Relation between sleep duration, overweight, and metabolic syndrome in Korean adolescents

The Impact of Poor Sleep Quality on Cardiovascular Risk Factors and Quality of Life

This review article examines the impact of poor sleep quality on cardiovascular risk factors and quality of life. Insufficient sleep and disturbances in sleep have been linked to a variety of negative health outcomes, including an increased risk of cardiovascular disease, elevated blood pressure, obesity, and a reduced quality of life. This review explores the available evidence connecting poor sleep with these health conditions, analyzing the underlying mechanisms and pathways involved. Additionally, the challenges posed by night work, which can contribute to poor sleep and subsequent health problems, are discussed. The review also discusses evidence-based strategies for improving sleep quality, encompassing sleep hygiene practices, bright light therapy, cognitive behavioral therapy for insomnia, pharmacological interventions, and emerging digital health solutions. The aim is to analyze current research and emphasize the crucial role of prioritizing sleep quality in maintaining both cardiovascular health and quality of life.

The synergistic impact of sleep duration and obesity on metabolic syndrome risk: exploring the role of microRNAs

Introduction

Given the well-established association between metabolic syndrome (MetS) and obesity, this study elucidates the influences of sleep duration and weight on MetS risk and explores the potential role of miRNAs as underlying mechanisms.

Methods

According to sleep logs and biochemistry tests, this study investigated the association between MetS and its components, sleep duration, and weight in four subgroups: A: normal sleepers with normal weight (N = 145), B: normal sleepers with obesity (N = 140), C: short sleepers with normal weight (N = 130), and D: short sleepers with obesity (N = 142). Chi-square, one-way ANOVA, and Tukey's post hoc tests were used for statistical analysis. Furthermore, following total RNA isolation by TRIzol from blood samples, cDNA was synthesized using stem-loop technique. Quantitative real-time polymerase chain reaction (qRT-PCR) was then employed to evaluate the expression levels of miR-33a, miR-378a, miR-132-3p, and miR-181d. The data were analyzed using one-way ANOVA.

Results

Our findings revealed the strongest association between MetS prevalence and individuals in group D (short sleepers with obesity; Cramer's V = 0.649, P < 0.001). This observation underscores the synergistic effect of short sleep and obesity on MetS risk. Furthermore, there was an independent association between short sleep duration and elevated triglyceride levels (P < 0.05). MicroRNA expression analysis revealed downregulation of miR-33a and miR-181d in B, C, and D groups compared to the normal group. Conversely, miR-132-3p expression was upregulated in the B, C, and D groups.

Conclusion

Short sleep and obesity synergistically elevate MetS risk, potentially via miR-33a and miR-181d downregulation and miR-132-3p upregulation, impacting triglyceride metabolism.

Omega-3 and omega-6 fatty acids food intake and metabolic syndrome in adolescents 12 to 17 years old: A school-based cross-sectional study

BACKGROUND & AIMS

Fatty acids (FAs) of the omega-3 and omega-6 family are considered essential, and adequate intake seems to be associated with lower risk of developing chronic non-communicable diseases. The objective was to evaluate the association of omega-3 and omega-6 FAs dietary intake with the prevalence of MS and its components waist circumference (WC), blood pressure (BP), fasting blood glucose, triglycerides and High Density Lipoprotein - cholesterol (HDL-c) in Brazilian adolescents aged 12-17 years.

METHODS

This is a school-based cross-sectional investigation, using data from the Study of Cardiovascular Risks in Adolescents (ERICA), carried out between 2013 and 2014. The following variables were collected and assessed: 1) sociodemographic (sex, age, type of school, school location whether urban or rural and region of the country); 2) food consumption was measured through a 24-h Food Recall (24 hR), and a second 24 hR was applied to 7% of the total sample; 3) anthropometrics (weight, height, WC), BP and biochemical (glycemia, triglycerides and HDL-c) were also assessed. Logistic regression analysis was performed according to gender and age group.

RESULTS

A total of 36,751 adolescents participated in the study. The intake of omega-3 FAs in the total population was 1.71 g/day and of omega-6 FAs, 13.56 g/day, with an omega-6/omega-3 ratio of 7.93:1. It was found that higher intake of omega-3 FAs was associated with an 53% lower chance of low HDL-c. For omega-6 FAs, no significant results were found.

CONCLUSIONS

The findings indicated an association between omega-3 FAs and HDL-c. More studies are needed to elucidate the effects of omega-6 FAs.

Sleep duration is associated with metabolic syndrome in adolescents and children: a systematic review and meta-analysis

STUDY OBJECTIVES

Studies on the associations between sleep duration and metabolic syndrome in adolescents and children have reported mixed results. To shed more light on this issue, we conducted this meta-analysis by synthesizing the results of previous studies.

METHODS

Studies were retrieved from PubMed, Ovid, Cochrane, and Embase from inception to October 2021. Fixed-effects models and random-effects models were used to analyze the effects of sleep time on metabolic syndrome in adolescents.

RESULTS

Data from 7 studies, including 13,305 adolescents and children, were meta-analyzed. Compared with the control group, short sleep durations were not associated with a high prevalence of metabolic syndrome in adolescents and children using a random-effects model (odds ratio = 0.92, 95% confidence interval = 0.48-1.37, I2 = 56.5%, P = .378). Using a fixed-effects model on long sleep duration, this association was statistically significant (odds ratio = 0.57, 95% confidence interval = 0.38-0.76, I2 = 0.0%, P < .001) as a protective factor compared with shorter sleep duration.

CONCLUSIONS

Long sleep duration, instead of short sleep duration, was significantly associated with a lower prevalence of metabolic syndrome among adolescents and children.

CITATION

Xu Y, Hua J, Wang J, Shen Y. Sleep duration is associated with metabolic syndrome in adolescents and children: a systematic review and meta-analysis. J Clin Sleep Med. 2023;19(10):1835-1843.

Investigation of the relationship between sleep-related parameters and metabolic syndrome (MetS) among youths in the Southeast of Iran

BACKGROUND AND AIM

There are few studies and inconsistent findings on the role of sleep-related parameters in the development of metabolic syndrome (MetS) among youths. In this study, we aim to investigate the relationship between sleep-related parameters and MetS among youths in a large sample size in Rafsanjan, a region in the southeast of Iran.

METHODS

The current cross-sectional study was performed on 3,006 young adults aged 15-35, who registered for Rafsanjan Youth Cohort Study (RYCS), as part of Rafsanjan Cohort Study (RCS)). In fact, RCS is a branch of the prospective epidemiological research studies in Iran (PERSIAN). In the present study, we included 2,867 youths after excluding some subjects with missing information on MetS components. MetS was diagnosed based on Adult Treatment Panel III (ATP III) criteria. Besides, data on sleep-related parameters were collected by self-report questionnaires.

RESULTS

The overall prevalence of MetS was 7.74% among the participants. In addition, bedtime, wake time, napping, night shift work, and sleep duration per night and day had no association with the higher odds of having MetS. In contrast, long sleep duration at night was associated with the lower odds of high waist circumference (WC) (OR: 0.82,95% CI :0.67-0.99).

CONCLUSION

In the present study, long sleep duration at night was associated with lower odds of central obesity. However, more longitudinal studies with the objective measurement of sleep-related parameters are needed to verify the associations reported in the current study.

