[1] Natl Hosp Org Kurihama Med & Addict Ctr, 5-3-1 Nobi, Yokosuka, Kanagawa 2390841, Japan
[2] Keio Univ, Sch Med, Dept Internal Med, Div Gastroenterol & Hepatol,Shinjuku Ku, 35 Shinanomachi, Tokyo 1608582, Japan
[3] Natl Inst Publ Hlth, Dept Hlth Promot, 2-3-6 Minami, Wako, Saitama 3510104, Japan