Acute Sleep Restriction Reduces Insulin Sensitivity in Adolescent Boys

Racial and ethnic sleep health disparities in adolescents and risk for type 2 diabetes: a narrative review

INTRODUCTION

Sleep is an essential factor for health and wellbeing in people across the age spectrum; yet many adolescents do not meet the recommended 8-10 h of nightly sleep. Unfortunately, habitually insufficient sleep, along with the metabolic changes of puberty, puts adolescents at increased risk for a host of adverse health outcomes such as obesity and type 2 diabetes (T2D). Furthermore, individuals from historically minoritized racial and ethnic groups (e.g. Hispanic/Latinx, African American/Black) are more likely to experience shorter sleep duration compared to adolescents of White/European origin, placing them at even greater risk for disparities in T2D risk.

METHODS

We conducted a literature review on the role of race and ethnicity in adolescent sleep health and its relation to cardiometabolic outcomes, specifically T2D. We use the minority stress model and the stress and coping theory as guiding theoretical frameworks to examine individual and societal level factors that may contribute to sleep health disparities and their downstream effects on T2D risk.

RESULTS

This review highlights that the unique race-related stressors adolescents from minoritized groups face may play a role in the sleep and T2D connection on a biological, psychological, and social level. However, although there has been advancement in the current research on adolescent racial and ethnic sleep health disparities in relation to T2D, mechanisms underlying these disparities in sleep health need further investigation. Addressing these gaps is crucial for identifying and mitigating sleep health disparities and T2D among racial and ethnic minority youth.

CONCLUSION

We conclude with a discussion of the implications and future research directions of racial and ethnic disparities in sleep health and T2D prevention research. A comprehensive understanding of adolescent sleep health disparities has potential to better inform preventative and educational programs, interventions, and policies that promote sleep health equity and improve cardiometabolic outcomes like T2D.

Artificial Light at Night and Type 2 Diabetes Mellitus

The widespread and pervasive use of artificial light at night (ALAN) in our modern 24-hour society has emerged as a substantial disruptor of natural circadian rhythms, potentially leading to a rise in unhealthy lifestyle-related behaviors (e.g., poor sleep; shift work). This phenomenon has been associated with an increased risk of type 2 diabetes mellitus (T2DM), which is a pressing global public health concern. However, to date, reviews summarizing associations between ALAN and T2DM have primarily focused on the limited characteristics of exposure (e.g., intensity) to ALAN. This literature review extends beyond prior reviews by consolidating recent studies from 2000 to 2024 regarding associations between both indoor and outdoor ALAN exposure and the incidence or prevalence of T2DM. We also described potential biological mechanisms through which ALAN modulates glucose metabolism. Furthermore, we outlined knowledge gaps and investigated how various ALAN characteristics beyond only light intensity (including light type, timing, duration, wavelength, and individual sensitivity) influence T2DM risk. Recognizing the detrimental impact of ALAN on sleep health and the behavioral correlates of physical activity and dietary patterns, we additionally summarized studies investigating the potential mediating role of each component in the relationship between ALAN and glucose metabolism. Lastly, we proposed implications of chronotherapies and chrononutrition for diabetes management in the context of ALAN exposure.

Sleep Debt and Insulin Resistance: What's Worse, Sleep Deprivation or Sleep Restriction?

Objective  To evaluate which condition of sleep debt has a greater negative impact on insulin resistance: sleep deprivation for 24 hours or 4 hours of sleep restriction for 4 nights. Materials and Methods  In total, 28 healthy male subjects aged 18 to 40 years were recruited and randomly allocated to two groups: sleep deprivation (SD) and sleep restriction (SR). Each group underwent two conditions: regular sleep (11 pm to 7 am ) and total sleep deprivation for 24 hours (SD); regular sleep (11 pm to 7 am ) and 4 nights of sleep restriction (SR) (1 am to 5 am ). The oral glucose tolerance test (OGTT) was performed, and baseline glucose, insulin, free fatty acids (FFAs), and cortisol were measured. In addition, the area under the curve (AUC) for glucose and insulin, the homeostasis model assessment of insulin resistance (HOMA-IR), and the Matsuda Index (Insulin Sensitivity Index, ISI) were calculated. Results  Glucose and insulin had a similar pattern between groups, except at the baseline, when insulin was higher in the sleep debt condition of the SR when compared with the SD ( p  < 0.01). In the comparison between regular sleep and sleep debt, the SD had a higher insulin AUC ( p  < 0.01) and FFAs ( p  = 0.03) after sleep deprivation, and insulin and the insulin AUC increased ( p  < 0.01 for both), while the ISI decreased ( p  = 0.02) after sleep restriction in the SR. In baseline parameters covariate by the condition of regular sleep, insulin ( p  = 0.02) and the HOMA-IR ( p  < 0.01) were higher, and cortisol ( p  = 0.04) was lower after sleep restriction when compared with sleep deprivation. Conclusion  Sleep restriction for 4 consecutive nights is more detrimental to energy metabolism because of the higher insulin values and insulin resistance compared with an acute period of sleep deprivation of 24 hours.

Signals of energy availability in sleep: consequences of a fat-based metabolism

Humans can flexibly switch between two primary metabolic modes, usually distinguished by whether substrate supply from glucose can meet energy demands or not. However, it is often overlooked that when glucose use is limited, the remainder of energy needs may still be met more or less effectively with fat and ketone bodies. Hence a fat-based metabolism marked by ketosis is often conflated with starvation and contexts of inadequate energy (including at the cellular level), even when energy itself is in ample supply. Sleep and satiation are regulated by common pathways reflecting energy metabolism. A conceptual analysis that distinguishes signals of inadequate energy in a glucose-dominant metabolism from signals of a fat-based metabolism that may well be energy sufficient allows a reexamination of experimental results in the study of sleep that may shed light on species differences and explain why ketogenic diets have beneficial effects simultaneously in the brain and the periphery. It may also help to distinguish clinically when a failure of a ketogenic diet to resolve symptoms is due to inadequate energy rather than the metabolic state itself.

Normal Sleep in Children and Adolescence

Adequate sleep is essential for healthy development in childhood and adolescence. Healthy sleep contributes to good physical health, immune function, mental health, and academic performance. The regulation and architecture of sleep change greatly across childhood and adolescence, and the ability to obtain sufficient sleep is impacted by a range of factors that change with maturation. This article describes normal sleep across childhood and adolescence and discusses some of the most common barriers to adequate sleep, including early school start times, technology use, and changes to circadian rhythms, and sleep homeostasis across puberty.

Chrono-Nutrition: Circadian Rhythm and Personalized Nutrition

The human circadian system has a period of approximately 24 h and studies on the consequences of "chornodisruption" have greatly expanded. Lifestyle and environmental factors of modern societies (i.e., artificial lighting, jetlag, shift work, and around-the-clock access to energy-dense food) can induce disruptions of the circadian system and thereby adversely affect individual health. Growing evidence demonstrates a complex reciprocal relationship between metabolism and the circadian system, in which perturbations in one system affect the other one. From a nutritional genomics perspective, genetic variants in clock genes can both influence metabolic health and modify the individual response to diet. Moreover, an interplay between the circadian rhythm, gut microbiome, and epigenome has been demonstrated, with the diet in turn able to modulate this complex link suggesting a remarkable plasticity of the underlying mechanisms. In this view, the study of the impact of the timing of eating by matching elements from nutritional research with chrono-biology, that is, chrono-nutrition, could have significant implications for personalized nutrition in terms of reducing the prevalence and burden of chronic diseases. This review provides an overview of the current evidence on the interactions between the circadian system and nutrition, highlighting how this link could in turn influence the epigenome and microbiome. In addition, possible nutritional strategies to manage circadian-aligned feeding are suggested.

