One year of Covid-19: French nationwide study of hospitalisation, 90-day readmission and mortality rates from myocardial infarction

BACKGROUND: Studies reported a decrease in hospital admissions for myocardial infarction (MI) in early 2020 due to Covid19 crisis, but these were restricted to the early weeks of the pandemic. PURPOSE: To describe patient characteristics, in-hospital management and 90-day mortality of MI patients throughout the year 2020, in particular during periods of lockdowns. METHODS: All patients hospitalised for MI in France from 2017 to 2020 were selected from the national hospital discharge database. Incidence rate ratios were computed to analyze time trends in MI admissions and mortality rates and stratified by type of MI, sex, age, and period of admission. Characteristics and management of patients in 2020 were described and compared to 2017-19 (OR adjusted on temporality, sex, age) RESULTS: In 2020, 94,747 patients were hospitalized for MI corresponding to a 6% decrease in MI admissions compared to 2017-19. This decrease was more significant during the first lockdown (−24%, P < 0.0001), in particular in week 13 (−40%) than during the second lockdown (−8%). Decreases in MI admissions were more pronounced and longer for NSTEMI, older people and for women. An increase in the rate of STEMI admissions was observed between the two 2020 lockdowns (+4%, P = 0.0005). Admission to a resuscitation unit and complications rates did not differ between 2017-19 and 2020. In early 2020, there was also a decrease in 90-days readmission. In 2020, the in-hospital and 90-days-out-of hospital mortality rates were 5.5% and 3.8%, compared to 5.7% and 3.6% in reference years. Globally and after adjustment, mortality rates did not differ in 2020 vs. 2017-19 (IRR(in-hosp) = 1.03[0.98;1.08], P = 0.19 - IRR(out-hosp) = 1.04[0.97;1.27], P = 0.21). CONCLUSIONS: This nationwide study showed significant decrease in MI hospitalization during 2020, in particular during the first lockdown, with a slight STEMI increase during the summer. However, these trends were not associated with more cardiac complications or mortality.