Cholesterol is a sterol, a type of lipid that makes up an essential component of all cell membranes.1 It plays a myriad of important functions in the body, ranging from cellular membrane physiology and dietary nutrient absorption to reproductive functions and stress responses. These nonpolar lipid molecules require lipoprotein particles in order to be transported in the plasma. There are five different classes of plasma lipoproteins: chylomicrons, very-low-density lipoproteins (VLDL), intermediate-density lipoproteins (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL).
LDLs are responsible for transporting cholesterol through the plasma to peripheral tissues and are called LDL-cholesterols (LDL-C).1 Persistently high levels of LDL-C lead to their build-up in the walls of the arteries. These so-called plaques generate an inflammatory response that can lead to the destruction of the arterial wall, thrombotic occlusion, or infarction of the tissues supplied by the affected vessel. This process is the hallmark of atherosclerosis, which is responsible for most cardiovascular events.
Studies of familial hypercholesterolemia helped to clarify the genetic factors that may predispose some individuals to higher levels of circulating LDL-C, increased risk of coronary heart disease, and premature death.2 In addition to genetic factors, lifestyle factors like diet and exercise and co-morbid disease influence an individual’s level of LDL-C.3
- Tabas I. Cholesterol in health and disease. J Clin Invest. 2002;110(5):583-590.
- Austin MA, Hutter CM, Zimmern RL, Humphries SE. Familial hypercholesterolemia and coronary heart disease: a HuGE association review. Am J Epidemiol. 2004;160(5):421-429.
- Vodnala D, Rubenfire M, Brook RD. Secondary causes of dyslipidemia. Am J Cardiol. 2012;110(6):823-825.