This is a summary, written by members of the CITF Secretariat, of:
McAlister FA, Hau JP, Atzema C, McRae AD, Morrison LJ, Grant L, Cheng I, Rosychuk RJ, Hohl CM; Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) Investigators. The burden of incidental SARS-CoV-2 infections in hospitalized patients across pandemic waves in Canada. Sci Rep. 2023 Apr 24;13(1):6635. doi: https://doi.org/10.1038/s41598-023-33569-2.
The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.
A CITF-funded study, published in Scientific Reports, found that the proportion of incidental SARS-CoV-2 infections increased substantially across the pandemic waves. In particular, the percentage of people who tested positive for COVID-19 upon admission to hospital for something else rose from 10% to 41% during the Omicron wave. This study was led by Dr. Corinne Hohl (University of British Columbia).
This study included data from the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) registry on all SARS-CoV-2 infected patients hospitalized from March 2020-July 2022 in 47 Canadian emergency departments.
- The proportion of people who tested positive for COVID-19 upon admission to hospital for something else rose from 10% in the first wave to 41% during the Omicron wave.
- The study population included individuals with COVID-19 as the “direct cause” for hospitalization (70%), individuals with COVID-19 as a “potential contributing factor” for hospitalization (4%), and individuals with a SARS-CoV-2 infection as an “incidental” finding that did not influence the need for admission (26%).
- Patients with COVID-19 as the direct cause of hospitalization had a significantly longer stay (mean 13.8 versus 12.1 days). They also were more likely to require critical care (22% versus 11%), receive COVID-19-specific therapies (55% versus 19%), and die (17% versus 9%), compared to patients with incidental SARS-CoV-2 infections.
- Compared to patients with COVID-19 as a direct cause of hospitalization, patients with incidental SARS-CoV-2 infections were more likely to be young and less likely to have hypertension, diabetes, underlying lung disease, or moderate/severe liver disease. However, they were more likely to have active cancer and/or to smoke or misuse alcohol or illicit substances. These patients still experienced substantial morbidity/mortality and hospital resource use.
The authors highlight a need for standardized definitions to allow the distinction between those hospitalizations where COVID-19 is the direct cause, a potential contributing factor, or an incidental finding to better inform hospital resource allocation and public health measures.