[1] Chonnam Natl Univ, Coll Med, Res Ctr Med Sci, Dept Prevent Med, Kwangju 501746, South Korea
[2] Seonam Univ, Coll Med, Dept Prevent Med, Namwon, South Korea
[3] Chungnam Natl Univ, Coll Med, Dept Prevent Med, Taejon, South Korea
[4] Chonbuk Natl Univ Hosp, Dept Neurol, Jeonju, South Korea
[5] Chosun Univ, Coll Med, Dept Prevent Med, Gwanju, South Korea