Search

Aims: Chronic hyperglycaemia, assessed by elevated glycated haemoglobin (A1C), is a known risk factor for heart failure (HF) and cardiovascular (CV) death among subjects with diabetes. Whether this risk varies with left ventricular ejection fraction (LVEF) is unknown. This study evaluated whether A1C influences a composite outcome of either HF hospitalization or CV death differently along the spectrum of LVEF., Methods and Results: We assessed the relationships of baseline A1C and LVEF with a composite outcome of either CV death or HF hospitalization in the 4091 patients with type 2 diabetes and a recent acute coronary syndrome enrolled in the ELIXA trial who had available LVEF. We assessed for interaction between A1C and LVEF as continuous variables with respect to this outcome. During a median follow-up of 25.7 months, 343 patients (8.4%) had HF hospitalization or died of CV causes. In a multivariable model, A1C and LVEF were each associated with an increased risk of HF hospitalization or CV death [adjusted hazard ratio (HR) 1.11, 95% confidence interval (CI) 1.01-1.21 per 1% higher A1C, and adjusted HR 1.39, 95% CI 1.27-1.51 per 10% lower in LVEF]. Both A1C and LVEF were independently and incrementally associated with risk without evidence of interaction (P for interaction = 0.31). Patients with A1C ≥ 8% and LVEF <40% were at threefold higher risk than those with A1C < 7% and LVEF ≥50% (adjusted HR 3.18, 95% CI 2.03-4.98, P < 0.001)., Conclusion: In a contemporary cohort of patients with type 2 diabetes and acute coronary syndrome, baseline chronic hyperglycaemia was associated with an increased risk of HF hospitalization or CV death independently of LVEF., (© 2020 European Society of Cardiology.)

Responding to concerns about the potential for increased risk of adverse cardiovascular outcomes, specifically myocardial infarction, associated with certain glucose-lowering therapies, the US Food and Drug Administration and the Committee for Medicinal Products for Human Use of the European Medicines Agency issued guidance to the pharmaceutical industry in 2008. Glucose-lowering therapies were granted regulatory approval primarily from smaller studies that have demonstrated reductions in glycated hemoglobin concentration. Such studies were overall underpowered and of insufficient duration to show any effect on cardiovascular outcomes. The 2008 guidance aimed to ensure the cardiovascular safety of new glucose-lowering therapies to treat patients with type 2 diabetes mellitus. This resulted in a plethora of new cardiovascular outcome trials, most designed primarily as placebo-controlled noninferiority trials, but with many also powered for superiority. Several of these outcome trials demonstrated cardiovascular benefits of the newer agents, resulting in the first-ever cardiovascular protection indications for glucose-lowering therapies. Determining whether the guidance continues to have value in its current form is critically important as we move forward after the first decade of implementation. In February 2018, a think tank comprising representatives from academia, industry, and regulatory agencies convened to consider the guidance in light of the findings of the completed cardiovascular outcome trials. The group made several recommendations for future regulatory guidance and for cardiovascular outcome trials of glucose-lowering therapies. These recommendations include requiring only the 1.3 noninferiority margin for regulatory approval, conducting trials for longer durations, considering studying glucose-lowering therapies as first-line management of type 2 diabetes mellitus, considering heart failure or kidney outcomes within the primary outcome, considering head-to-head active comparator trials, increasing the diversity of patients enrolled, evaluating strategies to streamline registries and the study of unselected populations, and identifying ways to improve translation of trial results to general practice. [ABSTRACT FROM AUTHOR]