A study of ex-professional soccer players in Scotland found that while they enjoy better overall health, they are at increased risk of dying due to neurodegenerative disease such as Alzheimer’s or dementia.
In recent times, there has been increased awareness of the risk of brain injury while playing contact sports such as soccer, American football, and boxing. A post-mortem analysis carried out in 2017 found that about 87% to 99% of deceased former American football players showed signs of Chronic Traumatic Encephalopathy (CTE), a form of brain damage that is associated with repeated head trauma. Statistics like these shine a spotlight on the increased risk of neurodegenerative diseases amongst contact sports players. However, studies also show that vigorous exercise and high levels of physical activity amongst competitive sports players are associated with increased life-span and better cardiovascular health compared to the general population.
Researchers in Scotland set out to carry out a risk-benefit analysis amongst former Scottish professional soccer players. The results of their study, funded by the Football Association and Professional Footballers’ Association, were published in the November issue of the New England Journal of Medicine. This retrospective study—based on data collected from past health records—compared the rates of death caused by neurodegenerative disease amongst professional soccer players to that of the general population.
The researchers accessed the health records to obtain data on cause of death and prescribed medications for dementia in a group of former soccer players born before 1977. They then used an automated computer program to match each player with individuals from the general population, in a 1:3 ratio, based on age, sex, and socio-economic background. The study thus compared records of 7676 players with 23,028 matched controls from the general population.
Overall mortality rates were about 50% lower amongst former soccer players compared to the general population. This lower rate, however, was only observed in former players up to the age of 70, after which, the rate of death from all causes was higher in this group. Death rates due to heart disease were about 40% lower in soccer players compared to the general population. Similarly, death rates due to lung cancer were about 35% lower in soccer players.
The risk of death due to neurodegenerative disease was 3.5 times higher among former players than the general population. Amongst the various neurodegenerative diseases included in this analysis, the risk of death due to Alzheimer’s disease was the highest and was lowest for those with Parkinson’s disease. There was no difference in age at death among players with neurodegenerative diseases and a similar group in the general population. Additionally, former players were 4.9 times more likely to receive a prescription for dementia-related medicine.
The design of this particular study prevented the researchers from studying the association of chronic traumatic encephalopathy, and dementia pugilistica (boxer’s dementia) with mortality rates. However, the results of this study are consistent with other studies involving players in the U.S. National Football League. Although the observations in this study may not be directly applicable to recreational or amateur soccer players, the inclusion of a large dataset with matched controls strengthens the significance of this study. As Dr. Carol Routledge, Director of Research at Alzheimer’s Research UK, remarked, “This well-conducted study of long-term health in ex-professional footballers is the largest of its kind and fills an important gap in our knowledge about football and dementia.[…] The best evidence suggests that good heart health is the best way to keep the brain healthy, so when played safely, a kick around with friends is still a great way to stay mentally and physically active.”
Written by Bhavana Achary, Ph.D
Original study- Mackay DF, Russell ER, Stewart K, MacLean JA, Pell JP, Stewart W. Neurodegenerative Disease Mortality among Former Professional Soccer Players. N Engl J Med. 2019 Nov 7;381(19):1801-1808
Data on prevalence of CTE among American football players – Lehman EJ, Hein MJ, Baron SL, Gersic CM. Neurodegenerative causes of death among retired National Football League players. Neurology. 2012;79(19):1970–1974.
Quote from Dr Carol Routledge- https://www.sciencemediacentre.org/expert-reaction-to-study-on-former-professional-footballers-and-dementia-risk/
Image by Phillip Kofler from Pixabay