1. Division of Endocrinology and Metabolism; Department of Internal Medicine; St. Vincent's Hospital; The Catholic University of Korea; Seoul Korea
2. Division of Endocrinology and Metabolism; Department of Internal Medicine; Yeouido St. Mary's Hospital; The Catholic University of Korea; Seoul Korea
3. Division of Cardiology; Department of Internal Medicine; St. Vincent's Hospital; The Catholic University of Korea; Seoul Korea
4. Department of Health and Human Services; Epidemiology Branch; National Institute of Environmental Health Sciences; National Institutes of Health; Research Triangle Park; NC USA
5. Division of Nephrology; Department of Internal Medicine; St. Vincent's Hospital; The Catholic University of Korea; Seoul Korea