Sleep Duration and Metabolic Syndrome among Early Adolescents-A Cross-Sectional Study in Khartoum State, Sudan

Numerous studies have reported that sleep disorders are linked to poor health outcomes. However, studies on these associations in children and adolescents in an African context are limited. The aim of the present study was to analyze the relationship between sleep duration and the presence of metabolic syndrome among early adolescents in Sudan. Methods: A cross-sectional study was conducted on participants aged 10-15 years in Khartoum State, Sudan. Metabolic syndrome (MetS) was diagnosed by increased waist circumference and the presence of two or more metabolic abnormalities (triglycerides [TG], high-density lipoproteins [HDL-C], blood pressure [BP], and fasting plasma glucose [FBG]). Short sleep duration was defined based on National Sleep Foundation (NSF) classification. Data were collected by physical examinations, biochemical analyses, and self-developed standardized questionnaires. Data were analyzed with IBM SPSS Statistics Version 24. A generalized additive model (GAM) was used for the smoothing function between sleep duration and MetS. p < 0.05 was considered as significant. Results: The prevalence of MetS and short sleep among early adolescents aged 10-15 years in Sudan was 2.3% and 55.0%, respectively. A higher prevalence of short sleep was found among overweight and obese participants (p < 0.05). The prevalence of MetS among short sleepers was 2.8%. Binary logistic regression analysis showed that male short sleepers had higher odds of having MetS compared to female short sleepers. The relationship between short sleep and low HDL-C in boys and between short sleep and high TG in girls was statistically significant. The highest risk of MetS was observed at less than 6.5 h of sleep per night. Conclusions: Short sleep duration was significantly associated with overweight/obesity in the total population and with low HDL-C in boys and high triglycerides in girls. A nonlinear curve pattern was observed between sleep duration and prevalence of MetS. Longitudinal studies are needed to further determine the causal relationship between sleep habits and MetS and its components.

Scientific evidence of the association between oral intake of OMEGA-3 and OMEGA-6 fatty acids and the metabolic syndrome in adolescents: A systematic review

AIMS

To conduct a systematic review of the literature on the scientific evidence of the oral intake of omega-3 and omega-6 FAs and metabolic syndrome (MS) in adolescents.

DATA SYNTHESIS

The study was registered in PROSPERO (number 42020185370). Studies were carried out with adolescents aged 10-19 years, who presented as intervention/exposure the oral intake of omega-3 and/or omega-6 fatty acids (FAs), in the databases PubMed, Scopus, Web of Science, LILACS, CENTRAL, and PQDT Global e BDTD. The tools used to assess the risk of bias were RoB 2.0, Agency for Healthcare Research and Quality (AHRQ), and Newcastle-Ottawa Scale. Fifteen papers retrieved published from 2010 to 2019 were included (n = 3534); nine were randomized studies and controlled clinical trials, four were cross-sectional studies, one was a retrospective cohort study, and one case-control study. No studies have evaluated the effect or association of omega-3 and/or of omega-6 FAs with actual MS, only with its components. The randomized clinical trials identified the effects of omega-3 FA on the decrease in blood pressure (n = 1 out of six), glycemia (n = 2 out of seven), and triglycerides (n = 5 out of eight), and the increase in HDL-c (n = 2 out of eight) considering the comparison between the group that received omega-3 FA and the control group.

CONCLUSIONS

Scientific evidence is controversial on the association between oral intake of omega-3 FAs and MS in adolescents, due to the heterogeneity between studies and the divergence of results for the same MS component.

Sleep duration and risk of high blood pressure in Thai adolescents: the Thai National Health Examination Survey V, 2014 (NHES-V)

Background

Sleep duration has been proposed to be associated with high blood pressure. However, nationwide studies regarding this association in adolescents remain limited. This study aimed to explore the national prevalence of high blood pressure among Thai adolescents and to determine the association between sleep duration and high blood pressure.

Methods

Data from adolescents aged 10–19 years from the Thai National Health and Examination Survey V were included. We collected demographic data (including age and gender), height, weight, waist circumference, blood pressure, fasting blood chemistries and sleep duration data. Sleep durations were categorized as short, normal or long for each age group based on the United States National Sleep Foundation’s recommendations. High blood pressure was diagnosed using the 2017 guidelines of the American Academy of Pediatrics. Factors associated with high blood pressure were analyzed using multivariate logistic regression.

Results

A total of 3505 adolescents (1785 female) were included. The prevalence of high blood pressure was 9.4% (95% CI 8.5–10.4%). The high blood pressure group had higher BMI z-score, LDL-C, triglyceride and lower HDL-C than the normotensive group. In the multivariate analysis, BMI z-score, LDL-C and HDL-C were independently associated with high blood pressure. However, there was no association between sleep duration and high blood pressure.

Conclusions

High blood pressure risk was increased in adolescents with high BMI z-score. Neither short nor long sleep duration was associated with an increased risk of high blood pressure.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14430-z.

Associations Between Sleep and Metabolic Outcomes in Preadolescent Children

Context

Growing evidence suggests an important role for sleep for the metabolic health of children.

Objective

We aimed to determine how sleep is related to insulin sensitivity, insulin secretion, beta-cell function, and adiposity (BMI z-scores, body fat %, waist to height ratio) using objectively measured sleep and oral glucose tolerance test (OGTT)-derived measures.

Methods

Sixty-two children aged 7-11 years, born at Kaiser Permanente Southern California, wore wrist accelerometers for 7 days to objectively measure sleep, completed an OGTT, and had anthropometric measures (height [cm], weight [kg], waist [cm], body fat [%]) collected. Using linear regression, associations between Matsuda insulin sensitivity index (ISI), insulinogenic index (IGI), disposition index (DI), BMI z-score, waist to height ratio, and body fat % with sleep parameters [total sleep time (TST; min), sleep efficiency (SE; %), time in bed (TIB; min), wake after sleep onset (WASO; min), and sleep latency (SL; min)] were assessed. Body fat % was tested as a mediator of the relationship between TST and ISI.

Results

Longer TST was associated with better insulin sensitivity (P = 0.02), but not after adjusting for body fat %. Sleep parameters were not associated with IGI or DI. Longer TST was associated with lower % body fat (P = 0.01) and lower waist-to-height-ratios (P = 0.05). Body fat % explained 62% (P = 0.01) of the relationship between TST and ISI. Longer TIB was associated with lower adiposity measures (P < 0.05). There were no associations between SE, WASO, or SL and metabolic outcomes.

Conclusion

Objectively measured sleep duration was associated with lower adiposity, and the relationship between sleep duration and ISI appeared partly through adiposity levels in preadolescent children. Longer sleep duration may be important for metabolic health.

Sleep duration and metabolic body size phenotypes among Chinese young workers

The evidence linking sleep duration and metabolic body size phenotypes is limited, especially in young adulthood. In this study, we aimed to examine the association between sleep duration and metabolic body size phenotypes among Chinese young workers and investigate whether discrepancies exist among shift and non-shift workers. A cross-sectional study was performed between 2018 and 2019 in Wuhan, China and 7,376 young adults aged 20-35 years were included. Self-reported sleep duration was coded into four groups: <7, 7-8, 8-9, and ≥9 h per day. Participants were classified into four metabolic body size phenotypes according to their body mass index and metabolic health status: metabolically healthy normal weight, metabolically unhealthy normal weight, metabolically healthy overweight/obesity (MHO), and metabolically unhealthy overweight/obesity (MUO). Multinomial logistic regression models were used to explore the associations between sleep duration and metabolic body phenotypes. Compared with those who slept 7-8 h each night, those with sleep duration <7 h per day had higher odds of MHO (OR 1.27, 95% CI: 1.02-1.56) and MUO (OR 1.22, 95% CI: 1.03-1.43), irrespective of multiple confounders. Stratification analyses by shift work showed that the association between short nighttime sleep and increased odds of MUO was only observed in shift workers (OR 1.26, 95% CI 1.03-1.54). Sleep duration is independently associated with metabolic body size phenotypes among Chinese young adults, while shift work could possibly modulate the association. These results may provide evidence for advocating adequate sleep toward favorable metabolic body size phenotypes in young workers.

