Habitual Sleep Duration and Risk of Childhood Obesity: Systematic Review and Dose-response Meta-analysis of Prospective Cohort Studies

Racial/Ethnic Differences in the Age-Varying Association Between Adherence to 8-5-2-1-0 Guidelines in Adolescents with High BMI

PURPOSE

To examine the association between adherence to sleep, dietary, screen time, and physical activity (PA) (8-5-2-1-0) guidelines and risk of high body mass index (BMI ≥ 85 percentile) among U.S. adolescents and to assess for racial inequities and age-varying effects in these associations.

METHODS

Data from the 2019 Youth Risk Behavior Surveillance System survey were used to conduct multivariable logistic regression models and moderation analysis by race/ethnicity and age using time-varying varying effect models (TVEM) and estimate associations of interest.

RESULTS

Of the 13,518 adolescents aged ≥ 14 years, only 0.5% met all guidelines. Adolescents adhering to sleep guidelines had a 21% reduction in their odds of having a high BMI (OR 0.79, 95% CI 0.67-0.93). Those adhering to PA guidelines had a 34% reduction in their odds of having a high BMI (OR 0.66, 95% CI 0.56-0.79), and those adhering to screen time guidelines had a 17% reduction in their odds of having a high BMI (OR 0.83, 95% CI 0.72-0.95). TVEM showed associations between adherence to sleep and screen time guidelines with high BMI fluctuate and are at specific ages. TVEM revealed substantial racial/ethnic differences in the age-varying association between adherence to 8-5-2-1-0 guidelines and high BMI throughout adolescence.

CONCLUSIONS

Associations between adherence to sleep and screen time guidelines and high BMI fluctuate with age, highlighting the need for nuanced interventions targeting 24-h movement guidelines (sleep, PA, and screen time) across adolescence, particularly given racial/ethnic disparities.

Obesity in Adolescents: A Review

Importance

Obesity affects approximately 21% of US adolescents and is associated with insulin resistance, hypertension, dyslipidemia, sleep disorders, depression, and musculoskeletal problems. Obesity during adolescence has also been associated with an increased risk of mortality from cardiovascular disease and type 2 diabetes in adulthood.

Observations

Obesity in adolescents aged 12 to younger than 18 years is commonly defined as a body mass index (BMI) at the 95th or greater age- and sex-adjusted percentile. Comprehensive treatment in adolescents includes lifestyle modification therapy, pharmacotherapy, and metabolic and bariatric surgery. Lifestyle modification therapy, which includes dietary, physical activity, and behavioral counseling, is first-line treatment; as monotherapy, lifestyle modification requires more than 26 contact hours over 1 year to elicit approximately 3% mean BMI reduction. Newer antiobesity medications, such as liraglutide, semaglutide, and phentermine/topiramate, in combination with lifestyle modification therapy, can reduce mean BMI by approximately 5% to 17% at 1 year of treatment. Adverse effects vary, but severe adverse events from these newer antiobesity medications are rare. Surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy) for severe adolescent obesity (BMI ≥120% of the 95th percentile) reduces mean BMI by approximately 30% at 1 year. Minor and major perioperative complications, such as reoperation and hospital readmission for dehydration, are experienced by approximately 15% and 8% of patients, respectively. Determining the long-term durability of all obesity treatments warrants future research.

Conclusions and Relevance

The prevalence of adolescent obesity is approximately 21% in the US. Treatment options for adolescents with obesity include lifestyle modification therapy, pharmacotherapy, and metabolic and bariatric surgery. Intensive lifestyle modification therapy reduces BMI by approximately 3% while pharmacotherapy added to lifestyle modification therapy can attain BMI reductions ranging from 5% to 17%. Surgery is the most effective intervention for adolescents with severe obesity and has been shown to achieve BMI reduction of approximately 30%.

Earlier Bedtimes Mediate the Effect of a Brief Behavioral Sleep Intervention on Children's Weight Status

Whether the effect of a brief behavioral sleep intervention on child weight status resulted from observed differences in sleep duration and/or bedtimes was assessed. Findings demonstrate that the intervention's beneficial effect on weight regulation was due to earlier bedtimes, suggesting the potential importance of earlier bedtimes for obesity prevention.

A family-based and mobile-assisted intervention for lifestyle behaviors in youths: A randomized controlled trial

This randomized controlled trial was conducted to assess the effectiveness of a family-based and mobile-assisted lifestyle intervention in reducing weight gain among school-age children with overweight and obesity. A total of 164 school-age children with overweight or obesity and their parents were randomized to the treatment intervention (n = 82) or an attention-control group (n = 82). The treatment intervention included three face-to-face education sessions, augmented by monthly text messages sent to parents on their mobile devices. The primary outcome was child BMI-for-age z-score. Secondary outcomes included child BMI, percent body fat, and actigraphy-assessed sleep as well as parental sleep quality. Outcomes were assessed at baseline, 3, 6, and 12 months after the intervention, with treatment effects analyzed using general linear models for repeated measures. Our results showed that children in the treatment intervention group had significantly lower BMI-for-age z score, BMI, and percent body fat than did those in the control group, with an adjusted mean difference of 0.31 units (95% CI: -0.59 to -0.03; p = 0.03), 1.34 kg/m² (95% CI, -2.42 to -0.26; p = 0.01), and 3.12% (95% CI, -5.93 to -0.30; p = 0.03), respectively. No treatment effects were observed for child and parental sleep. Our findings suggest that family-based and mobile-assisted lifestyle intervention results in significant and sustained benefits to enhanced weight management for school-age children with overweight and obesity. Nurses planning and delivering childhood overweight and obesity treatment interventions should consider a family-based approach with the assistance of mobile devices.

"Your Kid Has Potential, But They Need Sleep": Teacher Perspectives on School-Based Sleep Promotion in Alberta, Canada

BACKGROUND

Insufficient sleep is a growing public health concern. Thirty percent of Canadian children and youth are not meeting national sleep recommendations. Inadequate sleep can negatively influence students' academics and physical and psychosocial health. Schools have been identified as ideal health promotion settings to influence children's health including their sleep behaviors. The objective of this study was to explore teachers' perspectives on sleep behaviors and their role in school-based sleep promotion.

METHODS

Nineteen elementary teachers were purposively sampled from the greater Edmonton area, Alberta, Canada. Interpretive description was used as the guiding method, and data were generated through one-on-one semi-structured interviews. Inductive descriptive thematic analysis was used to identify interview themes.

RESULTS

Three themes related to teachers' perspectives on sleep behaviors and school-based sleep promotion were identified: the importance of students' sleep, prioritizing sleep as part of teaching and learning, and a culture of healthy sleep habits.

CONCLUSIONS

This study found that teachers considered sleep to be essential for elementary students' academic success and wellbeing, and a whole school approach was necessary to support a healthy sleep culture in schools.

Effects of Early Wake-Up Time on Obesity in Adolescents

Background: Although numerous studies have reported that obesity in adolescents is related to shorter sleep duration, few studies have reported the effect of sleep timing, particularly early wake-up time, on obesity. Objectives: To investigate the association between wake-up time and adolescent obesity. Methods: Using the Korean National Health and Nutrition Examination Survey VII data, 1301 middle school and high school students were selected and grouped according to BMI. Sleep timing and lifestyle factors were evaluated using self-reported questionnaires. Results: The mean bedtime and wake-up time were 00:09 am and 07:06 am, respectively. Despite similar bedtimes, the group with overweight/obesity woke up earlier than the group with underweight/normal weight. The BMI z-score and the overweight/obesity relative risk decreased as the wake-up time was delayed, even after adjustment for covariates. Participants who woke up before 06:50 am had a 1.82-fold higher risk of having overweight/obesity than those who woke up after 07:30 am. Participants who woke up late tended to sleep longer than those who woke up early. Conclusions: Waking up early is significantly associated with an increased BMI z-score in adolescents and may be a risk factor for overweight/obesity.

