SARS-CoV-2 respiratory infection is associated with significant morbidity and mortality in hospitalized patients. We aimed to assess the risk factors for hospital mortality in non-vaccinated patients during the 2021 spring wave in the Czech Republic. A total of 991 patients hospitalized between January 2021 and March 2021 with a PCR-confirmed SARS-CoV-2 acute respiratory infection in two university hospitals and five rural hospitals were included in this analysis. After excluding patients with unknown outcomes, 790 patients entered the final analyses. Out of 790 patients included in the analysis, 282/790 (35.7%) patients died in the hospital; 162/790 (20.5) were male and 120/790 (15.2%) were female. There were 141/790 (18%) patients with mild, 461/790 (58.3%) with moderate, and 187/790 (23.7%) with severe courses of the disease based mainly on the oxygenation status. The best-performing multivariate regression model contains only two predictors-age and the patient's state; both predictors were rendered significant (p < 0.0001). Both age and disease state are very significant predictors of hospital mortality. An increase in age by 10 years raises the risk of hospital mortality by a factor of 2.5, and a unit increase in the oxygenation status raises the risk of hospital mortality by a factor of 20.

Centre for Research on Internal Medicine and Cardiovascular Diseases University of Ostrava 703 00 Ostrava Czech Republic

Department of Infectious Diseases University Hospital Ostrava 708 52 Ostrava Czech Republic

Department of Internal Medicine and Cardiology University Hospital Ostrava 708 52 Ostrava Czech Republic

Department of Internal Medicine Associated Medical Facilities 794 01 Krnov Czech Republic

Department of Internal Medicine Bílovec Regional Hospital 743 01 Bílovec Czech Republic

Department of Internal Medicine Fifejdy City Hospital 728 80 Ostrava Czech Republic

Department of Internal Medicine General University Hospital 128 08 Prague Czech Republic

Department of Internal Medicine Havířov Regional Hospital 736 01 Havířov Czech Republic

Department of Internal Medicine Třinec Regional Hospital 739 61 Třinec Czech Republic

Department of Mathematical Analysis and Application of Mathematics Palacky University 771 46 Olomouc Czech Republic

Department of Pulmonary Medicine and Tuberculosis University Hospital Ostrava 708 52 Ostrava Czech Republic

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