[1] Stanford Univ, Sch Med, Div Nephrol, Dept Med, Palo Alto, CA 94304 USA
[2] Univ Calif San Francisco, Dept Med, Div Geriatr, San Francisco, CA USA
[3] Univ Calif San Francisco, Dept Psychiat & Neurol, San Francisco, CA 94143 USA
[4] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94143 USA
[5] San Francisco VA Med Ctr, San Francisco, CA USA