What is CTE, and how many former NFL players have been diagnosed with it?

Editor’s Note: This story includes discussion of suicide. If you or someone you know needs help, the national suicide and crisis lifeline in the U.S. is available by calling or texting 988. There is also an online chat at 988lifeline.org. (NEXSTAR) – A new study led by researchers out of Massachusetts suggests that among those who have played in the NFL, at least one in four may develop chronic traumatic encephalopathy (CTE), a disease that carries no cure and has only been diagnosed after death. The study, published in The BMJ, reviewed the hundreds of NFL players who died between 2008 and 2021. Of the more than 1,700 who died, researchers reported that the brains of 338 were studied. Postmortem brain analysis has, so far, been the only proven method of determining whether someone has CTE, a degenerative brain disease. Of the 338 brains that were studied, it was determined that 315 donors had a CTE diagnosis. Among players who died within the last six years – a time in which "brain donation was more frequent" – researchers said 235 NFL players donated their brains for analysis. More than 210 were found to have CTE. Just over 200 of the 338 whose brains were analyzed had been previously diagnosed with dementia. The study found that donors with dementia were later found to have more severe cases of CTE: 94 had Stage 4 CTE, considered the most severe level. Broadly speaking, CTE impacts how the brain functions. Research has suggested that CTE is "linked to a build-up of abnorma…