The importance of serum lipids & lipoprotein as risk factors in the development and potentiation of atherosclerotic coronary artery disease(CAD) is now supported by the epidemiological and population studies. Lp(a) is composed of LDL particle and apo(a) is considered to have not only atherogenic but also antifibrinolytic activities. The purpose of this study was to evaluate lipoprotein and Lp(a) as risk factor of CAD, and to study the relationship between Lp(a) and other lipids in the patients with CAD.

We determined plasma level of lipids(Total cholesterol, HDL-C, Triglyceride, LDL-C)and apolipoprotein(apo A, apo B) and Lp(a) in the 315 patients with coronary artery disease and 106 control patients confirmed by coronary angiography. Serum Lp(a) was measured by ELISA and other lipid profiles by conventional methods.

The ratio of male(61 vs 44%) and the prevalence of hypertension(44 vs 17%), diabetes(16 vs 3%) and smoking(48 vs 32%) were higher in patients with CAD compared with control group. Total cholesterol(187±52 vs 173.2±36ml/dl) and LDL-C(114±43 vs 97.2±35ml/dl)were significantly higher(p<0.05) and the HDL-C(40±12 vs 49±12ml/dl) and Apo Al/Apo B ratio(1.3±1 vs 1.6±1) were significantly lower in the patients with CAD(p<0.01). The level of Lp(a) of the CAD group was significantly higher than that of the control group(27±22 vs 15±15ml.dl, p<0.01). Also Lp(a) concentration in the younger than 60 year old was higher than those of elderly patient(29±23 vs 26±22mg/dl, p<0.01). However, there were no sexual difference and Lp(a) showed a low correlation coefficient(r=0.02-0.14)with other lipid profiles in both groups.

These results suggest that the derangement of serum lipids are strongly associated with CAD and the measurement of serum lipids and apolipoproteins are able to predict the risk of CAD. Also, Lp(a) is an independent risk factor for the development of CAD.