[1] Northwestern Univ, Feinberg Sch Med, Dept Prevent Med, 680 North Lake Shore Dr,Suite 1400, Chicago, IL 60611 USA
[2] NHLBI, Div Cardiovasc Sci, Bldg 10, Bethesda, MD 20892 USA
[3] Univ Alabama Birmingham, Dept Med, Div Prevent Med, Birmingham, AL 35294 USA
[4] NIA, Lab Epidemiol & Populat Sci, Bethesda, MD 20892 USA
[5] Univ Penn Hlth Syst, Dept Radiol, Philadelphia, PA USA
[6] Univ Calif San Francisco, Dept Psychiat Neurol & Epidemiol, San Francisco, CA 94143 USA
[7] Kaiser Permanente No Calif, Div Res, Oakland, CA USA
[8] Univ Geneva, CH-1211 Geneva 4, Switzerland