Cardiovascular and all-cause mortality following acute coronary syndromes in mental health service users.

BACKGROUND: People with mental health (MH) conditions experience increased rates of acute coronary syndromes (ACS) and post-ACS mortality. The contribution of cardiac and other causes to excess mortality is unclear. METHODS: Using linked data, we identified all ACS admissions in New South Wales (NSW), Australia, from 2017 to 2021, and people with acute or severe mental illness using state-operated MH services. We examined 30-day and 12-month cardiovascular and all-cause mortality, and cardiovascular complications using binary logistic and competing-risks regressions, adjusting for demographics, socioeconomic disadvantage, comorbidities, ACS type and revascularisation. Subgroup analyses examined age, Indigenous Australians and severe or persistent mental illness. RESULTS: Of 65,814 ACS admissions, 4 % occurred in MH service users. MH service users had increased 30-day (all-cause OR 1.70, 95 %CI 1.46-1.97; cardiovascular-specific OR 1.60, 95 %CI 1.31-1.96) and 12-month mortality (all-cause OR 1.78, 95 %CI 1.59-2.00; cardiovascular-specific OR 1.54, 95 %CI 1.33-1.78). Risks were greater in younger service users and persisted in adjusted regression models. MH service users experienced higher rates of heart failure and stroke but not reinfarction. CONCLUSIONS: Increased all-cause mortality after ACS in MH service users is mainly due to cardiac causes. Strategies should target broad risk factors in the post-hospital period, particularly in younger and Indigenous MH service users.