In July, the biggest ever into football brain injuries diagnosed CTE in 99 percent of former NFL players’ brains in post-mortem examinations.
Dr Stern’s Boston University team is leading the groundbreaking and ambitious research project to identify whether there is a direct link between concussions on the field and neurodegenerative diseases in players – including the late Aaron Hernandez.
They are focusing on chronic traumatic encephalopathy (CTE), a little-understood condition a progressive neurodegeneration associated with repetitive head trauma. It has been linked to ALS (also called ‘locked-in syndrome’) and Alzheimer’s.
Now, the team has released their first major findings from post-mortem examinations on 202 deceased players’ brains, which were donated to research.
The study included a number of former NFL players, including Bubba Smith, Ken Stabler, Frank Wainright, Dave Duerson, and Junior Seau.
They also interviewed next-of-kin to learn about each player’s clinical symptoms, to compare with their findings.
The players, who lived to an average of 66 years old, had all played for a median of 15 years – from high school to professional leagues.
Overall, 177 of the brains they analyzed (87 percent) had CTE.
It was by far the most prevalent among NFL players: they found 110 of the 111 NFL players in the study (99 percent) had the hallmarks of CTE.
College players had the second-highest rate, with 48 out of 53 college players’ brains (91 percent) diagnosed with CTE.
They also diagnosed CTE in seven out of eight Canadian Football League players (88 percent), nine out of 14 semi-professional players (64 percent), and three out of 14 high school players (21 percent).
The majority of all the other players had severe pathology.
Among those with mild CTE pathology, 96 percent had behavioral and mood symptoms, 85 percent had cognitive symptoms, and 33 percent had signs of dementia.
In those with severe CTE pathology, 89 percent had behavioral or mood symptoms or both, 95 percent had cognitive symptoms, and 85 percent had signs of dementia.
CTE was usually associated with boxing before former NFL players began revealing their conditions.