Long-term prognostic scores may underestimate the risk of death in patients with heart failure with reduced ejection fraction in whom red cells distribution width is elevated

INTRODUCTION: Risk prediction in patients with heart failure with reduced ejection fraction (HFrEF) is one of the key challenges for clinicians. Novel biomarkers aggregating several important pathophysiological pathways may modify the diagnostic discrimination of validated scores. The red cell distribution width (RDW) is a cheap and easily available measure of anisocytosis, and was shown to have a strong independent prognostic power in short- and medium‑term prognosis in HFrEF. OBJECTIVES: Our aim was to assess the prognostic power of RDW in optimally treated chronic HFrEF, and to investigate whether different RDW may impact the prognostic accuracy of validated long‑term scores in HFrEF. PATIENTS AND METHODS: The study included 551 patients at a median (interquartile range [IQR]) age of 54 (47-59) years, of whom 86.6% were men. The patients represented the median New York Heart Association class III (IQR, II-III), and ischemic etiology occurred in 56.6% of the cases. In all patients, RDW as a coefficient of variation was calculated, along with Meta‑Analysis Global Group in Chronic Heart Failure Score (MAGGIC‑HF) and Seattle Heart Failure Survival Model (SHFSM). RESULTS: The patients were followed for 5 years and all‑cause mortality was assessed. We recorded 166 (30.1%) and 225 (40.8%) deaths at 3 and 5 years, respectively. Scores based on MAGGIC‑HF and SHFSM algorithms for the respective prediction of 3- and 5‑year mortality were calculated for each patient and compared with the observed mortality. There was a significant underestimation of mortality in the patients with RDW above 15.4% (reference values, 11.5%-14.5%), while in those with lower RDW SHFSM overestimated the actual risk. The excess mortality in the higher RDW group was confirmed by the Hosmer-Lemeshow statistic. CONCLUSIONS: The RDW has a strong prognostic value in chronic HFrEF, independently of the risk assessed by the MAGGIC‑HF or the SHFSM score.