In BC Disease News, we have been monitoring chronic traumatic encephalopathy (CTE) as an emerging ‘industrial disease’. We first considered the condition in a feature article, in edition 203 (here), when an ex-professional footballer was diagnosed with the condition post-mortem, by Dr. Willie Stewart. This was closely followed by a second diagnosis, in another ex-professional footballer, which we reported in edition 243 (here).
CTE is a type of dementia, also known as dementia pugilistica, which is associated with contact sports, such as boxing, American football, football and rugby. Some experts believe that a key risk factor for the degeneration of brain function is exposure to repetitive head injury, which need not be concussive. In football, it is believed that heading of footballs is the main source of cumulative exposure to head trauma.
In January 2018, a study, entitled Football's Influence on Lifelong Health and Dementia Risk (FIELD), was selected by the Football Association’s (FA) expert panel on concussion, after an open tender process.
The study was led by Dr. Stewart, at the University of Glasgow, who invited families of former players and ex-players themselves to donate their brains to the Glasgow Brain Injury Research Group to contribute towards FIELD.
Every brain studied satisfied the criteria of having belonged to a rugby or football player who played for a sustained period of time and eventually suffered dementia.
This week, results were revealed by Dr. Stewart at the Scottish Cognitive Outcomes from Brain Injury Consortium, as reported by the Daily Telegraph. Researchers found that football and rugby players were 6 times more likely to develop CTE (75%) than the general population (12%).
‘They have a range of pathologies but the one thing that is coming through that is striking in the group we have looked at, which actually mirrors what has been found in other places around the world, is that around three quarters of them have this CTE pathology in their brains, What we are talking is roughly about six times higher level CTE pathology in the brains of these former sportsmen than you would see in other dementias. One thing we do know is that the diagnosis in life is often refined or changed when you look at post-mortem’.
Dr Stewart has, however, warned that CTE research is still at a ‘very early stage’. It is still not clear whether CTE pathology is diagnostic of dementia, or whether it is a mere indicator of exposure to brain injury. If it is the latter, you could analogise CTE pathology with pleural plaques as a marker of asbestos exposure.
He is currently leading additional research, funded by the FA and the Professional Footballers’ Association (PFA), into the prevalence of dementia among former players.
 Jeremy Wilson, ‘Study reveals former football and rugby players six times more likely to have degenerative brain disease, CTE’ (19 January 2019 The Telegraph) <https://www.telegraph.co.uk/sport/2019/01/19/study-reveals-former-football-rugby-players-six-times-likely/> accessed 22 January 2019.