Elite male footballers are 1.5 times more likely to develop neurodegenerative disease compared to the general population, a new study has revealed.
In a study of male footballers, nine per cent were diagnosed with neurodegenerative disease, compared to six per cent in population controls.
And unlike outfield players, goalkeepers were found not to have an increased risk of dementia, with outfield players having a 1.4 times higher risk – supporting previous research indicating the probable role of head impacts sustained when heading the ball.
The research brought in 6,007 footballers who played in the Swedish top division between 1924 and 2019.
Its findings support previous research by Professor Willie Stewart, of the University of Glasgow, that found footballers were 3.5 times more likely to develop neurodegenerative disease, with position being a key variant in risk.
Dr Peter Ueda, assistant professor at Karolinska Institutet, Sweden, says: “While the risk increase in our study is slightly smaller than in the previous study from Scotland, it confirms that elite footballers have a greater risk of neurogenerative disease later in life.
“Importantly, our findings suggest that goalkeepers don’t have the same increased risk of neurodegenerative disease as outfield players. Goalkeepers rarely head the ball, unlike outfield players, but are exposed to similar environments and lifestyles during their football careers and perhaps also after retirement.
“It has been hypothesised that repetitive mild head trauma sustained through heading the ball is the reason football players are at increased risk, and it could be that the difference in neurodegenerative disease risk between these two types of players supports this theory.
“As there are growing calls from within the sport for greater measures to protect brain health, our study adds to the limited evidence-base and can be used to guide decisions on how to manage these risks.”
The study used Sweden’s national health registers to look for records of neurodegenerative disease (diagnoses, deaths, or use of prescription drugs for dementia) in 6,007 male football players who had played in the Swedish top division from 1924 to 2019. It compared players’ risk of neurodegenerative disease with population controls.
The analysis broke down the risk for different neurodegenerative conditions, including Alzheimer’s and other dementias, motor neuron disease, and Parkinson’s disease. It also compared the risks between outfield players and goalkeepers.
Overall, football players had a 1.5 times increased risk of neurodegenerative disease compared to controls.
However, the authors highlight that although nine per cent of football players and six per cent of controls were diagnosed with neurodegenerative disease during their study, most participants were still alive at the end of data collection, so the lifetime risk of developing neurodegenerative disease for both groups are likely to be higher.
There was no significant risk increase for football players versus controls observed for motor neuron disease, which includes ALS. The risk of Parkinson’s disease was found to be lower among football players and overall mortality was slightly lower among footballers compared to the control group (40 per cent versus 42 per cent).
Björn Pasternak, senior researcher at Karolinska Institutet, says: “The lower overall mortality we observed among footballers indicates that their overall health was better than the general population, likely because of maintaining good physical fitness from frequently playing football.
“Physical activity is associated with a lower risk of dementia, so it could be hypothesised that the potential risks from head impacts are being somewhat offset by having good physical fitness.
“Good physical fitness may also be the reason behind the lower risk of Parkinson’s disease.”
The authors point out some limitations of their study. As neurodegenerative disease usually occurs later in life, most players in the study who were old enough to have developed one of these conditions played elite football during the mid-20th century.
Since then, football has changed in many ways that may impact the risk of neurodegenerative disease.
The study also looked at male elite footballers only, so the study’s ability to extend its findings to female elite players and to male and female amateur and youth players is uncertain.
