Pneumonia Severity Index and CURB-65 Are Good Predictors of Mortality in Hospitalized Patients with SARS-CoV-2 Community-Acquired Pneumonia

Abstract Background CURB-65 and Pneumonia Severity Index (PSI) are well-established clinical prediction rules for predicting mortality in patients hospitalized with community-acquired pneumonia (CAP). SARS-CoV-2 has emerged as a new etiologic agent for CAP, but the role of CURB-65 and PSI have not been established. Research Question How effective are CURB-65 and PSI at predicting in-hospital mortality from SARS-CoV-2 CAP compared to non-SARS-CoV-2 CAP? Can these clinical prediction rules be optimized to predict mortality in SARS-CoV-2 CAP by addition of procalcitonin and D-dimer? Study Design and Methods Secondary analysis of two prospective cohorts of patients with SARS-CoV-2 CAP or non-SARS-CoV-2 CAP from eight adult hospitals in Louisville, KY. Results The in-hospital mortality rate was 19% for patients with SARS-CoV-2 CAP and 6.5% for patients with non-SARS-CoV-2 CAP. For the PSI score, ROC analysis resulted in AUC of 0.82 (95% CI: 0.78 – 0.86) and 0.79 (95% CI: 0.77 – 0.80) for patients with SARS-CoV-2 CAP and non-SARS-CoV-2 CAP, respectively. For the CURB-65 score, ROC analysis resulted in AUC of 0.79 (95% CI: 0.75 – 0.84) and 0.75 (95% CI: 0.73 – 0.77) for patients with SARS-CoV-2 CAP and non-SARS-CoV-2 CAP, respectively. In SARS-CoV-2 CAP, addition of D-dimer (optimal cut-off 1813 ug/mL) and procalcitonin (optimal cut-off 0.19 ng/mL) to PSI and CURB-65 provided negligible improvement in prognostic performance. Interpretation PSI and CURB-65 can predict in-hospital mortality for patients with SARS-CoV-2 CAP and non-SARS-CoV-2 CAP comparatively. In patients with SARS-CoV-2 CAP, the inclusion of either D-dimer or procalcitonin to PSI or CURB-65 did not improve the prognostic performance of either score. In patients with CAP, regardless of etiology, PSI and CURB-65 remain adequate for predicting mortality in clinical practice.