COVID-19 had a significant impact on Emergency Departments (ED) with early data suggesting an initial decline in avoidable ED visits. However, the sustained impact over time is unclear. In this study, we analyzed ED discharges over a two-year time period after the COVID-19 pandemic began and compared it with a control time period pre-pandemic to evaluate the difference in ED visit categories, including total, avoidable, and unavoidable visits.

This was a retrospective, cross-sectional study assessing the distribution of visits with ED discharges from two hospitals within a health system over a three-year time period (1/1/2019–12/31/2021). Visits were categorized using the expanded NYU-EDA algorithm modified to include COVID-19-related visits. Categories included: Emergent - Not Preventable/Avoidable, Emergent – Preventable/Avoidable, Emergent - Primary Care Treatable, Non-Emergent, Mental Health, Alcohol, Substance Abuse, Injury, and COVID-19. Chi-square testing was conducted to investigate differences within the time period before COVID-19 (1/1/2019–12/31/2019) and both initial (1/1/2020–12/31/2020) and delayed (1/1/2021–12/31/2021) COVID-19 time frames and ED visit categories, as well as post hoc testing using Fisher's exact tests with Bonferroni correction. ANOVA with post hoc Bonferroni testing was used to determine differences based on daily census for each ED visit category.

A total of 228,010 ED discharges (Hospital #1 = 126,858; Hospital #2 = 101,152) met our inclusion criteria over the three-year period. There was a significant difference in the distribution of NYU-EDA categories between the two time periods (pre-COVID-19 versus during COVID-19) for the combined hospitals (p < 0.001), Hospital #1 (p < 0.001), and Hospital #2 (p < 0.001). When examining daily ED discharges, there was a decline in all categories from 2019 to 2020 except for “Emergent - Not Preventable/Avoidable” which remained stable and “Substance Abuse” which increased. From 2020 to 2021, there were no differences in ED avoidable visits. However, there were increases in discharged visits related to “Injuries”, “Alcohol”, and “Mental health” and a decrease in “COVID-19”.

Our study identified a sustained decline in discharged avoidable ED visits during the two years following the beginning of the COVID-19 pandemic, which was partially offset by the increase in COVID-19 visits. This work can help inform ED and healthcare systems in resource allocation, hospital staffing, and financial planning during future COVID-19 resurgences and pandemics.