A More Accurate Measurement of COVID-19 Hospitalizations

Abstract

COVID-19 hospitalizations are a key indicator of the SARS-CoV-2 pandemic. The US Centers for Disease Prevention and Control describes oxygen supplementation as a measure of severe disease. SARS-CoV-2 PCR positive patients hospitalized without hypoxia or requiring oxygen may have been identified incidentally due to routine screening practices. We describe the application of a revised case definition for COVID-19 hospitalization based on the case-patient oxygen requirement on admission. Using data collected from consecutive SARS-CoV-2 PCR positive hospital admissions in December 2021 and January 2022 at a large safety net hospital in Los Angeles County, we highlight differences between patients hospitalized with COVID-19 (i.e., no oxygen requirement on admission or `incidental` infection) and those hospitalized for COVID-19 (i.e., oxygen requirement on admission). We conducted multivariable modeling to determine the effect of age as a positive predictor of COVID-19 hospitalization and vaccination or prior infection as a negative predictor. The revised case-definition resulted in a substantial decrease in the number of COVID-19 hospitalizations during the study period: 67.5% of SARS-CoV-2 PCR positive hospital admissions were not for COVID-19 but with COVID-19. A revised case-definition for COVID-19 hospitalization that includes the oxygen requirement on admission is needed to more accurately monitor the pandemic and inform public health policy.

Effectiveness Over Time of a Primary Series of the Original Monovalent COVID-19 Vaccines in Adults in the United States

“…COVID-19 testing capacity and capability have changed rapidly throughout the course of the pandemic, and COVID-19 laboratory testing results were not widely available in the databases utilized for this study, so COVID-19 diagnoses rather than confirmed COVID-19 infections were used as outcomes. COVID-19 severity is not accurately represented in diagnoses, 38 so we evaluated COVID-19 diagnoses overall in any medically attended setting, and separately in hospital/ED settings as a proxy for severity. However, as the pandemic has progressed, COVID-19-related hospitalizations may be the most relevant public health measure for contemporary surveillance and prevention efforts.…”

“…However, as the pandemic has progressed, COVID-19-related hospitalizations may be the most relevant public health measure for contemporary surveillance and prevention efforts. 38,39 We matched vaccination groups on calendar time and evaluated outcomes over calendar time to account for the potentially changing meaning of a COVID-19 diagnosis over time (e.g., care seeking for COVID-19 versus incidental findings).…”