Serum iron: a new predictor of adverse outcomes independently from serum hemoglobin levels in patients with acute decompensated heart failure

Abstract Iron is an essential trace element in the body. However, in heart failure (HF), iron is only recognized as the cause of anemia. Actually, iron itself affects myocardial exercise tolerance and cardiac function via mitochondrial function. Therefore, it is necessary to clarify the pathological significance of iron in acute HF, irrespective of concomitant anemia. We investigated the impact of serum iron level at discharge on the prognosis of 615 patients emergently admitted with acute decompensated HF (ADHF). Patients were divided into two groups according to the median level of serum iron (62 µg/dL). The endpoint was the composite outcome, which included all-cause mortality and readmission for HF. During the mean follow-up period of 32.1 months, there were 333 events. Kaplan–Meier analysis showed that the incidence of the composite outcome was significantly higher in the Low iron group (P