Apolipoproteins A-1 and B concentration were measured in 201 Indian patients (32 females; 169 males) undergoing elective diagnostic coronary arteriography in order to assess the predictive power of apolipoproteins as a 'marker' of coronary artery disease (CAD). This association was also compared to that of other traditional risk factors: age, hypertension, diabetes, family history, smoking and plasma levels of total cholesterol, triglycerides, low and high density lipoproteins. The apolipoprotein (Apo) A-1 levels averaged 82.9 +/- 18.9 mg/dl in the normal coronary group (n = 43) and 76.0 +/- 18.1 mg/dl in the group with coronary artery disease (n = 158). The average Apo B levels in the normal coronary group and coronary artery disease group were 67.8 +/- 17.7 mg/dl and 78.9 +/- 19.5 mg/dl, respectively. Overall Apo B and triglyceride levels (of all lipid measures) showed larger univariate difference between the normal group (no coronary artery disease) and the group with coronary artery disease. The variable with strongest predictive power for coronary artery disease was the ratio of Apo A-1 to Apo B. These findings were confirmed using multiple logistic regression analysis adjusting for age and other traditional risk factors. Our results indicate that the measurement of apolipoproteins A-1 and B provide a better marker for predicting the presence of coronary artery disease as compared to traditional lipid measures. Overall the levels of these apolipoproteins seem to be lower in Indian population as compared to those reported from the West.