Sleep duration and obesity in adulthood: An updated systematic review and meta-analysis

Sleep and Oxidative Stress: Current Perspectives on the Role of NRF2

Sleep is a fundamental conserved physiological state across evolution, suggesting vital biological functions that are yet to be fully clarified. However, our understanding of the neural and molecular basis of sleep regulation has increased rapidly in recent years. Among various processes implicated in controlling sleep homeostasis, a bidirectional relationship between sleep and oxidative stress has recently emerged. One proposed function of sleep may be the mitigation of oxidative stress in both brain and peripheral tissues, contributing to the clearance of reactive species that accumulate during wakefulness. Conversely, reactive species, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), at physiological levels, may act as signaling agents to regulate redox-sensitive transcriptional factors, enzymes, and other effectors involved in the regulation of sleep. As a primary sensor of intracellular oxidation, the transcription factor NRF2 is emerging as an indispensable component to maintain cellular redox homeostasis during sleep. Indeed, a number of studies have revealed an association between NRF2 dysfunction and the most common sleep conditions, including sleep loss, obstructive sleep apnea, and circadian sleep disturbances. This review examines the evidence of the intricate link between oxidative stress and NRF2 function in the context of sleep, and highlights the potential of NRF2 modulators to alleviate sleep disturbances.

Role of Adverse Childhood Experiences in the Onset of Overweight/Obesity

PURPOSE OF REVIEW

The goal of this chapter was to summarize the literature on childhood adversity and obesity, discuss treatment implications with a case example, and provide recommendations for trauma-informed care for clinicians who work with individuals living with obesity.

RECENT FINDINGS

Adversity in childhood is related directly and indirectly to obesity development. Upstream contributors like adverse childhood experiences (ACEs) and other factors can lead to experiences of toxic stress and increased allostatic load, resulting in downstream effects of obesity and other chronic health conditions. A well-established literature has linked ACEs and obesity suggesting complex interactions between genetic, biological, behavioral, mental health, social, and environmental factors and obesity. Trauma-informed care strategies can be used to optimize care for individuals living with obesity. Care pathways should include individual (clinician) and systemic (organizational) evidence-based interventions.

Predictors of adherence to a brief sleep extension protocol in emerging adults

OBJECTIVES

This study examined how mental health symptoms (i.e., depression, anxiety, stress) and baseline sleep characteristics (i.e., sleep quality and levels of daytime sleepiness) predicted adherence to and initial success of a brief sleep extension research protocol in emerging adults.

METHODS

184 emerging adults (ages 18-25; M = 20.96, SD = 2.04) were asked to extend their nightly sleep opportunity to 8 hr for 1 week and to anchor bedtime and waketime. Sleep outcomes (adherence and initial protocol success) were tracked using actigraphy. Baseline sleep quality, daytime sleepiness, depression, anxiety, and stress were assessed using self-report questionnaires.

RESULTS

Poorer baseline sleep quality predicted better adherence to the protocol (p = .002). Other baseline sleep characteristics and mental health were not predictive of adherence (ps>.50). Lower levels of baseline daytime sleepiness approached significance in predicting greater initial protocol success following the protocol (p = .05). Baseline sleep quality and mental health did not predict initial protocol success (ps > 0.34).

CONCLUSIONS

Mental health symptoms did not significantly predict adherence to or the success of a sleep extension protocol. Surprisingly, individuals with poor baseline sleep quality were more likely to adhere to the extension protocol, perhaps suggesting heightened motivation for change or increased risk for sleep problems. This research provides valuable insight into factors that predict adherence to sleep extension protocols in emerging adults.

Short sleep duration is associated with higher risk of central obesity in adults: A systematic review and meta-analysis of prospective cohort studies

Background and Objective

The relationship between sleep duration and obesity has been the focus of numerous investigations. This systematic review and meta-analysis of prospective cohort studies aimed to assess the relationship between sleep duration, abdominal obesity, and body composition.

Methods

PubMed, Scopus, and Web of Science were searched until February 2024. Cohort studies that assessed the relationship between sleep duration at night and central obesity measures or body composition indices in adults were included. The quality of studies was assessed using the Newcastle-Ottawa scale. Random-effects meta-analysis was conducted on studies that reported risk ratio (RR) and 95% confidence intervals (CIs).

Results

Eighteen studies were eligible to be included. Eleven out of the 18 studies were not included in the analysis as 10 studies did not report RR, and in one study, the definition of short and normal sleep duration was different from others. The results of the meta-analysis indicated that short sleep duration was significantly associated with abdominal obesity (RR = 1.08; 95% CI: 1.04-1.12; I 2 = 49.1%, n = 7), but long sleep duration was not (RR = 1.02; 95% CI: 0.83-1.24; I 2 = 98.2%, n = 6).

Conclusions

Short sleep duration was associated with a slightly higher risk of central obesity, while long sleep duration was not.

Indices of Sleep Health Are Associated With Timing and Duration of Eating in Young Adults

BACKGROUND

Limited data exist examining whether timing and/or duration of eating behaviors throughout the day affect sleep health.

OBJECTIVE

The aim of this study was to identify the relationship between eating behaviors and sleep in young adults without chronic diseases or conditions.

DESIGN

This was a cross-sectional study using 7 days of baseline data from a randomized crossover trial.

PARTICIPANTS/SETTING

Participants included 52 young adults. The study took place in West Lafayette, Indiana, between April 2017 and May 2018.

MAIN OUTCOME MEASURES

Timing and duration of eating were assessed via 3 nonconsecutive, 24-hour dietary recalls. Bedtime, wake time, total sleep time, sleep latency, sleep efficiency, and wake after sleep onset were measured over 7 days via wrist actigraphy and sleep diaries.

