AUTHOR=Campodonico Jeness , Carulli Ermes , Doni Francesco , Russo Gerardo Lo , Junod Daniele , Gaudenzi Asinelli Margherita , Bonomi Alice , De Martino Fabiana , Vignati Carlo , Pezzuto Beatrice , Agostoni Piergiuseppe TITLE=Is red distribution width a valid tool to predict impaired iron transport in heart failure? JOURNAL=Frontiers in Cardiovascular Medicine VOLUME=10 YEAR=2023 URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2023.1133233 DOI=10.3389/fcvm.2023.1133233 ISSN=2297-055X ABSTRACT=Background

Impaired iron transport (IIT) is a form of iron deficiency (ID) defined as transferrin saturation (TSAT) < 20% irrespective of serum ferritin levels. It is frequently observed in heart failure (HF) where it negatively affects prognosis irrespective of anaemia.

Objectives

In this retrospective study we searched for a surrogate biomarker of IIT.

Methods

We tested the predictive power of red distribution width (RDW), mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC) to detect IIT in 797 non-anaemic HF patients.

Results

At ROC analysis, RDW provided the best AUC (0.6928). An RDW cut-off value of 14.2% identified patients with IIT, with positive and negative predictive values of 48 and 80%, respectively. Comparison between the true and false negative groups showed that estimated glomerular filtration rate (eGFR) was significantly higher (p = 0.0092) in the true negative vs. false negative group. Therefore, we divided the study population according to eGFR value: 109 patients with eGFR ≥ 90 ml/min/1.73 m2, 318 patients with eGFR 60–89 ml/min/1.73 m2, 308 patients with eGFR 30–59 ml/min/1.73 m2 and 62 patients with eGFR < 30 ml/min/1.73 m2. In the first group, positive and negative predictive values were 48 and 81% respectively, 51 and 85% in the second group, 48 and 73% in the third group and 43 and 67% in the fourth group.

Conclusion

RDW may be seen as a reliable marker to exclude IIT in non-anaemic HF patients with eGFR ≥60 ml/min/1.73 m2.