Study - Nearly 75% of NFLers who died from 2008 to 2023 had CTE - ESPN

An estimated 75% of former NFL players who died between 2008 and 2023 had chronic traumatic encephalopathy, or CTE, the neurodegenerative brain disease tied to high-impact sports such as football, according to a new study released Wednesday.

The study, published in JAMA Network Open by researchers at Boston University, Mass General Brigham and the Concussion & CTE Foundation, said it marked the first comprehensive effort by scientists to understand the prevalence of CTE among deceased former NFL players.

Some of the same researchers published a paper in August that estimated that 1 in 4 former NFL players who died between 2016 and 2021 had CTE.

The neurodegenerative disease is diagnosable only after death, and research into finding a CTE test during life is ongoing.

The researchers cautioned that the estimate applies only to deceased NFL players and does not predict the prevalence of CTE in living NFL players. The study also doesn't address prevalence among college or youth football players. Among other caveats were that the study doesn't indicate what, if any, symptoms had manifested in the players that might have been related to CTE.

CTE is identified in stages ranging from I to IV based on severity. Symptoms often don't manifest in the earliest stages, according to researchers.

«Many cases may have been early stage at the time of death and possibly symptom free,» the paper said.

Julia Gallini, the lead author on the paper, said in a statement that the nearly 75% estimated prevalence was «concerning» and that more effort needed to be made «to support families, diagnose CTE during life, and treat CTE-related symptoms.»

Past research into CTE has drawn criticism for selection bias because of its reliance on brains