1. From the Framingham Heart Study, Framingham, MA (S.C., R.S.V.); Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.C.); Cardiology Section, Boston University School of Medicine, Boston, MA (R.S.V.); and Preventive Medicine Section, Boston University School of Medicine, Boston, MA (R.S.V.).