A Nationwide Cross-Sectional Survey of Sleep-Related Problems in Japanese Visually Impaired Patients: Prevalence and Association with Health-Related Quality of Life

Abstract

Study Objectives: 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. Methods: 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. Results: 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 sleepwake pattern or difficulty waking up at the desired time, which was associated with lower mental/physical QOL. Conclusions: 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. Keywords: circadian rhythm sleep-wake disorder, health-related quality of life, light perception, prevalence, sleep-related problems, visual impairment I NTRO DUCTI O NVisually impaired individuals are likely to have any of several comorbid mental/physical disorders including diabetes mellitus, hypertension, cognitive impairment, and depression/ anxiety. [1][2][3][4][5][6] The severity of these mental/physical disorders is reportedly correlated with visual impairment.1-9 Therefore, those individuals might be at risk for lower health-related quality of life (QOL). 7-10Sleep-related problems have been observed frequently in visually impaired individuals.11-15 Reportedly, especially in people without light perception (LP), inhibited transmission of light signals to the suprachiasmatic nuclei might cause sleeprelated problems because of external desynchronization of the biological clock. 16,17 Indeed, the rate of circadian-related sleepwake disorders is likely to be higher among visually impaired individuals without LP than among those with LP.12 In Japan, no large nationwide study of this subject has ever been reported. The actual prevalence of sleep-related problems amon...

The association between visual impairment and fatigue: a systematic review and meta‐analysis of observational studies

“…Together with 14 articles identified through manual searches and reference lists, this resulted in 22 articles that were included in this review. We received responses from six out of 19 contacted authors and two authors provided additional data . Forty‐three articles were excluded because they had no fatigue outcomes; 35 articles because the participants were not visually impaired; 23 articles because they had no control group or used comparison groups that were not relevant for our analysis (e.g.…”

“…We received responses from six out of 19 contacted authors and two authors provided additional data. 24,25 Forty-three articles were excluded because they had no fatigue outcomes; 35 articles because the participants were not visually impaired; 23 articles because they had no control group or used comparison groups that were not relevant for our analysis (e.g. comparison groups based on disease severity rather than presenting or post-refraction VA); 17 articles because they provided insufficient data for meta-analysis (e.g.…”

“…conference abstract); seven articles because of language-restrictions; and one article because they utilised the same sample source from a study that was already included. 10 Of the 22 included studies, nine used a crosssectional design, 9,10,26-32 eight compared cases with controls, 8,24,[33][34][35][36][37][38] and five studies compared the target population to normative data. 25,[39][40][41][42] Findings from the normative comparison studies were summarised by a narrative approach.…”

“…24,36,39 With regard to fatigue outcomes, visual impairment was defined as besteye presenting VA worse than 20/60 (6/18, 0.33) in three studies; 8,26,27 as best-eye post-refraction VA less than 20/ 60 (6/18, 0.33) in one study 30 ; as best-eye post-refraction VA worse than 20/40 (6/12, 0.50) in one study 10 ; as besteye presenting VA worse than 20/40 (6/12, 0.50) in one study 31 ; as binocular presenting VA of 20/40 (6/12, 0.50) or worse in one study 28 ; and as best-eye post-refraction VA of 20/1000 (6/300, 0.02) or worse in another study. 24 Because of the limited number of identified studies, we decided to include all abovementioned criteria of visual impairment and blindness. For case-control studies, control groups were comprised of persons without ocular disease in three studies, 34,35,37 healthy participants without chronic disability in two studies, 36,38 persons with normal (self-reported) vision in two studies, 8,24 and hospital controls without glaucoma in one study.…”

“…24 Because of the limited number of identified studies, we decided to include all abovementioned criteria of visual impairment and blindness. For case-control studies, control groups were comprised of persons without ocular disease in three studies, 34,35,37 healthy participants without chronic disability in two studies, 36,38 persons with normal (self-reported) vision in two studies, 8,24 and hospital controls without glaucoma in one study. 33 Quality assessment Table 2 shows the methodological quality of the individual studies pooled by meta-analysis in this review.…”