American football: Brain disease CTE found in 99% of NFL players

Chronic traumatic encephalopathy was found in 177 of 202 players' brains, across all levels of the game.

110 of 111 NFL players' brains were found to have CTE in the study
Image: 110 of 111 NFL players' brains were found to have CTE in the study
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A report has found alarming evidence of a link between playing American football and a brain disease linked to repeated blows to the head.

The study found chronic traumatic encephalopathy, or CTE, in 177 of 202 brains of players across all levels of the game.

For those who had played in the professional National Football League (NFL), the ratio was even higher, with 110 of 111 players found to have CTE.

At other levels, the incidence of CTE varied, with three of 14 who had played only in high school found to have the disease, along with 48 of 53 college players, nine of 14 semi-professional players, and seven of eight Canadian Football League players.

CTE, which causes progressive loss of normal brain matter and an abnormal build-up of a protein called tau, was not found in the brains of two who played football before high school.

Frank Wycheck in his playing days
Image: Frank Wycheck in his playing days

However, the report, published by the Journal of the American Medical Association, is based on brains of deceased people donated to a Boston brain bank. It does not suggest CTE is common to all American football players.

In September, the NFL promised to donate $100m (£76.7m) for research aimed at making the sport safer for players.

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That followed $100m previously committed by the league to compensate former players with head injuries following multiple lawsuits alleging the league hid how much it knew about the risk of concussion.

Since 2002, the NFL has made 42 rule changes to protect players, according to league officials.

"There are many questions that remain unanswered," said lead author Dr Ann McKee, a Boston University neuroscientist.

"How common is this in the general population and all football players?," Dr McKee asked.

"How many years of football is too many and what is the genetic risk? Some players do not have evidence of this disease despite long playing years," she added.

She also warned that it is also uncertain if some players' lifestyle habits, such as use of alcohol, drugs and steroids, as well as diet, might also contribute.

As well as referencing famous cases such as former NFL players with CTE, such as Bubba Smith, Ken Stabler, Junior Seau and Dave Duerson, the study discussed new ones such as Frank Wycheck.

The 45-year-old former NFL player said: "Some people have heads made of concrete, and it doesn't really affect some of those guys. But CTE is real.

"I know I'm suffering through it, and it's been a struggle."

The average age of death among all players studied was 66. There were 18 suicides among the 177 diagnosed.