Effect of sleep disturbance on biomarkers related to the development of adverse health outcomes: A systematic review of the human literature

Literature suggests that unrestricted and undisturbed sleep is vital for basic human function and performance; however, it is unclear as to what amount of sleep disturbance leads to dysregulation in biomarkers, which may underscore the development of adverse health effects. This systematic review aims to identify the amount of sleep disturbance that contributes to biomarker changes as a potential precursor to the development of adverse health effects. English-language comparative studies available in PubMed, Cochrane Central, EMBASE, and CINAHL databases from 1 January 1980 to 31 July 2021 were searched. Where possible, random-effects meta-analyses were used to examine the effect of sleep disturbances on adverse health effects. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool and the Risk of Bias of Nonrandomised Studies - of Exposures instruments and the certainty of the body of evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. The search identified 92 primary studies reporting on blood pressure, hypertension, heart rate, cardiac arrhythmia, cardiac output, waist circumference, cortisol, adrenaline, noradrenaline, immune system markers, glucose, insulin, cholesterol, and triglyceride levels. Although some meta-analyses suggested there may be an association between sleep disturbances and certain outcomes, the certainty in the evidence was very low due to concerns with risk of bias, inconsistency across exposures, populations, and imprecision in the estimates of effects. Further research is needed to explore the point at which types, levels and duration of sleep disturbances may begin to increase the risk of developing adverse health outcomes to inform and tailor health interventions.

Randomized controlled trial to enhance children's sleep, eating, and weight

BACKGROUND

The present study assessed the efficacy of a behavioral intervention to enhance children's sleep and reduce caloric intake and body mass index (BMI) change.

METHODS

Seventy-eight children 8-11 years old who slept 9.5 h/night or less were randomized to the sleep intervention or to no treatment control. The primary outcome was 2-month change in the actigraph-estimated sleep period; changes in reported caloric intake, percent calories from fat, and BMI/BMI z-score (BMIz) were assessed.

RESULTS

Children randomized to intervention enhanced their sleep period by 40 ± 7 min/night relative to control (p < 0.001), and were more likely to increase their sleep period by 30 min/night or more (52% versus 15%, p = 0.003). No differences were observed for reported dietary intake or BMI/BMIz. However, in post-hoc analyses collapsing across groups, those who increased sleep by 30 min/night or more had lower BMI (-0.31 kg/m², p = 0.01) and BMIz (-0.07, p = 0.03) and reported fewer percent calories from fat at 2 months (-2.2%, p = 0.04).

CONCLUSIONS

A brief behavioral intervention can enhance children's sleep, but did not result in changes in caloric intake or weight status. Enhancing sleep by 30 min/night or more may be beneficial for weight regulation.

IMPACT

A brief behavioral intervention improved children's nocturnal sleep relative to no treatment control. Given the many benefits of a good night's sleep across domains of functioning, findings have significant implications for children's health and wellbeing. There were no differences between groups on eating behaviors or BMI. However, across groups, children who increased their sleep period by at least 30 min/night, reported reduced intake from fat and evidenced lower BMI at 2 months. Thus, a brief intervention can improve sleep and may have potential benefits for weight regulation.

Characteristic Sleep Patterns and Associated Obesity in Adolescents

Poor sleep adversely affects health and may cause obesity. Poor sleep includes short sleep duration, low quality of sleep, and sleep discrepancy. Although most studies have focused on the association between sleep duration and obesity, poor sleep is a significant risk factor for obesity. Adolescents have characteristic sleep patterns which correspond to poor sleep. Adolescents sleep late due to various biological and psychosocial factors; also, they wake up early to be on time for school. This causes them to sleep less. To make up for this sleep debt, adolescents sleep more on non-school days, which causes sleep discrepancies. Therefore, since adolescents have characteristic sleep patterns, an in-depth investigation is needed to identify whether poor sleep is a risk for obesity. This article presents an overview of the characteristic sleep patterns of adolescents, and reviews studies on the association of each sleep pattern with obesity.

Sleep optimization to improve glycemic control in adults with type 1 diabetes: study protocol for a randomized controlled parallel intervention trial

BACKGROUND

Despite improvements in treatment regimens and technology, less than 20% of adults with type 1 diabetes (T1D) achieve glycemic targets. Sleep is increasingly recognized as a potentially modifiable target for improving glycemic control. Diabetes distress, poor self-management behaviors, and reduced quality of life have also been linked to sleep variability and insufficient sleep duration. A significant gap of knowledge exists regarding interventions to improve sleep and the effects of sleep optimization on glycemic control in T1D. The purpose of this study is to determine the efficacy of a T1D-specific sleep optimization intervention (Sleep-Opt) on the primary outcomes of sleep variability, sleep duration, and glycemic control (A1C); other glycemic parameters (glycemic variability, time-in-range [TIR]); diabetes distress; self-management behaviors; quality of life; and other patient-reported outcomes in adults with T1D and habitual increased sleep variability or short sleep duration.

METHODS

A randomized controlled parallel-arm study will be employed in 120 adults (aged 18 to 65 years) with T1D. Participants will be screened for habitual sleep variability (> 1 h/week) or insufficient sleep duration (< 6.5 h per night). Eligible subjects will be randomized to the Sleep-Opt intervention group or healthy living attention control group for 12 weeks. A 1-week run-in period is planned, with baseline measures of sleep by actigraphy (sleep variability and duration), glycemia (A1C and related glycemic measures: glycemic variability and TIR using continuous glucose monitoring), and other secondary outcomes: diabetes distress, self-management behaviors, quality of life, and additional patient-reported outcomes. Sleep-Opt is a technology-assisted behavioral sleep intervention that we recently developed that leverages the rapidly increasing public interest in sleep tracking. Our behavioral intervention employs four elements: a wearable sleep tracker, didactic content, an interactive smartphone application, and brief telephone counseling. The attention control group will participate in a healthy living information program. Baseline measures will be repeated at midpoint, program completion, and post-program (weeks 6, 12, and 24, respectively) to determine differences between the two groups and sustainability of the intervention.

DISCUSSION

A better understanding of strategies to improve sleep in persons with T1D has the potential to be an important component of diabetes.

TRIAL REGISTRATION

Clinical Trial Registration: NCT04506151 .

Childhood diabetes and sleep

Sleep modulates glucose metabolism, both in healthy states and in disease. Alterations in sleep duration (insufficient and excessive) and obstructive sleep apnea may have reciprocal ties with obesity, insulin resistance and Type 2 diabetes, as demonstrated by emerging evidence in children and adolescents. Type 1 diabetes is also associated with sleep disturbances due to the influence of wide glycemic fluctuations upon sleep architecture, the need to treat nocturnal hypoglycemia, and the need for glucose monitoring and insulin delivery technologies. In this article, we provide an extensive and critical review on published pediatric literature regarding these topics, reviewing both epidemiologic and qualitative data, and provide an overview of the pathophysiology linking sleep with disorders of glucose homeostasis.

International society of sports nutrition position stand: tactical athlete nutrition

This position stand aims to provide an evidence-based summary of the energy and nutritional demands of tactical athletes to promote optimal health and performance while keeping in mind the unique challenges faced due to work schedules, job demands, and austere environments. After a critical analysis of the literature, the following nutritional guidelines represent the position of the International Society of Sports Nutrition (ISSN).

General Recommendations

Nutritional considerations should include the provision and timing of adequate calories, macronutrients, and fluid to meet daily needs as well as strategic nutritional supplementation to improve physical, cognitive, and occupational performance outcomes; reduce risk of injury, obesity, and cardiometabolic disease; reduce the potential for a fatal mistake; and promote occupational readiness.

Military Recommendations

Energy demands should be met by utilizing the Military Dietary Reference Intakes (MDRIs) established and codified in Army Regulation 40-25. Although research is somewhat limited, military personnel may also benefit from caffeine, creatine monohydrate, essential amino acids, protein, omega-3-fatty acids, beta-alanine, and L-tyrosine supplementation, especially during high-stress conditions.

First Responder Recommendations

Specific energy needs are unknown and may vary depending on occupation-specific tasks. It is likely the general caloric intake and macronutrient guidelines for recreational athletes or the Acceptable Macronutrient Distribution Ranges for the general healthy adult population may benefit first responders. Strategies such as implementing wellness policies, setting up supportive food environments, encouraging healthier food systems, and using community resources to offer evidence-based nutrition classes are inexpensive and potentially meaningful ways to improve physical activity and diet habits. The following provides a more detailed overview of the literature and recommendations for these populations.

