1. Group Health Research Institute, Group Health, Seattle, Washington;
2. Department of Psychiatry and Behavioral Sciences, University of Washington School of Medicine, Seattle, Washington;
3. Cardiovascular Health Research Unit, Department of Epidemiology, School of Public Health and Community Medicine, University of Washington, Seattle, Washington;
4. Epidemiologic Research and Information Center, Veterans Affairs Puget Sound Health Care System, University of Washington School of Medicine, Seattle, Washington;
5. Department of Medicine/Dermatology, University of Washington School of Medicine, Seattle, Washington.