No overall link between concussion, length of career and cognitive function in retired male elite rugby union players aged 50+
PRESS RELEASE ISSUED BY LSHTM
New study finds worse cognitive function in players aged 75+ with a history of multiple concussions
Retired male elite rugby union players aged 50+ who suffered three or more rugby-related concussions during their career have no worse average cognitive function than those who had experienced no, one or two concussions, according to a new study in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
The BRAIN study – funded by The Drake Foundation – worked with nearly 150 retired elite players now aged 50+ who played for either England, Oxford University or Cambridge University in the pre-professional era1.
Although no worsening of cognitive function was seen in the group overall and in the under 75s, the study found that over 75s who had suffered three or more rugby-related concussions during their career (14/48) had significantly worse cognitive function on average than those who had experienced no, one or two concussions, and may be at greater risk of more problems in the future, such as memory loss.
The research team says the findings have implications for the clinical management of older ex-rugby players, and possibly ex-players of other contact sports who may be at increased risk of impaired cognitive function affecting mental abilities such as memory and cognition. The team says that the findings are reassuring for those under 75 years, but there are significant differences for those over age 75 years.
Given the age of the participants, these findings therefore primarily relate to the pre-professional era in rugby. Further research is needed into those who have played the game more recently, particularly when they reach the older age groups where cognitive problems are more common.
The BRAIN study is the first to carry out detailed measurements of cognitive function in a large number of former players and to relate this to their concussion and playing history. It was conducted by the London School of Hygiene & Tropical Medicine, Queen Mary University of London and the Institute of Occupational Medicine with researchers from UCL and the University of Oxford, and with assistance from the Rugby Football Union (RFU). It is also the first to include substantial numbers from the over-75 age-group. Previous studies which have focussed on younger players have found little or no association between concussions and reduced cognitive function.
Professor Neil Pearce from the London School of Hygiene & Tropical Medicine, one of the Principal Investigators and study last author, said: “Evidence is accumulating on the possible long-term health risks in former contact sport athletes. However, each sport is different and there is currently little evidence from rugby players. This study adds to this knowledge gap, and shows that playing elite rugby may affect cognitive function in older age. It’s important more research is conducted to confirm this, and on those who played in the early years of professional rugby.”
The research team suggests that a possible reason that the lower cognitive function was only noticeable in those over 75, may be at least in part due to the fact the former elite rugby players in this study were generally highly educated and likely had higher than average cognitive function at the start of their playing careers.
Dr Valentina Gallo, from the University of Groningen in the Netherlands (formerly at Queen Mary University of London), another of the Principal Investigators of the BRAIN study, and study first author, said: “Our findings are in line with those of previous studies, and perhaps highlight that the high cognitive reserve in this study group may have masked the initial phases of any cognitive problems they experience. We’ll be following up on this group of players to shed further light on our findings.”
To examine brain health trends, participants took part in an extensive set of tests capturing physical and cognitive capabilities. Participants cognitive function was measured using the Pre-clinical Alzheimer Cognitive Composite (PACC) score, which combines tests that assess episodic memory, timed executive function, and global cognition2.
After adjusting for a large number of potential confounding factors including age, smoking and player playing position, participants over 75 with three or more concussions scored about two points lower on the PACC score. This does not indicate clinical disease; rather it indicates a difference in cognitive function that can only be detectable with this sort of detailed testing, but which may indicate an increased risk of eventually developing neuro-degenerative conditions such as Alzheimer’s disease.
A total of 116 (80%) respondents reported at least one rugby-related concussion. Among the concussed, the number of rugby-related concussion ranged between one and 25, with a median of two. The number of rugby-related concussions was not associated with the position they played or with length of rugby career.
Dr Simon Kemp, RFU Medical Services Director, said: “This study, that started in 2017, adds to our developing understanding of the potential long term consequences of head impacts and concussions. The agreed group of participants were aged 50+ principally because of the greater likelihood that we might detect any neurocognitive decline if present. It is important to also conduct research with younger retired players.
“A new research programme launched with Premiership Rugby and two independent experts will run alongside the Advanced Brain Health Clinic opening in London on 25 October. This specialist clinical service will provide the assessment and management of retired elite male and female rugby players between the ages of 30-55 who have concerns over their individual brain health.”
Lauren Pulling, CEO of The Drake Foundation, said: “These are interesting results that provide new insights into the long-term effects of rugby as it was played in the pre-professional era, given that a difference in cognitive function was not seen until players were aged over 75. The findings also raise questions about how these effects might differ compared with players from today’s game, particularly given the players coming forward with early-onset neurodegenerative diseases following participation in modern rugby union. The Drake Foundation would like to thank the research team and all the ex-players who took part in this important study.”
The authors acknowledge limitations of the study. These include the fact, that as in all cross sectional studies of retired players, it relied on participants self-reporting how many concussions they had experienced. This was minimised by using a standardised tool (Brain tool). The choice of the cognitive assessment tool is also key. It is possible that the PACC, despite its recognised ability to capture early changes in cognitive function, may not have been sensitive enough to detect subtle cognitive changes in highly educated people engaged in mostly executive jobs.
For interviews with LSHTM’s Professor Neil Pearce please contact [email protected].
