The purpose was to examine whether sleep hygiene practices are associated with the course of insomnia (incidence, persistence and remission) over 1 year in the general population. This longitudinal study was carried out in the general population. After excluding anyone with other primary sleep disorder than insomnia, 1638 participants returned a baseline and a 1-year follow-up survey. Questions regarding sleep hygiene practices were administered at baseline, and the status of insomnia was assessed at baseline (T1) and at the 1-year follow-up (T2). Age, gender, mental ill-health, and pain were used as covariates in the analyses. Nicotine use, mental ill-health and pain were independently associated with an increased risk for concurrent insomnia at T1, while mental ill-health was the only risk factor for incident insomnia at T2. Relative to not reporting insomnia at the two time-points, nicotine use, light or noise disturbance, mental ill-health, and pain significantly increased the risk for persistent insomnia over 1 year. In comparison with those whose insomnia had remitted at the follow-up, reporting an irregular sleep schedule was a significant risk factor for persistent insomnia. Of the nine sleep hygiene practices examined in this study, only three were independently linked to concurrent and future insomnia, respectively; using nicotine late in the evening, light or noise disturbance, and having an irregular sleep schedule. This may have implications for the conceptualization and management of insomnia as well as for future research.
Keywords: Epidemiology; Insomnia; Longitudinal; Nicotine; Sleep hygiene; Sleep timing.