Disparity between Subjective Health Perception and Lifestyle Practices among Korean Adolescents: A National Representative Sample

Background

The relationship between subjective health perception (SHP) and lifestyle practices brings into question the future health status of an individual. Recognition of the disparity between one's health consciousness to the real practices encourages change and promotes development of better health programs. The adolescent stage is the best time to identify this disparity wherein lifestyle practices are still being developed. In Korea, adolescents experienced significant shifts in lifestyle due to the fast economic growth and the breakthrough of the digital era. Thus, determining the disparity between SHP and lifestyle practices among Korean adolescents poses a great deal of interest and importance.

Methods

Utilizing the 2019 Korea Youth Risk Behavior Web-based Survey (KYRBS), self-reported data with a national representative sample-57,303 respondents-of Korean adolescents in the 7-12^th grades, was used from a multistage sampling, stratification, and clustering was obtained. SHP and lifestyle practices were collected and analyzed.

Results

The findings revealed that most respondents with poor diet, exercise, and sleep behaviors perceived themselves to be normal, healthy, or extremely healthy, which resulted in a negative correlation between SHP and lifestyle behaviors-except in the case of substance use.

Conclusion

There is a significant disparity between Korean adolescents' SHP and lifestyle practices. This highlights the need for lifestyle interventions and re-education among Korean adolescents. Their current lifestyle practices may extend into adulthood, thereby increasing the risks of cardiovascular and other lifestyle-induced diseases.

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.

Stress of life events and anxiety as mediators of the association between insomnia and triglycerides in college students

Purpose: This study examined interrelationships among insomnia, stress, anxiety, and metabolic risk factors. Methods: A total of 124 college students were included in the analysis (age = 21 ± 1 years). Insomnia, stress of life events, and anxiety were assessed using self-reported questionnaires. Fasting blood samples were assayed for glucose, insulin, total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-cholesterol), and low-density lipoprotein cholesterol (LDL-cholesterol). Results: Insomnia was positively associated with stress of life events (β = 0.28, p < .001) and anxiety (β = 0.46, p < .001). Insomnia was related to elevated fasting insulin (β = 0.12, p = .04) and triglyceride level (β = 1.85, p < .001). An inverse association was found between insomnia and HDL-cholesterol (β = -0.45, p = .03). Sobel's test for mediation showed that stress of life events (p = .020) and anxiety (p = .013) mediated the relationship between insomnia and hypertriglyceridemia. Conclusions: Reducing stress and anxiety among college students with insomnia may influence subsequent cardiovascular health.

Fat-to-lean mass ratio as a new anthropometric indicator in predicting metabolic syndrome among Malay adolescents in Terengganu, Malaysia

Background

Metabolic syndrome (MetS) is defined as a cluster of risk factors for predicting type 2 diabetes mellitus and cardiovascular disease.

Objectives

This cross-sectional study aimed to develop a cut-off value for fat versus lean mass ratio (FLMR) in predicting MetS and to investigate the association between this indicator with MetS and its components.

Methods

Subjects comprised 238 Malay adolescents (79% female) aged 18–19 years old. Anthropometric assessment comprised weight, height and waist circumference (WC). Body composition was measured using bioelectrical impedance analysis techniques while blood pressure was measured using a blood pressure monitor. Fasting blood glucose, total cholesterol , triglycerides, high-density lipoprotein cholesterol (HDL-c), and low-density lipoprotein cholesterol were determined from an overnight fasting blood sample. MetS was determined based on International Diabetes Federation (2007) definition for adolescents aged 16-year-old and above.

Results

The prevalence of MetS was 2.1%. Receiver Operating Characteristics curve analysis revealed that the optimal cut-off value for FLMR was 0.441 with an Area Under the Curve of 0.874 (95% CI: 0.825, 0.913); with sensitivity of 80.0% and specificity of 71.0%. FLMR cut-off of 0.441 was associated with high WC ( p < .001), low HDL-c ( p < .001) and MetS ( p < .05). Binary Logistic Regression analysis revealed that adolescents with high WC, low HDL-c and MetS had higher odds of developing increased FLMR than the cut-off value with an odds ratio (OR) of 43.4 (95% CI: 9.7,193.9), 4.7 (95% CI: 2.3,9.8) and 13.3 (95% CI: 1.5,121.2), respectively.

Conclusion

FLMR possesses fair discriminatory ability in identifying MetS among adolescents and significant association exists between FLMR and MetS and some of its components.

Social Jetlag and Cardiometabolic Risk in Preadolescent Children

Objective: Childhood cardiometabolic disease risk (CMD) has been associated with short sleep duration. Its relationship with other aspects of sleep should also be considered, including social jetlag (SJL) which represents the difference between a person's social rhythms and circadian clock. This study investigated whether childhood CMD risk is associated with sleep duration, sleep disturbances, and SJL.

Study Design: The observational study included 332 children aged 8–10 years (48.5% female). The three independent variables were sleep duration, sleep disturbances, and SJL. SJL was calculated as the variation in hours between the midpoint of sleep during free (weekend) days and work/school days. Eleven cardiometabolic biomarkers were measured, including central blood pressure, lipids, glycated hemoglobin, arterial wave reflection, and glucose. Underlying CMD risk factors were identified using factor analysis.

Results: Four underlying CMD risk factors were identified using factor analysis: blood pressure, cholesterol, vascular health, and carbohydrate metabolism. Neither sleep disturbances nor sleep duration were significantly associated with any of the four CMD factors following adjustments to potential confounders. However, SJL was significantly linked to vascular health (p = 0.027) and cholesterol (p = 0.025).

Conclusion: These findings suggest that SJL may be a significant and measurable public health target for offsetting negative CMD trajectories in children. Further studies are required to determine biological plausibility.

Prevalence of Metabolic Syndrome among Children and Adolescents in High-Income Countries: A Systematic Review and Meta-Analysis of Observational Studies

Introduction. Metabolic syndrome (MetS) is an assemblage of interconnected cardiovascular risk factors that are prevalent among children and adolescents in high-income countries (HICs). Despite the presence of several studies on the issue, the study findings are incongruent due to the absence of a gold standard diagnostic method of MetS in children. Thus, the findings of the original studies are inconclusive for policy makers and other stakeholders. This systematic review and meta-analysis is aimed at giving conclusive evidence about MetS among children and adolescents in HICs. Methods. We conducted searches using electronic databases (PubMed, Scopus, Web of Science, CINAHL (EBSCOhost), EMBASE (Elsevier), and Medline (EBSCOhost)) and other sources (Google Scholar and Google) up to September 2020. Observational studies reporting the prevalence of MetS were eligible in this study. The pooled estimates were computed in fixed and random effect models using six diagnostic methods (IDF, ATP III, de Ferranti et al., WHO, Weiss et al., and Cruz and Goran). Publication bias was verified using funnel plots and Egger’s regression tests. Subgroup and sensitivity analysis were performed in case of higher heterogeneities among the included studies. Result. In this study, 77 studies with a total population of 125,445 children and adolescents were used in the final analysis. Metabolic syndrome among the overweight and obese population was computed from 28 studies with the pooled prevalence of 25.25%, 24.47%, 39.41%, 29.52%, and 33.36% in IDF, ATP III, de Ferranti et al., WHO, and Weiss et al. criteria, respectively. Likewise, 49 studies were eligible to compute the pooled prevalence of MetS in the general population of children and adolescents. Hence, MetS was found in 3.70% (IDF), 5.40% (ATP III), 14.78% (de Ferranti et al.), 3.90% (WHO), and, 4.66% (Cruz and Goran) of study participants. Regarding the components of MetS, abdominal obesity in the overweight and obese population, and low HDL-C in the general population were the most common components. Besides, the prevalence of Mets among males was higher than females. Conclusion. This study demonstrates that MetS among children and adolescents is undoubtedly high in HICs. The prevalence of MetS is higher among males than females. Community-based social and behavioral change communications need to be designed to promote healthy eating behaviors and physical activities. Prospective cohort studies could also help to explore all possible risk factors of MetS and to design specific interventions accordingly.

