Overseas researchers looked at 412 Scottish former international rugby union players and compared them to more than 1200 people from the general public. The exact risk among the former athletes varied by each condition, ranging from just over twice as high for dementia to up to 15 times as high for motor neurone disease.
This is a companion discussion topic for the original entry at https://www.sciencemediacentre.co.nz/2022/10/05/brain-disease-risk-more-than-double-among-former-rugby-players-expert-reaction/