Overview

• Researchers analyzed almost 13,000 men who played provincial level or higher between 1950 and 2000 against 2.4 million matched New Zealand men using records from 1988 to 2023.
• Former players recorded 65 neurodegenerative diagnoses or deaths per 1,000 versus 52 per 1,000 in the general population, reflecting a 22% relative increase.
• The excess risk typically emerged from about age 70 with no evidence of earlier-onset illness in the player cohort.
• Risks were greater for internationals or professionals than provincials, with backline players showing further increases linked to longer careers and more matches.
• The authors recommend limiting head-impact exposure and proactive concussion management, and the peer-reviewed paper appears in Sports Medicine with data access via Statistics New Zealand’s IDI and support from World Rugby and the New Zealand Rugby Foundation.