Dyslipidemia in Type 2 Diabetes and the Effects of Thiazolidinediones

Abstract

Type 2 diabetes is frequently accompanied by multiple metabolic abnormalities, including dyslipidemia. The dyslipidemia characteristic of type 2 diabetes involves increased plasma triglyceride levels, decreased high-density lipoprotein cholesterol concentrations and pro-atherogenic changes in low-density lipoprotein cholesterol subfractions. The association between type 2 diabetes and dyslipidemia represents 1 feature of the insulin resistance syndrome in which impaired insulin sensitivity underlies a clustering of cardiovascular risk factors, including vascular inflammation, endothelial dysfunction and hypertension, as well as dyslipidemia. Effective management of type 2 diabetes requires treatment not only to reduce blood glucose levels, but also to normalize the full range of metabolic abnormalities within the insulin resistance syndrome. Thus, the selection of appropriate antidiabetic therapy should be based not only on glucose-lowering activity, but also on effects across the range of cardiovascular risk factors in type 2 diabetes. The thiazolidinediones are the only antidiabetic agents to target insulin resistance directly and have beneficial effects on many components of the insulin resistance syndrome, including dyslipidemia and hypertension. Consequently, they can have benefits in reducing the burden of cardiovascular morbidity and mortality in patients with type 2 diabetes.