STATISTICAL ANALYSES PERFORMED

Two-way analyses of variance were applied to assess group differences based on timing of consumption (early vs late eating) and duration of eating (long: >13 hours, short: <11 hours, or standard: 11-13 hours) with post-hoc pairwise comparisons.

RESULTS

Main effects of timing of consumption, but not duration of eating, were detected for wake time, bedtime, and sleep efficiency (all, P < .05). Specifically, participants with later eating patterns that included breakfast skipping had later wake times and later bedtimes than those with earlier eating patterns. In addition, those who had later eating patterns that included breakfast skipping and nighttime eating experienced lower sleep efficiency (mean [SE], 77.0% [2.3%]) vs those who consumed breakfast and no nighttime eating (mean [SE], 84.6% [1.4%]; P < .001) and those who skipped breakfast but had no nighttime eating (mean [SE], 84.2% [2.5]; P < .05). Those who consumed breakfast but also had nighttime eating had a mean (SE) sleep efficiency of 82.4% (1.4%) (P = .09).

CONCLUSIONS

The timing of eating was associated with sleep-wake onset and sleep efficiency. This study provides the preliminary characterization of eating behaviors relative to sleep-wake cycles and highlights the need for experimental studies to understand whether manipulating the timing of eating occasions to better align with sleep-wake cycles could improve sleep health.

Associations of actigraphy-assessed sleep variables with adiposity and serum cardiometabolic outcomes in emerging adults

This study assessed associations of actigraphy-assessed sleep with adiposity and serum cardiometabolic outcomes in emerging adults, and whether sex and race modified these associations. Data on 147 emerging adults (age = 19.4 ± 1.3 years; body mass index = 26.4 ± 7.0 kg m-2 ; 59% female; 65% White) from RIGHT Track Health were used. Actigraphy-based sleep measures included sleep duration, sleep efficiency, sleep timing midpoint, day-to-day sleep duration and sleep timing midpoint variability. Combined sleep duration and sleep timing behaviours were also derived (early-bed/late-rise, early-bed/early-rise, late-bed/late-rise, late-bed/early-rise). Outcomes included body mass index and BodPod-assessed fat mass index, fasting serum leptin, C-reactive protein, and homeostatic model assessment-insulin resistance. Sleep duration was 5.4 h per night. We noted an inverse association between sleep duration and homeostatic model assessment-insulin resistance. The early-bed/early-rise group had greater body mass index, C-reactive protein and homeostatic model assessment-insulin resistance compared with the early-bed/late-rise group (referent). Sex modified associations of sleep efficiency with C-reactive protein; stratified results revealed positive association between sleep efficiency and C-reactive protein in males, but not females. Race modified associations of sleep duration with body mass index and leptin, and of sleep duration variability with C-reactive protein. Stratified analyses revealed inverse associations between sleep duration with body mass index and leptin in Black, multiracial/other race individuals only. Positive association between sleep duration variability and C-reactive protein was noted in White individuals only. Shorter sleep duration, particularly when combined with earlier sleep timing, is associated with greater adiposity and serum cardiometabolic outcomes. Additional studies are needed to assess individual- and contextual-level factors that may contribute to sex and race differences in sleep health and cardiometabolic risk in emerging adults.

Sedentary behavior, physical activity, sleep duration and obesity risk: Mendelian randomization study

BACKGROUND

Observational studies have suggested associations between sedentary behaviors (SB), physical activity (PA), sleep duration (SD), and obesity, but the causal relationships remain unclear.

METHODS

We used Mendelian randomization (MR) with genetic variation as instrumental variables (IVs) to assess the causality between SB/PA/SD and obesity. Genetic variants associated with SB/PA/SD were obtained from Genome-wide association study (GWAS), and obesity data came from FinnGen. The primary MR analysis used the instrumental variable weighted (IVW) method, with sensitivity tests including Cochran Q, MR-Egger intercepts, and MR-Radial. Expression Quantitative Trait Loci (eQTL) analysis was applied to identify significant genetic associations and biological pathways in obesity-related tissues.

RESULTS

The MR analysis revealed causal relationships between four SB-related lifestyle patterns and obesity. Specifically, increased genetic liability to television watching (IVW MR Odds ratio [OR] = 1.55, [95% CI]:[1.27, 1.90], p = 1.67×10-5), computer use ([OR] = 1.52, [95% CI]:[1.08, 2.13], p = 1.61×10-2), leisure screen time (LST) ([OR] = 1.62, [95% CI] = [1.43, 1.84], p = 6.49×10-14, and driving (MR [OR] = 2.79, [95% CI]:[1.25, 6.21], p = 1.23×10-2) was found to increase the risk of obesity. Our findings indicate that no causal relationships were observed between SB at work, sedentary commuting, PA, SD, and obesity. The eQTL analysis revealed strong associations between specific genes (RPS26, TTC12, CCDC92, NICN1) and SNPs (rs10876864, rs2734849, rs4765541, rs7615206) in both subcutaneous and visceral adipose tissues, which are associated with these SBs. Enrichment analysis further revealed that these genes are involved in crucial biological pathways, including cortisol synthesis, thyroid hormone synthesis, and insulin secretion.

CONCLUSIONS

Our findings support a causal relationship between four specific SBs (LST, television watching, computer use, driving) and obesity. These results provide valuable insights into potential interventions to address obesity effectively, supported by genetic associations in the eQTL and enrichment analysis. Further research and public health initiatives focusing on reducing specific SBs may be warranted.

