Increased Red Cell Distribution Width Is Associated With Disease Severity in Hospitalized Adults With SARS-CoV-2 Infection: An Observational Multicentric Study.

Theodoros Karampitsakos,Petros Bakakos,Vassiliki Panou,Karolina Akinosoglou,Demosthenes Bouros,Stelios Loukides,Ourania Papaioannou,Charalampos Gogos,Athanasios Koromilias,Argyrios Tzouvelekis

doi:10.3389/fmed.2020.616292

Abstract

Background: There is an amenable need for clinically applicable biomarkers in patients with SARS-CoV-2 infection. Red Cell Distribution Width (RDW) has been recently suggested as a prognostic biomarker for COVID-19.Methods: This was an observational study enrolling patients between February 26 and May 15 2020. We aimed to validate the association of the previously published RDW threshold of 14.5% with markers of disease progression and mortality.Results: A total number of 193 hospitalized patients with COVID-19 were enrolled and analyzed. Median age was 61 years (95% CI: 58–64). Patients with baseline RDW ≥14.5% (n = 41, 19.2%) presented with more progressive disease compared to patients with baseline RDW <14.5% (n = 156, 80.8%) as indicated by significant differences in maximum FiO2% during hospitalization (median: 100, 95% CI: 45.2–100, vs. 35, 95% CI: 31–40, p = 0.0001, respectively). Values of RDW ≥14.5% were also strongly associated with increased risk of mortality (HR: 4.1, 95% CI: 0.88–19.23), (p = 0.02).Conclusion: Our study provides evidence to support reproducibility and validity of a specified cut-off threshold of RDW as biomarker of disease severity and mortality in patients with COVID-19.

Highlights

The role of red cell distribution width (RDW) as a prognostic biomarker in various chronic lung diseases has gained much of attention [1, 2]
It has been suggested that arterial hypoxemia leads to increased erythropoietin secretion and to increased RDW through mechanisms that involve regulation of erythrocyte maturation and survival [2]
Studies have shown that in patients with Coronavirus Disease 2019 (COVID-19), the severity of hypoxemia is independently associated with in-hospital mortality and can reliably predict admission to the intensive care unit [4]

Summary

Introduction

The role of red cell distribution width (RDW) as a prognostic biomarker in various chronic lung diseases has gained much of attention [1, 2]. A large prospective study by Foy et al demonstrated that elevated baseline RDW (>14.5%) levels were independently associated with worse clinical outcomes in hospitalized patients with COVID-19 [11]. Peripheral blood biomarkers, including RDW, need to be validated and reproduced in multiple cohorts from different institutions to support their widespread clinical applicability. To this end, we aimed to further validate in a completely different cohort of patients with COVID-19 (validation cohort), derived from a low incidence and mortality country (Greece), the association of RDW threshold of 14.5%, previously published by Foy et al (derivation cohort) with markers of disease progression and mortality [11]. Red Cell Distribution Width (RDW) has been recently suggested as a prognostic biomarker for COVID-19

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Results

Conclusion