[1] Ewha Womans Univ, Mokdong Hosp, Dept Internal Med, Seoul, South Korea
[2] Yonsei Univ, Severance Hosp, Internal Med, Coll Med, Seoul, South Korea
[3] Natl Hlth Insurance Serv Ilsan Hosp, Internal Med, Goyang, South Korea
[4] Gachon Univ, Gil Med Ctr, Internal Med, Incheon, South Korea
[5] Konkuk Univ, Sch Med, Internal Med, Seoul, South Korea
[6] Yonsei Univ, Gangnam Severance Hosp, Coll Med, Internal Med, Seoul, South Korea