Rugby stars Shane Williams and Ben Kay sign up for research into dementia links with sport

Former rugby stars Shane Williams and Ben Kay are to join Alan Shearer in lending their weight to the fight against dementia.

Wales' record try scorer Williams and World Cup-winning England lock Kay are among 50 elite ex-players to have signed up for the Alzheimer's Society-funded PREVENT:RFC project, which forms part of the Sport United Against Dementia campaign.

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In addition, former England football captain Shearer, who presented the BBC documentary, Alan Shearer: Dementia, Football and Me which investigated the link between the game and brain injury, is one of those taking part in an informal pilot study.

Shearer said: "I've been following the sport and dementia conversation for years now - and there's still more I want to learn about the science behind the stories in the news.

"I know the risk of dementia is something that worries many players, so work directed to understanding the earliest stage of dementia is incredibly important, and this study in rugby players will add to our understanding of that in sport."

The risk of brain injury in footballers has been highlighted in recent years by the deaths of England 1966 World Cup winners Ray Wilson, Martin Peters, Nobby Stiles and Jack Charlton, who had all been living with dementia, and in particular former West Brom striker Jeff Astle, whose daughter Dawn has campaigned for action to address the issue.

Research has suggested that footballers are up to five times more likely to die from Alzheimer's disease than the general public.

In rugby too, there has been mounting concern with former England hooker Steve Thompson and ex-Wales international Alix Popham among a group of ex-players exploring legal action for alleged negligence against the game's authorities.

Kay said: "It was really important to me as a rugby player to take part in this study. There has been a lot of media coverage around this topic lately and as a result, I know lots of players are worried about their dementia risk.

"Hopefully, by doing this research now, we can get a better understanding of this issue and make a real difference for the future."

Forecasts suggest the number of people with dementia in the United Kingdom will rise to one million by 2025, and 700 volunteers are already involved in the UK and Ireland-wide PREVENT research project, under which they will be assessed via physical health checks, brain scans, memory assessments, lifestyle questionnaires and sample collections over a two-year period.

PREVENT:RFC, which is backed by an additional £250,000 from the Alzheimer's Society, is one strand of the Sport United Against Dementia campaign, seeking to improve the lives of current and former players and fans and will be based in Edinburgh under the charge of principal investigator Professor Craig Ritchie, who will work alongside Professor Willie Stewart from the University of Glasgow.

Professor Stewart said: "It is vitally important we better understand the links between sports such as football and rugby and dementia, so we can better protect players from any risks they may face.

"Previous research led by our team at the University of Glasgow demonstrated the increased risk of neurodegenerative disease in former professional football players.

"I am delighted to be a part of this latest PREVENT study into professional rugby players, and the adjoining pilot looking at professional football players, so we can bring more insight to this important research area."