Sympathetic neural responses to sleep disorders and insufficiencies

Short sleep duration and poor sleep quality are associated with cardiovascular risk, and sympathetic nervous system (SNS) dysfunction appears to be a key contributor. The present review will characterize sympathetic function across several sleep disorders and insufficiencies in humans, including sleep deprivation, insomnia, narcolepsy, and obstructive sleep apnea (OSA). We will focus on direct assessments of sympathetic activation, e.g., plasma norepinephrine and muscle sympathetic nerve activity, but include heart rate variability (HRV) when direct assessments are lacking. The review also highlights sex as a key biological variable. Experimental models of total sleep deprivation and sleep restriction are converging to support several epidemiological studies reporting an association between short sleep duration and hypertension, especially in women. A systemic increase of SNS activity via plasma norepinephrine is present with insomnia and has also been confirmed with direct, regionally specific evidence from microneurographic studies. Narcolepsy is characterized by autonomic dysfunction via both HRV and microneurographic studies but with opposing conclusions regarding SNS activation. Robust sympathoexcitation is well documented in OSA and is related to baroreflex and chemoreflex dysfunction. Treatment of OSA with continuous positive airway pressure results in sympathoinhibition. In summary, sleep disorders and insufficiencies are often characterized by sympathoexcitation and/or sympathetic/baroreflex dysfunction, with several studies suggesting women may be at heightened risk.

Adolescent sleep health and school start times: Setting the research agenda for California and beyond: A research summit summary: A research summit summary

In fall 2019, California passed and signed into law SB328, the first US statewide legislation explicitly designed to protect adolescent sleep health by requiring most California public school districts to start no earlier than 8:00 AM for middle schools and 8:30 AM for high schools. Recognizing the unique opportunity presented by the bill's 3-year implementation period, a group of experts in adolescent sleep and school start times held a virtual summit on January 22-23, 2021 to (1) summarize the research on adolescent sleep and school start time change; (2) develop recommendations for relevant, refined, and innovative research areas and research questions; (3) provide input regarding research design, methodology, and implementation; and (4) offer a forum for networking, exchanging ideas, and establishing interdisciplinary research collaborations. Participants represented a multidisciplinary range of academic backgrounds including sleep and circadian biology, neuroscience, education, medicine, public health, mental health, safety, public policy, economics, implementation science, criminology, diversity studies, and science communication. This paper summarizes summit presentations regarding current knowledge on adolescent sleep health and school start times and key research recommendations from small group workshops on topics including research design and tools, methodological issues, sleep health disparities, logistical challenges in conducting school-based research, public-health impact, and novel and expanded approaches to research.

Associations between Movement Behaviours and Obesity Markers among Preschoolers Compliant and Non-Compliant with Sleep Duration: A Latent Profile Analysis

This study identifies physical activity (PA) and sedentary behaviour (SB) clusters in preschoolers compliant (C) or non-compliant (NC) with sleep recommendations; and associates these clusters with obesity markers. PA and SB were objectively assessed (Actigraph WGT3-X) in 272 preschoolers (4.4 ± 0.7 years old). Sleep duration was parent-reported, and preschoolers were classified as C (3-4 years old: 600-780 min/day; 5 years old: 540-660 min/day) or NC with sleep recommendations. Body mass index (BMI) and waist circumference (WC) were assessed according to international protocols. Moderate to vigorous physical activity (MVPA) and light physical activity (LPA) were categorized as low/high (<60 min/>60 min/day or <180 min/180 min/day, respectively). SB was defined according to mean values between clusters. Latent profile analysis was performed. Associations between the observed clusters and obesity markers were determined using linear regression (RStudio; 1.3.1073). Four cluster solutions for C and NC preschoolers were identified. A negative association between C/Low MVPA cluster and BMI, and a positive association between NC/Low MVPA and BMI (β = -0.8, 95%CI = -1.6;-0.1, and β = 0.9, 95%CI = 0.1;1.7, respectively) were observed. No association was seen for SB clusters. Adequate sleep duration may have a protective role for preschoolers' BMI, even if the children do not comply with MVPA recommendations.

Effects of sleep intervention on glucose control: A narrative review of clinical evidence

BACKGROUND

Optimizing sleep has been recently gained exposure as a promising lifestyle consideration to aid in the control of diabetes. The evidence to support the impact of sleep quantity and quality on blood glucose control is largely acknowledged. This study aimed to review all published randomized controlled trials (RCTs) investigating the relationship between sleep and glucose control to synthesize an accurate overview.

METHOD

Literature from PubMed and Google Scholar was searched using the listed search terms to obtain RCTs on the role of sleep in glucose homeostasis. Seven RCTs were eligible and included in our review. References in these RCTs were screened for the presentation of the pathophysiology of metabolic disturbances relating to the sleep duration, and the relevant factors affecting blood glucose concentration.

RESULTS

Sleep deprivation and poor sleep quality are connected with blood glucose disturbance and reduction of insulin sensitivity. This leaves diabetic patients at an increased risk of glucose level fluctuations. However, the function of β-cells was likely to be conserved after 14-days of sleep deprivation. Sleep extension from 7 to 14 days improved blood glucose control and insulin sensitivity in both healthy and diabetes participants. Diabetes sleep education and personalized interventions that reduced stress and improved sleep quality contributed to glucose homeostasis in diabetic patients. Overall improving one's sleep hygiene was found to improve glucose control in diabetic patients.

CONCLUSION

Longer or short-term sleep deprivation may negatively affect glucose homeostasis, although the body temporarily compensates for the impaired function of β-cells when reduced sleep lasted up to 14 days. Thus, we recommend optimum sleep duration and optimistic sleep duration and sleep quality for decreasing risk and progression of diabetes.

The Association Between Sleep Duration and Sleep Timing and Insulin Resistance Among Adolescents in Mexico City

PURPOSE

Emerging evidence suggests that short sleep duration and delayed sleep timing may be independently related to insulin resistance (IR), although findings are mixed. Our aim was to investigate associations between sleep duration and timing with insulin resistance among adolescents.

METHODS

The analytic sample included 384 Mexican adolescents from a birth cohort study who took part in a follow-up study beginning in 2015. Insulin and glucose were measured in fasting serum, and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) was calculated (marker of insulin resistance; [insulin x glucose]/22.5). Sleep duration and midpoint were measured by actigraphy for 7 days after the visit and for analysis were separated by weekdays and weekends. In full and sex-stratified regression analysis, sleep duration and midpoint were exposures, and the log HOMA-IR was the outcome, adjusting for age.

RESULTS

The mean age of the sample was 13.8 ± 1.93 with 51% female. Shorter sleep duration on weekdays was associated with higher log HOMA-IR (β = -.049, 95% confidence interval [CI] -.097 to -.0009). Later midpoints on weekdays and the weekend were independently associated with higher log HOMA-IR (β = .0408, 95% CI -.0049 to .087, and β = .0486, 95% CI .0042 to .093, respectively). Girls showed stronger associations than boys for both sleep duration and timing with HOMA-IR.

CONCLUSIONS

Sleep duration and sleep timing were independently associated with insulin resistance, and associations were more pronounced among girls.

Actigraphic and patient and family reported sleep outcomes in children and youth with cystic fibrosis: A systematic review

BACKGROUND

Sleep concerns are commonly reported by children and youth with cystic fibrosis (CF). Understanding normative sleep in the home environment and as reported from the perspective of patients and parents is a first step in responding to an important clinical concern and developing a sleep intervention strategy. This systematic review aimed to describe actigraphic and self/parent reported measures of sleep quantity; quality; and determine factors associated with poor sleep quantity and/or quality in children and youth (0-25yrs.) with CF.

METHODS

Five online databases; Medline, Embase, CINAHL, PsycInfo, and CENTRAL were searched for relevant articles from inception-February 2020. Studies reporting primary data, using either qualitative/quantitative methods or both were eligible for inclusion. Eligible full text articles were independently screened by two reviewers. Data from included studies were independently extracted and synthesized by one reviewer and accuracy verified independently by a second reviewer.

