[1] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94107 USA
[2] Kaiser Permanente, Div Res, Oakland, CA 94612 USA
[3] Univ Calif San Francisco, Dept Psychiat, San Francisco, CA 94143 USA
[4] Univ Calif San Francisco, Dept Neurol, San Francisco, CA 94143 USA
[5] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94143 USA
[6] San Francisco VA Med Ctr, San Francisco, CA 94121 USA