No less than 25 percent of deceased former NFL players who died from 2016 to 2021 were found to have had chronic traumatic encephalopathy (CTE), according to a study released Tuesday.
CTE is a form of brain injury linked to repeated blows to the head.
The study is raising alarms, given that the 25 percent figure represents a much higher CTE occurrence rate than has been reported in previous studies.
The disease can only be detected in the brains of deceased persons.
Not only was there a high percentage of CTE detected, but researchers also found that a whopping 61.3 percent of those brains found to have CTE also met the clinical criteria for dementia, strengthening the link between severe CTE and dementia.
An NFL spokesperson told CBS News the league “continuously strives to make the game of football safer, including by implementing strategies to reduce concussions and head impacts.”
“The NFL remains committed to ensuring that the NFL community has access to a robust — and expanding — set of resources to enhance their physical and mental well-being. We encourage former players to utilize these resources to identify and seek treatment when they are concerned about their health.”
The study was conducted by Mass General Brigham, Boston University, and the Concussion & CTE Foundation, and was published in The British Medical Journal.
Researchers stress that the actual prevalence of CTE in former players could be much higher.
Of the 878 former NFL players who died between 2016 and 2021, 235 donated their brains to research. Of those 235, 215 brains were found to contain CTE (91.4%).
The numbers fell to “at least 25 percent” only after factoring in the number of players who did not donate their brains. The estimated numbers researchers gave for the prevalence of CTE among all ex-NFL players who passed away between 2016 and 2021 were between 24.5% and 97.7%.
“The true prevalence likely lies somewhere in the middle,” the researchers said.