[1] Seoul Natl Univ, Dept Internal Med, Coll Med, Seoul, South Korea
[2] Seoul Natl Univ, Dept Internal Med, Bundang Hosp, Seongnam, South Korea
[3] Kyung Hee Univ, Dept Internal Med, Div Nephrol, Sch Med, Seoul, South Korea
[4] Sungkyunkwan Univ, Samsung Med Ctr, Dept Med, Div Endocrinol & Metab,Sch Med, Seoul, South Korea
[5] Catholic Univ Korea, Coll Med, Dept Internal Med, Div Endocrinol & Metab,St Vincents Hosp, Suwon, South Korea
[6] Korea Univ, Dept Prevent Med, Coll Med, Seoul, South Korea
[7] Inje Univ, Sch Med, Dept Internal Med, Div Nephrol,Busan Paik Hosp, Busan, South Korea
[8] Pusan Natl Univ, Dept Internal Med, Div Nephrol, Sch Med, 20 Geumo Ro, Yangsan 50612, South Korea
[9] Seoul Natl Univ, Dept Internal Med, Seoul Metropolitan Govt, Boramae Med Ctr, Seoul, South Korea