RESULTS

This review found 31 articles that met inclusion criteria. Analysis found evidence demonstrating that actigraphic SE was lower, actigraphic nighttime awakenings were greater, and self/parent-reported measures of sleep quality were poorer in children and youth with CF. Study findings related to actigraphic TST, WASO, and self/parent-reported sleep duration were mixed. Thirteen factors demonstrated an association with poor quality sleep.

CONCLUSIONS

In children and youth with CF, evidence exists of objectively measured sleep disturbance and poor self/parent reported sleep quality. Further longitudinal and comparative research studies are warranted to better understand sleep disturbance in this population. Clinically, sleep assessment should be an integral part of routine CF care.

Disturbed sleep quality and architecture in adolescents with type 1 diabetes mellitus: Relation to glycemic control, vascular complications and insulin sensitivity

BACKGROUND

Insufficient sleep duration and poor sleep quality have been linked to insulin resistance and impaired glucose metabolism. However, the relation between sleep disruption and type1 diabetes (T1D) hasn't been thoroughly explored.

AIM

To study the association between sleep parameters and glycemic control, insulin resistance and micro-vascular complications among adolescent with T1D.

METHODOLOGY

Sixty adolescents with T1D were compared to 60 matched controls. Diabetes-duration, insulin-therapy, fundus, Epworth Sleepiness Scale-Child Adolescent and the neuropathy disability score were assessed. Fasting lipids, fraction-C of glycosylated hemoglobin(HbA1c) and urinary albumin-excretion were measured with calculation of the insulin sensitivity score(ISS). Overnight polysomnography(PSG) was done.

RESULTS

Adolescents with T1D had significantly lower sleep efficiency and rapid eye movement(REM) sleep than controls with significantly higher sleep onset latency, non-REM sleep and arousal index(P < 0.001). Although ISS was negatively correlated to total sleep time(P = 0.002); it was positively correlated to sleep efficiency(P < 0.001). HbA1C was negatively correlated to sleep efficiency(<0.001) and REM sleep(P = 0.003) and positively correlated to sleep onset latency(P = 0.005). T1D adolescents with micro-vascular complications had significantly lower sleep efficiency and REM sleep than those without micro-vascular complications.

CONCLUSION

Poor sleep quality and architecture among adolescents with T1D are associated with impaired glycemic control, insulin resistance and micro-vascular complications.

Circadian depression: A mood disorder phenotype

Major mood syndromes are among the most common and disabling mental disorders. However, a lack of clear delineation of their underlying pathophysiological mechanisms is a major barrier to prevention and optimised treatments. Dysfunction of the 24-h circadian system is a candidate mechanism that has genetic, behavioural, and neurobiological links to mood syndromes. Here, we outline evidence for a new clinical phenotype, which we have called 'circadian depression'. We propose that key clinical characteristics of circadian depression include disrupted 24-h sleep-wake cycles, reduced motor activity, low subjective energy, and weight gain. The illness course includes early age-of-onset, phenomena suggestive of bipolarity (defined by bidirectional associations between objective motor and subjective energy/mood states), poor response to conventional antidepressant medications, and concurrent cardiometabolic and inflammatory disturbances. Identifying this phenotype could be clinically valuable, as circadian-targeted strategies show promise for reducing depressive symptoms and stabilising illness course. Further investigation of underlying circadian disturbances in mood syndromes is needed to evaluate the clinical utility of this phenotype and guide the optimal use of circadian-targeted interventions.

A Model of Adolescent Sleep Health and Risk for Type 2 Diabetes

PURPOSE OF REVIEW

This paper presents a review of the current literature in support of a model explaining the relationships between sleep health and risk for type 2 diabetes in adolescents.

RECENT FINDINGS

Short sleep duration is associated with risk of developing obesity in youth. Sleep restriction increases energy expenditure, but also increases hunger, appetite, and food intake, causing positive energy balance, impacting appetite-regulating hormones, and leading to increased eating late at night. Insufficient sleep may lead to reduced physical activity and greater sedentary behaviors. In addition, short sleep duration is associated with reduced insulin sensitivity. The cumulative negative consequences of insufficient sleep increase risk for type 2 diabetes. Applications to clinical care, public policy, and future research are discussed. Insufficient sleep in adolescence increases risk for type 2 diabetes directly through impact on insulin sensitivity and indirectly through increased dietary intake, sedentary activity, and weight gain.

Normal Sleep in Children and Adolescence

Adequate sleep is essential for healthy development in childhood and adolescence. Healthy sleep contributes to good physical health, immune function, mental health, and academic performance. The regulation and architecture of sleep change greatly across childhood and adolescence, and the ability to obtain sufficient sleep is impacted by a range of factors that change with maturation. This article describes normal sleep across childhood and adolescence and discusses some of the most common barriers to adequate sleep, including early school start times, technology use, and changes to circadian rhythms, and sleep homeostasis across puberty.

Fear of hypoglycemia in patients with type 1 and 2 diabetes: a systematic review

AIMS AND OBJECTIVES

To summarize and thematize fear of hypoglycemia (FOH) in individuals with type 1 diabetes (T1D) and type 2 diabetes (T2D) to provide a theoretical basis for the development of effective interventions.

BACKGROUND

FOH is common in this population and can reduce quality of life(QOL) and adversely impact upon diabetes self-care management.

DESIGN

a systematic review METHODS: Articles published between 2000 and 2019 were searched in PubMed, MEDLINE, EMBASE, Web of Science and three Chinese databases (CNKI, Wan-fang data and VIP). Eligible articles were selected using the Preferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) guidelines. The quality of all articles finally included was evaluated by the Joanna Briggs Institute (JBI) Critical Appraisal tools.

RESULTS

Eighteen studies from 8654 papers were included. The sample size of each study ranged from 48 to 3812 subjects. FOH negatively impacted QOL, particularly psychosocial functioning, daily life and sleep quality.

CONCLUSIONS

FOH is a common and serious problem for patients, leading to poor QOL. It has been suggested that psychological concerns, QOL and effective countermeasures in individuals with T1D and T2D should be taken seriously. Advanced technology should be evaluated for its benefits before being used by patients.

RELEVANCE TO CLINICAL PRACTICE

The review highlights that FOH negatively impacts QOL, including psychosocial factors, daily life and sleep quality. Healthcare providers should develop targeted and professional assessment tools for FOH and QOL for patients with T2D, especially for patients who are about 60 years old. Advanced technology should be evaluated for its benefits before being used by patients.

Weekly variation in markers of cardiometabolic health - the possible effect of weekend behavior - a cross-sectional study

Background

Adolescents’ health-related behavior varies from weekday to weekend. Only few studies, however, have examined to which degree such variation will affect markers of cardiometabolic health. Therefore, the primary aim of this study is to examine if markers of cardiometabolic health differ between different days of the week in adolescents.

Methods

This cross-sectional school-based study included up to 581 participants, 11–17 years old. Markers of metabolic health were insulin, glucose, triglyceride, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and blood pressure. Linear mixed regression modelling was used to examine the cardiometabolic profile across weekdays.

Results

Significant declining trends were observed across the week in adolescents’ levels of cardiometabolic health markers. Lower levels of insulin (16.1%), glucose (2.6%) and triglyceride (24.7%) were observed on Fridays compared to Mondays (p ≤ 0.006). Gradual improvement in measurement profiles across weekdays was less apparent for HDL-C, LDL-C, systolic blood pressure and diastolic blood pressure (P ≥ 0.06). Analyses stratified by sex suggested a more noticeable pattern of gradual improvement across weekdays in boys than in girls.

Conclusion

Significantly lower levels of insulin, glucose and triglyceride were observed in adolescents on Fridays compared to Mondays. However, when sex specific analyses were performed significant profile variations were only observed across the week in boys. More research is needed to better understand which behavioral factors in particular seem to influence weekly variation in markers of cardiometabolic health - especially since such variation potentially will have an impact on how assessments of markers of cardiometabolic health optimally should be planned, standardized and carried out, both in research and in medical practice.

Associations between sleep duration and insulin resistance in European children and adolescents considering the mediating role of abdominal obesity

Background

Short sleep duration has been suggested to lead to insulin resistance both directly by altering glucose metabolism and indirectly through obesity. This study aims to investigate associations between nocturnal sleep duration and insulin resistance considering abdominal obesity as a mediator.

