Association between peripheral lymphocyte count and the mortality risk of COVID-19 inpatients

Abstract

Background To explore the relationship between peripheral lymphocyte counts (PLCs) and the mortality risk of coronavirus disease 2019 (COVID-19), as well as the potential of PLC for predicting COVID-19 hospitalized patients death. Methods Baseline characteristics, laboratory tests, imaging examinations, and outcomes of 134 consecutive COVID-19 hospitalized patients were collected from a tertiary hospital in Wuhan city from January 25 to February 24, 2020. Multiple regression analysis was used to analyze the relationship between the PLC at admission and mortality risk in COVID-19 patients and to establish a model for predicting death in COVID-19 hospitalized patients based on PLC. Results After adjusting for potential confounding factors, we found a non-linear relationship and threshold saturation effect between PLC and mortality risk in COVID-19 patients (infection point of PLC: 0.95 × 109/L). Multiple regression analysis showed that when PLCs of COVID-19 patients were lower than 0.95 × 109/L, the patients had a significantly higher mortality risk as compared to COVID-19 patient with PLCs > 0.95 × 109/L (OR 7.27; 95% CI 1.10–48.25). The predictive power of PLC for death in COVID-19 patients (presented as area under the curve) was 0.78. The decision curve analysis showed that PLC had clinical utility for the prediction of death in COVID-19 inpatients. Conclusions PLC had a non-linear relationship with mortality risk in COVID-19 inpatients. Reduced PLCs (< 0.95 × 109/L) were associated with an increased mortality risk in COVID-19 inpatients. PLCs also had a potential predictive value for the death of COVID-19 inpatients.

Low Lymphocytes and IFN-Neutralizing Autoantibodies as Biomarkers of COVID-19 Mortality

“…In our study, we corroborate the strong effect of the low lymphocyte counts on the mortality risk within a SARS-CoV-2 infection. In this sense, we posit that low lymphocytes counts appear as the most robust marker for unfavorable prognosis or even death, as described in other cohorts [3]. Furthermore, we detected an association between having neutralizing auto-Abs and an increased risk of mortality through a univariate model.…”

“…lymphocyte count below 1000 cells/mm 3 [3], C reactive protein (C-RP) over 100 mg/L, ferritin over 500 ng/mL, and D-dimer > 1000 μg/L have been repeatedly identified as risk predictors of severity and mortality in COVID-19 patients.…”

Potential Immune Indicators for Predicting the Prognosis of COVID-19 and Trauma: Similarities and Disparities

“…A reduction of the lymphocyte count, especially total T, CD4+ T, CD8+ T and NK cells along with neutrophilia and thrombocytopenia are typical phenomena following SARS-CoV-2 infection (45,200,201). In mild COVID-19 the decreased lymphocyte count is within the normal range, whereas it appears as lymphopenia in severe COVID-19 (165,202,203). In patients with severe COVID-19, lymphopenia appears within 2 days after initial symptoms and returns to normal ranges after day 18, whereas it persists for a longer time in non-survivor patients (204).…”

Pathological effects of SARS-CoV-2 on hematological and immunological cells: Alterations in count, morphology, and function

“…A decrease in both CD4+ and CD8+ T cells is reported in COVID-19 patients with different disease severities, which is more significant in severe and critical patients [43] , [45] , [51] , [52] , [54] , [57] , [58] , [60] . Histological analysis of deceased COVID-19 patients showed that the CD4+ and CD8+ T cells decreased in the spleen and lymph nodes of these patients [68] .…”

“…The B cell count is not affected by SARS-CoV-2 infection [47] , [55] , [56] even in the severe phase [55] . A decrease in lymphocyte populations can be used as a predictive parameter for determining the severity of the disease and the risk of death in patients with SARS-CoV-2 infection [43] , [50] , [52] , [53] , [54] , [55] , [57] , [58] . However, a recent systematic review found that a low lymphocyte level was correlated with a poor prognosis in general but the association between lymphocyte subsets and the mortality rate of COVID-19 patients was not significant [59] .…”