Sleeping at the Limits: The Changing Prevalence of Short and Long Sleep Durations in 10 Countries

Abstract

Short (≤6 hours) and long (>9 hours) sleep durations are risk factors for mortality and morbidity. To investigate whether the prevalences of short and long sleep durations have increased from the 1970s to the 2000s, we analyzed data from repeated cross-sectional surveys of 10 industrialized countries (38 nationally representative time-use surveys; n = 328,018 adults). Logistic regression models for each country were used to determine changes in the prevalence of short and long sleep durations over time, controlling for sampling differences in gender, age, number of weekend days included, and season of data collection. Over the periods covered by data, the prevalence of short sleep duration increased in Italy (adjusted odds ratio = 2.64, 95% confidence interval (CI): 2.41, 2.89) and Norway (adjusted odds ratio = 2.33, 95% CI: 1.77, 3.08) but decreased in Sweden, the United Kingdom, and the United States. The prevalence of long sleep duration increased in Australia (adjusted odds ratio = 1.14, 95% CI: 1.05, 1.25), Finland (adjusted odds ratio = 1.30, 95% CI: 1.14, 1.48), Sweden (adjusted odds ratio = 1.51, 95% CI: 1.35, 1.69), the United Kingdom (adjusted odds ratio = 2.03, 95% CI: 1.68, 2.46), and the United States (adjusted odds ratio = 1.50, 95% CI: 1.36, 1.65) but decreased in Canada and Italy. No changes were observed in Germany or the Netherlands. Limited increases in short sleep duration challenge the claim of increasingly sleep-deprived societies. Long sleep duration is more widespread than is short sleep duration. It has become more prevalent and thus should not be overlooked as a potential contributor to ill health.

Sleep Duration and Sleep Patterns in Chinese University Students: A Comprehensive Meta-Analysis

“…[20][21][22][23][24][25] In contrast, long sleep duration can also be associated with negative outcome, such as increased risk of cardiovascular disease and cognitive impairment. [26][27][28] To date there has been no gold standard criteria for short and long sleep duration. Epidemiological studies usually defined self-reported short and long sleep duration as less than 6 or 7 hours per day and more than 8 or 9 hours per day, respectively.…”

“…Epidemiological studies usually defined self-reported short and long sleep duration as less than 6 or 7 hours per day and more than 8 or 9 hours per day, respectively. 26,[29][30][31] Some researchers suggested 7 to 8 hours per day as appropriate for the university students, whereas fewer than 7 hours is defined as short sleep and more than 8 hours is regarded as long sleep. 32,33 The National Sleep Foundation has recommended 7 to 9 hours per day as the appropriate sleep duration for young adults.…”

Could adult female acne be associated with modern life?

“…Over recent years, society is sleeping less and less [2,9,60,62]. Lack of sleep can be considered sleep deprivation, which occurs when the choice is made not to sleep or sleep is prevented due to sleep disturbances such as insomnia and obstructive sleep.…”

Peruvians’ sleep duration: analysis of a population-based survey on adolescents and adults

“…A recent study analyzed data from the 1970s to the 2000s of ten industrialized countries and concluded that long-sleep duration, over nine hours, was more prevalent (Bin et al 2013). However, a systematic review of cross-sectional studies conducted between the 1960s and 2000s in 15 countries reported a mixed trend: whilst seven countries had an increased sleep duration, six had a reduced one (Bin et al 2012).…”

“…Unfortunately there is limited data published on this matter in Latin American countries (LAC). Recent systematic reviews or metaanalysis on sleep patterns, sleep duration and its association with socio-demographic variables have not included any LAC (Bin et al 2013;Galland et al 2012), with the exception of one effort that included Brazil with a study that targeted adolescents (Olds et al 2010). …”