Biomarker of severity in hospitalised patients with COVID-19: a retrospective study

Abstract

Background The novel COVID-19 was rapidly spreading and was highly contagious. COVID-19 caused over 6 million deaths worldwide, with high mortality rates, particularly in severe cases.Objective This study aimed to investigate whether serum albumin-neutrophil count to lymphocyte count ratio (NLR) score (ANS) could be used as a prognostic indicator of COVID-19 severity.Design A retrospective study.Participants Based on the WHO diagnostic criteria, patients were classified as either non-severe (n=270) or severe (n=100).Primary and secondary outcome measures NLR, serum albumin level and ANS.Main results The NLR of patients with severe disease was significantly higher than that of those with non-severe disease. Serum albumin levels were significantly lower in patients with severe disease than in those with non-severe disease. The cut-off values representing the maximum potential effectiveness of serum albumin and NLR were 33.5 g/L and 8.25, respectively, according to the Youden index. In patients with severe COVID-19, we observed that the serum albumin level, NLR and ANS were independent prognostic indicators of severe COVID-19 using logistic analysis. The relative risk of severe COVID-19 was 7.65 (95% CI 3.72 to 15.75, p<0.05) in the ANS 2 group compared with that in ANS 0.Conclusions ANS could be used as a prognostic indicator of COVID-19 severity.