Prognostic implications of neutrophil-lymphocyte ratio in COVID-19.

Jimeno Ruiz, Sara; Ventura, Paula Sol; Castellano Vázquez, Jose María; García-Adasme, Salvador I; Miranda García, Mario; Touza Pol, Paula; Llana Martín, Isabel; López Escobar, Alejandro

BACKGROUND The clinical presentation of COVID-19, ranges from a mild, self-limiting disease, to multiple organ failure, and death. Most severe COVID-19 cases present low lymphocytes counts, high leukocytes counts and, accumulated evidence suggests that in a subgroup of patients presenting severe COVID-19, there may be a hyperinflammatory response driving a severe hypercytokinaemia which may be, at least in part, signaling the presence of an underlying endothelial dysfunction. In this context, available data suggest a prognostic role of neutrophil-lymphocyte ratio (NLR) in various inflammatory diseases and oncological processes. Following this rationale, we hypothesized that NLR, as a marker of endothelial dysfunction, may be useful in identifying patients with a poor prognosis in hospitalized COVID-19 cases. DESIGN A retrospective observational study performed at Hospital Universitario HM Puerta del Sur, Madrid, Spain, which included 119 patients with COVID-19 from March 1 to March 31, 2020. Patients were categorized according to WHO R&D Expert Group. RESULTS Forty five (12.1%) patients experienced severe acute respiratory failure requiring respiratory support. Forty seven (12.6%) patients died. Those with worse outcomes were older (p=0.002) and presented significantly higher NLR at admission (p=0.001), greater increase in Peak NLR (p<0.001) and higher increasing speed of NLR (p=0.003) compared to follow up patients. In a multivariable logistic regression, age, cardiovascular disease, C-Reactive-Protein at admission and Peak NLR were significantly associated with death. CONCLUSIONS NLR is an easily measurable, available, cost effective and reliable parameter which continuous monitoring could be useful for the diagnosis and treatment of COVID-19.