Sleep and Biological Rhythms最新文献

Studies have revealed a possible connection between orexin, narcolepsy, and obstructive sleep apnea (OSA). Orexin has an important role in the maintenance of arousal and wakefulness/sleeping states. To better understand the pathophysiological mechanism of OSA, we used a chronic intermittent hypoxia (CIH) model in mice to mimic OSA. In this way, we explored the effect of CIH on the locomotor activity and orexin system in the hypothalamus, cerebral cortex, and brainstem of mice. Male C57BL/6 J mice (8 weeks) in the CIH group were exposed in a hypoxia chamber for 8 h/day for 28 weeks. The re-oxygenation groups comprised the W2 group and W4 group, which were exposed to 28 weeks of CIH followed by 2 weeks and 4 weeks of re-oxygenation, respectively. The open field test was undertaken to observe locomotor activity. mRNA expression of orexin, orexin receptor type 1 (OX₁R), and OX₂R mRNA was evaluated by real-time reverse transcription-quantitative polymerase chain reaction. Mice subjected to long-term CIH exhibited significant anxiety-like behavior during the light period, and this behavior lasted until 4 weeks of re-oxygenation. mRNA expression of orexin was upregulated in the hypothalamus. mRNA expression of OX₁R mRNA in the cerebral cortex and brainstem was downregulated by CIH. Two weeks and 4 weeks of re-oxygenation could not reverse these alternations. Long-term CIH may induce anxiety-like behavior and re-oxygenation cannot reverse these behavior. Moreover, OX₁R has a significant role in the anxiety-related symptoms observed in long-term CIH.

Eighty patients with chronic insomnia and 50 normal controls were selected. Evaluation scales included Pittsburgh Sleep Quality Index, Dysfunctional Beliefs and Attitudes about Sleep, Montreal Cognitive Assessment, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Ruminative Responses Scale and Social Disability Screening Schedule. All patients and controls underwent whole-brain DTI scanning and Tract-Based Spatial Statistics (TBSS) analysis was performed. Chronic insomnia patients are mainly accompanied by white matter lesions of right posterior thalamic radiation, right sagittal tract, and right upper longitudinal tract. TBSS is helpful in the diagnosis of chronic insomnia and can reflect the changes of cognitive function.

Coronavirus disease 2019 (COVID-19) pandemic has caused widespread increase in stress and affected sleep quality and quantity, with up to 30% prevalence of sleep disorders being reported after the declaration of the pandemic. This study aimed to assess perceived changes due to the pandemic in the prevalence of insomnia and excessive daytime sleepiness (EDS) in Korea, and identify the associated factors. An online survey was conducted among 4000 participants (2035 men and 1965 women) aged 20-69 years enrolled using stratified multistage random sampling according to age, sex, and residential area, between January, 2021 and February, 2022. The questionnaire included various items, such as socio-demographics, Insomnia Severity Index, and Epworth Sleepiness Scale (ESS). Insomnia was defined as difficulty falling asleep and difficulty maintaining sleep more than twice a week. EDS was classified as an ESS score ≥ 11. Insomnia was reported by 32.9% (n = 1316) of the participants (37.3% among women and 28.6% among men). Multivariate logistic regression revealed that insomnia was associated with female sex [odds ratio (OR) = 1.526, 95% confidence interval (CI) = 1.297-1.796], night workers (OR 1.561, 95% CI 1.160-2.101), and being unmarried (OR 1.256, 95% CI 1.007-1.566). EDS was reported by 12.8% (n = 510) of the participants (14.7% among men and 10.7% among women). EDS was associated with male sex (OR 1.333, 95% CI 1.062-1.674), and being employed (OR 1.292, 95% CI 1.017-1.641). During the COVID-19 pandemic, the prevalence of insomnia increased in Korea, while there was no significant change in EDS compared with pre-pandemic evidence.

[This corrects the article DOI: 10.1007/s41105-020-00262-0.].

Health effects of weekend catch-up sleep (CUS) could differ depending on both the ability to obtain sufficient sleep during weekdays and amount of weekend CUS required to compensate for sleep lost during the week. Using data from 3128 middle-aged (40-64 years) participants of the Sleep Heart Health Study, we examined the longitudinal association of these two aspects of sleep with all-cause mortality. CUS was calculated as the difference in self-reported habitual sleep duration between weekends and weekdays, and classified into no, short (1 h), and long (2 h or more) CUS. Polysomnography-measured total sleep time, representing the ability to obtain sufficient sleep, was classified into short (< 360 min) or normal (≥ 360 min) sleep durations. We estimated multivariable-adjusted mortality hazard ratios (HRs) and 95% confidence intervals (CIs) for six groups divided by the extent of CUS and sleep duration. Participants were followed up for a median (interquartile range) of 12.3 (11.3-13.5) years. Short weekend CUS with normal sleep duration was associated with lower mortality compared to no CUS with normal sleep duration (HR, 0.48; 95% CI 0.27-0.83). When stricter cutoffs were applied for sleep durations, while the protective effect of short CUS with normal sleep duration (≥ 390 min) was strengthened (HR, 0.36; 95% CI 0.17-0.78), the harmful effect of short CUS with short sleep duration (< 330 min) emerged (HR, 1.84; 95% CI 1.08-3.14). Results highlight the importance of balancing sleep ability and CUS. Sufficient sleep may reduce weekday sleep debt and only a short CUS would be required on weekends, improving mortality in middle-aged adults.

Supplementary information: The online version contains supplementary material available at 10.1007/s41105-023-00460-6.

This study aimed to answer the question of how media users will reallocate their sleep time when their main content channel changes from real-time broadcasting to selective viewing through the over-the-top (OTT) media streaming service. To draw a causal inference between OTT consumption and sleep patterns, the difference-in-difference (DID) estimation method was applied. With the DID approach, a clear distinction between treatment and control groups is essential because the main treatment effects can be screened by the compounding effects. While the conventional way of dividing two groups relies on the selection of limited variables, this study adopted random forest nearest-neighbor propensity score matching based on a machine learning algorithm to divide the two groups. This allows for meticulous matching of the two groups except for treatment. Results show that watching OTT late at night has a significant effect on reducing the total sleep duration on average by about 18-20 min (maximum about 30 min at 95% confidence level) and delaying bedtime by about 18 min (maximum about 26 min at 95% confidence level). This study showed that the selective viewing of content through OTT has the advantage of widening the range of content choices for media users and helping in arranging their time more autonomously, but watching content through OTT late at night leads to media users' departure from the existing sleep routine.