Methods

We analysed data of 3 900 children aged 2–15 years participating in the second (2009/10) and third (2013/14) examination wave of the European IDEFICS/I.Family study (hereafter referred to as baseline and follow-up). Information on nocturnal sleep duration was collected by questionnaires and age-standardised (SLEEP z-score). The homeostasis model assessment (HOMA) was calculated from fasting insulin and fasting glucose obtained from blood samples; waist circumference (WAIST) was measured with an inelastic tape. HOMA and WAIST were used as indicators for insulin resistance and abdominal obesity, respectively, and transformed to age- and sex-specific z-scores. Cross-sectional and longitudinal associations between SLEEP z-score and HOMA z-score were investigated based on a path model considering WAIST z-score as a mediator adjusting for relevant confounders.

Results

Cross-sectionally, baseline SLEEP z-score was negatively associated with baseline WAIST z-score (unstandardised effect estimate -0.120, 95% confidence interval [-0.167; -0.073]). We observed no direct effect of baseline SLEEP z-score on baseline HOMA z-score but a negative indirect effect through baseline WAIST z-score (-0.042 [-0.058; -0.025]). Longitudinally, there was no direct effect of baseline SLEEP z-score on HOMA z-score at follow-up but a negative indirect effect through both baseline WAIST z-score and WAIST z-score at follow-up (-0.028 [-0.040; -0.016]).

Conclusions

Our results do not support the hypothesis of an association between short sleep duration and insulin resistance independent of abdominal obesity. However, longer sleep duration may exert short and long term beneficial effects on insulin resistance through its beneficial effects on abdominal obesity.

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.

The immune-sleep crosstalk in inflammatory bowel disease

Sleep disorders are progressively common and sometimes are associated with aberrant regulation of the adaptive and innate immune responses. Sleep interruption can increase the inflammatory burden by enhancing the pro-inflammatory cytokines particularly in patients with chronic diseases such as inflammatory bowel disease (IBD). IBD is a chronic inflammatory disease characterized by immune dysregulation, dysbiosis of gut microbiome, and poor-quality life. Therefore, this review highlights the crosstalk between sleep and immune responses during the progression of IBD.

Differential effects of split and continuous sleep on neurobehavioral function and glucose tolerance in sleep-restricted adolescents

Study Objectives

Many adolescents are exposed to sleep restriction on school nights. We assessed how different apportionment of restricted sleep (continuous vs. split sleep) influences neurobehavioral function and glucose levels.

Methods

Adolescents, aged 15–19 years, were evaluated in a dormitory setting using a parallel-group design. Following two baseline nights of 9-hour time-in-bed (TIB), participants underwent either 5 nights of continuous 6.5-h TIB (n = 29) or 5-hour nocturnal TIB with a 1.5-hour afternoon nap (n = 29). After two recovery nights of 9-hour TIB, participants were sleep restricted for another three nights. Sleep was assessed using polysomnography (PSG). Cognitive performance and mood were evaluated three times per day. Oral glucose tolerance tests (OGTT) were conducted on mornings after baseline sleep, recovery sleep, and the third day of each sleep restriction cycle.

Results

The split sleep group had fewer vigilance lapses, better working memory and executive function, faster processing speed, lower level of subjective sleepiness, and more positive mood, even though PSG-verified total sleep time was less than the continuous sleep group. However, vigilance in both sleep-restricted groups was inferior to adolescents in a prior sample given 9-hour nocturnal TIB. During both cycles of sleep restriction, blood glucose during the OGTT increased by a greater amount in the split sleep schedule compared with persons receiving 6.5-hour continuous sleep.

Conclusions

In adolescents, modest multinight sleep restriction had divergent negative effects on cognitive performance and glucose levels depending on how the restricted sleep was apportioned. They are best advised to obtain the recommended amount of nocturnal sleep.

Trial registration

https://clinicaltrials.gov/ct2/show/NCT03333512

Sleep duration differentially affects brain activation in response to food images in adolescents with overweight/obesity compared to adolescents with normal weight

STUDY OBJECTIVES

Sleep is an important behavior that affects appetite and eating in adolescents. Our study examined food-related neural activation in brain regions associated with food reward and inhibition in adolescents under sleep-restricted and well-rested conditions.

METHODS

In this within-subjects study, 52 adolescents (ages 12-18; 46% female; M age = 15.96 years, SD = 1.56) with normal weight (NW; N = 29, M body mass index % [BMI%] = 54.55, SD = 24.54) or overweight/obesity (OV/OB; N = 23, M BMI% = 93.78, SD = 4.60) spent 5 hours in bed at home each night for five consecutive nights and 9 hours in bed at home each night for 5 consecutive nights, with the first day of each condition occurring 4 weeks apart. The morning following each sleep modification period, functional magnetic resonance imaging (fMRI) data were collected while participants performed an inhibitory (go/no-go) task with food stimuli.

RESULTS

We found significantly greater activation in brain regions associated with inhibition in adolescents with NW in response to food cues when sleep restricted. No increase in inhibition-related neural activation was observed in adolescents with OV/OB when sleep restricted. We also found neural activation consistent with greater reward processing associated with food cues following sleep restriction regardless of weight status.

CONCLUSIONS

These findings suggest that chronic sleep restriction may increase the likelihood of suboptimal dietary behavior for adolescents with OV/OB because they do not experience increased inhibition-related neural responding to counter possible increased reward-related neural responding following sleep restriction.

Impact of sleep deprivation and high-fat feeding on insulin sensitivity and beta cell function in dogs

AIMS/HYPOTHESIS

Insufficient sleep is increasingly recognised as a major risk factor for the development of obesity and diabetes, and short-term sleep loss in clinical studies leads to a reduction in insulin sensitivity. Sleep loss-induced metabolic impairments are clinically relevant, since reductions in insulin sensitivity after sleep loss are comparable to insulin sensitivity differences between healthy individuals and those with impaired glucose tolerance. However, the relative effects of sleep loss vs high-fat feeding in the same individual have not been assessed. In addition, to our knowledge no diurnal (active during the daytime) non-human mammalian model of sleep loss-induced metabolic impairment exists, which limits our ability to study links between sleep and metabolism.

METHODS

This study examined the effects of one night of total sleep deprivation on insulin sensitivity and beta cell function, as assessed by an IVGTT, before and after 9 months of high-fat feeding in a canine model.

RESULTS

One night of total sleep deprivation in lean dogs impaired insulin sensitivity to a similar degree as a chronic high-fat diet (HFD)(normal sleep: 4.95 ± 0.45 mU-1 l-1 min-1; sleep deprivation: 3.14 ± 0.21 mU-1 l-1 min-1; HFD: 3.74 ± 0.48 mU-1 l-1 min-1; mean ± SEM). Hyperinsulinaemic compensation was induced by the chronic HFD, suggesting adequate beta cell response to high-fat feeding. In contrast, there was no beta cell compensation after one night of sleep deprivation, suggesting that there was metabolic dysregulation with acute sleep loss that, if sustained during chronic sleep loss, could contribute to the risk of type 2 diabetes. After chronic high-fat feeding, acute total sleep deprivation did not cause further impairments in insulin sensitivity (sleep deprivation + chronic HFD: 3.28 mU-1 l-1 min-1).

CONCLUSIONS/INTERPRETATION

Our findings provide further evidence that sleep is important for metabolic health and establish a diurnal animal model of metabolic disruption during insufficient sleep.