The cross-sectional and prospective associations of parental practices and environmental factors with 24-hour movement behaviours among school-aged Asian children

BACKGROUND

Parental practices and neighbourhood environmental factors may influence children's movement behaviours. We aimed to investigate the cross-sectional and prospective associations of parental practices and neighbourhood environmental factors with accelerometer-measured 24-hour movement behaviours (24 h-MBs) among school-aged children in Singapore.

METHODS

The Growing Up in Singapore Towards healthy Outcomes (GUSTO) study collected information on dimensions of parental practices and neighbourhood environment at age 5.5 years. Confirmatory factor analyses were performed to generate latent variables and used to compute overall parental practices [involvement in PA + support for PA + control of screen viewing context] and environmental scores [facilities for active play + active mobility facilitators + barriers*-1]. Children wore an accelerometer on their non-dominant wrist for seven consecutive days at ages 5.5 and 8 years. The R-package GGIR 2.6 was used to derive moderate-to-vigorous-intensity physical activity (MVPA), light-intensity physical activity (LPA), inactivity, and total-sleep (napping+night sleep) minutes per day. Associations were determined using compositional data analysis with multivariate linear regression models, taking into account potential confounders.

RESULTS

Among 425 children (48% girls, 59% Chinese), higher parental involvement in PA, parental support for PA and overall parental practices were associated with 24 h-MBs at ages 5.5 and 8 years, specifically with greater time spent in MVPA and less time being inactive relative to the remaining movement behaviours. The corresponding mean changes in the overall 24 h-MB for increasing parental practices from lowest to highest scores (- 2 to + 2 z-scores) indicated potential increases of up to 15-minutes in MVPA, 20-minutes in LPA, 5-minutes in sleep duration, and a reduction of 40-minutes in inactivity at age 5.5 years. At age 8 years, this could translate to approximately 15-minutes more of MVPA, 20-minutes more of LPA, a 20-minute reduction in sleep duration, and a 20-minute reduction in inactivity. Parental control of screen viewing contexts and neighbourhood environmental factors were not associated with 24 h-MBs.

CONCLUSIONS

Parental practices but not environmental factors were associated with higher MVPA and lower inactivity among Singaporean children, even at a later age. Further research may provide insights that support development of targeted public health strategies to promote healthier movement behaviours among children.

STUDY REGISTRATION

This study was registered on 4th August 2010 and is available online at ClinicalTrials.gov: NCT01174875.

Validation of the Malay version of Epworth sleepiness scale for children and adolescents (MESS-CHAD)

BACKGROUND

Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) is a valid and reliable eight-item self-administered questionnaire for the assessment of excessive daytime sleepiness and is commonly used to screen sleep-disordered breathing for children and adolescents. The cross-sectional study aimed to translate and cross-culturally adapt ESS-CHAD into a Malay version of Epworth Sleepiness Scale for Children and Adolescents (MESS-CHAD) for the Malaysian population, and to assess the validity and reliability of MESS-CHAD.

METHODS

Forward-backward translation method was used to translate and cross-culturally adapt ESS-CHAD. Three linguistic experts and two paediatricians content validated the translated version. Face validity was conducted through audio-recorded semi-structured in-depth interviews with 14 native Malay-speaking children and adolescents followed by thematic analysis. The revised questionnaire was then proofread by a linguistic expert. A total of 40 subjects answered the MESS-CHAD twice, 2 weeks apart, for test-retest reliability and internal consistency. For criterion validity, 148 eligible subjects and their parents answered MESS-CHAD and the Malay version of Sleep-Related Breathing Disorder scale extracted from the Paediatric Sleep Questionnaire (M-PSQ:SRBD) concurrently. Variance Inflation Factor (VIF) and P values of the model's outer weight and outer loading were analysed using SmartPLS software to assess the indicator's multicollinearity and significance for formative construct validity.

RESULTS

Intraclass Correlation Coefficient (ICC) ranging from 0.798 to 0.932 and Cronbach's alpha ranging from 0.813 to 0.932 confirmed good to excellent test-retest reliability and internal consistency, respectively. Spearman Correlation Coefficient value of 0.789 suggested a very strong positive correlation between MESS-CHAD and M-PSQ:SRBD. VIF ranging from 1.109 to 1.455 indicated no collinearity problem. All questionnaire items in MESS-CHAD were retained as the P value of either outer model weight or outer model loading was significant (P < 0.05).

CONCLUSION

ESS-CHAD has been translated and cross-culturally adapted into Malay version for the Malaysian population, and found to be valid and reliable.

The Longitudinal Interplay between Sleep, Anthropometric Indices, Eating Behaviors, and Nutritional Aspects: A Systematic Review and Meta-Analysis

Sleep is fundamental for adolescents' healthy development but undergoes dramatic changes in quantity and quality due to the conflict between biological and social rhythms. Insufficient sleep has been associated with worse physical health status and irregular eating behaviors in adolescents. This review aims to systematically synthesize the longitudinal associations between adolescents' sleep dimensions (i.e., duration, timing, quality, and insomnia symptoms) and physical health indicators (i.e., anthropometric indices, fat percentage, and risk of obesity), eating behaviors, and nutritional aspects (i.e., type of diet related to the intake of specific foods and nutrients, amount and timing of food consumption, energy expenditure). A total of 28 longitudinal studies were included. The meta-analytic results showed that longer sleep duration, better sleep quality, and lower insomnia symptoms were associated with lower BMI and fat percentage and that shorter sleep duration (<7 h) and lower sleep quality were associated with a higher risk of obesity. Conversely, anthropometric indices were not related to sleep over time. Limited literature examined the bidirectional association between adolescents' sleep and their eating behaviors and nutritional aspects. Such knowledge sheds new light on the role of sleep for adolescents' health, highlighting the need to examine further the interplay between these variables.

Sleep Well, Study Well: A Systematic Review of Longitudinal Studies on the Interplay between Sleep and School Experience in Adolescence

Adolescents spend most of their daily time in school and performing school-related activities. Different aspects of their school experiences, such as school performance, psychological factors related to school, and structural factors, consistently impact adolescents' health and are likely to be intertwined with their sleep (i.e., quantity and quality, sleep disturbances). This systematic review aimed to comprehensively summarize the reciprocal and longitudinal associations between adolescents' sleep and multiple aspects of their school experience. Using multiple search strategies and applying a two-step selection process, 25 journal articles matched the eligibility criteria and were thus included in the review. The results highlighted the contribution of poor sleep quality and sleep disturbances in predicting longitudinal school experiences-related outcomes (i.e., decreasing school engagement and performance, and increasing school-related burnout, absenteeism, and bullying). At the same time, the results showed how experiences related to the school's psychological factors (e.g., high levels of school burnout and stressful environment) and structural characteristics (e.g., early school entrance time) affect youth sleep over time (i.e., decreasing sleep quality and quantity). These main findings provided novel insights into the bidirectional relationship between school experience and sleep health, highlighting the importance of more longitudinal research investigating all aspects of healthy sleep, including the size and direction of the association.

