[1] Framingham Heart Dis Epidemiol Study, Framingham, MA 01702 USA
[2] Boston Univ, Dept Epidemiol & Biostat, Sch Publ Hlth, Boston, MA 02215 USA
[3] Harvard Univ, Sch Med, Div Cardiol, Massachusetts Gen Hosp, Boston, MA 02115 USA
[4] Harvard Univ, Beth Israel Deaconess Med Ctr, Sch Med, Dept Med, Boston, MA 02215 USA
[5] Harvard Univ, Hebrew Rehabil Ctr Aged, Sch Med, Res & Training Inst,Div Aging, Boston, MA 02215 USA
[6] NHLBI, NIH, Bethesda, MD 20892 USA