Red blood cell distribution width predicts new-onset anemia in heart failure patients

Abstract Background Hematologic abnormalities such as elevated red blood cell distribution width (RDW) as well as anemia are prognostically meaningful among heart failure (HF) patients. The inter-relationship between these hematologic abnormalities in HF is unclear, however. We therefore aimed to assess whether RDW is predicting changes in hemoglobin concentrations as well as onset of anemia. Methods 268 consecutive non-anemic patients with acutely decompensated HF (ADHF) were enrolled at hospital discharge and RDW was measured. At 6 month follow-up, change in hemoglobin as well as new-onset anemia was studied as a function of RDW at discharge. Results RDW at discharge correlated negatively with hemoglobin values at 6 months (r = − 0.220; p < 0.001); a greater decrease in hemoglobin concentration occurred in those with higher values of RDW at discharge (p = 0.004), independently of baseline hemoglobin concentration and other risk factors. At 6 months, 54 patients (20%) developed new-onset anemia. RDW values at discharge were significantly higher among patients who developed new-onset anemia (15.1 ± 2.2 vs. 14.2 ± 1.4, p = 0.005). In integrated discrimination improvement analyses, the addition of RDW measurement improved the ability to predict new-onset anemia (IDI 0.0531, p < 0.001), beyond known risk factors as hemoglobin, renal function, age, diabetes mellitus, sex and HF symptom severity. In adjusted analyses, patients with RDW > 15% (derived from receiver operating characteristic analysis) had a tripling of the risk of new-onset anemia (OR = 3.1, 95% CI 1.5–5.1, p = 0.002). Conclusion Among non-anemic patients with ADHF, RDW measurement at the time of hospital discharge independently predicts lower hemoglobin concentrations and new-onset anemia over a 6-month follow up period.