Longitudinal association between sleep and 5-year incident metabolic syndrome in older Chinese adults: a community-based cohort study

PURPOSE

Our aim was to investigate the association between sleep and the development of metabolic syndrome (MetS) in Chinese older adults and to accumulate evidence for the prevention of MetS through sleep management.

METHODS

This prospective study followed 3005 participants aged over 60 derived from the Weitang Geriatric Diseases Study who were without MetS at baseline. MetS was defined according to the Adult Treatment Panel III (ATP III) criteria. Logistic regression models were fit to assess the association between sleep and MetS incident and a linear regression model was used to examine the impact of sleep duration on every component of MetS. Data on sleep-related parameters were obtained based on a self-reported questionnaire.

RESULTS

After five-year follow-up, 13.51% participants developed MetS, of which 46.86% were women. The incidence of MetS was highest among adults who slept 6 h or less and lowest among those who slept 7 h after adjusted for multiple variables. Subgroup analyses showed no gender specificity. The variation of fasting plasma glucose (FBG) for ≥9 h per night was significantly lower than that for 7.01-7.99 h per night (β = -0.18, P < 0.05). Sleeping for 8-8.99 h also decreased the variation of diastolic blood pressure (DBP) compared to 7.01-7.99 h (β = -0.84, P < 0.05).

CONCLUSION

We conclude that both short and long sleep duration are risk factors for MetS incident in older adults.

The Relationship between Sleep, Obesity, and Metabolic Health in Adolescents - a Review

In this literature review, we discuss the importance of adequate sleep and the various effects of suboptimal sleep on weight maintenance and metabolic health specifically for adolescents. Two major contributors to adolescents experiencing decreased sleep duration and quality, and thus increasing the risk for developing metabolic syndrome in adolescence as well as later in adulthood, are increased electronic screen time particularly at night and early school start times. The less time adolescents spend sleeping, the less quality sleep they obtain, and the greater the disruption of endocrine hormone function. As another consequence, adolescents are more prone to making poor food choices, from choosing relatively nutrient-poor foods to consuming excess calories without necessarily increasing their energy expenditure. These choices put adolescents at greater risk for becoming obese throughout their lifespan.

Association between short sleep duration and metabolic syndrome in Chinese children and adolescents

BACKGROUND

The relationship between short sleep duration and metabolic syndrome (MetS) in children and adolescents has been inconsistent. This study aimed to examine the association between short sleep duration and MetS in Chinese children and adolescents.

METHODS

Data were from a cross-sectional survey conducted in Jinan, China between September 2013 and November 2014. A total of 1008 children and adolescents aged 6-17 years were included. Sleep duration was self-reported by participants and categorized as normal or short (<9 h in children aged 6-12 years or <8 h in adolescents aged 13-17 years) according to the recommendations of the American Academy of Sleep Medicine. MetS was defined based on the modified criteria of the National Cholesterol Education Program Adult Treatment Panel III.

RESULTS

After adjusted for sex, age, parental education levels, and midpoint of sleep, compared with normal sleep duration, short sleep duration was associated with increased odds of MetS (odds ratio [OR]: 1.79, 95% confidence interval [CI]: 1.09-2.95) and abdominal obesity (OR: 1.60, 95% CI: 1.14-2.25). In the subgroups stratified by age and sex, compared with normal sleep duration, short sleep duration was associated with increased odds of abdominal obesity (OR: 2.34, 95% CI: 1.07-5.13) in girls aged 6-12 years; short sleep duration was associated with increased odds of MetS (OR: 2.49, 95% CI: 1.06-5.84), abdominal obesity (OR: 2.30, 95% CI: 1.10-4.82), and high TG (OR: 2.63, 95% CI: 1.11-6.21) in boys aged 13-17 years.

CONCLUSIONS

Short sleep duration associated with higher odds for MetS in Chinese children and adolescents. Interventions to improve sleep duration could help prevent and control MetS among children and adolescents.

Poor Sleep Quality Decreases Concurrent Training Benefits in Markers of Metabolic Syndrome and Quality of Life of Morbidly Obese Patients

Background: Sleep quality (SQ) plays a role in multiple activities of daily living, but little is known about its role in concurrent training [CT, high-intensity interval (HIIT) plus resistance training (RT)] adaptations for metabolic syndrome (MetS) and health-related quality of life (HRQoL) markers. The aim of the present study was to determine the effects of a 20-week CT programme on MetS and HRQoL markers according to the SQ of morbidly obese patients. Methods: Twenty-nine morbidly obese patients were allocated to one of two groups: good sleep quality (GSQ, n = 15, 38.07 ± 12.26 years) and poor sleep quality (PSQ, n = 14, 40.79 ± 11.62 years). HRQoL, body mass index, waist circumference (WC), systolic and diastolic blood pressure (SBP and DBP, respectively), and plasma outcomes were measured. Results: The GSQ group reported significant changes (pre- vs. post-intervention) in WC (114.0 ± 3.1 vs. 110.4 ± 3.4 cm, p = 0.012), SBP (137.0 ± 4.3 vs. 125.6 ± 1.8 mmHg, p = 0.006), and HRQoL general health (51.33 ± 21.08 vs. 64.33 ± 16.24, p = 0.020). By contrast, the PSQ group showed significant changes only in SQ (9.00 ± 2.42 vs. 5.36 ± 2.84, p = 0.004). Conclusions: Morbidly obese PSQ patients showed a lower response for improving MetS and HRQoL markers after a 20-week CT programme than GSQ peers. However, there was a greater effect size for decreasing WC and SBP in favour of the GSQ compared with the PSQ group, suggesting that there are limitations to CT benefits on these outcomes in the PSQ group. These results call for more complex future studies.

EVIDENCE OF THE ASSOCIATION BETWEEN SLEEP DURATION AND BLOOD PRESSURE IN ADOLESCENTS: A SYSTEMATIC REVIEW

OBJECTIVE

To review the epidemiological evidence of the association between sleep duration and blood pressure in adolescents.

DATA SOURCES

We performed a systematic review of observational studies in Medline, Scopus, Lilacs, Web of Science, Science Direct databases and Virtual Libraries in English, Spanish and Portuguese published until September 2018. Studies were selected first by title and abstract, then by complete reading, according to the eligibility criteria. The reference list of selected articles was evaluated in order to retrieve relevant studies.

DATA SYNTHESIS

Initially, 1,455 articles were retrieved. After exclusion due to duplicity or not meeting the eligibility criteria, 13 articles were included in the review. Studies varied greatly in sample size (143 to 6,940 patients), methods of measuring blood pressure and sleep duration, cutoff points, categorization and adjustment of variables. The main evidence from the studies is that short sleep duration is associated with high blood pressure in adolescence, although the presence of association between high blood pressure and long sleep duration is possible, but not clear in the literature.

