For the first time, a brain disease linked with repetitive head injury in American sport has been identified in the brains of two former Australian rugby league players.
Researchers and clinicians from Royal Prince Alfred Hospital, NSW Health Pathology and the University of Sydney’s Brain and Mind Centre found evidence of Chronic Traumatic Encephalopathy, or CTE, in two brains that were referred to them for diagnostic purposes.
Their findings have been published today in the international neuropathology journal Acta Neuropathologica Communications.
“The changes in the two brains were distinctive, definitive, and met consensus diagnostic criteria for CTE,” said lead author Clinical Associate Professor Michael Buckland, Head of the RPA Neuropathology Department and Head of the Molecular Neuropathology Program at the Brain and Mind Centre.
“I have looked at about 1,000 brains over the last 10 years, and I have not seen this sort of pathology in any other case before.
“The fact that we have now seen these changes in former rugby league players indicates that they, and likely other Australian collision sports players, are not immune to CTE, a disease that has gained such high profile in the United States.”
The two cases have been published as de-identified case reports, and no further details of the players involved are available, other than they were both middle-aged former professionals who had played more than 150 first grade rugby league games over many years.
CTE was first described more than 100 years ago in boxers and was originally called punch-drunk syndrome. In younger people, it often presents with behavioural and/or mood disturbances such as depression, while symptom onset in older people may be indistinguishable from Alzheimer disease. CTE can only be diagnosed confidently by examination of the brain after death.
The only known risk factor for CTE is repetitive head injuries, in the form of concussions, and blows that do not cause signs or symptoms, known as sub-concussive impacts.
CTE has been found in the brains of former players of American Football, ice-hockey, soccer, rugby union, and others exposed to repeated head injury. The only previous case identified in an Australian sportsperson was that of Barry ‘Tizza’ Taylor, a rugby union player and coach, whose brain was sent to Boston for analysis in 2013.
Dr Christopher Nowinski, the head of the Concussion Legacy Foundation in Boston, said: “We commend the authors for this groundbreaking discovery. We hope the first proof of CTE in rugby league inspires the Australian scientific community to mobilise in the fight against CTE, and advances the conversation on reforms to sport that can prevent this disease.”
Associate Professor Buckland established the Australian Sports Brain Bank in March last year to research CTE in brains donated by the public.
So far, more than 80 athletes have pledged their brains for research.
“We encourage all athletes, their families and friends, to sign up,” Associate Professor Buckland said.
“It is only through the commitment from athletes and the sporting codes that we will fully understand the factors that cause CTE, how to minimise them, and how to effectively treat this disease.”