Sleep Is a Family Affair: A Systematic Review and Meta-Analysis of Longitudinal Studies on the Interplay between Adolescents' Sleep and Family Factors

Family is one of the primary socialization contexts influencing adolescents' psychological health. In this regard, a crucial indicator of adolescents' health is their sleep quality. Nevertheless, it is still unclear how multiple family factors (i.e., demographic and relational) are intertwined with adolescents' sleep quality. For this reason, this systematic review with meta-analysis aims to comprehensively summarize and integrate previous longitudinal research investigating the reciprocal relation between demographics (e.g., family structure) and positive (e.g., family support) and negative (e.g., family chaos) relational family factors and adolescents' sleep quality. Several search strategies were applied, and a final set of 23 longitudinal studies that matched the eligibility criteria were included in this review. The total number of participants was 38,010, with an average age at baseline of 14.7 years (SD = 1.6, range: 11-18 years). On the one hand, the meta-analytic results showed that demographic factors (e.g., low socio-economic status) were not related to adolescents' sleep quality at a later time point. On the other hand, positive and negative family relational factors were positively and negatively related to adolescents' sleep, respectively. Furthermore, the results suggested that this association could be bidirectional. Practical implications and suggestions for future research are discussed.

Recreational screen time trajectories during early childhood and imaging-measured body composition at age 7 in the Odense child cohort

BACKGROUND

Children spend increasing amounts of time on recreational screen media, which may lead to an obesogenic environment.

OBJECTIVES

We investigated the association of trajectories of screen time across ages 3, 5 and 7 years with body composition at age 7 in the Odense Child Cohort.

METHODS

Data were collected in the Municipality of Odense, Denmark, between 2010 and 2019. Group-based trajectory modelling was applied to group participants into four trajectories of prospective parent-reported screen time. Body composition was assessed using dual-energy x-ray absorptiometry with calculated fat-mass index (FMI) as the primary outcome. Primary models were linear multivariable regression models adjusted for participants' sex, age, birthweight, maternal origin, maternal education, maternal body-mass-index, and maternal age. Further models were adjusted for additional possible confounders. Selection bias was addressed by inverse probability weighting.

RESULTS

In total, 803 children (48.2% female) were included in the primary analysis. Participants with screen time at all time points were assigned to four trajectory groups [constant low screen time (12.7%), low increase (36.3%), high increase between ages 3 and 5 (33.5%) and high increase in screen time (17.5%)]. Sample characteristics differed across missing data status and trajectories. Mean FMI (kg/m² ) and standard deviation (SD) were 3.7 (SD 1.3) and 3.9 (SD 1.6) for the constant low versus high screen time, respectively. No differences in FMI were found between screen time trajectory groups at age 7 (adjusted mean difference 0.1 kg/m² , 95% confidence interval -0.3, 0.5 for constant low versus high screen time). No consistent associations between screen time groups and secondary body composition outcomes were found.

CONCLUSIONS

Results from this study do not suggest that recreational screen time from age 3 to 7 years is associated with adiposity or other measures of body composition.

Self-reported physical activity behaviors of childhood cancer survivors: comparison to a general adolescent population in Korea

PURPOSE

Adequate physical activity (PA) can significantly contribute to the prevention of undesirable health outcomes in childhood cancer survivors (CCS). This study aimed to identify the patterns of PA and related factors in Korean CCS.

METHODS

Study subjects were 184 adolescents selected from an ongoing cohort study of Korean CCS and 1,840 sex- and school grade-matched controls randomly selected from the participants of the 2019 Korea Youth Risk Behavior Web-based Survey. Information on PA and sedentary behaviors was collected by self-administered questionnaire. We estimated body mass index (BMI)-adjusted odds ratio (OR) and 95% confidence interval (CI) for the advisable healthy behaviors of CCS compared with healthy controls using conditional logistic regression analysis. In addition, the associations of advisable healthy behaviors of CCS with sociodemographic and clinical factors were estimated using multiple logistic regression analysis.

RESULTS

CCS were less likely to be physically active than controls, but this finding was evident only in males. The ORs (95% CIs) for regular exercise, moderate intensity PA, vigorous intensity PA, and walking were 0.42 (0.27-0.65), 0.39 (0.24-0.63), 0.53 (0.33-0.84), and 0.64 (0.42-0.98), respectively, in male CCS compared with same-sex controls. Compared with same-sex controls, male CCS were 4.60 times and female survivors were 15.19 times more likely to sleep longer than 8 h a day. Among CCS, males were 2.92 times and 3.07 times more likely to perform moderate intensity PA and muscle-strengthening exercise, respectively, than female. Higher BMI (OR: 1.16), highest family income (OR: 3.98), and a caregiver who performed regular exercise (OR: 2.08) were positively associated with vigorous intensity PA of CCS. With increasing time after treatment completion, the probability of engaging in sedentary activity for less than 6 h per day decreased (OR = 0.89, 95% CI 0.79-1.00).

CONCLUSION

Korean adolescent CCS were physically inactive compared with control adolescents. Several sociodemographic factors such as sex, family income, caregiver PA, and obesity level were associated with PA behaviors of CCS.

IMPLICATIONS

Strategic effort would be needed to increase physical activity of childhood cancer survivors in adolescent period with consideration of various sociodemographic factors found in this study.

The Social Side of Sleep: A Systematic Review of the Longitudinal Associations between Peer Relationships and Sleep Quality

In adolescence, peer relationships become crucial since youths start to rely on their peers for support. Thus, multiple facets of adolescents' well-being are affected by their peer relationships. In this vein, one of the central well-being aspects that could be affected by the peer relationships of adolescents is sleep quality. Nevertheless, it is still unclear how multiple peer relationship factors (i.e., positive, negative, emotional, and behavioral issues related to peer relationships) are intertwined with adolescents' sleep quality. For this reason, this systematic review with meta-analysis aims to summarize longitudinal studies to uncover how the interplay between peer relationship factors and adolescents' sleep quality unfolds over time. Nineteen longitudinal studies involving a total of 21,232 adolescents were included. Overall, findings from this review showed that (a) positive peer relationships and sleep quality were not associated over time; (b) negative peer relationships and sleep quality were bidirectionally associated over time; (c) few studies evaluated the bidirectional relations between emotional and behavioral issues and sleep quality, showing links with sleep schedule and duration, but not with sleep quality. Meta-analytic results were discussed, considering their implications.

Promoting Sleep Duration in the Pediatric Setting Using a Mobile Health Platform: A Randomized Optimization Trial

Objective

Determine the optimal combination of digital health intervention component settings that increase average sleep duration by ≥30 minutes per weeknight.

Methods

Optimization trial using a 25 factorial design. The trial included 2 week run-in, 7 week intervention, and 2 week follow-up periods. Typically developing children aged 9-12y, with weeknight sleep duration <8.5 hours were enrolled (N=97). All received sleep monitoring and performance feedback. The five candidate intervention components (with their settings to which participants were randomized) were: 1) sleep goal (guideline-based or personalized); 2) screen time reduction messaging (inactive or active); 3) daily routine establishing messaging (inactive or active); 4) child-directed loss-framed financial incentive (inactive or active); and 5) caregiver-directed loss-framed financial incentive (inactive or active). The primary outcome was weeknight sleep duration (hours per night). The optimization criterion was: ≥30 minutes average increase in sleep duration on weeknights.

Results

Average baseline sleep duration was 7.7 hours per night. The highest ranked combination included the core intervention plus the following intervention components: sleep goal (either setting was effective), caregiver-directed loss-framed incentive, messaging to reduce screen time, and messaging to establish daily routines. This combination increased weeknight sleep duration by an average of 39.6 (95% CI: 36.0, 43.1) minutes during the intervention period and by 33.2 (95% CI: 28.9, 37.4) minutes during the follow-up period.

