The National Early Warning Score on admission predicts severe disease and in-hospital mortality of the coronavirus disease 2019 Delta variant: A retrospective cohort study

Background: Clinical risk scores are widely used in emergency medicine, and some studies have evaluated their use in patients with coronavirus disease 2019 (COVID-19). However, no studies have evaluated their use in patients with the COVID-19 Delta variant. We aimed to study the performance of four different clinical scores (National Early Warning Score [NEWS], quick Sequential Organ Failure Assessment [qSOFA], Confusion, Respiratory rate, Blood pressure, and Age =65 [CRB-65], and Kanagawa score) in predicting the risk of severe disease (defined as the need for intubation and in-hospital mortality) in patients with the COVID-19 Delta variant.Methods: This was a retrospective cohort study of patients hospitalized with suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant infection between June 1 and December 31, 2021. The primary outcomes were the sensitivity and specificity of the aforementioned clinical risk scores at admission to predict severe disease. Areas under the receiver operating characteristic curves (AUROCs) were compared between the clinical risk scores and we identified new cut-off points for all four scores.Results: A total of 249 adult patients were included, of whom 18 developed severe disease. A NEWS =7 at admission predicted severe disease with 72.2% sensitivity and 86.2% specificity. The NEWS (AUROC 0.88) was superior to both the qSOFA (AUROC 0.74) and the CRB-65 (AUROC 0.67), and there was no significant difference between the NEWS and Kanagawa score (AUROC 0.86).Conclusion: The NEWS at hospital admission predicted the severity of the COVID-19 Delta variant with high accuracy.