1. From the National Heart, Lung, and Blood Institute’s Framingham Heart Study (A.M.M., M.G.L., D.L., R.S.V.), Framingham, Mass; the Divisions of Cardiology and Clinical Epidemiology, Beth Israel Hospital (D.L.), Harvard Medical School, Boston, Mass; the National Heart, Lung, and Blood Institute, Bethesda, Md (D.L.); and the Cardiology Section (R.S.V.) and Department of Preventive Medicine and Epidemiology (R.S.V., M.G.L., D.L.), Boston University School of Medicine, Boston, Mass.