title: A Nationwide Cross-Sectional Survey of Sleep-Related Problems in Japanese Visually Impaired Patients: Prevalence and Association with Health-Related Quality of Life.
abstract: This questionnaire-based cross-sectional study was conducted (1) to estimate the prevalence of sleep-related problems, and (2) to explore factors associated with lower physical/mental quality of life (QOL), particularly addressing sleep-related problems among Japanese visually impaired people.
  
  
  
  This nationwide questionnaire-based survey was administered to visually impaired individuals through the Japan Federation of the Blind. Visually impaired individuals without light perception (LP) (n = 311), those with LP (n = 287), and age-matched and gender-matched controls (n = 615) were eligible for this study. Study questionnaires elicited demographic information, and information about visual impairment status, sleep-related problems, and health-related quality of life.
  
  
  
  Visually impaired individuals with and without LP showed higher prevalence rates of irregular sleep-wake patterns and difficulty maintaining sleep than controls (34.7% and 29.4% vs. 15.8%, 60.1% and 46.7% vs. 26.8%, respectively; p < 0.001). These sleep-related problems were observed more frequently in visually impaired individuals without LP than in those with LP. Non-restorative sleep or excessive daytime sleepiness was associated with lower mental/physical QOL in visually impaired individuals with LP and in control subjects. However, visually impaired individuals without LP showed irregular sleep-wake pattern or difficulty waking up at the desired time, which was associated with lower mental/physical QOL.
  
  
  
  Sleep-related problems were observed more frequently in visually impaired individuals than in controls. Moreover, the rates of difficulties were higher among subjects without LP. Sleep-related problems, especially circadian rhythm-related ones, can be associated with lower mental/physical QOL in visually impaired individuals without LP.
authors.affiliation: Department of Somnology, Tokyo Medical University, Tokyo, Japan.|Yoyogi Sleep Disorder Center, Tokyo, Japan.
authors.forename: Norihisa
authors.initials: N
authors.lastname: Tamura
authors.affiliation: Department of Somnology, Tokyo Medical University, Tokyo, Japan.|Department of Life Sciences and Bio-informatics, Division of Biomedical Laboratory Sciences, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Taeko
authors.initials: T
authors.lastname: Sasai-Sakuma
authors.affiliation: Department of Somnology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Morita
authors.affiliation: Department of Somnology, Tokyo Medical University, Tokyo, Japan.|Yoyogi Sleep Disorder Center, Tokyo, Japan.|Japan Foundation for Neuroscience and Mental Health, Tokyo, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Okawa
authors.affiliation: Department of Preventive Medicine and Public Health, Tokyo Medical University, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Inoue
authors.affiliation: Department of Somnology, Tokyo Medical University, Tokyo, Japan.|Yoyogi Sleep Disorder Center, Tokyo, Japan.|Japan Somnology Center, Neuropsychiatric Research Institute, Tokyo, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Inoue
mesh_terms: D000328:Adult; D001766:Blindness / Q000453:epidemiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011788:Quality of Life; D012893:Sleep Wake Disorders / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data; D055815:Young Adult
keywords: circadian rhythm sleep-wake disorder; health-related quality of life; light perception; prevalence; sleep-related problems; visual impairment