Hypercholesterolemia has long loomed large amidst the various risk factors for coronary disease. A vast amount of effort and expense has gone into the study of its cause, mechanism, epidemiology, and possible correction by diet and drugs. Even now, despite recent doubts, the plasma cholesterol level is believed by many to be a reliable atherogenic index.
With increasing understanding of the metabolism and transport of cholesterol, this simplistic index gave way to a sophisticated schema in which the low-density β-lipoprotein cholesterol level, rather than the total plasma cholesterol level became a key to atherogenesis.
However, the lipoprotein story did not end there. A new contender, high-density α-lipoprotein cholesterol, entered the atherogenic arena. A number of investigators recently reexamined the effect of this lipoprotein on atherogenesis—an effect observed by Barr et al1 in 1951 but ignored since that time. In contrast with the atherogenic β-lipoprotein, the high-density α-lipoprotein appears to