Conclusions

Optimal combinations of digital health intervention component settings were identified that effectively increased weeknight sleep duration. This could be a valuable remote patient monitoring approach to treat insufficient sleep in the pediatric setting.

Epidemiology of Sleep Disorders Among Adolescents in Kerman, Iran, in 2019

It is an important fact that the onset of adolescence is a time of both physiological and social changes that affect sleep. In this study, the prevalence of sleep disorders in adolescents and the association between them were investigated. Anthropometric dimensions (such as height and weight) of individuals in Kerman in 2019 were also assessed. A total of 451 adolescents (mean age: 14.72 years; 51.88% females) of Kerman, Iran, took part in this cross-sectional study. Participants completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire, and then demographic (age, gender) and anthropometric data (weight and height) were collected. The prevalence of sleep disorders in this population was 31.9%. Among those with self-rated sleep disorders, 53.5% were males. Participants with sleep disorders were younger and showed lower anthropometric values such as height, weight, and body mass index. However, there was no difference between sleep disorders and gender (P-value > .05). This study revealed a relatively high prevalence of sleep disorders among adolescents. This research was done with the aim of encouraging the healthcare organization to design educational programs to evaluate and reduce sleep disorders.

Risk of Severe COVID-19 in Non-Adherent OSA Patients

Background

Patients with obstructive sleep apnoea (OSA) are at increased risk of severe course of COVID-19. Vaccination remains to be the most effective prevention of complicated courses of infection. The best contemporary conservative treatment of OSA is continuous positive airway pressure (CPAP) therapy.

Purpose

To compare vaccination acceptance and outcomes of COVID-19 infection between OSA patients adhering to the CPAP therapy and those who rejected CPAP and surgical therapy.

Patients and Methods

Subjects were divided into two groups: group A (N = 167) were individuals with sufficient CPAP adherence (more than 4 hours per night on average) over the last 10 years. Group B (N = 106) were individuals who did not use the CPAP therapy at all and had no indications to surgical therapy.

Results

Three patients in group B died, and one had a severe course of COVID-19. None of the patients in group A died or experienced a severe course of COVID-19. Group A had a significantly higher proportion of males (77.8% compared to 66% in group B) and all parameters of OSA severity. The vaccination status was similar among both groups, with a complete triple dose vaccination rate of 69.5% and 67.9% in groups A and B, respectively.

Conclusion

The results show that the patients with OSA adherent to CPAP therapy were less likely to experience a severe course of COVID-19 or death than the OSA patients non-compliant with therapy, despite the former group having more severe OSA. This result underlines the importance of adherence to CPAP therapy in OSA.

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.

Application of a composite scoring protocol to identify factors that contribute to the risk of overweight and obesity in Irish children

BACKGROUND

Investigations into the main drivers of childhood obesity are vital to implement effective interventions to halt the global rise in levels. The use of a composite score may help to identify children most at risk of overweight/obesity.

OBJECTIVES

To investigate the cumulative impact of factors associated with overweight/obesity risk in children.

METHODS

Data were analysed from the Irish National Children's Food Survey II which included 600 children, aged 5-12-years. The risk factors examined included social class, parental, early life, lifestyle, and dietary components. A composite score was calculated which ranged from 0 (no risk factors for overweight/obesity) to 4 (4 risk factors for overweight/obesity).

RESULTS

In model 1 (%BF) the four factors associated with overweight/obesity risk were having a parent with overweight/obesity (odds ratio 3.1; 95% confidence interval 1.9-4.8), having a high birth weight of ≥4 kg (2.5; 1.6-3.9), being from a low social class (2.3; 1.4-3.8) and low physical activity (1.9; 1.2-2.8). Children who scored 3-4 points on the composite score had a 10-fold (10.0; 4.2-23.9) increased risk of overweight/obesity compared to those with 0 points, a sevenfold (7.2; 3.9-13.5) increased risk compared to those with 1 point and a threefold (2.6; 1.4-4.8) increased risk compared to those with 2 points, with similar results observed in model 2 (BMI).

CONCLUSION

The use of a composite score is a beneficial means of identifying children at risk of overweight/obesity and may prove useful in the development of effective interventions to tackle childhood obesity.

Sleep duration of lactating mothers and its relationship with feeding pattern, milk macronutrients and related serum factors: A combined longitudinal cohort and cross-sectional study

Objective

Insufficient sleep is common in postpartum mothers. The main objectives of this study are to explore the sleep duration among Chinese lactating mothers and preliminarily investigate the relationship between sleep duration and feeding pattern. The secondary objectives are to investigate the relationships between sleep duration and milk macronutrients and between maternal-related indicators, including melatonin (MT), growth hormone (GH), ghrelin (GHRL), glucagon-like peptide-1 (GLP-1), prolactin (PRL), and cholecystokinin (CCK).

Methods

The present study comprises a longitudinal and a cross-sectional cohort from December 2019 to December 2021. Postpartum lactating women living in Shanghai were recruited through online and offline recruitment. The subjects were included in the longitudinal cohort or cross-sectional study based on their lactation period at the time of recruitment. The longitudinal cohort included a total of 115 mothers. Human milk and feeding pattern were measured and collected at 2–4 months and 5–7 months postpartum. At four predetermined follow-up time points, data on sleep duration was collected (at the time of recruitment, 2–4 months postpartum, 5–7 months postpartum, and 12–17 months postpartum). The cross-sectional study included 35 lactating mothers (2–12 months postpartum) who reported their sleep duration and provided blood samples. Mid-infrared spectroscopy (MIRS) method was used to analyze the macronutrients of breast milk, while MT, GH, GHRL, GLP-1, PRL, and CCK in maternal blood were determined by ELISA.

Results

The maternal sleep duration before pregnancy was 8.14 ± 1.18 h/d (n = 115), 7.27 ± 1.31 h/d (n = 113) for 2–4 months postpartum, 7.02 ± 1.05 h/d (n = 105) for 5–7 months postpartum, and 7.45 ± 1.05 h/d (n = 115) for 12–17 months postpartum. The incidence of insufficient sleep (<7 h/d) before pregnancy (12.17%) was significantly less than at any follow-up time after delivery (vs. 2–4 months postpartum, χ² = 10.101, p = 0.001; vs. 5–7 months postpartum, χ² = 15.281, p < 0.0001; vs. 12–17 months postpartum, χ² = 6.426, p = 0.011). The percentage of insufficient maternal sleep was highest at 5–7 months postpartum (34.29%). No significant difference was found between the incidence of insufficient sleep at 5–7 months postpartum, 2–4 months postpartum (29.20%, χ² = 0.650, p = 0.420), and 12–17 months postpartum (25.22%, χ² = 2.168, p = 0.141). At 2–4 months postpartum, the frequency of formula feeding per day is related to reduced maternal sleep duration (Standardization coefficient β = −0.265, p = 0.005, Adjusted R² = 0.061). At 2–4 months and 5–7 months postpartum, the relationship between macronutrients in breast milk and the mother's sleep duration was insignificant (all p > 0.05). Other than the positive correlation found between maternal GHRL and sleep duration (r = 0.3661, p = 0.0305), no significant relationship was observed between sleep duration and other indexes (all p > 0.05).