CONCLUSIONS

Sleep duration, especially short duration, is associated with high blood pressure in adolescents. Such evidence draws attention to implications on cardiovascular health in this age group.

Demographic and Socioeconomic Influences on Sleep Patterns among Adolescent Students

Although proper sleep is an important topic in adolescent health, little is known about the sleep patterns of adolescents from a longitudinal and non-Western perspective. To fill this gap, the present research conducted a longitudinal study of the impact of demographic and socioeconomic factors on sleep patterns among Korean adolescent students. The relationship could positively or negatively affect sleep. Therefore, it is important to understand which demographic and socioeconomic factors are related to sleep patterns. This study used nationally representative panel data from the Korean Children and Youth Panel Survey. A series of descriptive analyses were conducted to provide overall characteristics of the sample. Furthermore, mixed effect regression analysis techniques were employed to test the relationship between demographic and socioeconomic factors and sleep patterns. Paternal employment status was associated with adolescent sleep patterns, while maternal employment status was not. Adolescents with both parents working compared to adolescents with one parent or none working showed different sleep patterns on weekdays but not on weekends. Both parents possessing college degrees, household income, living in an urban area, and family type were associated with adolescent sleep pattern indicators to varying degrees. Some of these associations varied according to adolescent sex. This study provides insight into the impact of demographic and socioeconomic factors on weekend and weekday sleep patterns among adolescent students by sex. These findings provide information for the promotion of healthy sleep in adolescents by addressing demographic and socioeconomic factors.

The interrelation of sleep and mental and physical health is anchored in grey-matter neuroanatomy and under genetic control

Humans need about seven to nine hours of sleep per night. Sleep habits are heritable, associated with brain function and structure, and intrinsically related to well-being, mental, and physical health. However, the biological basis of the interplay of sleep and health is incompletely understood. Here we show, by combining neuroimaging and behavioral genetic approaches in two independent large-scale datasets (HCP (n = 1106), age range: 22-37, eNKI (n = 783), age range: 12-85), that sleep, mental, and physical health have a shared neurobiological basis in grey matter anatomy; and that these relationships are driven by shared genetic factors. Though local associations between sleep and cortical thickness were inconsistent across samples, we identified two robust latent components, highlighting the multivariate interdigitation of sleep, intelligence, BMI, depression, and macroscale cortical structure. Our observations provide a system-level perspective on the interrelation of sleep, mental, and physical conditions, anchored in grey-matter neuroanatomy.

Tune out and turn in: the influence of television viewing and sleep on lipid profiles in children

BACKGROUND/OBJECTIVES

Physical activity is beneficial to lipid profiles; however, the association between sedentary behavior and sleep and pediatric dyslipidemia remains unclear. We aimed to investigate whether sedentary behavior or sleep predicted lipid profiles in children over a 2-year period.

SUBJECTS/METHODS

Six hundered and thirty children from the QUALITY cohort, with at least one obese parent, were assessed prospectively at ages 8-10 and 10-12 years. Measures of sedentary behavior included self-reported TV viewing and computer/video game use. Seven-day accelerometry was used to derive sedentary behavior and sleep duration. Adiposity was assessed using DEXA scans. Twenty-four-hour dietary recalls yielded estimates of carbohydrate and fat intake. Outcomes included fasting total cholesterol, triglycerides, HDL and LDL-cholesterol. Multivariable models were adjusted for adiposity and diet.

RESULTS

At both Visit 1 (median age 9.6 year) and Visit 2 (median age 11.6 year), children were of normal weight (55%), overweight (22%), or obese (22%). Every additional hour of TV viewing at Visit 1 was associated with a 7.0% triglyceride increase (95% CI: 3.5, 10.6; P < 0.01) and 2.6% HDL decrease (95% CI: -4.2, -0.9; P < 0.01) at Visit 2; findings remained significant after adjusting for adiposity and diet. Every additional hour of sleep at Visit 1 predicted a 4.8% LDL decrease (95% CI: -9.0, -0.5; P = 0.03) at Visit 2, after adjusting for fat intake; this association became nonsignificant once controlling for adiposity.

CONCLUSIONS

Longer screen time during childhood appears to deteriorate lipid profiles in early adolescence, even after accounting for other major lifestyle habits. There is preliminary evidence of a deleterious effect of shorter sleep duration, which should be considered in further studies.

Bedtimes and Blood Pressure: A Prospective Cohort Study of Mexican Adolescents

INTRODUCTION

Hypertension affects up to 5% of children worldwide and predicts later cardiovascular morbidity. Associations of short sleep and hypertension have been frequently reported in adults but less consistently in children. This study aims to examine the role of late bedtimes, a marker of short sleep duration, and potentially misaligned circadian rhythms, on incident elevated blood pressure (BP) in a large cohort of Mexican children.

METHODS

Participants included 2,033 adolescents recruited from public schools in Morelos, Mexico, free from elevated BP (<90th sex, age, and height-standardized percentile). Fourteen months later, all adolescents had a second BP assessment. We abstracted baseline habitual bedtimes from questionnaires to evaluate the association between bedtime and elevated BP incidence (≥90th percentile). Risk ratios and 95% confidence intervals were estimated with discrete-time mixed survival models, adjusting for potential confounders and accounting for clustering by school.

RESULTS

Participants were 12.5 (SD = 0.6) years old at baseline. At the follow-up visit 10% of adolescents had developed elevated BP. Compared to participants with a habitual weekday bedtime between 9 and 10 pm, those with a weekday bedtime 11 pm or later had a 1.87 times higher risk of developing elevated BP over the follow-up period (95% CI = 1.09, 2.21), after accounting for confounders. Participants with earlier weekday bedtimes also had a higher risk of elevated BP (RR = 1.96; 95% CI = 1.27, 3.01). The associations persisted after accounting for wake time.

CONCLUSION

These data showed a U-shaped association between weekday bedtime and elevated/high BP risk among Mexican adolescents.

Multi-ancestry sleep-by-SNP interaction analysis in 126,926 individuals reveals lipid loci stratified by sleep duration

Both short and long sleep are associated with an adverse lipid profile, likely through different biological pathways. To elucidate the biology of sleep-associated adverse lipid profile, we conduct multi-ancestry genome-wide sleep-SNP interaction analyses on three lipid traits (HDL-c, LDL-c and triglycerides). In the total study sample (discovery + replication) of 126,926 individuals from 5 different ancestry groups, when considering either long or short total sleep time interactions in joint analyses, we identify 49 previously unreported lipid loci, and 10 additional previously unreported lipid loci in a restricted sample of European-ancestry cohorts. In addition, we identify new gene-sleep interactions for known lipid loci such as LPL and PCSK9. The previously unreported lipid loci have a modest explained variance in lipid levels: most notable, gene-short-sleep interactions explain 4.25% of the variance in triglyceride level. Collectively, these findings contribute to our understanding of the biological mechanisms involved in sleep-associated adverse lipid profiles.

