ST-elevation myocardial infarction in a migrant population : a registry-based study of patient treatment and outcomes

Background: Internationally, a growing number of studies has identified race-related disparities in the presentation, treatment and outcomes of patients with ST-elevation myocardial infarction (STEMI). With a large migrant population, Australia presents a unique microcosm in which to study the impact of migrant status and ethnicity in STEMI patients. Aim: To investigate if first-generation migrants differed in presentation, treatment or outcomes following STEMI compared with the Australian-born population. Methods: We conducted a retrospective observational study using data from a clinician-initiated registry. The study involved 2154 patients who presented to 12 hospitals between 2004 and 2012. Our main outcome measures included time to reperfusion, 30-day mortality and complications. Results: Migrants (n = 1035, 48.8%) were more likely to be older (61 vs 58 years, P < 0.001), diabetic (29.3 vs 21.5%, P < 0.001) and have a prolonged symptom to door time (102 vs 91 min, P = 0.04). Despite lower rates of previous known ischaemic heart disease (22.5 vs 26.6%, P = 0.03), migrants had more diffuse disease (triple vessel or left main (3VD/LM): 29.8 vs 22.0%, P < 0.001) and higher troponin values (3.77 vs 3.22 μg/L, P = 0.01). We found no significant differences in hospital treatment times, intervention types or rates. Multivariate regression identified age, diabetes, female gender and multi-vessel disease as predictors of complications and death at 30 days. Conclusions: Migrants had longer pre-hospital delays and exhibited different cardiovascular risk profiles than Australian-born patients but received comparable treatment in the acute hospital setting. Higher rates of diabetes and multi-vessel coronary artery disease were seen among migrant patients, indicating a relatively higher risk population.