[1] Kyoto Univ, Grad Sch Med, Neurol, Kyoto, Japan
[2] Kyoto Univ, Fac Med, Kyoto, Japan
[3] Kansai Elect Power Hosp, Dept Neurol, Ctr Sleep Related Disorders, Osaka, Japan
[4] Osaka Kaisei Hosp, Sleep Med Ctr, Osaka, Japan
[5] Kansai Elect Power Hosp, Dept Neurol, Osaka, Japan
[6] Kansai Elect Power Med Res Inst, Div Sleep Med, Osaka, Japan