title: Letter to the Editor.
authors.affiliation: 1National Shimofusa Hospital, Department of Clinical Research, Chiba, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hori
authors.affiliation: 2Nagoya University Graduate School of Medicine, Department of Psychiatry and Psychobiology, Aichi, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Inada
authors.affiliation: 3National Saigata Hospital, Niigata, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Sengan
authors.affiliation: 3National Saigata Hospital, Niigata, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ikeda