Serum lipids, lipoproteins, apolipoproteins (A-1 and B) were determined in 225 patients with angiographic evidence of coronary artery disease (having abnormal coronary angiogram and positive exercise stress test), and 112 patients without any clinical and/or angiographic evidence of coronary artery disease. The variable with the strongest association with coronary artery disease was the ratio of apo B/A-1. Thus, the determination of apolipoproteins yielded complementary information in this case control study and warrants further study in a prospective setting.