Survival curves of in-hospital death
The low CD4+T cells count group (<404 cells/ul) had a higher in-hospital death rate than the high CD4+T cells count group (≥404 cells/ul) during the follow-up period (log rank<0.001, Figure S2).
Results of Cox proportional hazards analyses of in-hospital death
Cox proportional hazard regression analysis was performed to test the associations between the low CD4+T cells count group and in-hospital death for severe COVID-19 patients. Results of univariate analyses indicated that patients with CD4+T<440 cells/ul exhibited a 15.72-fold increase in in-hospital death compared to patients with CD4+T≥440 cells/ul (hazard ratio (HR) :15.72; 95% confidence intervals (CI):3.67-67.35). Meanwhile, age, history of hypertension, white blood cell count, platelet count, lymphocyte count, lymphocyte count low group, creatinine, estimated glomerular filtration rate, D-dimer, sodium ions, CD3+T cells low group, CD8+T low group, presenting ground-glass opacity or local patchy shadowing on CT imaging, required mechanical ventilation or glucocorticoids or intravenous immunoglobulin treatment or antifungal treatment were correlated with the risk of in-hospital death in patients with severe COVID-19 (table 2).
Multivariate survival analysis was performed to identify the independent factors correlated with prognosis. In each model, CD4+T (the low group vs. the high group) was significance which demonstrated that presenting with CD4+T cells count below 404 cells/ul was an independent risk factor for in-hospital death. In addition, variables like white blood cell count, age and platelet count also showed significance for independently predicting in-hospital death in this study (Table S1).