By Greg Baum
Freshly published American research has established a new link between playing contact sport, CTE, and the development of a movement disorder known as Parkinsonism.
CTE, or Chronic Traumatic Encephalopathy, is a degenerative disease believed to be caused by repeated blows to the head that can be diagnosed only after death. It has been found in Australia in former AFL stars Polly Farmer, Danny Frawley and Shane Tuck, among others.
Geelong legend Graham “Polly” Farmer was found to have had CTE.
Parkinsonism is an umbrella term for a suite of conditions that includes Parkinson’s disease and is characterised by tremors, abnormal slowness of movement, or abnormal stiffness in arms or legs.
The study of 481 deceased athletes by researchers at Boston University’s Chobanian and Avedisian School of Medicine and VA Boston Healthcare revealed that most people found with CTE had developed Parkinsonism and CTE pathology appeared to be driving the Parkinsonism symptoms in most cases.
Brain injury expert Dr Alan Pearce.Credit: Simon Schluter
One of the authors of the study, Associate Professor Thor Stein, said researchers were surprised to find that their subjects did not show classic Parkinson’s pathology, which is associated with the build-up of proteins called Lewy bodies in brain cells.
“Rather, subjects with Parkinsonism were more likely to have more severe CTE-related brain cell death in a region of the brain stem important for controlling movement,” Dr Stein said.
The results struck a chord with Dr Alan Pearce, an Australian neuroscientist and leading researcher into concussion and CTE.
“Movement disorders have tended to be downplayed a bit because of the dominant thinking around cognitive and mental issues,” Dr Pearce said. “As someone who has done most of my work in that movement disorder area, I’m actually not surprised.”
Dr Pearce said he had seen symptoms of Parkinsonism in a number of CTE cases in which he has been involved.
Put succinctly, Dr Pearce said, if someone suddenly forgets where they are, alarm bells ring. But if someone shuffles a bit, they’re dismissed as simply getting old.
Dr Pearce characterised movement disorder as a loss of fine motor or movement control. “It’s anything from threading a needle or being able to put finger and thumb together, to more significant issues such as a shuffling gait and a risk of falling,” he said.
CTE is now linked to Parkinsonism.Credit: Jo Gay
“This research is quite significant because we’ve always thought about the mental issues, and memory, and focusing, and concentration, but we’ve rarely spoken about movement. And movement is obviously so key to us being human.”
Put succinctly, Dr Pearce said, if someone suddenly forgets where they are, alarm bells ring. But if someone shuffles a bit, they’re dismissed as simply getting old.
A 2018 study by the same Boston research team found that the longer an athlete played a contact sport, the shorter were the odds of developing Lewy body disease linked to Parkinson’s. But the new study is the first to unearth a link between contact sport, brain stem pathology and Parkinsonism.
“Increased CTE severity has been shown to be associated with longer duration of play,” said Daniel Kirsch, an MD/PhD student and one of the authors of the study. “In this study, we found that an additional eight years of contact was associated with a 50 per cent increased risk of more severe disease in a specific area of the brain stem that controls movement.”
In a press release accompanying their findings, the researchers said: “This study underscores the importance of understanding the long-term effects of repetitive head impacts and the need for preventive measures in contact sports to mitigate the risk of neurodegenerative diseases like CTE and Parkinsonism.”
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