Core A, Field and Clinical Operations has five aims. The first is to reexamine 750 of the original study participants near the sixth anniversary of their baseline exam. The second is to update demographic information, medical history, physical activity and dietary habits. The third aim is to perform an oral glucose tolerance test with insulin measurement and to obtain fasting blood specimens for other projects and labs. The fourth is to perform B-mode ultrasonography exams of the internal carotid artery. The fifth is to construct a computerized data file containing these data.