Matsushita K, et al. - A recent study showed that patients with heart failure (HF) with mid-range ejection fraction (HFmrEF) more frequently had comorbid diabetes relative to other patients. The link between glycosylated hemoglobin (HbA1c) and in-hospital mortality in acute HF patients with reduced, mid-range, and preserved EF was explored in this current investigation. In acute HF patients with mid-range EF, but not in those with preserved or reduced EF, HbA1c was shown to be an independent risk factor for in-hospital mortality.