[1] Univ Calif Los Angeles, Sch Med, Div Geriatr Med, Los Angeles, CA USA
[2] Univ So Calif, Dept Prevent Med, Los Angeles, CA 90089 USA
[3] Univ So Calif, Andrus Gerontol Ctr, Los Angeles, CA USA
[4] NIA, Lab Epidemiol Demog & Biometry, Bethesda, MD 20892 USA