1. Division of Geriatrics, Department of Family Medicine, Korea University College of Medicine, Seoul, Korea
2. Center for Obesity and Metabolic Diseases, Korea University Anam Hospital, Seoul, Korea
3. Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
4. Department of Family Medicine, Hallym University College of Medicine, Chuncheon, Korea
5. Department of Biostatistics, College of Medicine, The Catholic University of Korea, Seoul, Korea
6. Division of Upper Gastrointestinal Surgery, Department of Surgery, Korea University College of Medicine, Seoul, Korea