Conclusions

Postpartum mothers generally sleep less, but there is no correlation between insufficient sleep and the macronutrient content of breast milk. Formula feeding may be related to the mother's sleep loss, while breastfeeding (especially direct breastfeeding) may be related to increased maternal sleep duration. The findings suggest that sleep duration is related to maternal serum GHRL. More high-quality studies are needed to clarify the mechanism of these findings and provide a solid theoretical basis and support references for breastfeeding.

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.

Associations between night-time sleep duration and fasting glucose and ratio of triglyceride to high-density lipoprotein cholesterol among adults free of type 2 diabetes or without diagnosed type 2 diabetes: a multicentre, cross-sectional study in China

OBJECTIVES

We aimed to assess the associations between night-time sleep duration and fasting glucose (FG), triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) ratio and body mass index (BMI) among adults free of type 2 diabetes (T2D) or without diagnosed T2D.

DESIGN

Cross-sectional study.

SETTING

Medical examination centres at six hospitals in Beijing-Tianjin-Hebei region, China.

PARTICIPANTS

Participants were recruited via multistage, stratified cluster sampling. We included adults free of T2D or without diagnosed T2D who attended for physical examination and completed the validated questionnaire. 32 497 participants were included in the study, of whom 52.50% were men.

PRIMARY AND SECONDARY OUTCOME MEASURES

FG, TG, HDL-C, height and weight were measured.

RESULTS

Overall, 12.80% and 9.67% reported night sleep duration <7 hours and ≥9 hours, respectively; 6.91% had elevated FG and 3.57% had undiagnosed T2D. Sleep duration had an independent, U-shaped associated with FG (β₁ (linear term)=-0.111, p=0.047; β₂ (quadratic term)=0.008, p=0.026) with 6.9 hours of sleep associated with the lowest FG and a negative association with BMI (β=-0.154, p<0.001). BMI mediated a U-shaped association of sleep duration with TG/HDL-C (β₁=-0.040, p=0.017; β₂=0.003, p=0.023).

CONCLUSIONS

Both short and long night-time sleep was associated with elevated FG, and short sleep duration was associated with increased BMI. BMI mediated a U-shaped association between sleep duration and TG/HDL-C.

Adipokines in Sleep Disturbance and Metabolic Dysfunction: Insights from Network Analysis

Adipokines are a growing group of secreted proteins that play important roles in obesity, sleep disturbance, and metabolic derangements. Due to the complex interplay between adipokines, sleep, and metabolic regulation, an integrated approach is required to better understand the significance of adipokines in these processes. In the present study, we created and analyzed a network of six adipokines and their molecular partners involved in sleep disturbance and metabolic dysregulation. This network represents information flow from regulatory factors, adipokines, and physiologic pathways to disease processes in metabolic dysfunction. Analyses using network metrics revealed that obesity and obstructive sleep apnea were major drivers for the sleep associated metabolic dysregulation. Two adipokines, leptin and adiponectin, were found to have higher degrees than other adipokines, indicating their central roles in the network. These adipokines signal through major metabolic pathways such as insulin signaling, inflammation, food intake, and energy expenditure, and exert their functions in cardiovascular, reproductive, and autoimmune diseases. Leptin, AMP activated protein kinase (AMPK), and fatty acid oxidation were found to have global influence in the network and represent potentially important interventional targets for metabolic and sleep disorders. These findings underscore the great potential of using network based approaches to identify new insights and pharmaceutical targets in metabolic and sleep disorders.

Sleep onset, duration, or regularity: which matters most for child adiposity outcomes?

BACKGROUND/OBJECTIVES

Sleep measures, such as duration and onset timing, are associated with adiposity outcomes among children. Recent research among adults has considered variability in sleep and wake onset times, with the Sleep Regularity Index (SRI) as a comprehensive metric to measure shifts in sleep and wake onset times between days. However, little research has examined regularity and adiposity outcomes among children. This study examined the associations of three sleep measures (i.e., sleep duration, sleep onset time, and SRI) with three measures of adiposity (i.e., body mass index [BMI], waist circumference, and waist-to-height ratio [WHtR]) in a pediatric sample.

SUBJECTS/METHODS

Children (ages 4-13 years) who were part of the U.S. Newborn Epigenetic STudy (NEST) participated. Children (N = 144) wore an ActiGraph for 1 week. Sleep measures were estimated from actigraphy data. Weight, height, and waist circumference were measured by trained researchers. BMI and WHtR was calculated with the objectively measured waist and height values. Multiple linear regression models examined associations between child sleep and adiposity outcomes, controlling for race/ethnicity, child sex, age, mothers' BMI and sleep duration.

RESULTS

When considering sleep onset timing and duration, along with demographic covariates, sleep onset timing was not significantly associated with any of the three adiposity measures, but a longer duration was significantly associated with a lower BMI Z-score (β = -0.29, p < 0.001), waist circumference (β = -0.31, p < 0.001), and WHtR (β = -0.38, p < 0.001). When considering SRI and duration, duration remained significantly associated with the adiposity measures. The SRI and adiposity associations were in the expected direction, but were non-significant, except the SRI and WHtR association (β = -0.16, p = 0.077) was marginally non-significant.

CONCLUSIONS

Sleep duration was consistently associated with adiposity measures in children 4-13 years of age. Pediatric sleep interventions should focus first on elongating nighttime sleep duration, and examine if this improves child adiposity outcomes.

A Tailored Web-Based Video Intervention (ParentCoach) to Support Parents With Children With Sleeping Problems: User-Centered Design Approach

Background

Many parents frequently struggle with undesirable or problematic behavior (ie, temper tantrums and whining) displayed by their child. To support parents in promoting positive parenting skills (ie, recognizing challenging situations and reacting appropriately), the interactive video e-learning tool ParentCoach was developed. The tool aims to teach parents generic behavioral responses by means of situational learning, tailoring, and problem solving. The first demonstration focused on sleeping problems.

Objective

The aim of this paper is to illustrate the user-centered development of ParentCoach.

Methods

We conducted usability, understandability, and acceptance tests among the target group (29 parents, 7 youth health care professionals, and 4 individuals with former lower health literacy) in different phases of the development process via focus groups, interviews, and surveys. This allowed for relevant insights on specifications and user requirements to guide the development and revision of the tool in each iteration.

Results

Iterative testing and development allowed for the final demonstration of ParentCoach to be experienced as a relevant and accessible parenting intervention that can be used as a stand-alone program or in combination with another program.

Conclusions

This paper elaborates on the iterative development process and its benefits for the final demonstration of ParentCoach.

Sleep Disturbance and Metabolic Dysfunction: The Roles of Adipokines

Adipokines are a growing group of peptide or protein hormones that play important roles in whole body metabolism and metabolic diseases. Sleep is an integral component of energy metabolism, and sleep disturbance has been implicated in a wide range of metabolic disorders. Accumulating evidence suggests that adipokines may play a role in mediating the close association between sleep disorders and systemic metabolic derangements. In this review, we briefly summarize a group of selected adipokines and their identified function in metabolism. Moreover, we provide a balanced overview of these adipokines and their roles in sleep physiology and sleep disorders from recent human and animal studies. These studies collectively demonstrate that the functions of adipokine in sleep physiology and disorders could be largely twofold: (1) adipokines have multifaceted roles in sleep physiology and sleep disorders, and (2) sleep disturbance can in turn affect adipokine functions that likely contribute to systemic metabolic derangements.

Sleep Duration/Quality With Health Outcomes: An Umbrella Review of Meta-Analyses of Prospective Studies

Background

To quantitatively evaluate the evidence of duration and quality of sleep as measured by multiple health outcomes.

