Just in time for football season, a new study finds that National Football League players suffer more than just their fair share of soreness. According to the study, pro football players are three times more likely than others to die of a neurodegenerative brain disease, such as Alzheimer’s or ALS, also known as Lou Gehrig’s disease.
The findings are based on an analysis of death certificates of 3,439 former NFL players, who had played at least five seasons between 1959 and 1988. By 2007, about 10%, or 334 of the participants, had died (at an average age of 57), and the researchers looked for deaths caused by Alzheimer’s disease, Parkinson’s disease and ALS (amyotrophic lateral sclerosis).
Overall, the players appeared to be in exceptional health: at any given time, they were half as likely to die as other men their age. But when focusing on neurogenerative brain disease as the cause of death, the researchers found that ex-NFL players were at three times the risk. When researchers focused on Alzheimer’s and ALS specifically, they found that NFL players were four times more likely to die of these causes compared with the general population.
Among the 334 who died during the study period, seven had Alzheimer’s disease and seven had ALS — significantly higher rates than what would be expected in the general population. Three players died from Parkinson’s, also an elevated number, but one that did not reach statistical significance, the authors noted.
The research team also looked at differences in risk between players in “speed” versus “non-speed” positions — the former being more likely to endure higher-speed on-field collisions. Participants who played speed positions, including quarterbacks, running backs, wide receivers and linebackers, were more than three times more likely to die of brain diseases than those in non-speed positions like defensive and offensive linemen. The majority of the participants in the study had played speed positions.
The authors acknowledge that their study size was small, and that they cannot confirm a cause-and-effect relationship between repeated football-related head injuries and the risk of death from brain disease. However, they say the findings support the evidence that pro football players are at a higher risk of developing neurodegenerative disease and other neurological disorders. Data show that players who suffer more concussions are more likely to develop mild cognitive impairment, memory problems and, notably, chronic traumatic encephalopathy (CTE), a degenerative disease that causes dementia and looks a lot like Alzheimer’s.
The authors note that while they looked for Alzheimer’s, Parkinson’s and ALS as causes of death, it’s possible that some of the players in their study could have really died from CTE. “Recent research now suggests that CTE may have been the true primary or secondary factor in some of these deaths,” the authors write. Not only do CTE symptoms sometimes look like those of other neurodegenerative diseases, but CTE is also not yet listed as an official cause of death in the International Classification of Diseases and therefore wouldn’t appear on death certificates.
The new study, published in the journal Neurology, was released on the same day that the NFL pledged $30 million for medical research to the Foundation for the National Institutes of Health. The money will be overseen by the NIH and may go toward research on CTE, concussion management and treatment, and disease like Alzheimer’s, the football league said.
The league currently faces lawsuits from about 3,400 former players or their families who say that the NFL downplayed and misrepresented the risks of head injury and concussion to players. The players say their injuries led to depression, memory loss and other neurological problems. The league denies the allegations in the lawsuits and says it never withheld information about the dangers.
“Well before this study was released, the NFL took significant steps to address head injuries in football, provide medical and financial assistance to our retired players, and raise awareness of the most effective ways to prevent, manage and treat concussions,” said league spokesman Brian McCarthy in a statement, according to the Los Angeles Times.
The new study calls for further research into all factors that may underlie the risk of developing brain disease among NFL players. As other researchers have noted, the new study may underestimate the true long-term risks of repeated head injury to modern-day football players. The study included ex-NFLers from a past era, when players weren’t as big or strong or fast as they are today. “The game’s changed a lot since then in ways that are potentially worse for player’s outcomes,” Steve Marshall, an epidemiologist at the University of North Carolina, told the L.A. Times.