[1] Yonsei Univ, Coll Med, Dept Internal Med, Div Endocrinol & Metab, Seoul, South Korea
[2] Yonsei Univ, Coll Med, Severance Hosp, Diabet Ctr, Seoul, South Korea
[3] Yonsei Univ, Coll Med, Grad Sch, Seoul, South Korea
[4] Yonsei Univ, Coll Med, Inst Endocrine Res, Seoul, South Korea
[5] Yonsei Univ, Coll Med, Dept Internal Med, Div Nephrol, Seoul, South Korea
[6] Keimyung Univ, Sch Med, Dept Internal Med, Div Endocrinol & Metab, Daegu, South Korea