A Rorschach test for rugby: contrasting conclusions from new dementia study

Two press releases arrive two hours apart, offering two very different views of the same new study published on Wednesday in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. It is called the BRAIN study, it was led by a team of researchers at the London School of Hygiene and Tropical Medicine, supported by the Rugby Football Union, and funded by an independent body called the Drake Foundation. It was designed to look at cognitive function in a group of 146 elite rugby players from the amateur era, all aged over 50, and, as the headline on the first release said, it found “no overall link between concussion, length of career, and cognitive function”.

In short, it was broadly reassuring. Until you read on. Because the study also found what seems to be a very clear link among one sub-group of the 146. Among players aged 75 and over, those who had suffered three or more rugby-related concussions were found to have significantly worse cognitive function. That doesn’t mean they will necessarily develop dementia, but it does mean that they are likely at higher risk of it. “If our findings are correct,” says lead author Prof Neil Pearce, players in their 50s now ”might start to see a problem when they reach 75”.

Related: Damning report on head injuries in sport seen as ‘turning point’

So there’s a certain tension between the study’s primary and secondary findings. Which means that exactly how “reassuring” you find it depends on your age, and your ideas about acceptable risk. And that’s before you get into the complicating factors. The majority of the players (113) were former Oxbridge Blues (because the researchers had access to a group who had already signed up for previous trials) and the rest (33) were former England internationals. It’s possible that the Oxbridge group may have what is called a “high cognitive reserve”, which means any change in cognitive function is delayed until older age. “It’s very speculative,” says Pearce, “but it can’t be ruled out.”

It’s also true that the study had no good way of calculating the number of sub-concussive blows these players suffered. Instead they used players’ career duration as a proxy measure. All of which means the report feels like a sort of Rorschach test. “The science is the science,” says the RFU’s director of medical services, Simon Kemp, but its significance is a question of interpretation. Which brings us back to those two press releases. Because – and this is where it gets really knotty – two of the groups who collaborated on the study disagree about what it means for the sport.

For the RFU, who co-signed the first release, the study is a sign that “more research needs to be done” looking at people who played in the professional era. This is already under way. The RFU is working on it with the Advanced Brain Health clinic and Premiership rugby. Kemp says that until that second study is completed, it’s impossible to say what the BRAIN study means, if anything, for people playing the game today given the differences between the amateur and professional era. “Commenting on relative risk is problematic, we would want to focus on the risk in the study that we have completed, have had peer reviewed, and have had published.”

The Drake Foundation disagree. They co-signed the first press release too. Then they issued another of their own. And if the tone of the first was broadly reassuring, the tone of the second was profoundly alarming. The Foundation believe that when you look at the BRAIN study in the context of existing research on the professional rugby era, it suggests the game may have been safer in the pre-professional era. Their own Drake Biomarker study published earlier this year showed that almost one in four players studied had abnormal changes to their brain structure, and one in two had unexpected reductions in white matter volume. The Foundation are now “urging rugby authorities and governing bodies to consider immediate law changes to the sport at all levels”.

A World Rugby spokesman says those changes are “already under way” in current law trials “such as the 50:22, goal-line drop out, and breakdown amendments, which are all aimed at reducing head injury risk, and lowered tackle height at a domestic level. This is in addition to robust protocols such as the Head Injury Assessment and Graduated Return to Play process, increasing research investment and embracing of new technology such as eye tracking and instrumented mouthguards.”

“We are definitely encouraged by the action they are taking, but what we would say at the minute is that those are recommendations rather than enforceable law changes,” says Drake’s chief executive, Lauren Pulling. “Clearly we don’t have the full picture here, but the mixture of scientific evidence and anecdotal evidence suggests that the sport may be travelling in the wrong direction.”

The Drake Foundation isn’t in the business of editorialising. “Until now we’ve not put out opinions on anything we do, we’ve purely funded research,” Pulling says. “However we now believe we are at a critical point and that, although there are gaps in the research, there are enough indicators to show that players are sustaining long-term negative health effects from repeated head impacts in sport. We’re not campaigners, we fund research to build the evidence base, and we believe that that base has got to the point where we need to see substantial change to protect players. We think we could see another generation of players suffering the same sorts of issues if we don’t take more preventative action.”

So on the one side, there’s a call for more research, on the other, there’s a call for more action, and in the middle are the players, weighing risks that the experts can’t agree on.