Long-term outcomes after acute myocardial infarction in countries with different socioeconomic environments: an international prospective cohort study

BACKGROUND Hospital-based data on the impact of socioeconomic environment on long-term survival after myocardial infarction (MI) are lacking. We compared outcome and quality of secondary prevention in patients after MI living in three different socioeconomic environments including patients from three tertiary-care teaching hospitals with similar service population size in Switzerland, Poland and Ukraine. METHODS This is a prospective cohort study of patients with a first MI in three different tertiary-care teaching hospitals in Bern (Switzerland), Gdansk (Poland) and Lutsk (Ukraine) during the acute phase in the year 2010 and follow-up of these patients with a questionnaire and, if necessary, telephone interviews 3.5 years after the acute event. The study cohort comprises all consecutive patients hospitalised in every one of the three study centres during the year 2010 for a first MI in the age ≤75 years who survived ≥30 days. RESULTS The proportion of patients with ST-segment elevation myocardial infarction (STEMI) was high in Gdansk (Poland) (80%) and in Lutsk (Ukraine) (74%), while the ratio of STEMIs to non-STEMIs was nearly 50:50 in Bern (Switzerland) (50.6% STEMIs). Percutaneous coronary intervention (PCI) was the first choice therapy both in Bern (Switzerland) (100%) and in Gdansk (Poland) (92%), while it was not performed at all in Lutsk (Ukraine). We found substantial differences in treatment and also in secondary prevention interventions including cardiac rehabilitation. All-cause mortality at 3.5 year follow-up was 4.6% in Bern (Switzerland), 8.5% in Gdansk (Poland) and 14.6% in Lutsk (Ukraine). CONCLUSION Substantial differences in treatment and secondary prevention measures according to low-income, middle-income and high-income socioeconomic situation are associated with a threefold difference in mortality 3.5 years after the acute event. Countries with low socioeconomic environment should increase efforts and be supported to improve care including secondary prevention in particular for MI patients. A greater number of PCIs per million inhabitants itself does not guarantee lower mortality scores.