Sex differences in management and outcomes of people with ST-elevation myocardial infarction, New South Wales, 2011–2020: a retrospective cohort study

Abstract

Objectives: To examine whether sex differences in cardiovascular disease care and outcomes for people hospitalised with ST-elevation myocardial infarction (STEMI) in New South Wales have declined during 2011–2020. Study design: Retrospective cohort study; analysis of linked New South Wales Admitted Patient Data Collection and Registry of Births, Deaths and Marriages data. Setting, participants: Adults (18 years or older) admitted to public or private hospitals in New South Wales with STEMI for the first time during 1 January 2011 – 31 December 2020. Major outcome measures: Proportions of people who received coronary angiography or percutaneous coronary intervention (PCI) within seven days of first STEMI admission, by year and sex; proportions of STEMI admissions followed by major adverse cardiovascular events (MACE) or death (any cause) within twelve months, by year and sex; rate of change in these parameters, adjusted for age group, intensive care unit admission, and Charlson Comorbidity Index score. Results: We identified 29 435 initial STEMI hospital admissions during 2011–2020; the mean age at admission was 66.1 years (standard deviation, 14.2 years), 8475 patients were women (28.8%) and 20 960 were men (71.2%). The proportions of female patients who underwent angiography (71.9% v 85.1%) or PCI (54.4% v 70.0%) were smaller than those of male patients. During 2011–2020, the increase in the angiography proportion was greater for female than for male patients (2.7 [95% confidence interval {CI}, 2.5–2.9] v 1.5 [95% CI, 1.4–1.6] percentage points per year), as was the change in PCI proportion (3.2 [95% CI, 2.9–3.6] v 2.5 [95% CI, 2.3–2.7] percentage points per year). The proportions of admissions followed by MACE (18.4% v 15.0%) or death of any cause (14.7% v 8.5%) were larger for female than male patients. The decline in the MACE proportion during 2011–2020 was similar for female and male patients (0.8 [95% CI, 0.5–1.1] v 0.5 [95% CI, 0.3–0.7] percentage points per year); the decline in all-cause mortality was greater for female than male patients (1.0 [95% CI, 0.8–1.1] v 0.6 [95% CI, 0.5–0.7] percentage points per year). Conclusion: The increase in the proportions of patients with STEMI who underwent timely angiography and PCI was more rapid during 2011–2020 for female than male patients, and the decline in all-cause mortality was also greater. Sex differences in treatment and outcomes for people with STEMI are declining but will not be eliminated during the next ten years.