Study finds NFL players about four times more likely to die from neurodegenerative disease
Researchers from Mass General Brigham, Boston University and the Concussion & CTE Foundation reviewed death records for nearly 20,000 players spanning 1960 to 2019.
A new study reports that NFL players are roughly four times more likely than the general population to die from a neurodegenerative disease, adding population-level data to a topic the league has grappled with for years. The research, conducted by Mass General Brigham, Boston University and the Concussion & CTE Foundation, is described as the largest retrospective cohort study of its kind. Its authors framed the findings as evidence of measurably higher rates, while also cautioning about the limits of the records they used.
What did the study find?
Researchers reported that former NFL players are about four times more likely than the general population to die from a neurodegenerative disease. The study examined 19,824 NFL athletes who played between 1960 and 2019, of whom 1,994 had died, and drew on death certificate data from the Centers for Disease Control and Prevention. Dr. Daniel Daneshvar of Mass General Brigham said the results represent "the clearest population-level evidence we have ever had that NFL players are dying due to neurodegenerative disease at real and measurably higher rates." The diseases noted in the findings include dementia and Parkinson's disease. The authors described the work as the biggest retrospective cohort study on the question to date. They did not claim the study proves a single cause for every death, but pointed to a consistent pattern across the group.
Were some players at higher risk than others?
The study found the elevated risk was not uniform across the player population. Athletes who died before the age of 60 showed a rate roughly 12 times higher than the comparison group, according to the research. Skill-position players carried about twice the risk of linemen, the study reported. Daneshvar tied the broader findings to head impacts, saying that "the most effective way to decrease someone's risk of neurodegenerative disease is to decrease the total amount of force to the head they've experienced." The researchers presented these breakdowns as observed differences within the data rather than as proof of a specific mechanism for any individual. The variation by position and age was among the more detailed results the authors highlighted.
What limitations did the researchers note?
The authors were direct about the constraints of their data. Death certificates are often imprecise about cause of death, which the researchers said means the true rates of neurodegenerative disease are likely higher than what the records show. They also noted that competing factors, such as longer amateur careers and changes in how athletes train and play over the decades, could mask any safety improvements that rule changes have produced. Because the study is retrospective and built on existing records rather than direct clinical diagnosis, it describes associations rather than establishing cause and effect for every case. The researchers presented the numbers as a population-level signal that warrants further study. As of the report, an NFL spokesman had not responded to a request for comment.
How does this fit with recent player brain-health stories?
The study arrives during an offseason in which individual brain-health cases have drawn attention. The family of Aldon Smith arranged for his brain to be examined for chronic traumatic encephalopathy following his death. Chris Johnson disclosed an ALS diagnosis and has pushed to revive the Ice Bucket Challenge to raise money and awareness. This research offers the broader statistical backdrop behind those individual accounts, moving from single cases to a large group tracked over six decades. It does not diagnose any specific player, but it helps explain why brain health has remained a persistent subject around the sport. The findings are likely to inform continued debate over head impacts and player safety.
Sources
- ESPN: Study - NFL players are 4 times more likely to die from neurodegenerative disease