Longitudinal Assessment of Sleep Trajectories during Early Childhood and Their Association with Obesity

Introduction: To identify longitudinal sleep trajectories in early childhood and examine the influence of sleep duration on obesity risk via BMI percentile (BMIp). Methods: Sleep, physical activity, and television viewing were measured in a cohort of 301 children, starting in 2001-2002, when children were 3 years and followed them through age 6. Nighttime sleep, daytime naps, and sleep duration were calculated. A series of latent growth curve models were used to estimate predictors of rate of change in sleep duration and BMIp overtime. A parallel process latent growth model examined the longitudinal relationship between sleep duration and BMIp simultaneously. Results: Most children (>80%) slept >10 hours per night across ages 3 to 6 years, despite the majority of children (>66%) having bedtimes after 9 pm. Sleep duration decreased on average by 0.22 (95% CI 0.20-0.24) hours each year of age (p < 0.001), while BMIp increased on average by 1.76 (95% CI 1.18-2.34) each year of age (p < 0.001). Baseline sleep duration predicted the BMIp slope factor, over and above strong effects of baseline BMIp. This indicated that greater sleep duration at baseline was predictive of decreased BMIp over time (unstandardized coefficient = -1.52 (95% CI 0.34-2.71, p = 0.012). Conclusions: Longer sleep duration at age 3 predicted decreased BMIp from ages 3 to 6. These findings indicate that focusing on sleep behaviors in children before age 3 may be a priority for pediatric providers with a goal of decreasing obesity risk.

A Novel Risk Score for Type 2 Diabetes Containing Sleep Duration: A 7-Year Prospective Cohort Study among Chinese Participants

BACKGROUND

Sleep duration is associated with type 2 diabetes (T2D). However, few T2D risk scores include sleep duration. We aimed to develop T2D scores containing sleep duration and to estimate the additive value of sleep duration.

METHODS

We used data from 43,404 adults without T2D in the Beijing Health Management Cohort study. The participants were surveyed approximately every 2 years from 2007/2008 to 2014/2015. Sleep duration was calculated from the self-reported usual time of going to bed and waking up at baseline. Logistic regression was employed to construct the risk scores. Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) were used to estimate the additional value of sleep duration.

RESULTS

After a median follow-up of 6.8 years, we recorded 2623 (6.04%) new cases of T2D. Shorter (both 6-8 h/night and <6 h/night) sleep durations were associated with an increased risk of T2D (odds ratio (OR) = 1.43, 95% confidence interval (CI) = 1.30-1.59; OR = 1.98, 95%CI = 1.63-2.41, respectively) compared with a sleep duration of >8 h/night in the adjusted model. Seven variables, including age, education, waist-hip ratio, body mass index, parental history of diabetes, fasting plasma glucose, and sleep duration, were selected to form the comprehensive score; the C-index was 0.74 (95% CI: 0.71-0.76) for the test set. The IDI and NRI values for sleep duration were 0.017 (95% CI: 0.012-0.022) and 0.619 (95% CI: 0.518-0.695), respectively, suggesting good improvement in the predictive ability of the comprehensive nomogram. The decision curves showed that women and individuals older than 50 had more net benefit.

CONCLUSIONS

The performance of T2D risk scores developed in the study could be improved by containing the shorter estimated sleep duration, particularly in women and individuals older than 50.

Saúde dos adolescentes da coorte de nascimentos de São Luís, Maranhão, Brasil, 1997/1998

Resumo: O objetivo foi estimar a prevalência de indicadores de saúde de adolescentes em São Luís, Maranhão, Brasil, em 2016. Foram estudadas condições sociodemográficas, hábitos de vida, composição corporal, qualidade do sono, atividade física, habilidade cognitiva e risco de suicídio de 2.515 adolescentes com 18 e 19 anos. Os adolescentes pertencem à coorte de nascimento 1997/1998 ou foram incluídos, retrospectivamente, utilizando-se o banco do SINASC (Sistema de Informações sobre Nascidos Vivos). Os adolescentes eram, principalmente, da classe econômica C (50,1%), 69,5% estudavam, 40,3% trabalhavam e 25,2% não estudavam nem trabalhavam; 60,3% já foram vítimas de assalto e 48,7% tinham pais separados. Apresentaram padrão de consumo nocivo, excessivo ou provável dependência de álcool 19,4%, 19,1% usaram ou estavam usando drogas ilícitas, 53,7% tinham qualidade de sono ruim, 40,8% referiram dor de cabeça frequente, 34,3% declararam tempo de tela por dia maior que cinco horas e 4,1% apresentaram alto risco para suicídio. A prevalência de hipertensão arterial foi de 12% e de obesidade, 6%. As meninas eram mais inativas (80,7%) e apresentaram maior percentual de gordura corporal alto (15,8%) e muito alto (21,5%), já os meninos tiveram maior prevalência de hipertensão arterial (21,2%) e menor prevalência de inatividade física (40,9%). As elevadas prevalências de fatores de risco à saúde aumentam a vulnerabilidade dos adolescentes, expondo estes indivíduos precocemente a fatores que levam ao acometimento cada vez mais cedo de doenças e agravos à saúde.

The association of sleep disturbances with glycemia and obesity in youth at risk for or with recently diagnosed type 2 diabetes

OBJECTIVE

Poor sleep may increase obesity and type 2 diabetes (T2D) risk in youth. We explored whether subjective sleep duration, sleep quality, or risk for obstructive sleep apnea (OSA) are associated with glycemia, body mass index (BMI), or blood pressure (BP) in overweight/obese youth.

METHODS

Two-hundred and fourteen overweight/obese youth of 10 to 19 years of age at risk for or recently diagnosed with T2D who were screened for the Restoring Insulin Secretion (RISE) Study had a 2-hour oral glucose tolerance test (OGTT) and completed a Cleveland Adolescent Sleepiness questionnaire and a Sleep Disturbances Scale questionnaire. Independent associations between sleep variables and measures of glycemia, BMI, and BP were evaluated with regression models.

RESULTS

The multiethnic cohort was 67% female, 14.1 ± 2.1 years, and BMI 35.9 ± 6.5 kg/m² . Habitual sleep duration <8 hours was reported in 74%. Daytime sleepiness was reported in 51%, poor sleep quality in 26%, and 30% had high obstructive sleep apnea (OSA) risk. Daytime sleepiness was associated with higher HbA1c (0.2%, P = .02) and 2-hour glucose (13.6 mg/dL, P < .05). Sleep duration, sleep quality, and OSA risk were not associated with the evaluated outcomes. Poor sleep quality and OSA risk were associated with higher BMI (2.9 kg/m² , P = .004 and 2.83 kg/m² , P < .003, respectively).

CONCLUSIONS

In overweight/obese youth with or at risk for T2D, daytime sleepiness was associated with higher HbA1c. In addition, poor sleep quality and OSA risk were associated with higher BMI. These findings support intervention studies aimed at improving sleep quality in obese youth.

Sleep Duration and Weight-Related Behaviors among Adolescents

Background: Insufficient sleep is widespread among adolescents and has consequences that extend far beyond hampering day-to-day functioning. It may influence eating and physical activity patterns and be an important determinant of adolescent overweight/obesity status. Methods: We assessed how self-reported sleep duration on school nights was associated with weight-related behaviors (eating, diet, and physical activity) and overweight/obesity at the baseline wave (ninth grade year) of the START study (n = 2134). Results: Fifteen percent of our sample reported optimal sleep duration (8.5-10.0 hours); nonwhites, participants of lower socioeconomic status, and girls were at greater risk for insufficient sleep. Suboptimal sleep was associated with various poor weight-related behaviors such as increased sugar-sweetened beverage consumption, decreased vegetable consumption, and decreased breakfast eating (p < 0.001). Fewer hours of sleep were also associated with less physical activity and an increased likelihood of obesity (p = 0.02 for both associations). Conclusions: The influence of adolescent sleep insufficiency on diet and activity could impact childhood obesity and following chronic disease risk especially if lack of sleep sets the stage for enduring, lifelong, poor, weight-related behavior patterns.

Poor sleep and adolescent obesity risk: a narrative review of potential mechanisms

Poor sleep is related to increased obesity risk in adolescents, though the mechanisms of this relationship are unclear. This paper presents a conceptual framework of the various pathways that have been proposed to drive this relationship. In this framework, increased food reward, emotional reactivity, decreased inhibitory control, metabolic disturbances, poorer dietary quality, and disrupted meal timings may increase the likelihood of increasing overall energy intake. This paper further notes how poor sleep increases sedentary behavior and screen time, which likely limits overall energy expenditure. The model posits that these mechanisms result in an imbalance of energy intake and expenditure following poor sleep, intensifying the overall risk for obesity. Increases in food reward processes, decreases in insulin sensitivity, disrupted meal timing, and increases in sedentary behavior seem to be the most compelling mechanisms linking poor sleep with increased obesity risk in adolescents. Future directions and clinical implications of this framework are discussed.