For interviews with RFU’s Dr Simon Kemp please contact Verity Williams – [email protected]
A copy of the embargoed paper is available upon request.
Link to paper for stories once live https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/alz.12455
Notes for Editors
Valentina Gallo, Damien M. McElvenny, Giulia Seghezzo, Simon Kemp, Elizabeth Williamson, Kirsty Lu, Saba Mian, Laura James, Catherine Hobbs, Donna Davoren, Nigel Arden, Madeline Davies, Andrea Malaspina, Michael Loosemore, Keith Stokes, Matthew Cross, Sebastian Crutch, Henrik Zetterberg, Neil Pearce. Concussion and long-term cognitive function among rugby players—The BRAIN Study. Alzheimer’s & Dementia. DOI: 10.1002/alz.12455.
1 Former elite male rugby union players aged 50+ years were recruited from two sources: former Oxford/Cambridge University players previously recruited in a study conducted in the Centre for Sport, Exercise and Osteoarthritis Research Versus Arthritis at the University of Oxford and all individuals listed on the England Rugby Internationals Club (ERIC) database—an organization of current and former England international players.
2The primary outcome measure for this study was an adapted version of the Alzheimer Disease Cooperative Study – Preclinical Alzheimer Cognitive Composite (PACC). The PACC comprises a series of tests to capture measures of cognitive function, including episodic memory, timed executive function and global cognition. This series of tests is known to be a useful tool in detecting characteristics of cognitive function that have previously been shown to be most sensitive to change in people in the pre-clinical stages of neurodegenerative disease, or in at-risk populations. In other words, the PACC can be used as a tool to detect early signs of cognitive problems in people with risk factors for Alzheimer’s disease, but who do not show any clinically significant symptoms of mild cognitive impairment or Alzheimer’s disease itself. A low PACC score does not indicate that a person will develop dementia, rather it means that they may have a higher risk than average.
About the London School of Hygiene and Tropical Medicine
The London School of Hygiene & Tropical Medicine (LSHTM) is a world-leading centre for research, postgraduate studies and continuing education in public and global health. LSHTM has a strong international presence with over 3,500 staff and 5,000 students working in the UK and countries around the world, and an annual research income of £180 million. LSHTM is one of the highest-rated research institutions in the UK, is partnered with two MRC University Units in The Gambia and Uganda, and was named University of the Year in the Times Higher Education Awards 2016. Our mission is to improve health and health equity in the UK and worldwide; working in partnership to achieve excellence in public and global health research, education and translation of knowledge into policy and practice.
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About the Institute of Occupational Medicine
The Institute of Occupational Medicine (IOM) protects people across the world by working to create safe environments. Building on our 50-year history, IOM uses multi-disciplinary teams to investigate and solve environmental challenges across workplaces, homes and the wider environment. Through our independent research, a UKAS accredited laboratory and experienced ventilation testers, occupational hygienists and authorising engineers, our mission is to make the world a healthier, safer and more sustainable place.
IOM Research is a core part of that, providing authoritative evidence-based research, which informs policy, regulation and practice. Contributing to over 2,750 articles and speaking at national and international conferences, our experts are well respected and sought after. Our work is also applied to industry, working with partners such as NHS Scotland and EU-OSHA we support the application of science for the betterment of society.
About The Drake Foundation
The Drake Foundation is a not-for-profit organisation committed to understanding and improving the health and welfare of people impacted by head injuries, including sports players and IPV (intimate partner violence) survivors, through scientific research and collaboration.
Founded in 2014 by James Drake, the Foundation has since invested more than £2.2 million into research funding and open access resources.
The majority of this funding to date has gone into research into sport-related head injuries and long-term health outcomes, with the objective of making sport safer and providing valuable insights into the processes underlying neurogenerative diseases, such as dementia. In 2021, the Foundation expanded its portfolio to include research into brain injury from IPV.
Amongst the projects that The Drake Foundation funds are the HEADING study, which is investigating the link between neurogenerative disease and a professional football career, and the BRAIN study, working with retired rugby players to understand the association between a history of concussion and neurogenerative disease.
For more information on The Drake Foundation’s sports projects, please visit: https://www.drakefoundation.org/our-projects/
About The Rugby Football Union
The Rugby Football Union (RFU) is the National Governing Body for rugby union in England and supports participants and fans from the grassroots to the national team.
For more information visit www.englandrugby.com Keep up to date with all RFU news on @EnglandRugby
About the Advanced Brain Health Clinic
The Advanced BRAIN Health Clinic is a specialist BiomaRker, Advanced Imaging and Neurocognitive assessment clinic for retired elite rugby players.
The Rugby Football Union and Premiership Rugby are collaborating on a partnership with the Institute of Sport, Exercise and Health (ISEH) and Imperial College London to provide a specialist clinical service for the assessment and management of retired elite male and female rugby players between the ages of 30-55 who have concerns over their individual brain health.
The clinic offers a unique, specialist, neurological assessment service, supported by advanced imaging, neurocognitive assessment and biomarker measurements. This will provide retired elite players with a comprehensive assessment of medical and psychological factors relevant to their brain health, led by academic and clinical experts, Professor David Sharp and Dr Richard Sylvester.
For more information visit: https://iseh.co.uk/patients/clinical-services/advanced-brain-health-clinic-london