Manganese and Sleep Outcomes in United States Adults: Results from the 2017-2020 National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

Manganese (Mn) is an essential micronutrient, but inadequate or excess Mn intake can have a detrimental impact on human health. Despite the essentiality, little is known about the relationship between Mn and sleep.

OBJECTIVE

This study aimed to examine the relationship between blood Mn concentrations and sleep outcomes in US adults.

METHODS

This cross-sectional study used data on blood Mn and sleep from the 2017-2020 National Health and Nutrition Examination Survey (NHANES) (n = 8356, age ≥18 y). Multivariable logistic regression was used to examine associations between quintiles of blood Mn concentrations and subjective sleep outcomes (short sleep duration, late sleep midpoint, trouble sleeping, and obstructive sleep apnea [OSA] symptoms), adjusting for age, gender, body mass index, race/ethnicity, income, smoking, inflammation-adjusted serum ferritin concentration (iron status), caffeine, and alcohol intake. Gender-stratified models were used due to interactions with gender.

RESULTS

The mean (SE) blood Mn concentration was 9.7 (0.1) μg/L in US adults. In males, a nonlinear association was noted in the relationship between blood Mn levels and short sleep duration on weekdays and weekends. The third Mn quintile (Q3) group had lower odds of short sleep duration (<7 h) on weekdays (odds ratio [OR]=0.6, 95% confidence interval [CI]: 0.4, 0.9) than the lowest Mn quintile (Q1, reference) after adjusting for covariates in males. The second Mn quintile (Q2) group had lower odds of late sleep midpoint on weekdays than Q1 (OR=0.6, 95% CI: 0.4, 0.8). In females, Q2 group had lower odds of OSA symptoms than Q1 (OR: 0.6, 95% CI: 0.4, 0.9). No relationship was noted between Mn and trouble sleeping.

CONCLUSIONS

Gender differences exist in the association between Mn and sleep in adults. Q1 group had the poorest sleep outcomes, including higher odds of short sleep duration (in males), late sleep midpoint (in males), and OSA symptoms (in females).

Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016

STUDY OBJECTIVES

We aimed to identify the relationship between duration of categorized catch-up sleep on free days (CUS) and measured body mass index (BMI) in adults using the data from the seventh Korean National Health and Nutrition Examination Survey (KNHANES VII), 2016.

METHODS

CUS duration was classified as ≤ 0, > 0-1, > 1-2, and > 2 hours. Being overweight or obese was defined as having a BMI ≥ 25.0 kg/m2 or ≥ 30.0 kg/m2, respectively.

RESULTS

Of 6,382 participants aged 19-80 years in the KNHANES VII survey of 2016, 201 and 583 participants were excluded because of shift-working and insufficient data, respectively. Of 5,598 participants, CUS was observed in 2,274 (44.9%) participants, of which 3,324 (55.1%), 1,043 (19.4%), 724 (14.7%), and 507 (10.8%) had CUS of ≤ 0, > 0-1, > 1-2, and > 2 hours, respectively; the prevalence of obesity was 5.6%, 5.6%, 4.8%, and 6.1%, respectively. The association between BMI and CUS duration showed a significant negative association in the CUS ≤ 0 hours group (beta [95% confidence interval], -0.394 [-0.646, -0.143], P = .002); however, other CUS groups did not show any significant association with BMI (CUS > 0-1 hours: -0.196 [-1.258, 0.865], P = .716; CUS > 1-2 hours, -0.542 [-1.625, 0.541], P = .325; CUS > 2 hours, -0.113 [-0.459, 0.233], P = .519).

CONCLUSIONS

Our findings provide an understanding of the relationship between CUS and BMI and can serve as an instructive basis for the management of BMI.

CITATION

Lee HJ, Cho S, Lee SH, Kim SJ, Kim KM, Chu MK. Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016. J Clin Sleep Med. 2024;20(1):39-47.

An Update on Sleep Duration, Obesity, and Mortality Risk in Women

Sleep health is an essential component to overall health. Because of numerous societal, economic, and biological factors, obtaining adequate sleep poses a unique challenge to aging women. Yet, women have been traditionally understudied in sleep research. An increasing body of research supports abnormal sleep duration as a risk factor for obesity, cardiovascular disease, and mortality. This review focuses specifically on 3 areas of the discussion of insufficient sleep in women: (1) the mysterious poor health of long sleepers, (2) the potential underlying mechanisms linking abnormal sleep duration and cardiometabolic health, and (3) the need to investigate multiple levels of social determinants driving sleep disparities.

Evaluation of weekend catch-up sleep and weekday sleep duration in relation to metabolic syndrome in Korean adults

PURPOSE

This study aimed to evaluate whether or not the relationship between weekday sleep duration and prevalence of metabolic syndrome (MetS) differs according to weekend catch-up sleep (CUS) in Korean adults.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2016-2020, including that regarding weekday sleep duration, weekend CUS, MetS components, and confounding factors such as sociodemographic factors, health behaviors, and illness-related factors, were evaluated in Korean adults aged 19 to 80 years. Complex-sample logistic regression was applied after adjusting for confounding factors.

RESULTS

Among 24,313 adults, the prevalence of MetS was lowest in individuals with 6-7 h of sleep on weekdays and CUS ≥ 2 h (17.7%, reference group). The interaction between weekday sleep duration and weekend CUS for MetS was significant. Compared to the reference group, the prevalence of MetS was higher in those who slept < 7 h and had a maximum CUS of 1 h (aORs, 1.42-1.66), and in those who slept ≥ 9 h and had a maximum CUS of 2 h (aORs, 1.28-1.82). In subjects with no CUS or CUS ≥ 2 h, the prevalence of MetS was greater even in those with adequate weekday sleep duration (7- 9 h) than in the reference group (aORs, 1.37 and 1.64, respectively).

