The UK Prospective Diabetes Study was the first study to investigate the effectiveness of glycemic control in patients with type 2 diabetes. Since then, many studies have evaluated the impact of intensive glycemic control on diabetes-related morbidities and mortality. The results of these studies were intended to change the paradigm for controlling glycated hemoglobin and preventing diabetes-related complications, but the beneficial outcomes were limited to microvascular diseases rather than diabetes-related cardiorenal diseases and deaths. This has emphasized the need for comprehensive management of other risk factors (hypertension, dyslipidemia, renal failure, etc.) in addition to hyperglycemia to prevent atherosclerotic cardiovascular diseases and end-stage renal disease in type 2 diabetes. Since 2008, clinical trials to demonstrate cardiovascular safety have shown a beneficial effect of sodium-glucose transporter 2 inhibitors or glucagon-like peptide-1 receptor agonists on macrovascular or renal complications in patients with type 2 diabetes. Recently, major societies around the world including the Korean Diabetes Association, have shifted the goals of diabetes management from the typical glucocentric view to cardiorenal outcome-oriented (organ protection) care, which has been widely accepted and is gradually applied to primary care.
Heart failure (HF) in patients with diabetes mellitus has long been considered a consequence of coronary artery disease (CAD). However, recent epidemiological evidence on patients with diabetes showed a significantly increased prevalence of HF in patients with no significant stenosis in the coronary artery. As such, these are thought to be separate entities of diabetic complications. Therefore, HF in patients with diabetes is now considered an independent disease entity of the ‘diabetic heart.’ The mechanism of ‘diabetic heart’ could be due to CAD and diabetic cardiomyopathy caused by altered energy metabolism in the myocardium and advanced glycation end-product accumulation, altered calcium handling, and oxidative stress in the myocardium. Recent cardiovascular outcome trials of anti-diabetic medications have shown the protective effects of certain drugs against HF in patients with and without diabetes. In this review, the relationship between diabetes and the treatment and prevention of HF is summarized.