Seven of the 334 deceased players had Alzheimer's and seven had ALS, the researchers report today in the journal Neurology.
Risks were highest in players who played high-speed positions, including quarterbacks, running backs, halfbacks, fullbacks, wide receivers, tight ends, defensive backs, safeties and linebackers. Compared to offensive and defensive linemen, they were more than three times more likely to die from neurodegenerative diseases.
The study adds to previous research, including evidence that retired football players who had suffered three or more concussions were five times more likely than normal to have mild cognitive disorders and three times more likely to suffer significant memory problems.
"Although the results of our study do not establish a cause-effect relationship between football-related concussion and death from neurodegenerative disorders," wrote the researchers, from the Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health, "they do provide additional support for the finding that professional football players are at an increased risk of death from neurodegenerative causes."
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