Metabolic dysfunction and circadian rhythm abnormalities in adolescents with sleep disturbance

Self-Reported Sleep Disturbance is an Independent Predictor of All-Cause Mortality and Respiratory Disease Mortality in US Adults: A Population-Based Prospective Cohort Study

Objective: Self-reported sleep disturbance is common but its association with mortality has rarely been investigated. Methods: This prospective cohort analysis included 41,257 participants enrolled in the National Health and Nutrition Examination Survey from 2005 to 2018. Self-reported sleep disturbance in the present study refers to the patients who have ever consulted doctors or other professionals for trouble sleeping. Univariate and multivariate survey-weighted Cox proportional hazards models were used to evaluate the association of self-reported sleep disturbance with all-cause and disease-specific mortality. Results: Approximately 27.0% of US adults were estimated to have self-reported sleep disturbance. After adjusting for all sociodemographic variables, health behavioral factors, and common comorbidities, participants with self-reported sleep disturbance tend to have higher all-cause mortality risk with a hazard ratio (HR) of 1.17 (95% CI, 1.04-1.32) and chronic lower respiratory disease mortality risk (HR, 1.88; 95% CI, 1.26-2.80), but not cardiovascular disease mortality risk (HR, 1.19; 95% CI, 0.96-1.46) and cancer mortality risk (HR, 1.10; 95% CI, 0.90-1.35). Conclusion: Self-reported sleep disturbance could be associated with higher mortality in adults, and may need to be paid more attention in public health management.

Irregular sleep and cardiometabolic risk: Clinical evidence and mechanisms

Sleep regularity is an essential part of the multidimensional sleep health framework. The phenomenon of irregular sleep patterns is widespread in contemporary lifestyles. This review synthesizes clinical evidence to summarize the measures of sleep regularity and discusses the role of different sleep regularity indicators in developing cardiometabolic diseases (coronary heart disease, hypertension, obesity, and diabetes). Existing literature has proposed several measurements to assess sleep regularity, mainly including the standard deviation (SD) of sleep duration and timing, sleep regularity index (SRI), interdaily stability (IS), and social jetlag (SJL). Evidence on associations between sleep variability and cardiometabolic diseases varies depending on the measure used to characterize variability in sleep. Current studies have identified a robust association between SRI and cardiometabolic diseases. In comparison, the association between other metrics of sleep regularity and cardiometabolic diseases was mixed. Meanwhile, the associations of sleep variability with cardiometabolic diseases differ across the population. SD of sleep characteristics or IS may be more consistently associated with HbA1c in patients with diabetes compared with the general population. The association between SJL and hypertension for patients with diabetes was more accordant than in the general population. Interestingly, the age-stratified association between SJL and metabolic factors was observed in the present studies. Furthermore, the relevant literature was reviewed to generalize the potential mechanisms through which irregular sleep increases cardiometabolic risk, including circadian dysfunction, inflammation, autonomic dysfunction, hypothalamic-pituitary-adrenal (HPA) axis disorder, and gut dysbiosis. Health-related practitioners should give more attention to the role of sleep regularity on human cardiometabolic in the future.

Disruption of the circadian rhythms and its relationship with pediatric obesity

The circadian clock system is an evolutionarily conserved system by which organisms adapt their metabolic activities to environmental inputs, including nutrient availability. The disruption of this system has been pathogenically linked to the disintegration of metabolic homeostasis, leading to the development of metabolic complications, including obesity. Lifestyle factors that disrupt this system have been found to be associated with the development of metabolic disorder, which is most evidenced by the finding that shift workers are at an increased risk of developing various disorders, such as obesity and obesity-related complications. Lifestyle factors that contribute to a misalignment between the internal clock system and environmental rhythms have also been identified in children. A short sleep duration and skipping breakfast are prevalent in children and there is mounting evidence that these factors are associated with an increased risk of pediatric obesity; however, the underlying mechanisms have not yet been elucidated in detail. Our current understanding of the impact of lifestyle factors that cause a misalignment between the internal clock system and environmental rhythms on the development of pediatric obesity is summarized herein, with a discussion of potential mechanistic factors.

