Abstract: Article Clinical Predictors of Mortality and Critical Illness in Patients with COVID-19 Pneumonia Maamoun Basheer 1,*, Elias Saad 1,2,*, Rechnitzer Hagai 3 and Nimer Assy 1,2,* Internal Medicine Department, Galilee Medical Center, Nahariya 2210001, Israel The Azrieli Faculty of Medicine, Bar-Ilan University, Safad 1311502, Israel 3 The Microbiology Lab, Galilee Medical Center, Nahariya 2210001, Israel; HagaiR@gmc.gov.il * Correspondence: maamon.basheer@mail.huji.ac.il (M.B.); eliass@gmc.gov.il (E.S.); nimera@gmc.gov.il (N.A.) 1 2 Abstract: Background/Aim: Early identification of patients with COVID-19 who will develop severe or critical Citation: Basheer, M.; Saad, E.; Hagai, R.; Assy, N. Clinical Predictors of Mortality and Critical Illness in Patients with COVID-19 Pneumonia. Metabolites 2021, 11, 679. https://doi.org/10.3390/ disease symptoms is important for delivering proper and early treatment. We analyzed demographic, clinical, immunological, hematological, biochemical and radiographic findings that may be of utility to clinicians in predicting COVID-19 severity and mortality. Methods: Electronic medical record data from patients diagnosed with COVID-19 from November 2020 to June 2021 in the COVID-19 Department in the Galilee Medical Center, Nahariya, Israel, were collected. Epidemiologic, clinical, laboratory and imaging variables were analyzed. Multivariate stepwise regression analyses and discriminant analyses were used to identify and validate powerful predictors. The main outcome measure was invasive ventilation, or death. Results: The study population included 390 patients, with a mean age of 61 ± 18, and 51% were male. The non-survivors were mostly male, elderly and overweight and significantly suffered from hypertension, diabetes mellitus type 2, lung disease, hemodialysis and past use of aspirin. Four predictive factors were found that associated with increased disease severity and/or mortality: age, NLR, BUN, and use of high flow oxygen therapy (HFNC). The AUC or diagnostic accuracy was 87%, with a sensitivity of 97%, specificity of 60%, PPV of 87% and NPP of 91%. The cytokine levels of CXCL-10, GCSF, IL-2 and IL-6 were significantly reduced upon the discharge of severely ill COVID-19 patients. Conclusions: The predictive factors associated with increased mortality include age, NLR, BUN, and use of HFNC upon admission. Identifying those with higher risks of mortality could help in early interventions to reduce the risk of death. metabo11100679 Academic Editor: Amedeo Lonardo Keywords: SARS-COV-2; NLR; high flow; BUN; insulin resistance; mortality; cytokine storm; predictors Received: 20 September 2021 Accepted: 30 September 2021 Published: 2 October 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Highlights: 1. We analyzed demographic, clinical, immunological, hematological, biochemical and radiographic findings. 2. The following four predictive factors were found that were associated with increased disease severity and/or mortality: age, NLR, BUN, and use of high flow oxygen therapy. 3. The AUC or diagnostic accuracy was 87%, with a sensitivity of 97. 4. Identifying those with higher risks of mortality could help in early interventions to reduce the risk of death.