Kentaro Matsui1, Kenichi Kuriyama2, Takuya Yoshiike3, Kentaro Nagao4, Naoko Ayabe5, Yoko Komada6, Isa Okajima7, Wakako Ito8, Jun Ishigooka9, Katsuji Nishimura10, Yuichi Inoue11. 1. Department of Clinical Laboratory, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan; Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan; Japan Somnology Center, Neuropsychiatric Research Institute, Tokyo 1510053, Japan; Department of Psychiatry, Tokyo Women's Medical University, Tokyo 1628666, Japan. Electronic address: matsui.kentaro@ncnp.go.jp. 2. Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. Electronic address: kenichik@ncnp.go.jp. 3. Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. Electronic address: yoshiike@ncnp.go.jp. 4. Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. Electronic address: knagao@ncnp.go.jp. 5. Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. Electronic address: ayabe@ncnp.go.jp. 6. Liberal Arts, Meiji Pharmaceutical University, Tokyo 2048588, Japan. Electronic address: yoko.komada@gmail.com. 7. Department of Psychological Counseling, Faculty of Humanities, Tokyo Kasei University, Tokyo 1730003, Japan. Electronic address: isa.okajima@gmail.com. 8. Japan Somnology Center, Neuropsychiatric Research Institute, Tokyo 1510053, Japan. Electronic address: wakappe@gmail.com. 9. Institute of CNS Pharmacology, Tokyo 1510051, Japan. Electronic address: ishigooka@i-cnsp.com. 10. Department of Psychiatry, Tokyo Women's Medical University, Tokyo 1628666, Japan. Electronic address: nishimura.katsuji@twmu.ac.jp. 11. Japan Somnology Center, Neuropsychiatric Research Institute, Tokyo 1510053, Japan; Department of Somnology, Tokyo Medical University, Tokyo 1608402, Japan. Electronic address: inoue@somnology.com.
Abstract
BACKGROUND: To date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances. METHODS: A web-based cross-sectional survey was conducted with 8698 subjects aged 20-69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D). RESULTS: Daytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7-8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance. CONCLUSIONS: The results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration.
BACKGROUND: To date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances. METHODS: A web-based cross-sectional survey was conducted with 8698 subjects aged 20-69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D). RESULTS:Daytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7-8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance. CONCLUSIONS: The results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration.