WINNIPEG – Around 25 per cent of former National Football League players, who died between 2016 and 2021, had evidence of chronic traumatic encephalopathy, or CTE, at the time of death.
This is according to a new study published in the British Medical Journal (BMJ), which focused on how common CTE might be among NFL players.
CTE, which can only be diagnosed after death, is a degenerative brain disease caused by repeated head injuries. Most research has depended on brains donated by players or their families.
Researchers examined 235 donated brains from a group of 878 former NFL players who died during the six-year period. CTE was found in 215 of the 235 brains examined.
According to Brain Injury Canada, CTE includes a range of symptoms, including memory and thought processing problems, and changes in personality such as aggression and impulsivity.
Advanced CTE can develop into dementia, and symptoms don’t normally appear until several years after the trauma occurred.
“We were definitely surprised at how common it was amongst our donors and how reflective our donors were of the overall cohort,” said Dr. Daniel Daneshvar, chair of Physical Medical Rehabilitation at Mass General Brigham and Harvard Medical School, and the lead author of the study.
“We’ve known for some time that these repeated traumatic brain injuries can cause problems later in life, but just seeing that difference between less than one per cent of the general population, and at the very least 25 per cent of NFL players, was remarkable.”
Daneshvar said the findings also included former players who died at relatively young ages.
“We had seven people unfortunately pass away in their 20s. We had another more than a dozen pass away in their 30s, so those reflect people who played in the more modern era, as well,” he said.
The study also examined the relationship between CTE and dementia, finding that more than 90 per cent of individuals with the most advanced stage of CTE, Stage 4, were also diagnosed with dementia.
‘The reality is likely much higher’: expert
Dr. Carmela Tartaglia, a clinician scientist at University Health Network’s Krembil Brain Institute, said the findings reinforce the link between repetitive head impacts and neurodegenerative disease.
“More prevention is required to make these sports as safe as possible,” Tartaglia told CTV News.
She also cautioned that the study’s findings likely represent a minimum estimate.
“It’s important to stress that the study found one in four former players is the lowest incidence, but the reality is likely much higher.”
Dr. Lesley Ritchie from the University of Manitoba says while CTE is a concern within high-exposure cohorts, it remains rare among the general population.
“Most people who experience a concussion or repetitive head injuries fully recover from their injuries and do not experience significant decline later in life (related to the head trauma),” said Ritchie, an assistant professor in the department of clinical health psychology.
“The results of the BMJ study are specific to a cohort of former NFL players and cannot be generalized to living players, athletes in other sports, or the broader sporting community.”
Professional sports leagues have implemented measures to protect players in recent years, including the NFL, which have allowed players to wear extra protective caps.
Tim Fleiszer, who is a former Canadian Football League (CFL) player and head of the advocacy group Concussion Legacy Foundation Canada, says more needs to be done to protect young athletes.
“Children under the age of 12 or 13 should not have any sort of exposure, and what I mean by that is no headers in soccer, no tackling in football or rugby, no body checking in hockey which fortunately, Hockey Canada has already made that policy change some years back,” he said.
Fleiszer would like to see national legislation similar to Rowan’s Law in Ontario, named in honour of Ottawa teen and rugby player Rowan Stringer who died from second-impact syndrome in 2013.
The law, which was introduced in 2018, sets out a framework for how coaches, parents, team trainers, and athletes should respond if a brain injury is suspected during sports or recreational activities.
A study, which was released last year, found that between 2018 and 2019, Ontario saw a nine per cent drop in sport-related traumatic injuries, following the implementation of that legislation.
“We should look at provincial and federal governments to have pan-Canadian legislation that addresses brain injury,” he said.
“We should be reducing the impacts that athletes receive during the course of their career, particularly in practice, which is what you’ve seen in the NFL and in the CFL, where there’s now very strict limits on contact in practice.”
Football taking steps to make game safer
Bill Johnson with Football Manitoba says there is risk in playing football, but as an organization, they are doing everything they can to mitigate it.
“We have safe contact training for our coaches and our athletes, where they’re taught basically how to hit without having their head involved in the play,” said Johnson, who is the organization’s executive director.
“We have helmet technology that’s changed, drastically, and we have programs where we make sure that those helmets are going in for reconditioning every two years, so we can make sure that they’re as safe as possible.”
Johnson says safety and protection of young athletes has become a major tool in the sport.
“I’ve been involved in football for ten years now, and I’ve been very impressed with this sport in terms of how they are proactive in their approach to these things and constantly trying to make the game as safe as possible,” he said.
