A study into the health of retired rugby players in New Zealand has established a link between concussion and cognitive difficulties.
The long-awaited paper, which went "live" in online journal Sports Medicine this morning, is the first to be published from the fractious study carried out by AUT in partnership with New Zealand Rugby. The study was financially supported by World Rugby.
It found that a history of concussion was associated with "small to moderate cognitive difficulties in athletes following their retirement from competitive sport".
Players who had suffered one or multiple concussion performed worse on cognitive flexibility (the ability to switch attention between tasks), complex attention (the ability to track and respond to information over lengthy periods of time) and executive function (managing rapid decision making) than those who had no history of concussion.
The players were measured via an online neuropsychological test.
The study of 366 retired athletes was broken into three groups: elite rugby, community rugby and non-contact sportsmen. As would be expected, those in the two rugby groups were found to have suffered more concussions than the non-contact group. Some 85 per cent of elite rugby players reported at least one concussion, as opposed to 23 per cent in the non-contact group.
The paper, lead authored by Patria Hume, is the latest in a long line of literature linking head trauma with cognitive issues, ranging from long-term headaches to CTE and dementia.
A release in conjunction with the publication of this article stated: "Concussive head impacts are known to produce changes in the brain that may result in a temporary decline in thinking abilities, and may potentiate long-term cognitive deficits similar to those associated with the ageing process. Studies have also indicated head trauma in sport has negative short-term and cumulative neurocognitive effects."
This year, the Herald ran a series of unscientific articles, chronicling the problems of several former All Blacks.
A feature piece followed the misfortunes of several players in the triumphant Taranaki Ranfurly Shield side of 1964. One player, former All Black five-eight Neil Wolfe, said: "I have a little bit of dementia now, and I suppose it relates back to the time when I was playing rugby and did get knocked out."
In June the Herald reported that New Zealand Rugby had partnered with Statistics NZ to try to determine whether the lasting impacts of concussions while playing rugby increase the risk of dementia.
The project is in its early stages but NZ Rugby hopes the findings will provide "robust answers to that critical question".
NZ Rugby will use the data to compare the rates of dementia among players who played high-level rugby in New Zealand between 1950 and 1970 and those who did not.
"We are well aware that much has changed over the past 40 years," a NZ Rugby spokesman said at the time. "The public awareness of concussion, the way concussion injuries are managed, and the nature of rugby itself have all changed dramatically since those players who have dementia now last played."