Risk factors and angiographic coronary artery disease: a report from the coronary artery surgery study (CASS).

The findings for 14 risk variables were correlated with the results of coronary arteriography in 8807 patients registered in the interinstitutional Coronary Artery Surgery Study (CASS). Discriminant-function analysis revealed that age, sex, cigarette smoking and the level of blood cholesterol best distinguished between the groups with (6688 patients) and without (2119 patients) coronary artery disease. A family history of coronary artery disease and the presence of hypertension or diabetes were of addition, but less, discriminating value. The relative risk for coronary artery disease in patients with the combination of cigarette smoking and an elevated cholesterol level was high (> 4) in females age 55 years or younger and in males age 35 years or younger. Few females age 45 years or younger (seven of 97) had coronary artery disease when both of these risk factors were absent. In spite of these correlations, only limited gains accrued from the use of discriminant-function analysis in correctly allocating patients into disease and nondisease groups. This indicates that, while certain factors are significantly correlated with coronary arteriographic findings, their value for predicting the presence of coronary artery disease is limited.