But ex-players’ reports of behavioural and emotional problems was high
Cognitive function, as assessed by standardised tests, was largely intact, among retired professional hockey players, shows the most comprehensive neuropyschological study of its kind and published online in the Journal of Neurology Neurosurgery & Psychiatry.
But former players reported high levels of behavioural and emotional problems, the findings show.
Grave concerns about the long-term impact of concussions sustained in contact sport have been raised.
The researchers compared the cognitive and behavioural functions of 33 retired professional ice hockey players, in relation to their age, concussion history, as well as genetic risk factors, with those of a comparison group of 18 healthy men of the same age who had not played professional contact sports.
Although the retired players’ performance on standardised tests showed no signs of cognitive impairment, these men reported significantly more emotional, behavioural and cognitive difficulties than the comparison group.
Both groups achieved similar results on memory and attention tests, but the retired players performed slightly less well on measures of executive and intellectual functioning. And the results of these tests were associated with the number of concussions the players had sustained.
All participants provided a blood sample for genetic analysis, to look for apolipoprotien ε4, which previous research has linked to a heightened risk of dementia. Apolipoprotien ε4 was associated with psychiatric symptoms, such as low mood, but not cognitive changes. Long term studies will be required to find out what this might mean, say the researchers.
As expected, aging affected cognitive abilities, but the effects were similar in both groups, suggesting that there was no evidence of “accelerated aging” among the retired players.
These findings provide benchmark evidence for the extent of cognitive and behavioural problems among retired professional athletes and a point of comparison for future studies, say the researchers.
In a linked editorial, Dr Alan Carson, Centre for Clinical Brain Studies, University of Edinburgh, suggests that the dangers of concussion may have been overstated.
The influence of potentially key factors, such as alcohol and substance misuse, genetics and behaviour may not have been properly accounted for, he suggests.
“Part of the problem may be that much of the debate has been played out in mainstream media rather than scientific journals,” he ventures.
“Review of the available evidence suggests that is unlikely that concussion is a risk for neurodegenerative diseases. Or, in the worst case scenario, if it does increase the risk, it only does so marginally,” he writes.
Set against any potential risk are the health benefits of participating in sport, which include helping to stave off dementia. “Ideally we need high quality studies that can give definitive answers to this question which is of considerable public concern,” he says.
A mounting body of evidence points to the value of being physically and intellectually active into old age, he points out.
“Targeting defined risks rather than speculative ones seems a far better place to start. Many elite athletes leave academic education early as a result of their dedication to sport—why not take the issue of player education on retirement far more seriously? Now that is something that might just make a difference,” he writes.
Notes for editors
Research: Cognitive and psychosocial function in retired hockey players http://jnnp.bmj.com/content/early/2017/03/10/jnnp-2016-315260
Editorial: Concussion, dementia and CTE: are we getting it very wrong?
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