CONCLUSION

Weekend CUS may help individuals with short weekday sleep duration reduce their odds of developing MetS, but it may worsen the condition in individuals with a long weekday sleep length.

Exploring the relationship between social jetlag with gut microbial composition, diet and cardiometabolic health, in the ZOE PREDICT 1 cohort

PURPOSE

In this study, we explore the relationship between social jetlag (SJL), a parameter of circadian misalignment, and gut microbial composition, diet and cardiometabolic health in the ZOE PREDICT 1 cohort (NCT03479866).

METHODS

We assessed demographic, diet, cardiometabolic, stool metagenomics and postprandial metabolic measures (n = 1002). We used self-reported habitual sleep (n = 934) to calculate SJL (difference in mid-sleep time point of ≥ 1.5 h on week versus weekend days). We tested group differences (SJL vs no-SJL) in cardiometabolic markers and diet (ANCOVA) adjusting for sex, age, BMI, ethnicity, and socio-economic status. We performed comparisons of gut microbial composition using machine learning and association analyses on the species level genome bins present in at least 20% of the samples.

RESULTS

The SJL group (16%, n = 145) had a greater proportion of males (39% vs 25%), shorter sleepers (average sleep < 7 h; 5% vs 3%), and were younger (38.4 ± 11.3y vs 46.8 ± 11.7y) compared to the no-SJL group. SJL was associated with a higher relative abundance of 9 gut bacteria and lower abundance of 8 gut bacteria (q < 0.2 and absolute Cohen's effect size > 0.2), in part mediated by diet. SJL was associated with unfavourable diet quality (less healthful Plant-based Diet Index), higher intakes of potatoes and sugar-sweetened beverages, and lower intakes of fruits, and nuts, and slightly higher markers of inflammation (GlycA and IL-6) compared with no-SJL (P < 0.05 adjusted for covariates); rendered non-significant after multiple testing adjustments.

CONCLUSIONS

Novel associations between SJL and a more disadvantageous gut microbiome in a cohort of predominantly adequate sleepers highlight the potential implications of SJL for health.

Sleep deprivation in development of obesity, effects on appetite regulation, energy metabolism, and dietary choices

Sleep deprivation, which is a decrease in duration and quality of sleep, is a common problem in today's life. Epidemiological and interventional investigations have suggested a link between sleep deprivation and overweight/obesity. Sleep deprivation affects homeostatic and non-homoeostatic regulation of appetite, with the food reward system playing a dominant role. Factors such as sex and weight status affect this regulation; men and individuals with excess weight seem to be more sensitive to reward-driven and hedonistic regulation of food intake. Sleep deprivation may also affect weight through affecting physical activity and energy expenditure. In addition, sleep deprivation influences food selection and eating behaviours, which are mainly managed by the food reward system. Sleep-deprived individuals mostly crave for palatable energy-dense foods and have low desire for fruit and vegetables. Consumption of meals may not change but energy intake from snacks increases. The individuals have more desire for snacks with high sugar and saturated fat content. The relationship between sleep and the diet is mutual, implying that diet and eating behaviours also affect sleep duration and quality. Consuming healthy diets containing fruit and vegetables and food sources of protein and unsaturated fats and low quantities of saturated fat and sugar may be used as a diet strategy to improve sleep. Since the effects of sleep deficiency differ between animals and humans, only evidence from human subject studies has been included, controversies are discussed and the need for future investigations is highlighted.

Modifications of 24-h movement behaviors to prevent obesity in retirement: a natural experiment using compositional data analysis

BACKGROUND

Retirement often leads to a more passive lifestyle and may therefore lead to weight gain. This study aims to investigate longitudinal associations between changes in 24-h movement behaviors and BMI and waist circumference in relation to the transition from work to retirement.

METHODS

The study population included 213 retiring public sector workers (mean age 63.5 years, standard deviation 1.1) from the Finnish Retirement and Aging study. Before and after retirement participants wore an Axivity accelerometer on their thigh and filled in a daily log for at least four days to measure daily time spent sleeping, in sedentary behavior (SED), light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). Also, their body mass index (BMI) and waist circumference were measured repeatedly. Compositional linear regression analysis and isotemporal substitution analysis were used to study associations between one-year changes in 24-h movement behaviors and concurrent changes in BMI and waist circumference.

RESULTS

An increase in MVPA in relation to sleep, SED and LPA was associated with a decreasing BMI (β = -0.60, p = 0.04) and waist circumference (β = -2.14, p = 0.05) over one year from before retirement to after retirement. In contrast, increasing sleep in relation to SED, LPA and MVPA was associated with an increasing BMI (β = 1.34, p = 0.02). Reallocating 60 min from MVPA to SED or sleep was estimated to increase BMI by on average 0.8-0.9 kg/m2 and waist circumference by 3.0 cm during one year.

CONCLUSIONS

During the transition from work to retirement, increasing MVPA was associated with a slight decrease in BMI and waist circumference, whereas increasing sleep was associated with an increasing BMI. Common life transitions, like retirement, should be considered when giving recommendations and guidance for physical activity and sleep.

The Impact of Longitudinal Patterns of Adolescent Sleep Duration on Adult C-Reactive Protein (CRP), Waist-To-Height Ratio, and Body Mass Index (BMI) Among Black and White Individuals

PURPOSE

To assess the impact of longitudinal adolescent sleep duration on adult C-reactive protein (CRP), waist-to-height ratio (WtHR), and body mass index (BMI) by race.

