Importance of iron deficiency in patients with chronic heart failure as a predictor of mortality and hospitalizations: insights from an observational cohort study

Abstract

Background: iron deficiency (ID) in patients with chronic heart failure (CHF) is considered an adverse prognostic factor. We aimed to evaluate if ID in patients with CHF is associated with increased mortality and hospitalizations. Methods: we evaluated ID in patients with CHF at 3 university hospitals. ID was defined as absolute (ferritin < 100 μg/L) or functional (transferrin Saturation index < 20% and ferritin between 100 and 299 μg/L). We excluded patients who received treatment with intravenous Iron or Erythropoietin during follow-up. We evaluated if ID was a predictor of death or hospitalization due to heart failure or any cause using univariate and multivariate cox regression analysis. Results: we included 1684 patients, 65% males, 38% diabetics, median age of 72 years, 37% in functional class III-IV and 30% of patients with a left ventricular ejection fraction > 45%. Patients were well treated, with 87% and 88% of patients receiving renin-angiotensin inhibitors and beta-blockers, respectively. Median transferrin saturation index was 20%, median ferritin 155 ng/mL and median haemoglobin 13 g/dL. ID was present in 53% of patients; in 35% it was absolute and in 18% functional. Median follow-up was 20 months. ID was a predictor of death, hospitalization due to heart failure or to any cause in univariate analysis but not after multivariate analysis. No differences were found between absolute or functional ID regarding prognosis. Conclusion: in a real life population of patients with CHF and a high prevalence of heart failure with preserved ejection fraction, ID did not predict mortality or hospitalizations after adjustment for comorbidities, functional class and neurohormonal treatment.