Neutrophil-to-Lymphocyte Ratios Are Closely Associated With the Severity and Course of Non-mild COVID-19

Front Immunol. 2020 Sep 2:11:2160. doi: 10.3389/fimmu.2020.02160. eCollection 2020.

Abstract

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is spreading worldwide. Measuring the prevention and control of the disease has become a matter requiring urgent focus.

Objective: Based on coronavirus disease 2019 (COVID-19) clinical data from Wuhan, we conducted an in-depth analysis to clarify some of the pathological mechanisms of the disease and identify simple measures to predict its severity early on.

Methods: A total of 230 patients with non-mild COVID-19 were recruited, and information on their clinical characteristics, inflammatory cytokines, and T lymphocyte subsets was collected. Risk factors for severity were analyzed by binary logistic regression, and the associations of neutrophil-to-lymphocyte ratios (N/LRs) with illness severity, disease course, CT grading, inflammatory cytokines, and T lymphocyte subsets were evaluated.

Results: Our results showed that the N/LRs were closely related to interleukin (IL)-6 and IL-10 (P < 0.001, P = 0.024) and to CD3+ and CD8+ T lymphocytes (P < 0.001, P = 0.046). In particular, the N/LRs were positively correlated with the severity and course of the disease (P = 0.021, P < 0.001). Compared to the values at the first test after admission, IL-6 and IL-10 were significantly decreased and increased, respectively, as of the last test before discharge (P = 0.006, P < 0.001). More importantly, through binary logistic regression, we found that male sex, underlying diseases (such as cardiovascular disease), pulse, and N/LRs were all closely related to the severity of the disease (P = 0.004, P = 0.012, P = 0.013, P = 0.028).

Conclusions: As a quick and convenient marker of inflammation, N/LRs may predict the disease course and severity level of non-mild COVID-19; male sex, cardiovascular disease, and pulse are also risk factors for the severity of non-mild COVID-19.

Keywords: Neutrophil-to-lymphocyte ratios; cytokines; immune damage; inflammation; severity and course of non-mild COVID-19.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Betacoronavirus / immunology*
  • Biomarkers
  • COVID-19
  • Cardiovascular Diseases
  • Coronavirus Infections / immunology*
  • Coronavirus Infections / virology
  • Female
  • Humans
  • Interleukin-10 / blood
  • Interleukin-6 / blood
  • Lymphocyte Count
  • Male
  • Middle Aged
  • Neutrophils / immunology*
  • Pandemics
  • Pneumonia, Viral / immunology*
  • Pneumonia, Viral / virology
  • Pulse
  • Risk Factors
  • SARS-CoV-2
  • Severity of Illness Index*
  • Sex Factors
  • T-Lymphocyte Subsets / immunology*

Substances

  • Biomarkers
  • IL10 protein, human
  • IL6 protein, human
  • Interleukin-6
  • Interleukin-10