(Reuters Health) - A study of more than a thousand former professional soccer players has uncovered significantly more deaths from brain disease than among non-players.
The study, released Monday in The New England Journal of Medicine, found that neurodegenerative diseases claimed the lives of 1.7per cent of the 1,180 former Scottish soccer players compared to 0.5per cent of 3,807 non-players matched for gender, age, and socioeconomic status. That's more than a 3-fold increase.
The findings dovetail with research showing that pro athletes who play American football are at increased risk of cognitive impairment associated with repetitive brain trauma.
Among the soccer players in the new study, the rate of death from Alzheimer's disease was five times higher, and the rate of death from Parkinson's disease was twice as high, compared to the control group.
Reinforcing the finding is the discovery that former players were nearly five times more likely to have been prescribed dementia-related medications than non-players.
Goalkeepers, who head the ball less often, were 59per cent less likely to have gotten such a prescription than outfield players. However, those two groups had similar rates of death from neurodegenerative disease, which is at odds with what one might expect if heading caused cognitive problems.
Head impacts in American football tend to be more forceful, but an average soccer player heads the ball 6 to 12 times per game. Coaches also conduct heading drills during practice.
"It appears that it is not just the 'big hits' resulting in symptomatic concussions that increase the risk of neurologic disorders later in life," said Robert Stern of the Boston University Chronic Traumatic Encephalopathy Center in a Journal editorial.
However, Dr. Stern said the findings "should not engender undue fear and panic among soccer players, parents, and coaches."
As the authors noted, "it is not possible to generalize their findings among male former professional soccer players to participants in recreational, amateur, or collegiate-level soccer," he said.
For now, while more research is done to gauge the short- and long-term consequences of heading the ball, parents "should not fear that their children are destined to have cognitive decline and dementia later in life," said Dr. Stern. "Rather, they should focus on the substantial health benefits from exercise and participation in a sport that their children enjoy."
The study, led by Daniel Mackay of the University of Glasgow, also found that former players were 20per cent less likely to die from ischemic heart disease and 47per cent less likely to die from lung cancer.
SOURCES: https://bit.ly/2MXc5EE and https://bit.ly/2BAMY57; The New England Journal of Medicine, online October 21, 2019.