Ezetimibe (Zetia): A New Type of Lipid-Lowering Agent

Abstract

Coronary heart disease is the leading cause of death in adults in the USA. It has been associated with elevated levels of low-density lipoprotein (LDL) cholesterol and reduced levels of high-density lipoprotein (HDL) cholesterol. Premature coronary atherosclerosis is a major manifestation of hyperlipidemia. Because atherosclerosis is one of the major causes of coronary heart disease, controlling plasma lipid levels is essential. According to the National Health and Nutrition Examination Survey (1988–1994) and the National Cholesterol Education Program Adult Treatment Panel III, an estimated 100,870,000 American adults have total cholesterol levels ≥200 mg/dL and are at increased risk of developing coronary heart disease. Treatment should address both diet and pharmacological therapy regimens. It may be concluded that 7% of American adults are candidates for lipid-lowering agents, since dietary intervention alone reduces LDL cholesterol by only 10%. Modification of risk factors such as hyperlipidemia may be beneficial in slowing the atherosclerotic process and preventing cardiovascular mortality (1). Therapeutic lifestyle changes include dietary changes, weight reduction, and increased physical activity. For those patients who are at high risk of coronary heart disease, LDL cholesterol—lowering drug therapy may be essential. Such drugs include hydroxymethylglutaryl coenzyme A reductase inhibitors (statins), bile acid sequestrants, nicotinic acid, and fibric acids. Guidelines indicating the utilization of these agents have been set by the National Cholesterol Education Program Adult Treatment Panel III (1). Ezetimibe (Zetia) is distinct from these agents because it does not inhibit cholesterol synthesis in the liver or increase bile acid excretion. It belongs to a class of lipid-lowering compounds that selectively inhibits the intestinal absorption of cholesterol and related phytosterols. Ezetimibe's pharmacological effect is complementary to that of the statins (1).