A new study has offered the first evidence CTE, a concussion-related brain disease, can be identified in living athletes, a discovery experts say could shake up the way professional sports treats concussions and head trauma in players.
Currently, chronic traumatic encephalopathy (CTE) is diagnosed only after death, using an autopsy. The new findings are a step toward identifying the disease while players are still alive. “It suggests we’re on the right track,” UCLA neuroscientist Gary Small, an Alzheimer’s specialist and lead author on the study, said in an interview.
“We have an approach or a strategy to detect the problem early so we can develop treatments before there’s extensive damage.”
In the study, published Tuesday in the American Journal of Geriatric Psychiatry, UCLA researchers injected a biomarker into five retired NFL players ages 45 to 73 with a history of CTE symptoms, as well as a control group of healthy adults. They then ran all the participants through a brain scan to look for tau proteins, an indicator of CTE, locating significant amounts in the retired players’ brains.
Experts believe CTE can develop in athletes after repeated minor head injuries. Symptoms can include depression, dementia, memory loss and suicidal behaviour, according to previous studies.
Signs of the disease were identified earlier this month in the brain of Pro Bowl linebacker Junior Seau, who fatally shot himself in the chest last year. CTE has also been diagnosed in post-mortem examinations of former NHL enforcers Derek Boogaard and Bob Probert.
Since CTE was first identified about a decade ago, the disease has also been found in brain tissue belonging to dozens of former American and Canadian football players, most notably through research conducted at the U.S.-based Brain Injury Research Institute, which funded Small’s research.
It has become a flashpoint for concussion experts, who say professional sports leagues are not doing enough to mitigate the potential for head trauma. A study released by the U.S. government last September found ex-football players were four times more likely than the average person to die from an illness related to brain trauma.
“Of course, everyone is interested in the ability to diagnose (CTE) in people who are living because that opens up important avenues for better management and treatment research to either prevent or offset the consequences of the disease,” said Robin Green, a brain injury specialist at the Toronto Rehabilitation Institute and Canadian Sports Concussion Project who did not work on the new study.
The findings come amidst an upsurge of action (and controversial inaction) by leagues to address the issue. The NFL has committed million of dollars to fund brain research and has taken steps to reduce the risk of in-game head injuries through fines for inappropriately aggressive hits. Still, more than 4,000 former players are behind a U.S. federal lawsuit against the NFL, alleging the league has been negligent in preventing head injuries.
The UCLA study uses a biomarker that has been used to track Alzheimer’s. According to the study, it is the only imaging substance that can locate tau in living people. This, the authors say, is the first study to apply it to CTE.
Among the players tested, the biomarker revealed excessive amounts of tau in regions of the brain that control emotions and behaviour. Researchers found “a straight line” between the number of concussions the players had suffered and the amount of tau protein in their brains, Small said.
“That goes along with other studies that show if you have three or more concussions, it increases your risk for mild cognitive impairment and depression symptoms,” he said.
Small stressed the study is only the first step in studying brain degeneration in living athletes with histories of repeated head trauma. That the UCLA study only examines five players is a limitation, said Charles Tator, a Toronto neurologist and head of the Canadian Sports Concussion Project.
Researchers involved with Tator’s project are now attempting to find tau proteins in a larger group of 40 retired, living CFL players.
“To really be sure of findings of this nature, you probably need about 50 patients to be 100 per cent sure,” Tator said.