Dyslipidemia and Type 2 Diabetes Mellitus: Implications and Role of Antiplatelet Agents in Primary Prevention of Cardiovascular Disease

Abstract

Dyslipidemia is the major risk factors for macrovascular complications leading to cardiovascular disease (CVD) in type 2 diabetes mellitus (T2DM). In addition to this, endothelial dysfunction, platelet hyperactivity, impaired fibrinolytic balance and abnormal blood flow may accelerate atherosclerosis and increased risk of thrombotic vascular events (Colwell & Nesto, 2003). Macrovascular disease is the most common cause of morbidity and mortality in T2DM (Koskinen, 1998). Macrovascular disease is defined as illnesses affecting the larger arteries supplying the heart, brain, and the legs, thereby causing ischemic heart disease, cerebrovascular disease, and peripheral vascular disease (Thompson, 1999). In patients with diabetes, alteration in distribution of lipid increased risk of atherosclerosis. Specifically, insulin resistance and insulin deficiency was identified as phenotype of dyslipidemia in diabetes mellitus (Taskinen, 2003; Krauss & Siri, 2004; Chahil & Ginsberg, 2006). This was characterized with high plasma triglyceride level, low HDL cholesterol level and increased level of small dense LDL-cholesterol (Mooradian, 2008). In these patient also, the increment of free fatty-acid release is due to insulin resistance. With the presence of adequate glycogen stores in the liver, this will promote triglyceride production, which stimulates the secretion of apolipoprotein B (Apo B) and VLDL cholesterol (Mooradian, 2008). Hepatic production of VLDL cholesterol is enhanced due to disability of insulin to inhibit the release of free fatty-acid. Low HDL cholesterol levels were also associated with hyperinsulinemia. There are several associations between dyslipidemia and the increased risk of cardiovascular disease in patients with type 2 diabetes mellitus. Low HDL cholesterol and increased triglyceride levels may contribute to the increased risk of cardiovascular disease. In conjunction with increased small dense LDL cholesterol and low HDL cholesterol levels, further evidence suggests that acceleration of atherosclerosis in diabetes mellitus and insulin-resistant conditions is regulated by hypertriglyceridemia. Nevertheless, the association between LDL cholesterol and CHD risk is stronger compared to the association between hypertriglyceridemia and CHD risk. Type 2 diabetes is also associated with insulin resistance and hyperinsulinemia or syndrome X comprises hypertension, dyslipidemia,