brains of soldiers who have been injured in explosions and in some people who experienced domestic violence. In the brain, it is marked by an abnormal buildup of the protein tau.
A separate recent analysis detected the disease in 99% of former NFL players who had donated their brains for research. However, a significant limitation of that study was that it was done in a population of people who were potentially biased because their brains had been donated by family members who may have noticed symptoms while their family members were living.
