A major University of Auckland-led study examining the long-term brain health of former high-level male rugby players in New Zealand has found higher rates of neurodegenerative disease compared to the general population.
It also found that the higher the level ofrugby played, the higher the risk of brain disorder.
The study, published today in Sports Medicine, is part of Kumanu Tāngata: The Aftermatch Project, designed to explore the long-term health and social outcomes for high-level male rugby players.
New Zealand Rugby (NZR) and the New Zealand Rugby Foundation said they welcomed its release.
Researchers analysed the health records of 12,861 men who played at provincial level or higher between 1950 and 2000, comparing them with 2.39 million men from the general population matched by age, ethnicity and birthplace.
The risks were higher for backline players, those with longer careers, and those who played more matches.
The research found no evidence of higher rates of these conditions, such as Alzheimer’s, appearing earlier in life. Players who developed them typically showed symptoms between the ages of 70 and 79.
NZR chief executive Mark Robinson, who played nine tests for the All Blacks, said the research was a vital step forward in the organisation’s player welfare work, particularly around brain health and concussion.
“Having played the game at the highest level, I understand the demands rugby places on our players - that’s why player welfare isn’t just a priority for me, it’s personal. These results will be concerning for some people. While we can’t change the past, we acknowledge the impact rugby has had on some players and their whānau.
“Their experiences matter deeply, and they continue to guide the work we’re doing to improve player welfare and drive meaningful change across the game.”
The organisation said the findings provided a strong evidence base for NZR to keep improving player safety in line with the latest evidence, and ensuring all players had access to clear information to make informed decisions about their health. NZR said this included “supporting former players affected by neurodegenerative conditions”.
The funeral service of Shane Christie in Nelson earlier this week. Photo / RNZ, Samantha Gee
Last week, former Tasman Mako captain, Māori All Black and Highlanders Super Rugby flanker Shane Christie suddenly died at the age of 39.
Christie retired from professional rugby in 2017 because of severe post-concussion symptoms and became a passionate advocate for the better understanding and prevention of brain injuries in the sport. He spoke publicly about his belief that he was suffering from chronic traumatic encephalopathy (CTE), which is linked to repeated head trauma.
NZR acknowledged his death, saying, “Our thoughts remain with his whānau, friends and former teammates at this difficult time.
“The release of this research was planned in co-ordination with our partners and the Sports Medicine journal. We believe it is important to proceed in an open and transparent way, ensuring the findings are shared to support greater understanding and ongoing improvements in player safety and wellbeing."
While the study provided robust evidence of an association between high-level rugby participation and later-life neurodevelopmental disorder (NDD) risk, the findings did not include women, lower-level players, or those whose careers began after 2000.
NZR said the way the game was played had changed since then, with player welfare the driving factor. Stricter tackle laws, safer scrum techniques and enhanced medical protocols have all been introduced to reduce concussion risks and support long-term brain health.
NZ Rugby chairman David Kirk told RNZ’s Nine to Noon that the results of the study were worrying.
“We don’t want anyone to be exposed to situations where they will have a higher incidence or likelihood of neurodegenerative disease because they played the game, but those are the facts.”
Kirk chaired the New Zealand Rugby Players’ Association (NZRPA) for 25 years before becoming chairman of NZR in 2024.
He believed the sport was doing all it could to support its former elite players.
“I know that the players’ association does a great deal hand-in-hand with New Zealand Rugby, and probably the players’ association does more when players have retired.
“Any professional player remains a member of the NZ Rugby Players’ Association when they retire, and there is a lot of support for them. So I think the answer is yes, it’s not to say we can’t do more, but a great deal is done for players.
“There’s a lot of engagement with them in all sorts of different ways [from the players’ association] and their health and wellbeing and their support for a whole range of players and their families, if they find themselves in difficult financial or medical circumstances, is extensive and I feel very pleased and proud of that.”
In March this year, NZR, the players’ association and the NZ Rugby Foundation launched an enhanced Brain Health and Concussion Risk Management Plan. Key elements include law changes to reduce high-impact contact, improved head injury assessment (HIA) protocols, and better access to specialist medical support. Concussion awareness programmes are also being rolled out across all levels of the game.
Rugby Foundation chief executive Lisa Kingi-Bon said Kumanu Tāngata reflected its ongoing commitment to supporting players beyond their time on the field.
Former player Shane Christie's shirt was displayed during the Tasman Makos' NPC game against Otago last Saturday. Photo / Chris Symes, Photosport
“The brain health and concussion plan builds on this by focusing on long-term wellbeing, informed care, and culturally responsive approaches. Together, these initiatives aim to strengthen how we support players throughout their journey.”
The three organisations say they remain committed to updating safety measures in line with the latest evidence, supporting former players affected by neurodegenerative conditions, and ensuring all players have access to clear, accessible information to make informed decisions about their health.
Kumanu Tāngata was funded and facilitated by World Rugby, the NZ Rugby Foundation, NZR, Stats NZ and the University of Auckland Public Policy Institute.
This was the first published study from the project. Future research will explore broader health outcomes and the long-term benefits of playing rugby.