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. 2023 Apr 24;13(1):6635.
doi: 10.1038/s41598-023-33569-2.

The burden of incidental SARS-CoV-2 infections in hospitalized patients across pandemic waves in Canada

Finlay A McAlister  1   2 , Jeffrey P Hau  3 , Clare Atzema  4   5   6 , Andrew D McRae  7 , Laurie J Morrison  4   5 , Lars Grant  8   9 , Ivy Cheng  4   5 , Rhonda J Rosychuk  10 , Corinne M Hohl  3   11 ; Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) Investigators
Collaborators, Affiliations

The burden of incidental SARS-CoV-2 infections in hospitalized patients across pandemic waves in Canada

Finlay A McAlister et al. Sci Rep. .

Abstract

Many health authorities differentiate hospitalizations in patients infected with SARS-CoV-2 as being "for COVID-19" (due to direct manifestations of SARS-CoV-2 infection) versus being an "incidental" finding in someone admitted for an unrelated condition. We conducted a retrospective cohort study of all SARS-CoV-2 infected patients hospitalized via 47 Canadian emergency departments, March 2020-July 2022 to determine whether hospitalizations with "incidental" SARS-CoV-2 infection are less of a burden to patients and the healthcare system. Using a priori standardized definitions applied to hospital discharge diagnoses in 14,290 patients, we characterized COVID-19 as (i) the "Direct" cause for the hospitalization (70%), (ii) a potential "Contributing" factor for the hospitalization (4%), or (iii) an "Incidental" finding that did not influence the need for admission (26%). The proportion of incidental SARS-CoV-2 infections rose from 10% in Wave 1 to 41% during the Omicron wave. Patients with COVID-19 as the direct cause of hospitalization exhibited significantly longer LOS (mean 13.8 versus 12.1 days), 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. However, patients hospitalized with incidental SARS-CoV-2 infection still exhibited substantial morbidity/mortality and hospital resource use.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Participant flow diagram.
Figure 2
Figure 2
Admission type by pandemic wave in study cohort.
See this image and copyright information in PMC

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