Dietary Patterns, Exercise, and the Metabolic Syndrome Among Young People in Urban Pakistan (Lahore)

Background: Increasing urbanization, mechanization, and rural-to-urban migration has led to deranged sleeping patterns, surplus energy intake, and sedentary lifestyles in South Asian young people. This shift poses an insidious health risk for the development of metabolic syndrome (MetS). Early detection is needed because in the South Asian population, this syndrome carries an increased risk of comorbidities compared to people without the syndrome. This study was designed to elucidate the prevalence of MetS and its risk factors in young people in urban areas of Pakistan. Methods: A cross-sectional study was conducted in four undergraduate institutions in Lahore, Pakistan. Five hundred and nine young people participated, and each provided their informed consent for the collection of data on their demographic, physical, and biochemical characteristics along with information on their dietary, sleep, and physical activity habits. Results: Most participants reported consuming greater-than-recommended amounts of protein and smaller-than-recommended amounts of vegetables and fruits. The International Diabetes Federation criteria for MetS were fulfilled by 6.1% of the students. Hypertension (67.7%) and hypo-HDL-emia (64.5%) were the most common risk factors. More than 50% of the respondents slept fewer hours per day than recommended, and 33% had a sedentary lifestyle. Men, participants with a family history of metabolic illness and those with low physical activity levels had higher odds of a positive result on screening for MetS. Conclusions: The early detection of MetS and early identification of probable risk factors may make beneficial contributions to both public health and clinical interventions directed at high-risk individuals. Establishing and using cutoff values for modified waist circumference and specific body mass index in Asian populations may aid in early detection.

Association of Bedtime with both Suicidal Ideation and Suicide Planning among Korean Adolescents

STUDY OBJECTIVES

In comparison to other countries, the South Korean population has a short average sleep duration, and studies have suggested that insufficient sleep is a risk factor for suicidal behavior. This study aimed to examine the association of bedtime with suicidal ideation and with suicide planning, respectively, among Korean adolescents.

METHODS

This study included 48,218 participants from the 2017 Korea Youth Risk Behavior Web-based Survey. Participants were divided into three categories: pre-23:00 bedtime, 23:00-01:30 bedtime, and post-01:30 bedtime. Suicidal ideation and suicide planning were the main dependent variables, and multiple logistic regression analysis was performed to examine the target association.

RESULTS

For both male and female respondents, compared to those who had a pre-23:00 bedtime, those whose bedtime was after 01:30 were more likely to have suicidal ideation (post-01:30 bedtime for men: OR = 1.29, 95% CI = 1.16-1.45; for women: OR = 1.32, 95% CI = 1.20-1.44). For suicide planning, the results were also significant for both genders (post-01:30 bedtime for men: OR = 1.41, 95% CI = 1.16-1.70; for women: OR = 1.21, 95% CI = 1.03-1.43). Odds of suicidal ideation were higher for those who had a post-01:30 bedtime on weekdays but not weekends.

CONCLUSIONS

We found that, among adolescents, going to bed after 01:30 is significantly associated with suicidal ideation and suicide planning, after adjusting for demographic, socioeconomic, and health-related characteristics. Therefore, late bedtime should be the timepoint of a suicide intervention for adolescents, in order to prevent developing suicidal ideations and suicide planning.

Associations between Sleep Pattern and Quality and Cardiovascular Risk Factors among Macao School Students

Background: Despite accumulating evidence showing that sleep duration and cardiometabolic health are correlated, the association of sleep regularity and quality with cardiovascular risk factors in children and adolescents remains inconclusive. Therefore, we examined the relationship between sleep regularity/quality and cardiovascular risk factors in children and adolescents in Macao, China. Methods: We conducted a cross-sectional study among primary and secondary school students (age range: 9-18 years) in Macao, China. Body weight, height, waist circumference (WC), and serum lipid levels were measured. Sleep regularity and sleep quality were assessed by using the Pittsburgh Sleep Quality Index. Multivariable logistic regression was conducted to examine the relationship of sleep variables with the increased likelihood of body mass index (BMI)-classified overweight/obesity, WC-classified obesity, and dyslipidemia. Results: A total of 1078 school students were included in the analysis. Differences of >2 hours between weekday and weekend bedtimes were associated with the increased risk of BMI-classified overweight/obesity (odds ratio = 2.58, 95% confidence interval = 1.55-4.31, p < 0.01) after being adjusted for sleep variables and lifestyle factors. No statistically significant association was found between poor sleep quality and any other outcome. Conclusions: Irregular bedtime was associated with elevated body weight regardless of sleep amount and quality. Thus, regular bedtimes are recommended as a simple but practical strategy for preventing obesity.

Association of Sleep Duration with Obesity and Cardiometabolic Risk Factors in Children and Adolescents: A Population-Based Study

This study aimed to evaluate the relationships between sleep duration and overweight/obesity, obesity, and metabolic syndrome (MetS) and its components in children and adolescents. A total of 6,048 participants aged 10–18 years were divided into the following four sleep-duration groups based on age-specific sleep duration: i) very short; ii) short; iii) recommended; and iv) long. The participants in the very short sleep-duration group had an increased odds ratio (OR) of 1.76 for overweight/obesity, 1.69 for obesity, and 1.49 for elevated waist circumference (WC) compared with the recommended sleep-duration group. The subjects in the long sleep-duration group had an increased OR of 2.71 for elevated triglyceride (TG) compared with those in the recommended sleep-duration group. In subgroup analyses, boys in the very short sleep-duration group exhibited an increased OR of 1.78 for overweight/obesity compared with those in the recommended sleep-duration group. Compared with girls in the recommended sleep-duration group, those in the very short sleep-duration group exhibited an increased OR of 1.69 for overweight/obesity, 2.28 for obesity, and 1.57 for elevated WC; in contrast, girls in the very short sleep-duration group exhibited a decreased OR of 0.58 for elevated TG. The girls in the long sleep-duration group had an increased OR of 3.86 for elevated TG compared with those with recommended sleep-duration. Our results suggest that shorter sleep durations may be related to overweight/obesity, obesity, and central obesity, and longer sleep durations may be associated with elevated TG. However, the nature of these relationships may be dependent on sex.

Levels and correlates of 24-hour movement behaviors among South Koreans: Results from the Korea National Health and Nutrition Examination Surveys, 2014 and 2015

PURPOSE

This study aimed to examine the levels and correlates of 24-h movement behaviors (i.e., physical activity, sedentary time, and sleep), and different patterns of these behaviors in a nationally representative sample of South Koreans aged 12 years and older. This study also aimed to examine the sociodemographic correlates of 24-h movement behaviors stratified by age groups.

METHODS

Self-reported, repeated cross-sectional data from 10,708 participants in the 2014 and 2015 Korea National Health and Nutrition Examination surveys were used. Key variables included moderate-to-vigorous intensity physical activity, muscular strengthening exercises, walking, active transportation, sedentary time, and sleep. Sociodemographic variables included age, sex, household income, area of residence, and education level. Descriptive statistics by sex and age as well as general linear models by age group were performed.

RESULTS

The proportions of individuals meeting the moderate-to-vigorous intensity physical activity, muscular strengthening exercises, and sleep guidelines were, respectively, 21.6%, 22.1%, and 32.5% in male youth; 6.9%, 4.5%, and 22.8% in female youth; 55.5%, 30.8%, and 54.0% in male adults; 48.8%, 14.4%, and 57.6% in female adults; 44.0%, 30.6%, and 45.5% in male older adults; and 29.5%, 8.9%, and 37.3% in female older adults. The proportions of individuals showing the most ideal combinations of 24-h movement behaviors were only 3.2% in youth, 0.4% in adults, and 0 in older adults. Universally, older age, female sex, or living in metro Seoul were associated with unfavorable patterns of 24-h movement behaviors across different age groups. However, the associations of income and education with movement behaviors were mixed across age groups.

CONCLUSION

Overall, the proportion of South Koreans with a healthy 24-h movement behavior pattern is low. The sociodemographic correlates of different types of 24-h movement behaviors should be considered when designing targeted interventions for the promotion of healthy active living for South Koreans.

Association between sleep duration and high blood pressure in adolescents: a systematic review and meta-analysis

CONTEXT

Sleep has been assessed as a risk factor for health consequences. Among adults, excessively longer and shorter sleep durations are associated with high blood pressure (BP), but knowledge of the association between sleep duration and high BP among adolescents is limited.

