Plasma Lipids and Apolipoproteins as Risk Factor of Ischemic Heart Disease

Chae, Shung Chull; Jun, Jae Eun; Park, Wee Hyun; Kim, Jung Chul; Chung, Tai Ho

Abstract

Recent studies suggest that apolipoproteins may be better predictor of ischemic heart disease than are plasma lipids, such as total cholesterol and high density lipoprotein cholesterol(HDL-C). To examine this hypothesis, plasma levels of major lipids and major apolipo-proteins were measured and their derivatives were calculated in 30 male patients with ischemic heart disease(16 angina pectoris and 14 old myocardial infarction) and 30 age-matched male healthy controls. Plasma levels of lipids were obtained by conventional methods and apolipoproteins by Rocket immunoelectrophoresis. Levels of HDL-C, HDL2-cholesterol(HDL2-C), and apolipoprotein-AII, and ratios of HDL-C/total cholesterol, HDL2-C/total cholesterol, and apolipoprotein-AI/apolipoprotein-B were lower in the group of patients than in controls. Levels of low density lipoprotein cholesterol(LDL-C) and apolipoprotein-B, and ratios of lDL-C/HDL-C and apolipoprotein-AI/apolipoprotein-AII were higher in the group of patients. There were no statistically significant differences in the levels of total cholesterol and apolipoprotein-AI between the two groups. Stepwise discriminators analysis showed that apolipoprotein-B and apolipoprotein-AII were better discriminators than plasma lipids for identifying those with ischemic heart disease. One could correctly classify 78% of the cases by using the levels of the two apolipoproteins. By using the level of apolipoprotein-B, one could correctly classify 73% of the cases. There were no correlations between the levels of total cholesterol and HDL-C in the controls whereas there were positive correlations between the levels in the group of patients. In conclusion, this study showed that apolipoprotein-B was the best single discriminator for identifying the patients with ischemic heart disease, followed by apolipoprotein-AII.