30-year trends in incidence of acute STEMI and NSTEMI in the Belgian Province of Luxembourg. A long-term follow-up of the MONICA-BELLUX registry.

Background: We sought to evaluate the temporal changes in the incidence of acute myocardial infarction (AMI) using a 30-year continuation of the WHO MONICA registry in Luxembourg, applying modern MI definitions (STEMI and NSTEMI).

Methods: We reanalysed clinical records, biomarkers, ECGs, and angiograms of all suspected Type I and III AMI cases from 1985 to 2014 in the MONICA-BELLUX registry. Cases were classified according to modern criteria as STEMI, NSTEMI, or ischaemic sudden cardiac death. Statistical analyses assessed trends in AMI incidence by sex, age group, and AMI type.

Results: A total of 6,786 AMI cases were identified, including 4,361 STEMI, 1,507 NSTEMI confirmed by coronary thrombosis, 616 suspected NSTEMI, and 394 type III infarcts. The overall AMI incidence decreased by 5.3 events per 100,000 inhabitants annually, from 314 per 100,000 in 1986 to 116 per 100,000 in 2014. This decline was driven mainly by a 3.8-fold reduction in STEMI. NSTEMI incidence initially decreased, then stabilised after 2004, with the STEMI-to-NSTEMI ratio converging by 2009. While women had 3.8 times lower incidence of AMI, trends were similar across both sexes and all age groups. Survival rates, lower in women and NSTEMI, improved with increased use of coronary angiography and revascularization.

Conclusion: Over 30 years, AMI incidence, particularly STEMI, decreased threefold across all age groups and genders, while NSTEMI incidence initially declined but increased after 2000 due to improved diagnostic sensitivity with troponins, and survival rates improved with greater use of angiography and revascularization.