Long-term mortality, cardiovascular events, and bleeding in stable patients 1 year after myocardial infarction: a Danish nationwide study

Outcomes after myocardial infarction (MI) improved during recent decades alongside better risk factor management and implementation of guideline-recommended treatments. However, it is unknown whether this applies to stable patients who are event-free 1 year after MI.

Using nationwide Danish registries, we included all patients with first-time MI during 2000-17 who survived 1 year free from bleeding and cardiovascular events (n = 82 108, median age 64 years, 68.2% male). Follow-up started 1 year after MI and continued through January 2022. Crude risks of mortality, cardiovascular events, and bleeding were estimated in consecutive 3-year periods. Standardized risks were calculated with respect to the distribution of age, sex, comorbidities, and treatments in the latter period. Guideline-recommended treatment use increased during the study period: e.g. statins (68.6-92.5%) and percutaneous coronary intervention (23.9-68.2%). The crude 5-year risks of outcomes decreased (all P-trend <0.001): Mortality, 18.6% (95% confidence interval [CI]: 17.9-19.2) to 12.5% (CI: 11.9-13.1); Recurrent MI, 7.5% (CI: 7.1-8.0) to 5.5% (CI: 5.1-6.0); Bleeding, 3.9% (CI: 3.6-4.3) to 2.7% (CI: 2.4-3.0). Crude 5-year risk of mortality in 2015-17 was as low as 2.6% for patients aged <60 years. Use of guideline-recommended treatments was associated with improved outcomes: After standardization for changes in treatments, 5-year risk of mortality in 2000-02 was 15.5% (CI: 14.9-16.2).

For patients who were event-free 1 year after MI, the long-term risks of mortality, cardiovascular events, and bleeding decreased significantly, along with an improved use of guideline-recommended treatments between 2000 and 2017. In the most recent period, 1 year after MI, the risk of additional events was lower than previously reported.