Prediction of in-hospital mortality of patients with SARS-CoV-2 infection by comorbidity indexes: an Italian internal medicine single center study.

OBJECTIVE Clinical outcomes in patients hospitalized for severe acute respiratory syndrome due to coronavirus (SARS-CoV-2) infection seems to be closely related with burden of comorbidities. A comorbidity score could help in clinical stratification of patients admitted to internal medicine units. Our aim was to assess a novel modified Elixhauser index (mEi) and the Charlson Comorbidity Index (CCI) for predicting in-hospital mortality (IHM) in internal medicine patients with SARS-CoV-2 infection. PATIENTS AND METHODS This single-center retrospective study enrolled all consecutive patients discharged from internal medicine unit with confirmed SARS-CoV-2 infection. Both the mEi and CCI were easily calculated from administrative data. Comorbidity scores were tested using receiver operating characteristic (ROC) analysis, and the respective area under the curve (AUC). RESULTS The total sample consisted of 151 individuals, and 30 (19.9%) died during their hospital stay. Deceased subjects were older (82.8±10.8 vs. 63.3±18.1 years; p<0.001) and had a higher burden of comorbidities: the mEi and CCI were 29.9±11 vs. 8.8±9.2 and 4.6±2.6 vs. 1.2±2 (p<0.001), respectively. Only the mEi was independently associated with IHM (OR 1.173), and ROC curves analysis showed that the AUCs were 0.863 and 0.918 for the CCI and for mEi, respectively. CONCLUSIONS In patients admitted to internal medicine wards with SARS-CoV-2 infection, the mEi showed a better performance in predicting IHM than CCI.