Brain damage evidence found in former footballers
Research carried out by UK-based not-for-profit The Drake Foundation has found evidence of chronic traumatic encephalopathy (CTE), a potential cause of dementia caused by repeated blows to the head, in the brains of former association football players.
Footballers are exposed to repetitive blows to the head from heading the ball and from head-to-player collisions. The results suggest that heading the ball over many years, a form of repetitive sub-concussive head injury, can result in the development of CTE and dementia.
The study, published in the journal Acta Neuropathologica, looked at 14 retired footballers with dementia who were referred to the Old Age Psychiatry Service in Swansea, Wales, between 1980 and 2010.
The ex-footballers monitored in the study all started playing football and heading the ball in their childhood or early teens and continued to play regularly for an average of 26 years. Only six reported concussion with loss of consciousness while playing football, limiting to a single episode each during their playing career. The earliest symptoms of dementia started while they were in their 60s and they lived for an average of 10 years after symptoms began. Twelve out of 14 of them eventually died of advanced dementia.
All of the players whose brain autopsies showed signs of CTE also had Alzheimer’s pathology, but the relationship between the two diseases remains unclear. Both diseases involve a build-up of an insoluble form of tau protein in the brain. However, in CTE tau tends to accumulate around blood vessels and at the depths of the sulci – the grooves in the brain’s surface – which helps to differentiate CTE from Alzheimer’s pathology under the microscope.
“This is the first time CTE has been confirmed in a group of retired footballers,” explains lead author Dr Helen Ling (UCL Institute of Neurology), senior research associate at the Department of Molecular Neuroscience and neurologist. “Our findings of CTE in retired footballers suggest a potential link between playing football and the development of degenerative brain pathologies in later life”.
“We do not yet know exactly what causes CTE in footballers or how significant the risk is,” says co-lead author Professor Huw Morris (UCL Institute of Neurology), Professor of Clinical Neuroscience and honorary consultant neurologist at the Royal Free Hospital and National Hospital for Neurology and Neurosurgery. “Major head injuries in football are more commonly caused by player collisions rather than heading the ball. The average footballer heads the ball thousands of times throughout their career, but this seldom causes noticeable neurological symptoms. More research is now urgently needed to determine the risks associated with playing football so that any necessary protective measures can be put in place to minimise potential long term damage.”
Previous studies have shown that the risk of Alzheimer’s disease is increased in people with previous head injuries. On the other hand, the risk of dementia is increases with age and it is not known if these footballers would have developed Alzheimer’s disease anyway if they hadn’t played football.
The most pressing research question is therefore to find out if dementia is more common in footballers than in the normal population.”
Of course, any kind of physical activity will be associated with health risks and benefits and it is well-established that playing sports can significantly improve physical and mental health.