Upon completion of the chapter, the reader will be able to:
Identify the common types of lipid disorders.
Identify the statin-benefit groups and intensity of statin therapy according to the American College of Cardiology/American Heart Association.
Recommend appropriate therapeutic lifestyle changes (TLC) and pharmacotherapy interventions for dyslipidemia.
Determine a patient’s atherosclerotic cardiovascular disease risk and corresponding treatment goals according to the National Lipid Association.
Identify diagnostic criteria and treatment strategies for metabolic syndrome.
Describe components of a monitoring plan to assess effectiveness and adverse effects of pharmacotherapy for dyslipidemias.
Educate patients about the disease state, appropriate TLC, and drug therapy required for effective treatment.
Coronary heart disease (CHD) is the leading cause of death in adults in the United States and most industrialized nations. It is also the chief cause of premature, permanent disability in the US workforce. KEY CONCEPT Hypercholesterolemia and other abnormalities in serum lipids play a major role in atherosclerosis and plaque formation leading to CHD as well as other forms of atherosclerotic cardiovascular disease (ASCVD), such as carotid and peripheral artery disease.1
EPIDEMIOLOGY AND ETIOLOGY
Annually, approximately 515,000 Americans experience a new heart attack and 205,000 will have a recurrent event.2 Lowering cholesterol reduces atherosclerotic progression and mortality from CHD and stroke. The development of CHD is a lifelong process. Except in rare cases of severely elevated serum cholesterol levels, years of poor dietary habits, sedentary lifestyle, and life-habit risk factors (eg, smoking and obesity) contribute to the development of atherosclerosis.3
Cholesterol and Lipoprotein Metabolism
Cholesterol, an essential substance manufactured by most cells in the body, is used to maintain cell wall integrity and for the biosynthesis of bile acids and steroid hormones. Cholesterol, triglycerides and phospholipids circulate in the blood as lipoproteins (Figure 12–1). The major lipoproteins are chylomicrons, very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL). A measured total cholesterol is the total cholesterol molecules in all these major lipoproteins. The estimated value of LDL cholesterol is found using the following equation (after fasting for 9 to 12 hours):
Lipoprotein structure. Lipoproteins are a diverse group of particles with varying size and density. They contain variable amounts of core cholesterol esters and triglycerides, and have varying numbers and types of surface apolipoproteins. The apolipoproteins function to direct the processing and removal of individual lipoprotein particles.
Where triglycerides/5 or triglycerides/2.2 estimate VLDL cholesterol in units of mg/dL or mmol/L, respectively.
This formula becomes inaccurate if serum triglycerides are greater than 400 mg/dL (4.52 mmol/L), if chylomicrons are present, or the patient has type III hyperlipoproteinemia. In each of ...