Differences in characteristics, treatments and outcomes in patients with non-ST-elevation myocardial infarction: novel insights from four national European continuous real-world registries

Aims: To study baseline characteristics, in-hospital managements and mortality of non-ST-elevation myocardial infarction (NSTEMI) patients in different European countries.

Methods and results: NSTEMI patients enrolled in the national myocardial infarction (MI) registries [EMIR; n = 5817 (Estonia), HUMIR; n = 30 787 (Hungary), NORMI; n = 33 054 (Norway), and SWEDEHEART; n = 49 533 (Sweden)] from 2014 to 2017 were included and presented as aggregated data. The median age at admission ranged from 70 to 75 years. Current smoking status was numerically higher in Norway (24%), Estonia (22%), and Hungary (19%), as compared to Sweden (17%). Patients in Hungary had a high rate of diabetes mellitus (37%) and hypertension (84%). The proportion of performed coronary angiographies (58% vs. 75%) and percutaneous coronary interventions (38% vs. 56%), differed most between Norway and Hungary. Prescription of dual antiplatelet therapy at hospital discharge ranged from 60% (Estonia) to 81% (Hungary). In-hospital death ranged from 3.5% (Sweden) to 9% (Estonia). The crude mortality rate at 1 month was 12% in Norway and 5% in Sweden (5%), whereas the 1-year mortality rates were similar (20-23%) in Hungary, Estonia, and Norway and 15% in Sweden.

Conclusion: Cross-comparisons of four national European MI registries provide important data on differences in risk factors and treatment regiments that may explain some of the observed differences in death rates. A unified European continuous MI registry could be an option to better understand how implementation of guideline-recommended therapy can be used to reduce the burden of cardiovascular disease.