1. Department of Medicine, Korea University College of Medicine, Seoul 02841, Republic of Korea
2. Department of Internal Medicine, Korea University Ansan Hospital, Ansan 15355, Republic of Korea
3. Department of Medicine, CHA University School of Medicine, Seongnam 13496, Republic of Korea
4. Department of Nursing, College of Health Science, Honam University, Gwangju 62399, Republic of Korea