Sleep and Biological Rhythms最新文献

[This corrects the article DOI: 10.1007/s41105-023-00445-5.].

[This corrects the article DOI: 10.1007/s41105-023-00453-5.].

The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is unclear. According to the cortical hypothesis, severe RBD episode (RBDE) occurs when spinal motoneurons are less inhibited and cortical and limbic systems are more active. We made this study to prove the hypothesis for the development of RBDE using video-polysomnography (VPSG). VPSG records of 35 patients with RBD were analyzed. According to severity, RBDEs were classified into three motor events (MEs): ME 1; small movements or jerks, ME 2; proximal movements including violent behavior, and ME 3; axial movements including bed falls. For each ME, we measured the number of MEs preceded or not preceded by both REM sleep without atonia (RWA) and REMs during the 10-s-period immediately before ME onset. In severe RBDE (ME 3), the number of MEs preceded by both RWA and REMs was significantly higher than that of MEs not preceded by both (0.8 vs. 0.2, P = 0.033). This was not the case for mild RBDE (ME 1) and moderate RBDE (ME 2). Our results suggest that both RWA and REMs are associated with the development of severe RBDE.

Nocturnal enuresis, or bed wetting, is the involuntary urination during sleep. One of its causes is difficulty awakening during sleep, suggesting a relationship between Nocturnal enuresis (NE) and sleep. However, no studies have yet clarified the relationship between NE and sleep, and the effects of sleep structure in NE children are not yet known. Assuming that changes in sleep structure are related to NE, there would be a difference in sleep structure between days with and without NE. We measured the sleep electroencephalograms of 27 at home patients aged 6-16 years, evaluated the differences between days with and without NE, and examined the NE-associated sleep characteristics associated. The evaluation items were total sleep time, sleep efficiency, the ratio of rapid eye movement (REM) to non-REM sleep, REM sleep latency, and non-REM sleep latency. Factors influencing NE were examined by logistic regression analysis, with NE presence/absence as the dependent variable and each evaluation item as the independent variable. Given that 2-6 measurements were made for each patient, Generalized Estimating Equations was used in the analysis. NE positively correlated with prolonged REM sleep latency, but no significant differences were found in other sleep structures. A positive correlation exists between NE and prolonged REM sleep latency. Changes in sleep structure in the early stages of sleep may lead to increased nocturnal urine volume and increased NE frequency.

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.