Background: Cardiovascular disease, particularly acute coronary syndromes (ACS), is the leading cause of death in the United States. Minor fluctuations in hospital admissions for different conditions, including ACS, can be seen throughout the year. This study focuses on the impact of admission month on outcomes of acute coronary syndromes during the first year of the COVID-19 pandemic.
Methods: This was a retrospective observational study of patients hospitalized with ACS from the National Inpatient Sample, during the years 2020 (n = 779,895) and 2019 (n = 935,975). We compared the monthly outcomes for every month to the outcomes for the month of January of that same year. The primary outcomes of interest were in-hospital mortality and time from admission to PCI.
Results: Inpatient mortality for patients admitted with STEMI was significantly higher for admissions in the months of April, October and December of 2020 than January of that same year. For patients admitted with NSTEMI or UA, inpatient mortality was higher for admissions in April and December 2020 when compared to admissions in January 2020. Inpatient mortality for patients with STEMI, NSTEMI and UA was not different based on admission month in the year 2019.
Conclusion: The month of admission significantly affected outcomes for patients admitted with ACS during the COVID-19 pandemic, with higher inpatient mortality and longer time from admission to PCI for certain months in 2020. Further studies should investigate disparities in monthly ACS outcomes for the year 2021 and onward, now that COVID-19 infections have been steadily declining.
Keywords: ACS; PCI; STEMI; admission month.