Timing Modulates the Effect of Sleep Loss on Glucose Homeostasis

CONTEXT

Chronobiological factors may modulate the impact of sleep loss on glucose homeostasis. However, these interactions have not been systematically assessed in humans.

OBJECTIVE

To assess the effect of sleep loss during the late vs early night on glucose homeostasis.

DESIGN

Fifteen normal-weight men participated in three conditions of a randomized, balanced crossover study comprising two conditions with shortened sleep (i.e., 4 hours of sleep during the first or the second half of the night) and a control condition with 8 hours of sleep. Glucose, insulin, cortisol, and glucagon were measured. Insulin sensitivity and secretion were assessed with a Botnia clamp.

RESULTS

Compared with regular sleep duration, sleep loss reduced insulin sensitivity (M-value; P = 0.031) irrespective of early- or late-night timing (P = 0.691). The disposition index (i.e., the β-cell response adjusted for insulin sensitivity) also tended to be impaired by short sleep (P = 0.056) but not by sleep timing (P = 0.543). In contrast, sleep loss in the second half but not the first half of the night induced reductions in morning glucagon and cortisol levels (P < 0.031) followed by a transient increase in cortisol (P < 0.044).

CONCLUSIONS

Although sleep deprivation acutely reduced insulin sensitivity irrespective of its nocturnal timing, sleep loss in the early morning compromised α-cell and hypothalamic-pituitary-adrenal axis activity to a greater extent than sleep loss in the first half of the night. This pattern suggests that the timing of sleep restriction can partly potentiate its deleterious metabolic effects.

Associations of sleep patterns with metabolic syndrome indices, body composition, and energy intake in children and adolescents

BACKGROUND

Self-reported short sleep duration is associated with greater risk for metabolic syndrome (MetS), obesity, and higher energy intake (EI). However, studies of these associations in children using objective methods are sparse.

OBJECTIVES

The study aims to determine the associations for sleep patterns with MetS indices, body composition, and EI using objective measures in children.

METHODS

Free-living sleep and physical activity were measured in 125 children (aged 8-17 years, BMI z = 0.57 ± 1.0, 55% female) using wrist-worn actigraphs for 14 nights. Blood pressure, fasting blood levels of lipids, insulin, glucose, waist circumference, and body composition (dual-energy X-ray absorptiometry [DXA]) were obtained during outpatient visits. EI was assessed during an ad libitum buffet meal.

RESULTS

Later weekday and weekend bedtimes were associated with higher systolic blood pressure (Ps < 0.05). Sleep duration and bedtime were not significantly associated with other components of MetS, body composition, or EI. Short sleepers (duration less than 7 hours) consumed a greater percentage of carbohydrates than those with adequate (greater than or equal to 7 hours) sleep (P < 0.05).

CONCLUSION

Indicators of sleep duration were variably associated with children's eating patterns and risk for chronic disease. Prospective data are needed to determine whether these indicators of sleep quality represent unique or shared risk factors for poor health outcomes.

Beneficial effects of a lifestyle intervention program on C-reactive protein: impact of cardiorespiratory fitness in obese adolescents with sleep disturbances

The objectives of this study were to assess the relationship between inflammation and obstructive sleep apnea (OSA) and determine whether the lifestyle program's effects on inflammatory markers are associated with changes in anthropometric parameters, cardiorespiratory fitness, sleep duration, and OSA severity in severely obese adolescents. Participants were aged 14.6 (SD 1.2) yr, with a body mass index (BMI) of 40.2 (SD 6.5) kg/m². Sleep, anthropometric parameters, glucose metabolism, inflammatory profile, and cardiorespiratory fitness [V̇o_2peak relative to body weight (V̇o_2peakBW) and fat-free mass (V̇o_2peakFFM)] were assessed at admission and at the end of a 9-mo lifestyle intervention program (LIP). Associations between C-reactive protein (CRP) concentrations and BMI, sex, oxygen desaturation index (ODI), sleep fragmentation, total sleep time (TST), and V̇o_2peak were assessed via ANCOVA. Twenty-three subjects completed the study. OSA subjects ( n = 13) exhibited higher CRP concentrations and a trend for higher BMI than non-OSA subjects ( P = 0.09) at admission. After intervention, OSA was normalized in six subjects, and CRP significantly decreased in the OSA group and in the whole population. In both groups, leptin levels significantly decreased, whereas adiponectin concentrations increased. At admission, BMI adjusted for sex, arousal index, ODI, TST, and V̇o_2peakBW was associated with CRP levels (adjusted r² = 0.32, P < 0.05). The decrease in CRP concentrations postintervention was associated with enhanced V̇o_2peakFFM adjusted for sex, weight loss, and changed sleep parameters (adjusted r² = 0.75, P < 0.05). Despite higher amounts of CRP in OSA subjects, obesity severity outweighs the proinflammatory effects of OSA, short sleep duration, and low cardiorespiratory fitness. However, enhanced cardiorespiratory fitness is associated with the decrease of inflammation after controlling for the same parameters.

Too Late and Not Enough: School Year Sleep Duration, Timing, and Circadian Misalignment Are Associated with Reduced Insulin Sensitivity in Adolescents with Overweight/Obesity

OBJECTIVES

To examine the relationship between insulin resistance (IR) and sleep/circadian health in overweight/obese adolescents. We hypothesized that insufficient and delayed sleep would be associated with IR in this population.

STUDY DESIGN

Thirty-one adolescents (mean age, 16.0 ± 1.4 years; 77% female) with body mass index ≥90th percentile for age/sex were recruited from outpatient clinics at a children's hospital. Participants underwent 1 week of objective home sleep monitoring with wrist actigraphy during the academic year. A 3-hour oral glucose tolerance test was conducted, followed by in-laboratory salivary dim-light melatonin sampling every 30-60 minutes from 5 p.m. to noon the next day. Regression analyses between sleep and circadian variables with IR were examined.

RESULTS

Longer sleep time and time in bed on weekends and weekdays and earlier weekday bedtime were significantly associated with better insulin sensitivity. Participants who obtained less than the median duration of sleep per night (6.6 hours) had evidence of IR with compensatory insulin secretion compared with those obtaining ≥6.6 hours of sleep. A wider phase angle between bedtime and melatonin onset, indicating a later circadian timing of sleep onset, was significantly associated with IR.

CONCLUSIONS

Short sleep duration, later weekday bedtime, and later circadian timing of sleep were associated with IR in a cohort of adolescents with overweight/obesity during the school year. Further research is needed to better understand the physiology underlying these observations and to evaluate the impact of improved sleep and circadian health on metabolic health in this at-risk population.

Association between Cluster of Lifestyle Behaviors and HOMA-IR among Adolescents: ABCD Growth Study

Objective: To analyze the association of potential risk factors to health with body fatness and insulin resistance. Baseline measures of the ongoing longitudinal Analysis of Behaviors of Children During (ABCD) Growth Study. Materials and Methods: The sample was composed of 280 adolescents of both sexes (198 boys and 82 girls) aged from 10 to 18 years. Four risk factors were considered, as follows: no sports practice, skipping breakfast, poor sleep quality, and TV viewing. The outcomes considered were insulin resistance (HOMA-IR) and body fatness (densitometer scanner). Age, sex, maturity offset, and ethnicity were treated as covariates. Results: No sports practice and skipping breakfast were associated with higher body fatness (Sports practice: Wald: 8.786; p = 0.003. Breakfast: Wald: 9.364; p = 0.002). Poor sleep quality was related to a greater HOMA-IR index (Wald: 6.013; p = 0.014). Adolescents with ≥3 risk factors presented a higher risk of high HOMA-IR (OR = 4.89 (95%CI: 1.61 to 14.84)) than their counterparts with no risk factors. Conclusion: Lifestyle risk factors seem relevant to affect obesity and insulin resistance, while the aggregation of these risk factors affects insulin resistance, independent of adiposity.

