[1] Chonbuk Natl Univ, Dept Internal Med, Sch Med, Jeonju 561180, South Korea
[2] Seoul Natl Univ, Coll Med, Dept Internal Med, Seoul 151, South Korea
[3] Boramae Med Ctr, Seoul, South Korea
[4] Chonbuk Natl Univ, Dept Prevent Med, Sch Med, Jeonju 561180, South Korea
[5] Dongguk Univ, Ilsan Hosp, Dept Internal Med, Goyang, South Korea
[6] Inje Univ, Dept Internal Med, Coll Med, Pusan, South Korea
[7] Sungkyunkwan Univ, Kangbuk Samsung Hosp, Dept Internal Med, Sch Med, Seoul, South Korea
[8] Wonkwang Univ, Dept Internal Med, Coll Med, Iksan, South Korea
[9] Res Inst Clin Med, Jeonju, South Korea