Geographic variation in short and long sleep duration and poor sleep quality: a multilevel analysis using the 2015-2018 Canadian community health survey.

BACKGROUND: There is a dearth of evidence on geographic variation in sleep duration and quality, and about the effect of geographic location or "place" on sleep. The objective was to assess the magnitude of geographic variation in sleep duration and sleep quality in Canada, while controlling for individual-level factors. METHODS: Data from the 2015-2018 cycles of the Canadian Community Health Survey were used. The sample consisted of 96,484 respondents from 6 provinces. Multilevel logistic regression techniques were used to assess the magnitude of geographic variation in self-reported measures of short and long sleep duration and 3 indicators of sleep quality (difficulty initiating and maintaining sleep, daytime sleepiness, and finding sleep refreshing) across geographic areas, defined by the boundaries of Forward Sortation Areas. RESULTS: Overall, 45.31% of respondents reported short sleep, 2.31% reported long sleep, 46.97% had difficulty initiating and maintaining sleep, 29.50% had daytime sleepiness, and 39.11% did not find their sleep refreshing. After controlling for individual-level factors, geographic variation accounted for 4.00% and 13.67% of overall variance in short and long sleep duration, respectively; the corresponding estimates for difficulty initiating and maintaining sleep, daytime sleepiness, and finding sleep refreshing were 3.04%, 3.80%, and 5,08%, respectively. CONCLUSIONS: There is a significant level of geographic variation in short and long sleep duration and sleep quality and this variation cannot be accounted for by differential distribution of individual characteristics across geographic areas. Future research is warranted to examine specific contextual factors that can account for this variation.