Lymphocytes screening on admission is essential for predicting in-hospital clinical outcome in COVID-19 patients: A retrospective cohort study

Introduction We aimed to identify the associations between the lymphocytes (LYM) absolute count on admission and clinical outcomes in COVID-19 patients. Methods In this retrospective study, 224 COVID-19 patients who were admitted to General Hospital of Central Theater Command of the PLA from January 22 to April 4, 2020, were consecutively included. These patients were divided into the lymphopenia group and the nonlymphopenia group according to whether the LYM count on admission was below the normal range. Results During hospitalization, patients in the lymphopenia group have a much higher all-cause mortality (14.5% vs 0.0%; P < .001) and an evidently longer length of hospital stay (24.0 vs 17.5 days; P < .001) than patients in the nonlymphopenia group. The correlation analysis results indicated that the LYM count was negatively correlated with the values of NEU (R = -.2886, P < .001), PT (R = -.2312, P < .001), FIB (R = -.2954, P < .001), D-D (R = -.3554, P < .001), CRP (R = -.4899, P < .001), IL-6 (R = -.5459, P < .001), AST (R = -.2044, P < .01), Cr (R = -.1350, P < .05), CPK (R = -.2119, P < .01), CK-Mb (R = -.1760, P < .01), and LDH (R = -.4330, P < .001), and was positively correlated with the count of PLT (R = .2679, P < .001). In addition, LYM as a continuous variable was associated with 97% decreased risk of in-hospital mortality in the fully adjusted models (OR = 0.03, 95%CI, 0.00-0.37, P < .001). Discussion LYM screening on admission is a critical predictor for assessment of disease severity and clinical outcomes in patients with COVID-19, and lymphopenia substantially correlates with poor clinical outcomes.