[1] Okayama Univ, Dept Gastroenterol Surg, Grad Sch Med Dent & Pharmaceut Sci, Okayama 7008558, Japan
[2] Okayama Univ, Dept Palliat Med, Grad Sch Med Dent & Pharmaceut Sci, Okayama 7008558, Japan
[3] Okayama Univ, Palliat Care Team, Okayama Univ Hosp, Okayama 7008558, Japan
[4] Okayama Univ, Grad Sch Hlth Sci, Okayama 7008558, Japan
[5] Okayama Univ, Grad Sch Interdisciplinary Sci & Engn Hlth Syst, Okayama 7008558, Japan
[6] Okayama Saiseikai Gen Hosp, Dept Internal Med, Okayama 7008511, Japan
[7] Kawasaki Med Sch, Dept Anesthesiol & Intens Care 1, Kurashiki, Okayama 7010192, Japan