The brains of 2 in 5 athletes aged under 30 that were donated to a leading research program at Boston University had early-stage chronic traumatic encephalopathy – a degenerative brain injury of chief concern to sports bodies around the world.
Chronic traumatic encephalopathy (CTE) has been a prominent issue around the world in 2023 with several studies shedding light on the potential long-term effect of repeated head impacts on athlete brain health.
Repeated head impacts can lead to several persistent cognitive and neuropsychiatric symptoms. CTE is a neurodegenerative disease that leads to a range of effects, including memory loss, confusion and decision-making impairments, challenges with impulse control and aggression, and depression and anxiety.
But it can only be confirmed by inspecting ‘slides’ of brain tissue under a microscope after death. It’s why athletes who suspect they may have the disease, or their families, agree to provide their brains to brain banks around the world.
An Australian Senate enquiry into the influence of concussion in community sport is to report shortly, amid several high-profile retirements in major football codes and the first confirmed CTE case in a female athlete increasing scrutiny on concussion management at the elite level.
A newly released study from the long-established Boston University CTE Centre, scrutinised the brains of American football, ice hockey, soccer and rugby players, and wrestlers who died before the age of 30 – mainly due to suicide or accidental drug overdose. Their brains were subsequently donated to the CTE Center’s Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) study.
Of 152 brains from this donor group, 41% evaluated by the Boston study were found to have CTE, predominantly in the early stages of the disease. Of these, donors were more likely to be older, black and, college educated. One woman was also diagnosed with CTE.
Of the athletes diagnosed with Stage III CTE, two played professionally.
The researchers caution that while these donors were exposed to repetitive head impacts throughout their youth and displayed symptoms associated with CTE, further studies should compare these donors to individuals without a history of repeat impacts to “clarify the association among exposure, white matter and microvascular pathologic findings, CTE, and clinical symptoms”.
While not everyone who plays a sport is exposed to repeated head impacts, it is considered a primary risk factor for developing CTE.
Those diagnosed with CTE in the Boston study tended to be older, American football players with longer playing careers and more likely at a professional level. This, the researchers say “emphasise[s] the dual roles of age and duration of exposure to RHI in the development of CTE, even among younger individuals”.
“This is a disease of exposure… while age obviously has an influence on the risk profile of getting CTE, what it says is that if you start contact sports, and you are specialising in these contact sports from a young age, then your risk is going to be much higher,” says Professor Alan Pearce, a neuroscientist from Latrobe University, not involved with the Boston study.
Pearce is a leading voice among Australian neuroscientists and has been calling for uniform adoption of concussion and head injury protocols across sports codes, and the restriction of contact exposure in children.
He’s hoping the Senate Standing Committees on Community Affairs report into concussions and repeated head trauma in contact sports will push towards mandating standardised concussion management.
“My hope is that there will be some sort of minimum standards across all sports so that there’s some continuity. AFL seems to have 12 days, for example, with their concussion protocol, NRL have 11, but at state level they have 14, netball and basketball all have something different. It’s just, it’s just so disparate.”