1. Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
2. Department of Biostatistics, University of Washington, Seattle, WA, USA
3. Department of Medicine, Division of Cardiology , Johns Hopkins Hospital, Baltimore, MD, USA
4. Departments of Environmental & Occupational Health Sciences, Medicine, and Epidemiology, University of Washington, Seattle, WA, USA