title: Day workers suffering from a wider range of sleep problems are more likely to experience suicidality.
abstract: Both a higher suicide rate and widespread sleep problems are serious health concerns in Japan when compared with those of other countries. We investigated the relationship between suicidal ideation and sleep problems in Japanese day workers using the 3-dimensional sleep scale (3DSS), which measures three sleep elements (phase, quality, and quantity). Data from 635 Japanese day workers (461 mens and 174 womens) were included. The 3DSS was used to assess participants' sleep condition. Participants were classified into eight sleep types based on scores of phase, quality, and quantity: All Good Sleep, Owl (poor phase), Inefficient (poor quality), Short (poor quantity), Owl + Inefficient (poor phase and quality), Owl + Short (poor phase and quantity), Inefficient + Short (poor quality and quantity), and All Poor Sleep. We assessed participants' suicidal ideation using question 19 of the self-rating depression scale (SDS); 119 cases (18.7 %) had ratings of 2-4 for this question and were considered to have suicidal ideation. The higher the number of sleep problems, the higher the risk of suicidal ideation compared to sleep types not indicative of problems. All Poor Sleep had the highest risk of the eight sleep types. Individuals with Owl + Short, Inefficient + Short, or All Poor Sleep had a significant risk of suicidal ideation even after adjusting for hopelessness and nightmares. Our findings suggested that sleep problems assessed by the 3DSS were related to suicidal ideation. Analysis of various aspects of sleep could be helpful for suicide prevention.
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Yuuki
authors.identifier: 0000-0002-2894-544X
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: Department of Neuropsychiatry, Kurume University School of Medicine, Kurume, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Uchimura
authors.affiliation: Department of Neuropsychiatry, Kurume University School of Medicine, Kurume, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ishida
authors.affiliation: Institute of Health and Sports Science, Kurume University, Kurume, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Toyomasu
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Morimatsu
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Mihoko
authors.initials: M
authors.lastname: Mori
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Nanae
authors.initials: N
authors.lastname: Kushino
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Hoshiko
authors.affiliation: Department of Environmental Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume, 830-0011 Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Ishitake
keywords: Depression; Sleep; Sleep deprivation; Suicidal ideation; Suicide