Relation of high-density lipoprotein subfractions and apolipoprotein E isoforms to coronary disease.

Although a variety of methods have become available for the determination of high-density lipoprotein (HDL) subfractions in plasma, a review of published data from nine studies of coronary disease outcomes and 10 investigations of coronary artery disease severity do no suggest that measurement of HDL2-cholesterol (C) and HDL3-C offer any advantage in the prediction of coronary disease over the determination of total HDL-C alone. Apolipoprotein E is typically present in plasma as one of six isoforms, the six being encoded by three common alleles, epsilon 2, epsilon 3, and epsilon 4. The epsilon 3 allele is the most common, the epsilon 4 allele has been reported to be associated with higher cholesterol concentrations, and the epsilon 2 and epsilon 4 alleles are both associated with higher triglyceride concentrations. Clinical and arteriographic studies of coronary disease suggest that vascular disease risk is increased among persons with the epsilon 4 allele.