Methods

This review is registered with PROSPERO, number CRD42021235587. We systematically searched three databases from inception until November 15, 2020. For each meta-analysis, the summary effect size using fixed and random effects models, the 95% confidence interval, and the 95% prediction interval were assessed; heterogeneity, evidence of small-study effects, and excess significance bias were also estimated. According to the above metrics, we evaluated the credibility of each association.

Results

A total of 85 meta-analyses with 36 health outcomes were included in the study. We observed highly suggestive evidence for an association between long sleep and an increased risk of all-cause mortality. Moreover, suggestive evidence supported the associations between long sleep and 5 increased risk of health outcomes (stroke, dyslipidaemia, mortality of coronary heart disease, stroke mortality, and the development or death of stroke); short sleep and increased risk of overweight and/or obesity; poor sleep quality and increased risk of diabetes mellitus and gestational diabetes mellitus.

Conclusions

Only the evidence of the association of long sleep with an increased risk of all-cause mortality was graded as highly suggestive. Additional studies are needed to be conducted.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42021235587

The links between sleep duration, obesity and type 2 diabetes mellitus

Global rates of obesity and type 2 diabetes mellitus (T2DM) are increasing globally concomitant with a rising prevalence of sleep deprivation and sleep disorders. Understanding the links between sleep, obesity and T2DM might offer an opportunity to develop better prevention and treatment strategies for these epidemics. Experimental studies have shown that sleep restriction is associated with changes in energy homeostasis, insulin resistance and β-cell function. Epidemiological cohort studies established short sleep duration as a risk factor for developing obesity and T2DM. In addition, small studies suggested that short sleep duration was associated with less weight loss following lifestyle interventions or bariatric surgery. In this article, we review the epidemiological evidence linking sleep duration to obesity and T2DM and plausible mechanisms. In addition, we review the impact of changes in sleep duration on obesity and T2DM.

Prospective associations between sedentary behavior and physical activity in adolescence and sleep duration in adulthood

The purpose of this prospective study was to investigate whether sedentary screen time (SST) and physical activity in adolescence were related to sleep duration in adulthood and whether these associations varied by sex. We analyzed data from 9279 adolescents who participated in Waves I and V of the National Longitudinal Study of Adolescent Health (Add Health) in the United States. SST was measured by reported hours spent watching television/videos or playing video/computer games per week. Physical activity was measured with participation in school team club sports and frequency (times/week) of moderate to vigorous physical activity (MVPA). Results from multinomial regression models indicated that adolescents with more SST, particularly 15-21 h (Relative Risk Ratio [RRR] = 1.18, 95% CI: 1.02-1.36) or 22 or more hours (RRR = 1.19, 95% CI: 1.06-1.35) compared to 0-7 h per week SST, had significantly higher relative risk of short sleep (six or fewer hours) in adulthood, after controlling for demographic characteristics, socioeconomic status and health behaviors at Waves I and V, sleep duration at Wave I, and SST and MVPA at Wave V. The association between 22 or more hours per week SST in adolescence and later short sleep varied by sex (RRR = 0.75, 95% CI: 0.58-0.95) and was significantly stronger among males. Measures of physical activity in adolescence did not predict sleep duration. Decreasing adolescents' SST to prevent suboptimal sleep later in development may be a target for further investigation, particularly for males.

What Is the Impact of Energy Expenditure on Energy Intake?

Coupling energy intake (EI) to increases in energy expenditure (EE) may be adaptively, compensatorily, or maladaptively leading to weight gain. This narrative review examines if functioning of the homeostatic responses depends on the type of physiological perturbations in EE (e.g., due to exercise, sleep, temperature, or growth), or if it is influenced by protein intake, or the extent, duration, timing, and frequency of EE. As different measures to increase EE could convey discrepant neuronal or humoral signals that help to control food intake, the coupling of EI to EE could be tight or loose, which implies that some ways to increase EE may have advantages for body weight regulation. Exercise, physical activity, heat exposure, and a high protein intake favor weight loss, whereas an increase in EE due to cold exposure or sleep loss likely contributes to an overcompensation of EI, especially in vulnerable thrifty phenotypes, as well as under obesogenic environmental conditions, such as energy dense high fat—high carbohydrate diets. Irrespective of the type of EE, transient elevations in the metabolic rate seem to be general risk factors for weight gain, because a subsequent decrease in energy requirement is not compensated by an adequate adaptation of appetite and EI.

Weekend night vs. school night sleep patterns, weight status, and weight-related behaviors among adolescents

OBJECTIVE

In this study, we examine associations between objectively measured weekend night vs. school night sleep patterns, weight status, and weight-related behaviors among adolescents.

DESIGN

Cross-sectional study.

SETTING

Five Minnesota high schools that started early (7:30 or 7:45 AM) in Spring 2016.

PARTICIPANTS

Ninth grade students, ages 14.5-16 years (n = 284).

MEASUREMENTS

Students completed surveys, had body measurements taken, and wore sleep (wrist) actigraphs for 1 week (n = 284). We examined weekend night-school night differences in sleep duration and sleep timing. We then assessed whether these factors were related to weight status and weight-related behaviors (eating behaviors, food consumption, physical activity, beverage consumption) using generalized linear mixed models.

RESULTS

On average, students slept 1.5 hours (95% confidence interval 1.3-1.7) more and had a sleep midpoint 1.9 hours (1.8-2.1) later on weekend nights compared to school nights. Female students had larger increases in sleep duration on weekend nights than males but similar timing differences. Sleep duration differences were uncorrelated with sleep timing differences (r = 0.01). Neither duration nor timing differences were associated with overweight, obesity, or any of the eating behaviors we examined. However, sleeping longer on weekend nights than on school nights was associated with lower probability of being active 6-7 days per week (p = .02).

CONCLUSIONS

Adolescents have substantial sleep duration and sleep timing differences on weekend nights vs. school nights. While these differences may not be associated with weight status or weight-related behaviors, they reflect the reality that most adolescents have schedules that restrict their sleep.

Sleep habits and weight status in Brazilian children aged 4-6 years of age: the PREDI study

OBJECTIVES

To evaluate the association of sleep habits with the weight status of children aged 4-6 years.

METHODS

Data were obtained from the PREDI Study, a Brazilian birth cohort study. The current study was carried out in the homes of the participants during two follow-ups: 2016/17 and 2018. The participants were submitted to anthropometric assessment and demographic, socioeconomic and sleep data were obtained. The child's sleep habits were self-reported by the mother or caregiver on the day of the visit and included information on the following sleep habits during the past week: bedtime routine, rhythmicity, and separation affect determined with the Sleep Habits Inventory for Preschool Children and the Sleep Habits Inventory. Logistic regression and gamma-log regression analyses were used to examine the association of sleep habits with excess body weight of children in the two follow-ups according to sex.

RESULTS

Of the 217 and 185 children included in 2016/17 and 2018, respectively, 66 (30.6%) and 48 (25.9%) had a BMI >85th percentile at 4-6 years, respectively. The median rhythmicity score was higher in children with excess body weight (p = 0.05). Adjusted analysis showed that rhythmicity was associated with excess body weight of girls at ages 4-5 years (OR = 1.42, 95% CI: 1.09-1.86, p = 0.009) and 6 years (OR = 1.32, 95% CI: 1.06-1.65, p = 0.015), even after adjustment for other important covariates. Additionally, the sleep habit "separation affect" was inversely associated with the child's BMI in boys (β = -0.005, 95% CI: -0.010-0.000, p = 0.037).

