Overview
- The BMJ study, published Tuesday, Aug. 25, 2026, examined 878 former NFL players who died from 2016 to 2021 and produced a conservative CTE estimate of 24.5% and a modeled maximum of 97.7%.
- Researchers reviewed 235 donated brains from that period and diagnosed CTE in 215 of them, a donor-positive rate of about 91.4% that highlights how common the disease is in self-selected samples.
- Among brain donors with CTE, 61.3% met clinical criteria for dementia before death and the most severe form of CTE, Stage IV, was linked to the highest rates of dementia and daily function loss.
- Authors and commentators caution the study’s limits because CTE can only be confirmed after death, many families donate when symptoms are suspected, and 643 decedents in the window were not examined.
- The paper calls for cutting lifetime head‑impact exposure by reducing contact in practices and youth tackle, developing living diagnostics and longitudinal studies, and expanding clinical evaluation and care for symptomatic players.