All-cause and cause-specific mortality among transgender and gender diverse people: a nationwide cohort study in Australia.

Abstract

Transgender and gender diverse ('trans') people may be at increased risk of mortality, particularly from external causes, however, large-scale, population-based evidence remains scarce. This study aims to document all-cause and cause-specific mortality among trans people. We source administrative data on healthcare and death records (2012-2023) from all Australians aged 15 years and above. Individuals identified as trans (initiated gender-affirming hormone therapy) were matched to the general population who visited a General Practitioner during the same period. Cox proportional hazard models were used to estimate all-cause and cause-specific mortality risk for trans people, with models estimated separately for people who were assigned female sex at birth (AFAB) and people who were assigned male sex at birth (AMAB). Inverse probability weights were applied to balance comparators on month-year and age at entry. Results were additionally stratified by age (15-24, 25-39, 40-59, and ≥60 years). A total of 19,347 trans people AMAB (mean age 36.2 years; median follow-up 3.7 years) and 9713 trans people AFAB (mean age 25.4 years; median follow-up 2.8 years) were matched with 9,879,037 general population males (mean age 44.4; median follow-up 11.3 years) and 10,282,651 general population females (mean age 44.9; median follow-up 11.4 years), respectively. All-cause mortality was significantly higher for trans people AMAB [HR = 3.89 (95% CI 33.65; 4.14)] and trans people AFAB [HR = 9.03 (95% CI 6.90; 11.83)]. For trans people AFAB, cause-specific mortality was elevated for cardiovascular disease [HR = 16.39 (95% CI 8.56; 31.37)], suicide [HR = 11.73 (95% CI 6.94; 19.80)], external causes [HR = 8.95 (95% CI 5.69; 14.09)], and cancer [HR = 7.62 (95% CI 4.61; 12.61)]. For trans people AMAB, cause-specific mortality was elevated for cancer [HR = 5.12 (95% CI 4.67; 5.61)], suicide [HR = 4.02 (95% CI 3.12; 5.18)], external causes [HR = 2.78 (95% CI 2.31; 3.35)], and cardiovascular disease [HR = 2.60 (95% CI 2.22; 3.05)]. Older trans people had more pronounced excess risk from cancer and cardiovascular disease. For trans people AFAB, excess mortality from suicide and external causes increased with age, whereas for trans people AMAB relative risks were higher in young and middle adulthood. In this nationwide cohort study, trans Australians experienced substantially elevated mortality risk. Tailored policy responses are needed to address premature mortality in trans populations. University of Melbourne McKenzie Fellowship (2025MCK182); the National Health and Medical Research Council (2008956); Viertel Charitable Foundation; University of Melbourne Faculty Research Grant (2025FRG19).