Neutrophil Percentage and Neutrophil-to-Monocyte Ratio as Independent Risk Factors in the Severity of COVID-19

Abstract BackgroundInflammation plays an important role in progression of the various viral pneumonia containing COVID-19, severe inflammatory responses could lead to an imbalance of immune response. The purpose of this study was to explore the possibility of the white blood count, neutrophil percentage, neutrophil-to-monocyte ratio (NMR) and neutrophil-to-lymphocyte ratio (NLR) at admission to reflect the clinical severity in patients with COVID‐19.MethodsClinical and laboratory data of adult COVID-19 patients in Changsha, China, were collected and analyzed on admission. A logistic regression model was adopted to analyze the association between the disease severity and related risk factors. The receiver operating characteristic (ROC) curve was utilized to analyze the abilities of potential risk factors in the prediction of COVID-19 severity.ResultsCompared with non-severe patients, the severe ones had significantly higher levels of neutrophil percentage (74.9% vs. 62.1%; P < 0.001), NLR (4.1 vs. 2.1; P < 0.001) and NMR (12.4 vs. 8.0; P < 0.001). A regression analysis showed that neutrophil percentage (OR,1.113; 95% CI, 1.020-1.213; P=0.016) and NMR (OR, 1.110; 95% CI, 1.002-1.230; P = 0.046) were significantly associated with severity of COVID-19 patients. ROC curve showed that the area under the curves of neutrophil percentage, NMR and the combination of them were 0.842 (95% confidence interval (CI), 0.782-0.902), 0.790 (95% CI, 0.710-0.871) and 0.851 (95% CI, 0.790-0.911), respectively.ConclusionsNeutrophil percentage and NMR may act as independent risk factors in the severity of COVID-19.