1. Northern California Institute for Research and Education, San Francisco
2. Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, Bethesda, Maryland
3. Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis
4. Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, Bethesda, Maryland
5. Division of Research, Kaiser Permanente of Northern California, Oakland
6. Departments of Psychiatry, Neurology, Epidemiology and Biostatistics, University of California, San Francisco7San Francisco Veterans Affairs Medical Center, San Francisco, California