Gu J, et al. - In this prospective longitudinal study, researchers compared hemoglobin A1c (HbA1c) variability and clinical outcomes for patients with heart failure (HF) with preserved ejection fraction (HFpEF), HF with mid-range ejection fraction (HFmrEF) and HF with reduced ejection fraction (HFrEF). They followed patients with HF and type 2 diabetes mellitus (T2DM) for 42 months after undergoing 3 or more HbA1c determinations during the first 18 months. Cox proportional hazards models were used to determinethe impact risk factors had on death from any cause as well as composite endpoint of death and HF hospitalization between these groups of patients. Compared with HFrEF, lower all-cause death and composite events were reported for HFpEF. They noted that in the three HF phenotypes, death or combined endpoints were independently and similarly predicted by HbA1c variability.