1. Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul 02447, Republic of Korea
2. Department of Internal Medicine, Inje University Sanggye Paik Hospital, Seoul 01757, Republic of Korea
3. Department of Internal Medicine, School of Medicine, Chonnam National University Hospital, Gwangju 61469, Republic of Korea
4. Department of Internal Medicine, Hallym University College of Medicine, Anyang 14068, Republic of Korea
5. Department of Internal Medicine, Korea University Medical Center, Seoul 08308, Republic of Korea
6. Department of Internal Medicine, Konkuk University School of Medicine, Seoul 05030, Republic of Korea
7. Research Institute of Medical Science, Konkuk University School of Medicine, Seoul 05029, Republic of Korea