Evolution in Understanding of Cardiovascular Outcomes in Diabetes

Abstract

Eighty percent mortality occurs in patients with type 2 diabetes mellitus due to cardiovascular (CV) events like myocardial infarction, stroke and peripheral vascular disease. We learned from United Kingdom Prospective Diabetes Study (UKPDS) that lowering HbA1c reduces both micro and macrovascular complications. However, more recent studies have provided insight that HbA1c reduction may exert only a modest effect in lowering macrovascular complications. In fact, treating hypertension and dyslipidemia may provide a greater benefit in reducing CV events. The last 10 years have changed our understanding of cardiovascular disease (CVD) risk in type 2 diabetes. Earlier it was believed to be due to atherosclerotic cardiovascular disease which was exaggerated by hyperglycemia. Additionally, some antidiabetic medications were also implied to contribute to cardiovascular illness and mortality. It is plausible that insulin resistance may play a significant role in cardiovascular complications as well since it induces endothelial dysfunction much earlier before type 2 diabetes is diagnosed. Many patients manifest CVD in form of either atherosclerotic cardiovascular disease (ASCVD) or heart failure prior to diagnosis of diabetes. Amelioration of insulin resistance may be the management key in type 2 diabetes and can be very well achieved with modern drugs although attaining and maintaining desirable glycemic control may be as crucial as noted in type 1 diabetes.