[1] Showa Univ, Northern Yokohama Hosp, Dept Internal Med, Div Nephrol, Yokohama, Kanagawa, Japan
[2] Showa Univ, Koto Toyosu Hosp, Dept Med, Div Nephrol, Tokyo 1358577, Japan
[3] Kitami Touzan Clin, Div Dialysis, Tokyo, Japan
[4] Showa Univ, Sch Med, Dept Med, Div Nephrol, Tokyo, Japan
[5] Showa Univ, Fujigaoka Hosp, Dept Med, Div Nephrol, Yokohama, Kanagawa, Japan
[6] Kawasaki Clin, Dept Dialysis, Kawasaki, Kanagawa, Japan