1. From the Divisions of Cardiovascular Medicine (B.M.E., P.M.R.) and Preventive Medicine (B.M.E., N.R.C., E.K., P.M.R., A.D.P.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; F. Hoffmann-La Roche Ltd, Pharma, Metabolic and Vascular Diseases, Basel, Switzerland (M.C.M., M.B.); Division of Laboratory Medicine, Department of Pathology, Children's Hospital, Boston, MA (N.R.); and Division of Cardiovascular Medicine, VA Boston Medical Center, Boston, MA (A.D.P.).