Background: Duration and other sleep characteristics change as we age. The effects of other demographics on sleep are less clear, although US studies suggest that sleep disorders and duration are influenced by social deprivation and race. Here we use UK Biobank data from almost half-a million adults living in Britain to test the hypothesis that sleep quality shows a ‘social gradient’ in sleep. Methods: Data for this prospective analysis were sourced from the UK Biobank. These consisted of self-reports relating to sleep (duration, waking in the night, sleeping in the day, difficulty waking and snoring), personal wealth (household income, property owning etc), ethnic group, employment and education, as well as post-code-based Townsend indices of social deprivation from c0.5m adults aged 40-70 years. Analyses considered prevalence of each sleep characteristic, and a Positive Sleep Index was derived by combining sleep-related responses. Findings: Almost one-third of participants reported sleeping shorter (24.7%) or longer (7.7%) than age-corrected recommended sleep durations, with the incidence of shorter or longer sleep increasing with social deprivation and varying with ethnicity. Snoring, waking during the night, finding it difficult to get up in the morning and sleeping in the daytime, were subject to similar effects. Regression analyses of our Positive Sleep Index showed that being younger, male, employed, owning one’s home, having a higher household income, higher level of educational achievement and time in education, were all associated with better sleep, as were living in a more affluent area and being white. Interpretation: Sleep quality in the UK shows a social gradient, independently of a range of other demographic and social influences. These sleep inequalities suggest that the protective and recuperative effects of sleep may be disproportionately distributed across the UK and should encourage us to consider the potential benefits of community specific sleep interventions. Funding Information: Funds received from Unilever UK Central Resources Limited to cover application fees, no other funding supported this research. Declaration of Interests: JAG has received research funding, consultancy, travel support, and speaking fees from various industrial companies. PH is employed by Unilever UK Central Resources Limited. Ethics Approval Statement: This retrospective cohort study is based on data from the UKB study that was approved by the North West Multi-Centre Research Ethics Committee; participants provided written informed consent for data collection, data analysis, and record linkage. Re-analysis of UKB data is part of UK Biobank project (NHS National Research Ethics Service 16/NW/0274).
Read full abstract