Boston University Study Estimates 75% of Deceased Ex-NFL Players Had CTE
A new study published in JAMA Network Open estimates that approximately 75% of former NFL players who died between 2008 and 2023 had chronic traumatic encephalopathy (CTE). Researchers from Boston University analyzed data from 2,362 deceased players, finding that 93.5% of those who donated their brains had CTE. After adjusting for donation bias, the study suggests a higher prevalence than previous estimates. The findings highlight the link between repetitive head impacts and neurodegenerative disease, prompting discussions on youth safety protocols and early detection methods.
Key points
- The study estimates 75% of former NFL players who died between 2008 and 2023 had CTE.
- Among 2,362 deceased players, 396 donated brains, with 93.5% of those donors diagnosed with CTE.
- Researchers adjusted for donation bias, noting that players with cognitive symptoms were five times more likely to donate.
- CTE is linked to repetitive head impacts and causes abnormal buildup of the protein tau.
- The NFL stated it is committed to safety resources and reducing head impacts.
- Experts noted that CTE does not always result in symptoms, but severe cases are linked to dementia.
Background
Previous studies had found CTE in up to 99% of former NFL players who donated their brains, but these figures were limited by selection bias. An August 2026 study estimated that at least 25% of former players who died between 2016 and 2021 had CTE. This new study aims to provide a broader estimate by including non-donors and adjusting for the likelihood of brain donation based on symptoms and age.
How outlets are covering it
The primary source, WJCL, highlights the statistical methodology and the NFL's response regarding safety resources. WEAR-TV emphasizes the local impact, featuring a pediatric neurosurgeon who advises against youth contact sports due to high concussion risks, and a high school coach detailing current concussion protocols. ESPN's content was inaccessible due to a 403 error, so no perspective could be extracted. The primary source notes that while CTE is prevalent, not all players with the disease exhibit symptoms, whereas WEAR-TV focuses on the irreversible nature of the disease and the importance of prevention.
Why it matters
The study provides a more comprehensive estimate of CTE prevalence among former NFL players, highlighting the long-term health risks of professional football. It underscores the need for improved early detection methods and safety protocols in youth sports to mitigate the risk of neurodegenerative diseases. The findings may influence policy discussions regarding head impact reduction in practice and game settings.
What to watch
Researchers plan to use these findings to advance diagnostic criteria for living patients and design clinical trials for potential cures. The NFL and other stakeholders may review safety protocols, particularly in youth levels, to reduce head impacts. Experts continue to debate the balance between the benefits of contact sports and the risks of CTE, with some advocating for stricter rules in practice settings.
- New study suggests 3 in 4 former NFL players who died from 2008 to 2023 had CTE WJCL
- Study: Estimated 75% of NFL players who died from 2008 to 2023 had CTE ESPN
- A major BU study provides what could be the clearest look yet at how CTE has affected NFL players. The results are startling. The Boston Globe
- Can Scientists Make Football Safer? The New York Times
- PHS uses concussion protocol as new study reveals long-term effects of playing football WEAR-TV
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