Impact of iron deficiency on long-term clinical outcomes of hospitalized patients with heart failure

Background: Iron deficiency (ID) is commonly observed in chronic heart failure (HF) patients and is associated with worse clinical outcomes. While ID is frequent finding in hospitalized heart failure (HHF), its impact on long-term outcome in HHF patients remains unclear. Methods: We evaluated iron status at discharge in 578 HHF patients. Absolute ID was defined as serum ferritin <100 μg/L, and functional ID (FID) was defined as serum ferritin of 100–299 μg/L with transferrin saturation <20%. The primary outcome of interest was the composite of all-cause mortality and HF admission at one year. Results: Among the study population, 185 had absolute ID, 88 had FID and 305 had no evidence of ID. At one-year post-discharge, 64 patients had died and 112 had been readmitted with HF. Patients with absolute ID had more adverse events than those with FID or no ID (p = 0.021). In multivariate Cox regression analyses, absolute ID was significantly associated with increased risk of adverse events at one year (HR 1.50, 95% CI 1.02–2.21, p = 0.040) compared with the remaining patients. Sensitivity analysis revealed that its prognostic effect did not differ across anemic status, or between HF with reduced and preserved ejection fraction (p for interaction = 0.17, 0.68, respectively). Conclusion: Absolute ID, but not FID, at discharge was associated with increased risk of one-year mortality or HF admission in patients with HHF. Further studies are required to evaluate the role of repleting iron stores and its impact on clinical outcomes in patients with HHF.