METHODS

Participants (N = 2,399; Mage = 15.7; 40.2% male; 79.2% White, 20.8% Black; Grades 7-12 at Wave I) from the Add Health database provided self-reported sleep duration in Waves I-IV. During Wave V, CRP, WtHR, and BMI were objectively measured. Trajectory analysis was performed using a group-based modeling approach. Chi-square test determined racial differences between groups. General linear models determined relationships between trajectory group, race, and group/race interaction with Wave V CRP, WtHR, and BMI.

RESULTS

Three sleep trajectories emerged: Group 1 "shortest" (24.4%), Group 2 "stable recommended" (67.6%), and Group 3 "varied" (8%). Black individuals and older individuals were more likely to be in Group 1 compared with Group 2. Regardless of race, individuals with patterns of sleep duration increasing to above what is recommended across waves (Group 3) had elevated CRP. Individuals with stable patterns of adequate sleep (Group 2) had lower WtHR. Black individuals with consistently stable patterns of adequate sleep duration had lower BMI compared to those with low sleep duration.

DISCUSSION

Black individuals were more likely to obtain chronically short sleep during the transition from adolescence to adulthood, highlighting a significant health disparity. Poor longitudinal sleep predicted elevated CRP and WtHR. Sleep only impacted BMI for Black individuals. This may relate to racial differences in BMI measurement.

Longitudinal associations between self-reported sleep duration and cardiometabolic disease risk in corporate executives

OBJECTIVE

This study aimed to determine the longitudinal associations between self-reported sleep duration and cardiometabolic disease (CMD) risk in corporate executives.

METHODS

Self-reported sleep duration and lifestyle, occupational, psychological, and anthropometrical, blood pressure and blood marker variables were obtained from 1512 employees at annual health risk assessments in South Africa between 2016 and 2019. Gender-stratified linear mixed models, adjusting for age, lifestyle, occupational and psychological covariates were used to explore these longitudinal associations.

RESULTS

Among women, shorter sleep duration was associated with higher body mass index (BMI) covarying for age only (ß with 95% confidence intervals: -0.19 [-0.36, -0.03]), age and occupational factors (-0.20 [-0.36, -0.03]) and age and psychological factors (-0.20 [-0.37, -0.03]). Among men, shorter sleep was associated with both BMI and waist circumference (WC) covarying for age only (BMI: -0.15 [-0.22; -0.08]; WC: -0.62 [-0.88; -0.37]); age and lifestyle factors (BMI: -0.12 [-0.21; -0.04]); WC: -0.016 [-0.92; -0.29], age and occupational factors (BMI: -0.20 [-0.22; 0.08]; WC: -0.62 [-0.88; -0.36]), and age and psychological factors (BMI: -0.15 [-0.22; -0.07]; WC: -0.59 [-0.86; -0.33]). Among men, shorter sleep was also longitudinally associated with higher CMD risk scores in models adjusted for age and lifestyle factors (CMD: -0.12 [-0.20; -0.04]) and age and psychological factors (CMD: -0.08 [-0.15; -0.01]).

CONCLUSION

Corporate executives who report shorter sleep durations may present with poorer CMD risk profiles, independent of age, lifestyle, occupational and psychological factors. Addressing sleep health in workplace health programmes may help mitigate the development of CMD in such employees.

Association between Sleep Duration and Metabolic Disorders among Filipino Immigrant Women: The Filipino Women's Diet and Health Study (FiLWHEL)

Background

Sleep plays a complex role in metabolic regulation, and the underlying linkage has not been clearly defined. We investigated the association between sleep duration and metabolic disorders in Filipino immigrants in Korea.

Methods

We analyzed 410 participants from the 2014 to 2016 baseline population of the Filipino Women's Diet and Health Study. Usual sleep duration was self-reported, and anthropometric parameters were measured directly. Blood glucose, lipid, and insulin levels were examined from fasting serum samples. We used general linear models to acquire least squares (LS) means and logistic regression models to calculate odds ratios to test the cross-sectional association between sleep duration and metabolic markers with 95% confidence intervals (CIs).

Results

We found a statistically significant linear association between increased sleep duration and elevated triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C). LS means (95% CI) of <5, 5-6, 7-8, and >8 hours of sleep were 81.74 (71.43 to 93.54), 85.15 (76.65 to 94.59), 86.33 (77.84 to 95.75), and 105.22 (88.07 to 125.71), respectively, for triglycerides (P trend=0.049) and 174.52 (165.02 to 184.57), 180.50 (172.79 to 188.55), 182.51 (174.83 to 190.53), and 190.16 (176.61 to 204.74), respectively, for total cholesterol (P trend= 0.042). For LDL-C, the LS means (95% CI) were 97.34 (88.80 to 106.71), 100.69 (93.73 to 108.18), 104.47 (97.35 to 112.10), and 109.43 (96.94 to 123.54), respectively (P trend=0.047). Statistical significance persisted after additional adjustment for body mass index. The association with triglycerides was limited to current alcohol drinkers (P interaction=0.048).

Conclusion

Longer sleep duration was associated with increased triglyceride, total cholesterol, and LDL-C levels. The association with triglycerides was more pronounced among moderate alcohol drinkers.

Stress during Home Confinement Is Associated with Eating Misalignment among Adults during COVID-19 Lockdown

BACKGROUND

The COVID-19 pandemic forced Saudi Arabia to implement several measures including mandatory home confinement, banning entry to many cities, and suspending religious activities. Studies have reported inconsistent findings of the effect of home confinement on lifestyle factors. This study aims to assess the psychological impact of COVID-19 during home confinement and explore its association with dietary habits and weight change.