Association between Cluster of Lifestyle Behaviors and HOMA-IR among Adolescents: ABCD Growth Study

Objective: To analyze the association of potential risk factors to health with body fatness and insulin resistance. Baseline measures of the ongoing longitudinal Analysis of Behaviors of Children During (ABCD) Growth Study. Materials and Methods: The sample was composed of 280 adolescents of both sexes (198 boys and 82 girls) aged from 10 to 18 years. Four risk factors were considered, as follows: no sports practice, skipping breakfast, poor sleep quality, and TV viewing. The outcomes considered were insulin resistance (HOMA-IR) and body fatness (densitometer scanner). Age, sex, maturity offset, and ethnicity were treated as covariates. Results: No sports practice and skipping breakfast were associated with higher body fatness (Sports practice: Wald: 8.786; p = 0.003. Breakfast: Wald: 9.364; p = 0.002). Poor sleep quality was related to a greater HOMA-IR index (Wald: 6.013; p = 0.014). Adolescents with ≥3 risk factors presented a higher risk of high HOMA-IR (OR = 4.89 (95%CI: 1.61 to 14.84)) than their counterparts with no risk factors. Conclusion: Lifestyle risk factors seem relevant to affect obesity and insulin resistance, while the aggregation of these risk factors affects insulin resistance, independent of adiposity.

Association between Cluster of Lifestyle Behaviors and HOMA-IR among Adolescents: ABCD Growth Study

Objective: To analyze the association of potential risk factors to health with body fatness and insulin resistance. Baseline measures of the ongoing longitudinal Analysis of Behaviors of Children During (ABCD) Growth Study. Materials and Methods: The sample was composed of 280 adolescents of both sexes (198 boys and 82 girls) aged from 10 to 18 years. Four risk factors were considered, as follows: no sports practice, skipping breakfast, poor sleep quality, and TV viewing. The outcomes considered were insulin resistance (HOMA-IR) and body fatness (densitometer scanner). Age, sex, maturity offset, and ethnicity were treated as covariates. Results: No sports practice and skipping breakfast were associated with higher body fatness (Sports practice: Wald: 8.786; p = 0.003. Breakfast: Wald: 9.364; p = 0.002). Poor sleep quality was related to a greater HOMA-IR index (Wald: 6.013; p = 0.014). Adolescents with ≥3 risk factors presented a higher risk of high HOMA-IR (OR = 4.89 (95%CI: 1.61 to 14.84)) than their counterparts with no risk factors. Conclusion: Lifestyle risk factors seem relevant to affect obesity and insulin resistance, while the aggregation of these risk factors affects insulin resistance, independent of adiposity.

Reduced insulin sensitivity is correlated with impaired sleep in adolescents with cystic fibrosis

BACKGROUND

Prevalence of cystic fibrosis-related diabetes (CFRD) rises sharply in adolescence/young-adulthood and is associated with increased morbidity/mortality. Sleep may be a modifiable risk factor for diabetes but its relationship with metabolic function has not been fully examined in youth with CF. The aim of the study was to examine the relationship between objectively measured sleep and glucose metabolism in youth with CF.

METHODS

Adolescents (43 with CF and 11 healthy controls) completed 1-week of concurrent home continuous glucose monitoring (CGM) and actigraphy. Fasting labs and an oral glucose tolerance test were obtained. T-tests and analysis of variance (ANOVA) were used to test differences between actigraphy outcomes in CF participants and controls. Spearman's rank correlation coefficients were used to test for correlations between actigraphy, CGM, and insulin sensitivity (IS) measures.

RESULTS

All participants averaged insufficient sleep (mean = 7.5 hours per night) compared to the 8 to 10 hours recommended for this age group. CF participants had poorer sleep by actigraphy measures than healthy controls. Higher minimum daytime glucoses on CGM correlated with shorter total sleep time (TST) and worse sleep efficiency (SE). Reduced IS in CF participants with dysglycemia was correlated with shorter TST, longer sleep latency, more wake after sleep onset, and poorer SE.

CONCLUSIONS

Poor sleep appears to correlate with higher blood glucose and lower IS in CF adolescents with dysglycemia. Further research is needed to better understand the mechanisms and directionality behind this relationship.

Insufficient Sleep Duration Is Associated With Dietary Habits, Screen Time, and Obesity in Children

STUDY OBJECTIVES

To examine sleep duration and the association between insufficient sleep duration and life- style factors in a representative sample of Greek children and adolescents.

METHODS

Population data derived from a school-based health survey carried out in spring 2015 on 177,091 children (51% male) aged 8 to 17 years (participation rate was approximately 40% of the total population). Dietary habits, sleeping hours (weekdays and weekend), physical activity status, and sedentary activities were assessed through electronic questionnaires completed at school with assistance of teachers. Anthropometric and physical fitness measurements were obtained by physical education teachers.

RESULTS

A greater proportion of males than females (42.3% versus 37.3%, P < .001) and of children compared with adolescents (42.1% versus 32.8%, P < .001) reported insufficient sleep duration. Insufficient sleep duration was associated with unhealthy dietary habits such as skipping breakfast (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.25-1.35), fast-food consumption (OR 1.35, 95% CI 1.29-1.41), and consuming sweets regularly (OR 1.32, 95% CI 1.25-1.39). Insufficient sleep duration was found to be associated with insufficient dietary habits (OR 0.59, 95% CI 0.54-0.64), increased screen time (OR 1.26, 95% CI 1.21-1.31), and being overweight/obese (OR 1.21, 95% CI 1.17-1.25), after adjusting for several covariates.

CONCLUSIONS

Insufficient sleep duration was associated with an unhealthy lifestyle profile among children and adolescents in this study. Results support the development of interventions to help students improve sleep duration.

Prevalence and predictors of metabolically healthy obesity in adolescents: findings from the national "Jeeluna" study in Saudi-Arabia

BACKGROUND

Obese children and adolescents may vary with respect to their health profile, an observation that has been highlighted by the characterization of metabolically healthy obesity (MHO). The objectives of this study were to examine the prevalence of MHO amongst obese adolescents in Saudi-Arabia, and investigate the anthropometric, socio-demographic, and lifestyle predictors of MHO in this age group.

METHODS

A national cross-sectional school-based survey (Jeeluna) was conducted in Saudi-Arabia in 2011-2012 (n = 1047 obese adolescents). Anthropometric, blood pressure and biochemical measurements were obtained. A multicomponent questionnaire covering socio-demographic, lifestyle, dietary, psychosocial and physical activity characteristics was administered. Classification of MHO was based on two different definitions. According to the first definition, subjects were categorized as MHO based on the absence of the following traditional cardiometabolic risk (CR) factors: systolic blood pressure (SBP) or diastolic blood pressure (DBP) >90th percentile for age, sex, and height; triglycerides (TG) > 1.25 mmol/L; high density lipoprotein-cholesterol (HDL-C) ≤1.02 mmol/L; glucose ≥5.6 mmol/L. The second definition of MHO was based on absence of any cardiometabolic risk factor, according to the International Diabetes Federation (IDF) criteria.

RESULTS

The prevalence of MHO ranged between 20.9% (IDF) and 23.8% (CR). Subjects with MHO were younger, less obese, had smaller waist circumference (WC) and were more likely to be females. Based on stepwise logistic regression analyses, and according to the IDF definition, body mass index (BMI) (OR = 0.89, 95% CI: 0.84-0.93) and WC (OR = 0.97, 95% CI: 0.96-0.98) were the only significant independent predictors of MHO. Based on the CR definition, the independent predictors of MHO included female gender (OR = 1.76, 95% CI: 1.29-2.41), BMI (OR = 0.97, 95% CI: 0.94-1.00), and weekly frequency of day napping (OR = 1.06, 95% CI: 1.00-1.12). Analysis by gender showed that vegetables' intake and sleep indicators were associated with MHO in boys but not in girls.

CONCLUSION

The study showed that one out of five obese adolescents is metabolically healthy. It also identified anthropometric factors as predictors of MHO and suggested gender-based differences in the association between diet, sleep and MHO in adolescents. Findings may be used in the development of intervention strategies aimed at improving metabolic heath in obese adolescents.