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Item new Peer-reviewed Added

Australians in same-sex relationships had about a quarter higher all-cause mortality

Australian census records linked to death registrations show all-cause mortality a quarter higher among adults in same-sex than different-sex relationships, and external-cause mortality two to three times higher.

Census records linked to death registrations followed 54,529 adults in same-sex relationships and 7.9 million in different-sex relationships from 2011 to 2023. All-cause mortality was about a quarter higher for women and men in same-sex relationships, at hazard ratios of 1.25 and 1.24. External-cause mortality carried hazard ratios of 2.56 for women and 1.96 for men, and remained elevated both before and after the 2017 marriage reform.

Why it is interesting: A whole-population mortality estimate for a group national statistics cannot identify, resting on relationship status as the proxy.

Source
American journal of public health, 17 September 2026
Paper
All-Cause and External-Cause Mortality Disparities Among Australians in Same-Sex Relationships Before and After Marriage Equality: A Nationwide Cohort Study, 2011-2023
Authors
Saxby K
DOI
10.2105/ajph.2026.308712
Type
Peer-reviewed article
Design
Census-linked national cohort, 54,529 adults in same-sex vs 7,923,328 in different-sex relationships, Cox models with inverse probability weighting, 2011-2023
Verdict
New finding
Driver
What linked data reveals

Other drivers in Data, models and systems