Lipoproteins and cardiovascular disease: biological basis and epidemiological studies.

There is a long history to our understanding of the biological basis of lipoproteins in cardiovascular disease and to the key epidemiological studies in this field. Building on a wealth of laboratory evidence explaining the role of cholesterol and lipoproteins in the pathogenesis of atherosclerosis, epidemiological studies have characterized associations between serum lipid abnormalities and the risk of myocardial infarction. While elevation in total cholesterol has been associated with an increased risk of myocardial infarction, this information alone is not sufficient. To adequately predict cardiac risk, blood cholesterol must be further characterized by the high density lipoprotein (HDL) cholesterol present and the ratio of total cholesterol to HDL cholesterol. Several other factors, including such clinical syndromes as the "deadly quartet" of insulin resistance, central obesity, high triglycerides, and hypertension, are also associated with a markedly increased cardiac risk and should be identified; these may require unique therapeutic approaches. In addition to the costs of tertiary prevention and therapy after infarct, the impact of long-term morbidity and the economic consequences of this disease further emphasize the importance of optimizing current therapies and actual practice.