METHODS

A cross-sectional study was conducted among Saudi adults using an online survey between May and June 2020. Data on dietary habits, sleep quality, and stress were collected.

RESULTS

A total of n = 503 participants responded. Of 254 analyzed, 87% were females, 49% were overweight/obese (body mass index (BMI) ≥ 25 kg/m2), and 79% were under lockdown for >40 days. In multiple linear regression, higher stress scores during confinement were associated with higher stress scores before confinement and poorer sleep quality. In multiple logistic regression, those who did not eat at the same time had higher stress scores compared to those who always ate at the same time, whereas consuming ≥three meals was associated with lower stress scores than consuming one-two meals. The odds of gaining weight during confinement were higher among married adults, those with lower sleep quality, and consuming ≥three meals.

CONCLUSIONS

Stress during home confinement was associated with eating misalignment and the number of meals consumed. Although this study was limited by its cross-sectional design and reliance on self-reported data, it provides valuable insights into the dietary habits and weight-gain associated factors that need to be further explored and addressed in any future restrictions for improved well-being.

An Examination of the Associations between Nutritional Composition, Social Jet Lag and Temporal Sleep Variability in Young Adults

While dietary intake has previously been related to various indices of poor sleep (e.g., short sleep duration, poor sleep quality), to date, few studies have examined chrononutrition from the perspectives of the relationship between dietary intake and social jet lag and temporal sleep variability. Moreover, recently it has been suggested that previous methods of measuring social jet lag have the potential to lead to large overestimations. Together, this precludes a clear understanding of the role of nutritional composition in the pathophysiology of poor sleep, via social jet lag and temporal sleep variability, or vice versa. The aim of the present study was to determine the relationships between nutrient intake and social jet lag (using a revised index, taking account of intention to sleep and sleep onset and offset difficulties), and temporal sleep variability. Using a cross-sectional survey, 657 healthy participants (mean age 26.7 ± 6.1 years), without sleep disorders, were recruited via an online platform and completed measures of weekly dietary intake, social jet lag, temporal sleep variability, stress/sleep reactivity and mood. Results showed limited associations between nutritional composition and social jet lag. However, levels of temporal sleep variability were predicted by consumption of polyunsaturated fats, sodium, chloride and total energy intake. The results suggest further examinations of specific nutrients are warranted in a first step to tailoring interventions to manage diet and temporal variabilities in sleep patterns.

Inflammatory hypotheses of sleep disturbance - depression link: Update and research agenda

Studies in human and experimental animal models support a role of inflammation in the aetiology of depression, yet the precise role played by sleep disturbance (i.e., difficulties falling or maintaining sleep) is poorly understood. Consistent evidence from prospective epidemiological studies suggests sleep disturbance as a predictor of major depression episodes and depression recurrence. In parallel, up to 20% of individuals with sleep disturbance have low-grade peripheral inflammation (i.e., CRP>3 mg/l), and preliminary longitudinal evidence showed that sleep disturbance may even predict the levels of inflammation. Therefore, it is possible that sleep disturbance may increase inflammation, which in turn may contribute (i.e., mediate) to the onset - or worsening - of depression. Alternatively, sleep disturbance may serve as a vulnerability factor and increase the risk of developing depressive symptoms when facing an immune challenge. The aim of this review was to summarise the state of the science on the role of sleep disturbance in contributing to depression-related inflammation. A research agenda is also proposed to advance the study of sleep disturbance in the psychoneuroimmunology of depression.

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.

Pediatric sleep: current knowledge, gaps, and opportunities for the future

This White Paper addresses the current gaps in knowledge, as well as opportunities for future studies in pediatric sleep. The Sleep Research Society's Pipeline Development Committee assembled a panel of experts tasked to provide information to those interested in learning more about the field of pediatric sleep, including trainees. We cover the scope of pediatric sleep, including epidemiological studies and the development of sleep and circadian rhythms in early childhood and adolescence. Additionally, we discuss current knowledge of insufficient sleep and circadian disruption, addressing the neuropsychological impact (affective functioning) and cardiometabolic consequences. A significant portion of this White Paper explores pediatric sleep disorders (including circadian rhythm disorders, insomnia, restless leg and periodic limb movement disorder, narcolepsy, and sleep apnea), as well as sleep and neurodevelopment disorders (e.g. autism and attention deficit hyperactivity disorder). Finally, we end with a discussion on sleep and public health policy. Although we have made strides in our knowledge of pediatric sleep, it is imperative that we address the gaps to the best of our knowledge and the pitfalls of our methodologies. For example, more work needs to be done to assess pediatric sleep using objective methodologies (i.e. actigraphy and polysomnography), to explore sleep disparities, to improve accessibility to evidence-based treatments, and to identify potential risks and protective markers of disorders in children. Expanding trainee exposure to pediatric sleep and elucidating future directions for study will significantly improve the future of the field.