CONCLUSIONS

In the present study, rhythmicity problems were associated with increased odds of girls aged 4-6 years having excess body weight. These results are important from a public health perspective since strategies aimed at preventing excess body weight in children need to consider the child's sleep quality as a potential risk factor, especially rhythmicity.

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.

Nighttime sleep duration trajectories were associated with body mass index trajectories in early childhood

BACKGROUND

The respective contribution of total, daytime and nighttime sleep duration in childhood obesity remains unclear.

OBJECTIVES

To assess the longitudinal association between developmental trajectories of sleep duration and BMI z-score in early childhood.

METHODS

Data were from the Melbourne INFANT program, a prospective cohort with 4-month-old infants being followed-up until age 60 months (n = 528). Sleep duration (total, daytime, nighttime) and BMI z-score were measured using questionnaire at ages 4, 9, 18, 43 and 60 months. Group-based trajectory modelling was used to describe longitudinal trajectories from ages 4 to 60 months. Multivariable logistic regression was conducted to assess the association between sleep duration and BMI z-score trajectories.

RESULTS

Three nighttime sleep duration trajectory groups were identified: "Long stable" (10.5 to 11.0 hours, 61%), "catchup long" (8.0 to 11.5 hours, 23%) and "short stable" (8.7 to 9.8 hours, 16%) nighttime sleepers. BMI z-score trajectory groups were classified as "low-BMIz" (-1.5 to -0.5 unit, 21%), "mid-BMIz" (-0.5 to 0.5 unit, 58%) and "high-BMIz" (0.8 to 1.4 unit, 21%). With adjustment for child and maternal covariates, both "catchup long" (OR 3.69 95%CI 1.74, 7.92) and "long stable" nighttime sleepers (OR 4.27 95%CI 2.21, 8.25) revealed higher odds of being in the "mid-BMIz" than the "high-BMIz" group. By contrast, total or daytime sleep duration trajectories were not associated with BMI z-score trajectories.

CONCLUSIONS

Longer nighttime, but not total or daytime, sleep duration was associated with lower BMI z-score trajectories in early childhood. Our findings reinforce the importance of nighttime sleep for healthy body-weight development in early childhood.

Integrated metabolomics and proteomics analysis reveals energy metabolism disorders in the livers of sleep-deprived mice

Sleep deprivation (SD) has been linked to impaired mental and physical health, obesity, and various diseases. However, the molecular mechanism underlying the effects of SD in the liver is still unclear. To investigate the metabolome and proteome alterations in the liver, an in vivo model of SD was established based on automated random motion platform techniques by applying a strategy of 10 consecutive days of 20 h of sleep deprivation +4 h of resting. The liver's altered metabolites and proteins were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and data analyses were performed with MetaboAnalyst 5.0. This study found 15 differential metabolites, including 12 upregulated- metabolites and 3 downregulated- metabolites. A total of 493 proteins were differentially regulated, including 377 upregulated- proteins and 116 downregulated- proteins. The glutathione metabolism, fructose and mannose metabolism, and pyruvate metabolism pathways had significant effects on the sleep-deprived mouse livers. These three active pathways cause energy metabolism disorder and may induce obesity. In conclusion, this study demonstrates that SD could change the metabolism of glucose, and specific fatty acids, amino acids, and critical enzymes in the liver, providing a reference for the health effects of insufficient sleep. SIGNIFICANCE STATEMENT: So far, little is known about the changes in metabolites and proteins in the liver of individuals who suffer from SD. Metabolites and proteins in serum, urine and hypothalamus do not entirely reflect the effects of sleep deprivation on the whole body. In addition, many SD-induced models used the multiplatform water environment method, which causes mice to fall into the water frequently. Under this condition, the physical exertion of mice is extremely high, and it is not suitable for long-term sleep deprivation. The SD induction process has caused some influence on the model. Finally, few studies have elucidated the imbalance of energy metabolism caused by SD to induce obesity from the molecular mechanism. This study used a rotary table deprivation apparatus to trigger SD. This method will not cause excessive consumption and stimulation of mice. Furthermore, this study analyzed the metabolic and proteomic changes in the liver and enriched the range and means of metabolic and proteomic changes in sleep deprived mice. Finally, this research provides reference for elucidating the molecular mechanism of sleep deprivation causing energy metabolism disorders in the liver of mice.

Sleep duration and overweight: is there a relationship in adolescence?

OBJECTIVE

This study aimed to investigate the association between sleep duration and excess weight in Brazilian adolescents.

METHODS

This is a cross-sectional study conducted with 65,837 adolescents, aged 12 to 17 years, enrolled in the Study of Cardiovascular Risks in Adolescents (ERICA). Sleep duration was assessed by means of a questionnaire focusing on weekday and weekend hours of sleep. Nutritional status was assessed based on body mass index, and participants were classified according to age and gender. The statistical analysis was performed with the Stata 13 software, using the survey command. Poisson regression was used to determine the association of excess weight with sleep duration categories.

RESULTS

A decline in sleep duration was associated with advancing age. The prevalence of short and long-term sleep among adolescents was 17.9 and 3.6%, respectively, while overweight was diagnosed in 25.5% of the sample. Adolescents who reported having short sleep had 10% (PR = 1.10; 95%CI 1.06 - 1.15) more overweight, while those who reported sleeping more than 11 hours had approximately 12% (PR = 0.88; 95%CI 0.78 - 0.99) less excess weight.

CONCLUSION

Our findings reinforce the assumption that insufficient sleep poses health risks, and encouraging regular and sufficient sleep may be a cost-effective intervention for the prevention of overweight in adolescence.

Cross-sectional associations between objectively measured sleep characteristics and body mass index in European children and adolescents

BACKGROUND

Short sleep duration has been found to be associated with a higher risk for overweight and obesity. However, previous studies have mainly relied on subjective measures of sleep duration and other sleep characteristics (eg quality, timing) have often been neglected. Therefore, we aimed to investigate associations between several, mainly objectively measured sleep characteristics and body mass index (BMI). Further, we aimed to identify distinct sleep subtypes based on these sleep characteristics and to study their association with BMI.

METHODS

Children aged 9-16 years participating in the European I.Family study (N = 559, 51.2% girls, 32.9% overweight/obese) wore an accelerometer for one week on their wrist and recorded their daily wake-up and lights-off times in a sleep diary. Information on sleep duration, sleep efficiency and sleep latency was derived. To identify sleep subtypes, we conducted a latent class analysis using all five sleep variables. Associations between single sleep variables, sleep subtype and age- and sex-specific BMI z-score were investigated using linear mixed-effects regression models to accommodate clustering among siblings.

RESULTS

No statistically significant associations were observed between the single sleep variables (sleep duration, sleep efficiency, sleep latency, wake-up and lights-off times) and BMI z-score. Four sleep subtypes were identified and children were assigned to one of the groups based on their highest probability for latent group membership: "early birds" (17.5% of the sample), "short sleep duration" (14.7%), "optimal sleep" (47.6%) and "poor sleep quality" (20.2%). Sleep subtype was not associated with BMI z-score.

CONCLUSIONS

Using objective sleep data, we did not find convincing evidence for associations between the sleep variables under investigation and BMI.

Self-administered electroencephalography-based sleep assessment: compliance and perceived feasibility in children and adults

Background

Sleep is a crucial part of our lives and insufficient sleep has been linked to several health disorders in both children and adults. However, most studies are based on single night laboratory polysomnography, actigraphy, or sleep diaries. The primary aim of this study was to evaluate compliance to and perceived feasibility of the Zmachine insight+ for assessment of habitual sleep parameters in a sample of children and adults for six nights. The secondary aim was to report sleep parameters derived from the Zmachine.