OBJECTIVES

To estimate the associations between sleep duration and high BP in adolescents.

METHODS

PubMed, Web of Science, and Cochrane databases were searched for eligible publications up until 20 November 2017. This study reviewed the reference lists from retrieved articles to search for relevant studies. Pooled odds ratios (ORs) were calculated using a random-effects meta-analysis. Sub-group and sensitivity analyses were conducted to identify heterogeneity. Publication bias was evaluated using Egger's test.

RESULTS

Seven studies involving 21,150 participants were included, with ages ranging from 10-18 years. For primary analysis, compared with the reference sleep duration, the pooled OR for high BP was 1.51 (95% confidence interval [CI] = 1.04-2.19) for the short sleep duration overall. For long sleep duration, the pooled OR was 1.04 (95% CI = 0.78-1.38). Further sub-group analysis showed that short sleep duration had a higher risk of incident high BP in males (OR = 1.55, 95% CI = 1.24-1.93) than in females (OR = 1.23, 95% CI = 0.47-3.22).

CONCLUSIONS

Among adolescents, and particularly male adolescents, short sleep duration may be a risk factor for high BP. More attention should be given to this lifestyle factor.

Association of sleep duration with metabolic syndrome and its components in children and adolescents; a propensity score-matched analysis: the CASPIAN-V study

OBJECTIVE

This study aims to evaluate the association of sleep duration with metabolic syndrome (MetS) and its components in a pediatric population.

METHODS

This multi-centric cross-sectional study was conducted in 2015 in 30 provinces of Iran. Participants consisted of 4200 school students aged 7-18 years, studied in a national school-based surveillance program (CASPIAN-V). Physical examinations and laboratory tests were performed using standard protocols. The analysis was conducted based on the propensity score matching and conditional logistic regression was used to evaluate the association of short sleep (less than 8 h a day) and the onset of sleep with MetS and its components. Results of conditional logistic regression was reported as odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Overall, 3843 of participants completed the survey (response rate: 91.5%). Their mean (SD) age was 12.3 (3.2) years and 50.6% were boys. In the multivariate model, individuals who slept less than 8 h a day had significantly higher odds of MetS (OR 2.05, 95% CI 1.19-3.63) and high blood pressure (BP) (OR 1.46, 95% CI 1.04-2.06). Association between short sleep duration with other MetS components (including abdominal obesity, hypertriglyceridemia, hyperglycemia, and low levels of high-density lipoprotein-cholesterol was not statistically significant (P > 0.05). Moreover, association between the onset of sleep with MetS and its components was not statistically significant (P > 0.05).

CONCLUSION

Short sleep duration is associated with increased risk of MetS and high BP in children and adolescents. The clinical impact of current findings should be assessed in future longitudinal studies.

Associations of sleep duration and quality with serum and hepatic lipids: The Netherlands Epidemiology of Obesity Study

Short and long sleep duration and poor sleep quality may affect serum and hepatic lipid content, but available evidence is inconsistent. Therefore, we aimed to investigate the associations of sleep duration and quality with serum and hepatic lipid content in a large population‐based cohort of middle‐aged individuals. The present cross‐sectional study was embedded in the Netherlands Epidemiology of Obesity (NEO) study and consisted of 4260 participants (mean age, 55 years; proportion men, 46%) not using lipid‐lowering agents. Self‐reported sleep duration and quality were assessed using the Pittsburgh Sleep Quality Index questionnaire (PSQI). Outcomes of this study were fasting lipid profile (total cholesterol, low‐density lipoprotein [LDL]‐cholesterol, high‐density lipoprotein [HDL]‐cholesterol and triglycerides), postprandial triglyceride (response) levels, and hepatic triglyceride content (HTGC) as measured with magnetic resonance spectroscopy. We performed multivariable linear regression analyses, adjusted for confounders and additionally for measures that link to adiposity (e.g. body mass index [BMI] and sleep apnea). We observed that relative to the group with median sleep duration (≈7.0 hr of sleep), the group with shortest sleep (≈5.0 hr of sleep) had 1.5‐fold higher HTGC (95% confidence interval [CI]: 1.0‐2.2). The group with PSQI score ≥ 10 had a 1.1‐fold (95% CI: 1.0‐1.2) higher serum triglyceride level compared with the group with PSQI ≤ 5. However, these associations disappeared after adjustment for BMI and sleep apnea. Therefore, we concluded that previously observed associations of shorter sleep duration and poorer sleep quality with an adverse lipid profile, may be explained by BMI and sleep apnea, rather than by a direct effect of sleep on the lipid profile.

Objective Sleep Characteristics and Cardiometabolic Health in Young Adolescents

: media-1vid110.1542/5778442247001PEDS-VA_2017-4085Video Abstract BACKGROUND AND OBJECTIVES: Shorter sleep duration is associated with childhood obesity. Few studies measure sleep quantity and quality objectively or examine cardiometabolic biomarkers other than obesity.

METHODS

This cross-sectional study of 829 adolescents derived sleep duration, efficiency and moderate-to-vigorous physical activity from >5 days of wrist actigraphy recording for >10 hours/day. The main outcome was a metabolic risk score (mean of 5 sex-specific z-scores for waist circumference, systolic blood pressure, high-density lipoprotein cholesterol scaled inversely, and log-transformed triglycerides and homeostatic model assessment of insulin resistance), for which higher scores indicate greater metabolic risk. Secondary outcomes included score components and dual-energy radiograph absorptiometry fat mass. We measured socioeconomic status, race and/or ethnicity, pubertal status, and obesity-related behaviors (television-viewing and fast food and sugar-sweetened beverage consumption) using questionnaires.

RESULTS

The sample was 51.5% girls; mean (SD) age 13.2 (0.9) years, median (interquartile range) sleep duration was 441.1 (54.8) minutes per day and sleep efficiency was 84.0% (6.3). Longer sleep duration was associated with lower metabolic risk scores (-0.11 points; 95% CI: -0.19 to -0.02, per interquartile range). Associations with sleep efficiency were similar and persisted after adjustment for BMI z score and physical activity, television-viewing, and diet quality. Longer sleep duration and greater sleep efficiency were also favorably associated with waist circumference, systolic blood pressure, high-density lipoprotein cholesterol, and fat mass.

CONCLUSIONS

Longer sleep duration and higher sleep efficiency were associated with a more favorable cardiometabolic profile in early adolescence, independent of other obesity-related behaviors. These results support the need to assess the role of sleep quantity and quality interventions as strategies for improving cardiovascular risk profiles of adolescents.

Association of sleep disturbances with obesity, insulin resistance and the metabolic syndrome

Insufficient sleep, which has become endemic in recent years, has been variably associated with increased risk of obesity, disorders of glucose and insulin homeostasis, and the metabolic syndrome; to a lesser degree, so has excessive sleep. This review summarizes recent epidemiological and pathophysiological evidence linking sleep disturbances (primarily abnormalities of sleep duration) with obesity, insulin resistance, type 2 diabetes and the metabolic syndrome in children and adults.

Cross-sectional study of randomly selected 18-year-old students showed that body mass index was only associated with sleep duration in girls

AIM

This study investigated the associations, by sex, between sleep and adiposity, dietary habits, cardiorespiratory fitness and metabolic risk in 18-year-old students.

METHODS

We carried out a cross-sectional study of 199 randomly chosen, healthy 18-year-old students (53% girls) in Iceland's capital region. The data collection took place in the winter months of 2012 to 2015. The anthropometric measurements were body mass index, waist circumference and body fat percentage. Sleep duration and dietary habits were self-reported. Cardiorespiratory fitness was measured on a stationary bicycle. A subsample of 152 participants gave blood samples.