Neonatal irritable sleep-wake rhythm as a predictor of autism spectrum disorders

Recently, it has been suggested that sleep problems in autism spectrum disorder (ASD) not only are associated symptoms, but may be deeply related to ASD pathogenesis. Common clinical practice relating to developmental disorders, has shown that parents of children with ASD have often stated that it is more difficult to raise children in the neonatal period because these children exhibit sleep problems. This study investigated the possibility that abnormal neonatal sleep-wake rhythms are related to future ASD development.

We administered questionnaires to assess parent(s) of children with ASD and controls. A retrospective analysis was conducted among 121 children with ASD (94 male and 27 female children) recruited from the K-Development Support Center for Children (K-ASD), 56 children with ASD (40 male and 16 female children) recruited from the H-Children's Sleep and Development Medical Research Center (H-ASD) and 203 children (104 male and 99 female children) recruited from four nursery schools in T-city (control).

Irritable/over-reactive types of sleep-wake rhythms that cause difficulty in raising children, such as 1) frequently waking up, 2) difficulty falling asleep, 3) short sleep hours, and 4) continuous crying and grumpiness, were observed more often in ASD groups than in the control group. Additionally, the number of the mothers who went to bed after midnight during pregnancy was higher in the ASD groups than in the control group.

Sleep-wake rhythm abnormalities in neonates may be considerable precursors to future development of ASD. Formation of ultradian and postnatal circadian rhythms should be given more attention when considering ASD development. Although this is a retrospective study, the results suggest that a prospective study regarding this issue may be important in understanding and discovering intervention areas that may contribute to preventing and/or properly treating ASD.

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Neonatal irritable-type sleep-wake rhythmabnormalities are important precursors for futureASD development.

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Maternal lack of sleep and irregular lifestyle isrelated to increased risk of possibly developingfuture ASD.

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There is a possibility that proper intervention toabnormal sleep-wake rhythm may prevent thesubsequent onset of ASD.

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It is more logical to understand and interpret ASD,based on circadian rhythm and pineal glandfunction.

Inadequate sleep as a contributor to impaired glucose tolerance: A cross-sectional study in children, adolescents, and young adults with circadian rhythm sleep-wake disorder

BACKGROUND

Sleep deprivation and circadian disruption are associated with decreased insulin sensitivity and hyperglycemia. It is uncertain whether circadian sleep-wake disorder (CRSWD), which relates to both the homeostatic sleep system and the circadian timing system, affects glycemic regulation and insulin secretion. We aimed to examine the associations among sleep duration, sleep architecture or circadian rhythm of the sleep-wake cycle, and glucose metabolism in children, adolescents, and young adults with CRSWD.

METHODS

This cross-sectional observational study of 124 patients with CRSWD took place at Hyogo Children's Sleep and Development Medical Research Center in Hyogo, Japan. The patients underwent a 3-hour oral glucose tolerance test, anthropometric measurements, sleep-log analyses, and polysomnography. Analysis of covariance models were used to assess the association between sleep architecture or circadian rhythm of sleep-wake cycle and glucose/insulin homeostasis, adjusted for confounding variables such as age, gender, standardized body mass index, and sleep apnea index.

RESULTS

Impaired glucose tolerance was detected in 25.8% of all patients with CRSWD. After adjustment for confounding variables, we found a negative association between total sleep time (TST) and the 2-hour plasma glucose level. Stage N1 (%TST) was also a significant predictor of 3-hour glucose level. However, we did not detect an association between circadian rhythm of the sleep-wake cycle and glucose/insulin measures.

CONCLUSIONS

Decreased sleep duration and increased stage N1 (%TST) were associated with hyperglycemia in patients with CRSWD. Further research should elucidate how circadian misalignment in patients with CRSWD is associated with glucose and insulin homeostasis.

