1. From the Department of Medicine, Divisions of Clinical Pharmacology (J.V.G., N.J.B.) and Nephrology (Y.W., J.H.C.) and the Department of Biochemistry (A.B., M.R.W.), Vanderbilt University Medical School, Nashville, Tenn; BioVentures Inc (E.P.D., K.E.W., S.W.G.), Murfreesboro, Tenn; Department of Biostatistics (L.A.C., C.-Y.G., S.D.), Boston University School of Public Health, Boston, Mass; and National Heart, Lung, and Blood Institute/Framingham Heart Study (C.J.O.), Framingham, Mass.