1. From Boston University's and the National Heart, Lung, and Blood Institute's Framingham Heart Study (M.G.L., B.T.L., R.S.V., D.L., E.J.B.), Framingham, MA; the Cardiology (N.M.H., R.S.V., J.A.V., E.J.B.) and Preventive Medicine Sections (R.S.V., E.J.B.) and Whitaker Cardiovascular Institute, School of Medicine (N.M.H., R.S.V., J.A.V., E.J.B.), and School of Public Health (J.P., L.M.S., E.J.B.), and the Departments of Mathematics and Statistics (M.G.L.), Boston University, Boston, MA; Cardiovascular...