Association between hemoglobin adducts of ethylene oxide levels and the risk of short sleep duration in the general population: an analysis based on the National Health and Nutrition Examination Survey

This study aimed to evaluate the association between blood ethylene oxide (HbEtO) levels and short sleep duration (SSD). Data of 3438 participants aged 20 years or older in this study were collected from the National Health and Nutrition Examination Survey (NHANES). The ethylene oxide (EtO) biomarker (HbEtO) was quantified in blood using a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method. SSD was defined as sleep time equal to or less than 6 h. The analyses utilized weighted logistic regression models and restricted cubic spline. There was a significant non-linear relationship between HbEtO levels and the risk of SSD (P for-nonlinearity = 0.035). After the full adjustment for confounders, compared with the lowest quantile, the odds ratios (ORs) with 95% confidence intervals (CIs) of SSD across the quantiles of ethylene oxide levels were 1.54(1.09-2.18), 1.15(0.87-1.53), and 1.80(1.11-2.92), respectively (P for trend < 0.05). In subgroup analysis, people who were female, who were non-Hispanic Black, who never engaged in physical activity, who consumed alcohol ≤ 14 g/day, who were normal weight or obese had a significantly higher risk of SSD when they had highest quartiles of HbEtO levels than those had lowest (p < 0.05). Our study indicated that HbEtO levels, an indicator for EtO exposure, were associated with SSD in general adult populations.

Sleep Deprivation Promotes Endothelial Inflammation and Atherogenesis by Reducing Exosomal miR-182-5p

BACKGROUND

Insufficient or disrupted sleep increases the risk of cardiovascular disease, including atherosclerosis. However, we know little about the molecular mechanisms by which sleep modulates atherogenesis. This study aimed to explore the potential role of circulating exosomes in endothelial inflammation and atherogenesis under sleep deprivation status and the molecular mechanisms involved.

METHODS

Circulating exosomes were isolated from the plasma of volunteers with or without sleep deprivation and mice subjected to 12-week sleep deprivation or control littermates. miRNA array was performed to determine changes in miRNA expression in circulating exosomes.

RESULTS

Although the total circulating exosome levels did not change significantly, the isolated plasma exosomes from sleep-deprived mice or human were a potent inducer of endothelial inflammation and atherogenesis. Through profiling and functional analysis of the global microRNA in the exosomes, we found miR-182-5p is a key exosomal cargo that mediates the proinflammatory effects of exosomes by upregulation of MYD88 (myeloid differentiation factor 88) and activation of NF-ĸB (nuclear factor kappa-B)/NLRP3 pathway in endothelial cells. Moreover, sleep deprivation or the reduction of melatonin directly decreased the synthesis of miR-182-5p and led to the accumulation of reactive oxygen species in small intestinal epithelium.

CONCLUSIONS

The findings illustrate an important role for circulating exosomes in distant communications, suggesting a new mechanism underlying the link between sleep disorder and cardiovascular disease.

The interrelationship between sleep, diet, and glucose metabolism

Obesity and type 2 diabetes (T2D) are increasingly common worldwide. While these disorders have increased in prevalence over the past several decades, there has been a concomitant reduction in sleep duration. Short sleep duration has been associated with higher rates of obesity and T2D, and the causality of these associations and their directionality, continue to necessitate evaluation. In this review we consider the evidence that sleep is an intrinsic factor in the development of obesity and chronic metabolic disorders, such as insulin resistance and T2D, while evaluating a potential bi-directional association. We consider the evidence that diet and meal composition, which are known to impact glycemic control, may have both chronic and acute impact upon sleep. Moreover, we consider that postprandial nocturnal metabolism and peripheral glycemia may affect sleep quality. We propose putative mechanisms whereby acute effects of nighttime glucose excursions may lead to increased sleep fragmentation. We conclude that dietary manipulations, particularly with respect to carbohydrate quality, may confer sleep benefits. Future research may seek to evaluate the effectiveness of synergistic nutrient strategies to promote sleep quality, with particular attention to carbohydrate quality, quantity, and availability as well as carbohydrate to protein ratio.

The association between sleep duration and detailed measures of obesity: A cross sectional analysis in the ADDITION-PRO study

Background

Sleep duration is associated with BMI and waist circumference. However, less is known about whether sleep duration affects different measurements of obesity differently.

Objective

To investigate the association between sleep duration and different measures of obesity.

Methods

In this cross-sectional analysis 1309, Danish, older adults (55% men) completed at least 3 days of wearing a combined accelerometer and heart rate-monitor for assessing sleep duration (hours/night) within self-reported usual bedtime. Participants underwent anthropometry and ultrasonography to assess BMI, waist circumference, visceral fat, subcutaneous fat, and fat percentage. Linear regression analyses examined the associations between sleep duration and obesity-related outcomes.

Results

Sleep duration was inversely associated with all obesity-related outcomes, except visceral-/subcutaneous-fat-ratio. After multivariate adjustment the magnitude of associations became stronger and statistically significant for all outcomes except visceral-/subcutaneous-fat-ratio, and subcutaneous fat in women. The associations with BMI and waist circumference demonstrated the strongest associations, when comparing standardized regression coefficients.

Conclusions

Shorter sleep duration were associated with higher obesity across all outcomes except visceral-/subcutaneous-fat-ratio. No specifically salient associations with local or central obesity were observed. Results suggest that poor sleep duration and obesity correlate, however, further research is needed to conclude on beneficial effects of sleep duration regarding health and weight loss.

Lifestyle Changes during the SARS-CoV-2 Pandemic as Predictors of BMI Changes among Men and Women in Poland

BACKGROUND

Social isolation during the SARS-CoV-2 pandemic affected people's body weight, therefore, this study was designed to evaluate the association between lifestyle elements and the change in BMI during lockdown.

METHODS

This retrospective observational study involved 290 questionnaires completed by adult participants divided into three groups according to BMI change during isolation. The structured questionnaire included a general description of the study objective and collected data regarding sociodemographics, anthropometrics, physical activity, sedentary behaviour, sleep duration, and food intake pre- and during COVID-19 lockdown.

