Study of deceased NFL players' brains finds 99 percent had CTE

A neuropathologist discovered that, out of 111 NFL players whose brains were sent to her, 110 had CTE

By Matthew Rozsa

Staff Writer

Published July 25, 2017 4:17PM (EDT)

 (Getty/Timothy Clary)
(Getty/Timothy Clary)

The National Football League has been struggling with its image for years due to the proliferation of claims that its players are disproportionately likely to develop chronic traumatic encephalopathy (CTE), a degenerative brain disease linked to repeated head injuries.

A new study by neuropathologist Dr. Ann McKeen has just made things so much harder for them.

The findings of the study, titled "Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football," are that from "a convenience sample of 202 deceased players of American football from a brain donation program, CTE was neuropathologically diagnosed in 177 players across all levels of play (87%), including 110 of 111 former National Football League players (99%)."

McKee has noted that the findings of her study are not without flaws, noting that "there’s a tremendous selection bias." Because the brain bank that they used for their study contained a large number of samples donated by families convinced that the football player in question had CTE, the large percentage of brains to actually have the condition may be at least partially explained by that fact.

Despite this caveat, McKee made it clear that "it is no longer debatable whether or not there is a problem in football — there is a problem."

The symptoms of CTE can include confusion, depression, memory loss and dementia. Despite doctors and scientists signaling alarm bells about its dangers in football for decades, the NFL conspired to hide or confuse the issue. At one point the league went so far as to suggest that, while it acknowledged that a tackle might subject victims' brains to the same physical stresses as a violent car accident, the medical outcome would somehow be different simply because it was football. In this, they were aided not only by cooperating doctors, but the local governments and courts as well.

But the tide has turned — the growing prevalence of CTE among football players was the subject of a Will Smith movie, 2015's "Concussion," and received particular attention after the suicide of Hall of Fame linebacker Junior Seau, who played for the legendary 1994 San Diego Chargers.

By Matthew Rozsa

Matthew Rozsa is a staff writer at Salon. He received a Master's Degree in History from Rutgers-Newark in 2012 and was awarded a science journalism fellowship from the Metcalf Institute in 2022.

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