OSA and Cardiovascular Risk in Pediatrics

OSA occurs in approximately 1% to 5% of children in the United States. Long-term cardiovascular risks associated with OSA in the adult population are well documented. Although changes in BP regulation occur in children with OSA, the pathways leading to chronic cardiovascular risks of OSA in children are less clear. Risk factors associated with cardiovascular disease in adult populations could carry the same future risk for children. It is imperative to determine whether known mechanisms of cardiovascular diseases in adults are like those that lead to pediatric disease. Early pathophysiologic changes may lead to a lifetime burden of cardiovascular disease and early mortality. With this perspective in mind, our review discusses pathways leading to cardiovascular pathology in children with OSA and provides a comprehensive overview of recent research findings related to cardiovascular sequelae in the pediatric population.

Inadequate sleep as a contributor to type 2 diabetes in children and adolescents

Lack of sleep is a modifiable risk factor for adverse health in humans. Short sleep duration and poor sleep quality are common in the pediatric population; the largest decline in sleep duration over the past decades has been seen in children and adolescents. The objective of the present narrative review was to provide for the first time an overview of the literature on sleep and its association with type 2 diabetes mellitus (T2D) biomarkers in children and adolescents. For this narrative review, 23 studies were retained (21 observational and 2 experimental studies). Notwithstanding the conflicting results found in these studies and despite being attenuated by adiposity level, maturity, sex and age, there is still some compelling evidence for an association between sleep duration (for both objective or subjective measurements of duration) and architecture with one or more T2D biomarkers in children and adolescents. The majority of the studies reviewed did focus on sleep duration and one or more T2D biomarkers in children and adolescents, but sleep architecture, more precisely the suppression of slow wave sleep and rapid eye movement sleep, has also been shown to be associated with insulin resistance. Only two studies looked at sleep quality, and the association between sleep quality and insulin resistance was not independent of level of adiposity. Future experimental studies will help to better understand the mechanisms linking insufficient sleep with T2D. Work also needs to be carried out on finding novel and effective strategies aimed at improving sleep hygiene and health outcomes of children and adolescents.

Metabolic and glycemic sequelae of sleep disturbances in children and adults

The prevalence of obesity in adults and children has increased greatly in the past three decades, as have metabolic sequelae, such as insulin resistance and type 2 diabetes mellitus (T2DM). Sleep disturbances are increasingly recognized as contributors to this widespread epidemic in adults, and data are emerging in children as well. The categories of sleep disturbances that contribute to obesity and its glycemic co-morbidities include the following: (1) alterations of sleep duration, chronic sleep restriction and excessive sleep; (2) alterations in sleep architecture; (3) sleep fragmentation; (4) circadian rhythm disorders and disruption (i.e., shift work); and (5) obstructive sleep apnea. This article reviews current evidence supporting the contributions that these sleep disorders play in the development of obesity, insulin resistance, and T2DM as well as possibly influences on glycemic control in type 1 diabetes, with a special focus on data in pediatric populations.

Sex-specific associations between sleep problems and hypothalamic-pituitary-adrenocortical axis activity in children

STUDY OBJECTIVES

Sleep problems are associated with reduced physical and mental health. Altered function of the hypothalamic-pituitary-adrenocortical axis (HPAA) may be one underlying mechanism. We studied the associations between sleep problems and HPAA activity in children.

DESIGN

A cross-sectional epidemiological cohort study.

SETTING

Salivary cortisol was sampled throughout one day at home and during the Trier Social Stress Test for Children (TSST-C) in clinic. Sleep disorders were measured with a parent-rated Sleep Disturbance Scale for Children, and sleep duration measured by actigraphy for one week.

PARTICIPANTS

284 (51% girls) 8-year-old children.

RESULTS

Boys with sleep problems (≥ 85 th percentile in any of the sleep-wake transition, arousal, excessive daytime somnolence or sleep hyperhydrosis subscales) had lower diurnal salivary cortisol levels and salivary cortisol responses to TSST-C stress in comparison to boys without sleep problems. Girls with sleep problems (≥ 85 th percentile in disorders of initiating and maintaining sleep) displayed a higher overall level of salivary cortisol during the TSST-C. Salivary cortisol responses to stress were lower in boys and higher in girls with more than one sleep problem.

CONCLUSIONS

Sleep problems in children are associated with altered HPAA function, after controlling for actual sleep quantity measured by actigraphy. Boys with sleep problems had lower HPAA activity and girls with sleep problems had higher HPAA activity, compared to children without sleep problems.