Methods

We analyzed data from 12 families who participated in the SCREENS pilot trial (2018–2019). Children (n=14) and adults (n=19) had to undergo three nights of EEG-based sleep assessment at baseline and follow-up. We assessed compliance to the sleep assessment protocol and summarized perceived feasibility in children and adults. Summary estimates were computed for total sleep time, sleep onset latency, wake after sleep onset, light sleep, deep sleep, and rapid eye movement sleep.

Results

Compliance to the sleep assessment protocol was high with 92.9 and 89.4% of children and adults meeting the a priori specified compliance goal of at least two out of three nights of complete sleep data at both baseline and follow-up. In general, the protocol was perceived as feasible, with low prevalence of sleep disruption and only minor issues, e.g. difficulties with removing sensors. Results on sleep parameters indicate large within group variation.

Conclusions

Our findings support the use of a self-administered EEG-based habitual sleep assessment protocol, including multiple days of measurement, in children and adults.

Trial registration

Cilinicaltrials.gov: NCT03788525 [Secondary outcome measures; Retrospectively registered; 27th December, 2018].

Systematic review and meta-analyses of the relationship between short sleep and incidence of obesity and effectiveness of sleep interventions on weight gain in preschool children

The aim of this study is to determine (a) whether short sleep is associated with the incidence of obesity and (b) whether interventions beneficial for sleep reduce weight gain in preschool children. We systematically searched PubMed, Embase, Web of Science and Cochrane up to 12/09/2019. (a) Studies that were included were prospective, had follow-up ≥1 year, with sleep duration at baseline and required outcome measures. (b) Intervention trials with sleep intervention and measures of overweight or obesity were included. Data were extracted according to PRISMA guidelines. (a) The risk of developing overweight/obesity was greater in short sleeping children (13 studies, 42 878 participants, RR: 1.54; 95% CI, 1.33 to 1.77; p < 0.001). Sleep duration was associated with a significant change in BMI z-score (10 studies, 11 cohorts and 29 553 participants) (mean difference: -0.02 unit per hour sleep; -0.03 to -0.01; p < 0.001). (b) Four of the five intervention studies reported improved outcomes: for BMI (-0.27 kg/m² ; -0.50 to -0.03; p = 0.03); for BMI z-score (-0.07 unit; -0.12 to -0.02; p = 0.006). Short sleep duration is a risk factor or marker of the development of obesity in preschool children. Intervention studies suggest that improved sleep may be beneficially associated with a reduced weight gain in these children.

Children's Body Mass Index Depending on Dietary Patterns, the Use of Technological Devices, the Internet and Sleep on BMI in Children

Due to the increase in overweight as well as obesity in children, the researchers undertook the studies to determine the occurrence of these irregularities and identify the factors leading to them. The study aimed to assess the body mass index of the children subcategorized and compared depending on the dietary patterns, the use of technical devices, the Internet, and sleeping habits. The study group consisted of 376 children (189 girls and 187 boys) aged 6 to 15. The body composition estimates were obtained with the use of a foot-to-foot bioelectrical impedance analysis, the body height was measured by means of a stadiometer, and blood pressure was monitored. The research questionnaire was distributed among the surveyed and included the question concerning the children's lifestyle, eating and sleeping habits, the use of electronic devices, the Internet, and socio-demographic data. As indicated, the number of sleeping hours per day significantly negatively correlated with body mass index (BMI), whereas the frequency of using the smartphone had a positive correlation with BMI. The children who sleep less and spend more time using the smartphone had higher BMI values. Bearing in mind the conditions that may have an influence on the BMI of early-school age children, the emphasis must be placed on healthy lifestyle education among children and parents alike.

Factors associated with overweight and abdominal obesity in Brazilian school-aged children: a comprehensive approach

Objective We investigated the association between demographic, socio-economic, perinatal, parental and lifestyle-related factors with general and abdominal obesity among prepubertal children aged 6 to 8 years in a Southeastern city of Brazil. Subjects and methods A total of 486 children were randomly selected from public schools in the city of Patos de Minas, and examined to determine body mass index (BMI) and waist circumference (WC). Demographic, socio-economic, perinatal, parental and lifestyle-related data were obtained and assessed as independent risk factors for overweight/obesity and abdominal obesity, using multiple regression analysis. Results Obesity/overweight (BMI percentile ≥ 85), seen in 19% of the children, was positively associated with low maternal education, being born small for gestational age, maternal BMI and screen time, whereas abdominal obesity (WC percentile > 90), seen in 9.9% of the children, was positively associated with maternal age and maternal BMI. When BMI and WC percentile were analyzed as continuous variables, birth by cesarean section, parental BMI, and lower sleep time were positively associated with BMI percentile, and birth by cesarean section, being born small for gestational age, and parental BMI were positively associated with WC percentile. Conclusion Our findings suggest that the frequency of overweight and obesity in a city in the Southeastern region of Brazil is similar to the global frequency reported by the World Health Organization. We also found that many modifiable risk factors were associated with general and abdominal obesity, and these may possibly substantiate future strategies to prevent childhood obesity and its consequences in adult life.

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.

Social jetlag, eating behaviours and BMI among adolescents in the USA

There is a lack of research on associations of social jetlag with eating behaviours and obesity among adolescents. We examined the associations of social jetlag with eating behaviours and BMI in adolescents before and after adjustment for potential confounders. Self-report data were collected from 3060 adolescents (48·1 % female, mean age 15·59 (sd 0·77) years) from the Fragile Families and Child Wellbeing Study. In regression models, social jetlag predicted odds of consumption of breakfast, fruits/vegetables, fast food and sweetened drinks and BMI percentile. Primary models adjusted for school night sleep duration, sex, age, household income and youth living arrangements; secondary models further adjusted for race/ethnicity. In fully adjusted models, greater social jetlag was associated with lower odds of consumption of breakfast (OR = 0·92, P = 0·003) and fruits/vegetables (OR = 0·92, P = 0·009) and higher odds of consumption of fast food (OR = 1·18, P < 0·001) and sweetened drinks (OR = 1·18, P < 0·001). Social jetlag was positively associated with BMI percentile after additional adjustment for eating behaviours (b = 0·84, P = 0·037), but this relationship was attenuated after adjustment for race/ethnicity (b = 0·72, P = 0·072). Ethnoracial differences in social jetlag may attenuate the association of social jetlag with BMI and should be considered in future studies of circadian misalignment, eating behaviours and obesity markers.

Sleep duration and body mass: direction of the associations from adolescence to young adulthood

Research suggests that sleep duration and obesity are related, but the direction of this association remains uncertain. We applied autoregressive cross-lag models to evaluate the directionality of the relationship between sleep duration and BMI from adolescence through emerging and young adulthood, life stages where the risk for developing obesity are particularly high. Using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), we examined sex-stratified associations between sleep duration and BMI in this cohort from adolescence (ages 12-18, year 1996), to emerging adulthood (ages 18-24, 2001-2002), to young adulthood (ages 24-32, 2008), controlling for key confounders. For both males and females, higher BMI during an earlier developmental stage was associated with shorter sleep duration in the subsequent stage (both Bs = -0.02, ps < 0.01). However, sleep duration at an earlier developmental stage was not associated with BMI at the subsequent stage. Findings suggest that researchers should be cautious when interpreting cross-sectional relationships between sleep and BMI, as higher BMI may precede shorter sleep during adolescence to young adulthood. Researchers may also wish to account for potential bi-directional associations when modeling sleep and BMI using longitudinal data.