Clinical significance of measurements of serum apolipoprotein A-I, A-II and B in hypertriglyceridemic male patients with and without coronary artery disease

To examine the relationship of hypertriglyceridemia to coronary artery disease (CAD), we measured serum cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C) and apolipoproteins (apo) A-I, A-II and B in 82 male patients with angiographically defined CAD and 140 age-matched healthy controls. The CAD patients had significantly lower apo A-I and A-II and HDL-C levels, but had higher apo B and triglyceride levels than the controls. After adjustments of apolipoproteins for serum triglyceride, CAD patients had significantly higher apo B and lower apo A-I and A-II levels than the controls. Discriminant analysis showed that apo B was the best discriminator and that apo A-I was next. In the normotriglyceridemic subgroup HDL-C also had a sufficient power for discrimination between CAD patients and the controls, but in the hypertriglyceridemic subgroup HDL-C had no discriminative power. Both apo A-I and B had significant discriminative power between CAD patients and the controls, independently of the serum triglyceride level. These results indicate that measurements of serum apo A-I and apo B are useful for the study of coronary risk factor in hypertriglyceridemic subjects. Finally, it is necessary to sub-classify dyslipoproteinemia by serum apolipoprotein levels for predicting the future occurrence of CAD in the general population.