RESULTS

A quarter of the adolescents failed to reach the minimum recommended sleep duration of seven hours per night on weekdays. In girls, the average sleep score was associated with body mass index and waist circumference, after adjusting for cardiorespiratory fitness and unhealthy eating scores. In boys, the average sleep score was not associated with anthropometric measurements, but cardiorespiratory fitness was an independent predictor (p < 0.001). No associations were found between average sleep scores and metabolic profiles in either sex.

CONCLUSION

Sleep duration and adiposity only appeared to be associated in girls and were independent of cardiorespiratory fitness and unhealthy eating. Sleep duration was not related to metabolic risk.

Daily sitting time associated with the risk of metabolic syndrome in Korean adolescents

BACKGROUND

This study aimed to investigate the relationship between daily sitting time and the risk of metabolic syndrome in Korean adolescents.

METHODS

Data from 486 adolescents aged 12-18 years were obtained from national surveys. Daily sitting time was measured using questionnaires and divided into three intervals: <8 h; 8-12 h; and ≥12 h.

RESULTS

The mean daily sitting time and prevalence of positive metabolic components were 620.9±9.9 min/day and 45.5±2.7%, respectively. In a multivariate logistic regression analysis, adolescents who sat longer were more likely to have metabolic components (p<0.05), independent of age, sex, area of residence, sleeping time and body mass index.

CONCLUSIONS

Longer daily sitting time appears to be associated with an increased risk of metabolic syndrome in adolescents. These findings highlight the need to focus on reducing sitting time for all adolescents, not just for those at risk of obesity.

Role of sleep duration and sleep-related problems in the metabolic syndrome among children and adolescents

BACKGROUND

There is increasing recognition that sleep is a risk factor for metabolic syndrome (MetS). The aim of the present study was to analyze the relationship between self-reported sleep duration, sleep-related problems and the presence of MetS in children and adolescents from Bogotá, D.C., Colombia.

METHODS

This is a cross-sectional analysis from the FUPRECOL study (2014-15). Participants included 2779 (54.2% girls) youth from Bogota (Colombia). MetS was defined as the presence of ≥3 of the metabolic abnormalities (hyperglycemia, hypertriglyceridemia, low high-density lipoprotein cholesterol [HDL-c], hypertension, and increased waist circumference) according to the criteria of de Ferranti/Magge and colleges. Self-reported sleep duration and sleep-related problems were assessed with the BEARS questionnaire.

RESULTS

Logistic regression analysis showed that boys who meet recommended duration of sleep had a decreased risk of elevated blood glucose levels (Odds Ratio [OR] = 0.71, 95%CI [0.40-0.94]; p = 0.031) compared to boys who have short-long sleep duration. Also, compared to young without sleep problems, excessive sleepiness during the day was related to low HDL-c levels in boys (OR = 1.36, 95%CI [1.02-1.83]; p = 0.036) and high triglyceride levels in girls (OR = 1.28, 95%CI [1.01-1.63]; p = 0.045). Girls with irregular sleep patterns had decreased HDL-c levels (OR = 0.71, 95%CI [0.55-0.91]; p = 0.009).

CONCLUSIONS

Recommended sleep duration was associated with a decreased risk of elevated fasting glucose levels in boys, and sleep problems was related to lower HDL-c in girls and higher triglyceride levels in boys. These findings suggested the clinical importance of improving sleep hygiene to reduce metabolic risk factors in children and adolescents.

Impact of dietary intake, lifestyle and biochemical factors on metabolic health in obese adolescents

BACKGROUND AND AIMS

Obesity devoid of metabolic abnormalities is known as metabolically healthy obesity (MHO). The aim of the study was to examine determinants of MHO during adolescence.

METHODS AND RESULTS

From among 710 obese adolescents, 43 girls and 57 boys were classified as metabolically unhealthy (abdominal obesity and ≥2 risk components of metabolic syndrome). MHO (absence of any cardiometabolic risk factor) was found in 211 girls and 131 boys (regardless of waist circumference) and in 33 girls and 27 boys (without abdominal obesity). Laboratory and anthropometric parameters, dietary records and various lifestyle factors were compared between MHO vs. those unhealthy. The prevalence of MHO regardless of waist circumference was higher in girls than in boys (53.1 vs. 41.9%) but comparable when abdominal obesity was excluded (8.3 vs. 8.6%). Anthropometric variables, levels of gamma-glutamyl transferase, total and low-density lipoprotein cholesterol in both genders, hs-C-reactive protein in girls and alanine aminotransferase in boys differentiated the two metabolic phenotypes. Uric acid was related to metabolic health only in the analysis of MHO without abdominal obesity. Total hours of sleep, bedtime, time of the last daily meal, regular meal consumption and protein intake in boys and screen time, the score of disinhibition and diet composition in girls were found to impact cardiometabolic health.

CONCLUSIONS

In obese adolescents, metabolic health was related to anthropometric and biochemical parameters and only weak associations were found with most of the lifestyle factors studied. Uric acid concentration associated with metabolic health when abdominal obesity was excluded.

Effect of socio-economic status on sleep

AIM

Sufficient sleep is an important factor in physical and mental health. Sleep duration can be affected by socio-economic status (SES). This study aimed to examine the association between sleep duration and SES in Korean adolescents.

METHODS

This study was conducted with 1608 adolescents aged 12-18 years, based on data from the 2010 to 2012 Korean National Health and Nutrition Examination Survey (KNHANES). Sleep duration was self-reported in hours and three SES indicators were used: household income, basic livelihood security programmes and type of health insurance. Confounding factors in this study were age, mental health and physical activity.

RESULTS

Participants' average age was 15.6 ± 0.05 years and average sleep duration was 7.04 ± 0.05 h. There was a strong association between sleep duration and household income (P < 0.05) rather than other socio-economic indicators. In addition, it showed that sleep duration was significantly associated with age, body mass index (P < 0.05) and low mood is associated with short sleep and long sleep (>9 h/night). We found similar results in both genders, that is, that the highest income group had shorter sleep duration than the lowest income group.

CONCLUSIONS

This study shows that the SES, particularly household income, is an important factor in short sleep duration in Korean adolescents. Our findings suggest that, in future investigations of the adolescent's sleep problem, attention should be paid to household income.

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

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

Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies

AIM

Childhood obesity is a major public problem worldwide, and sleep duration may be associated with childhood obesity. We conducted a systematic review and meta-analysis of prospective cohort studies to estimate the associations between sleep duration and obesity/body mass index (BMI) in children.

METHODS

PubMed, Embase and the Cochrane Library were searched. For the meta-analysis, the pooled relative risk (RR) and 95% confidence intervals (CI) were estimated to reveal the association between short sleep duration and obesity. For the review, the outcomes focused on BMI change or subsequent BMI status.

RESULTS

A total of 12 studies (15 populations) met the criteria for inclusion in the meta-analysis. Short sleep duration was significantly associated with obesity (RR: 1.45; 95% CI: 1.14-1.85). After excluding two cohorts that substantially affected the heterogeneity, the pooled results remained significant (RR: 1.30; 95% CI: 1.20-1.42), and the association was not substantially altered in the subgroup analysis. In addition, we summarised 24 studies that met the criteria for our review of the relationship between sleeping and BMI.

CONCLUSION

The present meta-analysis indicated that short sleep duration increased the risk of childhood obesity. Public health efforts that encourage children to have sufficient sleep time may be important in combating obesity.