The triglyceride-high-density lipoprotein axis: an important target of therapy?

Coronary heart disease is the single largest cause of morbidity and mortality in the United States. The link between elevated low-density lipoprotein cholesterol (LDL-C) levels and coronary heart disease (CHD) has been clearly established. However, triglycerides (TG) are increasingly believed to be independently associated with CHD, while high-density lipoprotein cholesterol (HDL-C) is inversely associated with CHD risk. High TG and low HDL often occur together, often with normal levels of LDL-C, and can be described as abnormalities of the TG-HDL axis. This lipid abnormality is a fundamental characteristic of patients with the metabolic syndrome, a condition strongly associated with the development of both type 2 diabetes and CHD. Patients with high TG and low HDL-C should be aggressively treated with therapeutic lifestyle changes. For high-risk patients, lipid-modifying therapy that specifically addresses the TG-HDL axis should also be considered. Current pharmacologic treatment options for such patients include statins, fibrates, niacin, fish oils, and combinations thereof. Several new pharmacologic approaches to treating the TG-HDL axis are currently being investigated. More clinical trial data is needed to test the hypothesis that pharmacologic therapy targeting the TG-HDL axis reduces atherosclerosis and cardiovascular events.