Surge in Incidence and Coronavirus Disease 2019 Hospital Risk of Death, United States, September 2020 to March 2021.

Background: Studies of the early months of the coronavirus disease 2019 (COVID-19) pandemic indicate that patient outcomes may be adversely affected by surges. However, the impact on in-hospital mortality during the largest surge to date, September 2020-March 2021, has not been studied. This study aimed to determine whether in-hospital mortality was impacted by the community surge of COVID-19. Methods: This is a retrospective cohort study of 416 962 adult COVID-19 patients admitted immediately before or during the surge at 229 US academic and 432 community hospitals in the Vizient Clinical Database. The odds ratios (ORs) of death among hospitalized patients during each phase of the surge was compared with the corresponding odds before the surge and adjusted for demographic, comorbidity, hospital characteristic, length of stay, and complication variables. Results: The unadjusted proportion of deaths among discharged patients was 9% in both the presurge and rising surge stages but rose to 12% during both the peak and declining surge intervals. With the presurge phase defined as the referent, the risk-adjusted ORs (aORs) for the surge periods were rising, 1.14 (1.10-1.19), peak 1.37 (1.32-1.43), and declining, 1.30 (1.25-1.35). The surge rise in-hospital mortality was present in 7 of 9 geographic divisions and greater for community hospitals than for academic centers. Conclusions: These data support public policies aimed at containing pandemic surges and supporting healthcare delivery during surges.