RESULTS

A decrease or increase in BMI was found in 23.6% and 47.8% of women and 18.5% and 42.6% of men, respectively. Among those who lost weight, 46.5% of women and 40% of men followed a diet of their own choice, 30.2% of women and 25% of men changed their product mix and reduced their intake, 40% of men stopped eating outside the home. An increase in BMI was associated with increased food intake (32.2% of women and 28.3% of men), increased sleep duration on weekdays (49.2% of women and 43.5% of men) and, in more than 50% of subjects, decreased physical activity. In women, increased BMI was associated with the highest frequency of snacking (p = 0.0003), the highest intake of sweets (p = 0.0021), and in men with the highest intake of alcohol (p = 0.0017).

CONCLUSIONS

The observed changes in BMI during social isolation were the result of lifestyle modifications including dietary behaviour and differed by gender.

The course of insomnia symptoms during the acute treatment of major depressive disorder: A CAN-BIND-1 report

Despite considerable efforts to study the relationship between insomnia and depression, there is minimal research investigating whether insomnia symptoms change over time during a course of antidepressant pharmacotherapy. This study investigated the course of insomnia symptoms during the acute treatment of major depressive disorder (MDD) using a secondary analysis of data from MDD patients (N = 180) who were treated with open-label escitalopram (10-20 mg/day) for 8-weeks. Montgomery-Asberg Depression Rating Scale without sleep item (modified-MADRS) assessed depression and Self-reported Quick Inventory Depressive Scale (QIDS-SR) measured subjective sleep-onset, mid-nocturnal, and early-morning insomnia throughout 8-weeks of treatment. Pittsburgh Sleep Quality Index (PSQI) was used to assess subjective sleep quality, duration, onset latency, and efficiency throughout 8-weeks of treatment. Remission of depression was defined as modified-MADRS ≤10 at week-8. Mixed model repeated measures (MMRMs) were conducted with remission status as an independent variable and each sleep variable as a dependent variable. MMRMs demonstrated that remitters had significantly lower QIDS-SR sleep-onset and mid-nocturnal insomnia scores as well as a significantly lower PSQI sleep quality score than non-remitters throughout 8-weeks of treatment. Monitoring subjective sleep-onset and mid-nocturnal insomnia during the course of treatment with serotonergic antidepressants may be useful for predicting acute remission of depression.

Temporal relationship between sleep duration and obesity among Chinese Han people and ethnic minorities

BACKGROUND

No studies have assessed the association between sleep duration and obesity in Chinese ethnic minorities. Whether the relationship between sleep duration and obesity is different between Chinese Han people and Chinese ethnic minorities remains unclear. The study aimed to explore the relationship between sleep duration and obesity among Chinese Han people and Chinese ethnic minorities.

METHODS

We applied data from the Guizhou Population Health Cohort Study (GPHCS), which 9,280 participants were recruited in the baseline survey from 2010 to 2012, and 8,163 completed the follow-up survey from 2016 to 2020. A total of 5,096 participants (3,188 Han Chinese and 1,908 ethnic minorities) were included in the ultimate analysis. Information on sleep duration (total 24-hour sleep time), body mass index (BMI), and waist circumference (WC) was collected at the baseline and follow-up survey, respectively. Cross-lagged panel analyses were conducted to explore the temporal relationship between sleep duration and obesity for Han people and ethnic minorities.

RESULTS

For Han people, the results from cross-lagged panel analyses indicated that baseline sleep duration was significantly associated with follow-up BMI (β_BMI = -0.041, 95% CI_BMI: -0.072 ~ -0.009) and follow-up WC (β_WC = -0.070, 95%CI_WC: -0.103 ~ -0.038), but baseline BMI (β_BMI = -0.016, 95% CI_BMI: -0.050 ~ 0.018) and baseline WC (β_WC = -0.019, 95% CI_WC: -0.053 ~ 0.016) were not associated with follow-up sleep duration. In addition, the relationship between baseline sleep duration and follow-up BMI was gender-specific and significant only in the Han people female (β_BMI = -0.047, 95% CI_BMI: -0.090 ~ -0.003) but not in the Han people male (β_BMI = -0.029, 95% CI_BMI: -0.075 ~ 0.016). For ethnic minorities, the results indicated that there was no relationship between sleep duration and obesity at all, either from sleep duration to obesity (β_BMI = 0.028, 95%CI_BMI: -0.012 ~ 0.068; β_WC = 0.020, 95%CI_WC: -0.022 ~ 0.062), or from obesity to sleep duration (β_BMI = -0.022, 95%CI_BMI: -0.067 ~ 0.022; β_WC = -0.042, 95%CI_WC: -0.087 ~ 0.003).

CONCLUSION

The relationship pattern between sleep duration and obesity across Han people and ethnic minorities is different. Future sleep-aimed overweight and obesity intervention should be conducted according to population characteristics.

Habitual night sleep duration is associated with general obesity and visceral obesity among Chinese women, independent of sleep quality

Purpose

Research on the relationship between sleep duration and obesity defined using multiple anthropometric and bioelectrical indices in women remains scarce. We aimed to explore the association between sleep duration and body mass index (BMI), waist-hip ratio (WHR), body fat percentage (PBF) and visceral fat area (VFA) among females.

Methods

We recruited women for medical examination using multistage cluster sampling. Sleep was assessed using Pittsburgh Sleep Quality Index (PSQI) and sleep duration was categorized into short (<7 h), optimal (7 <9 h) and long sleep (≥ 9 h). Weight and height were measured using a calibrated stadiometer. Waist circumference was manually measured. PBF, and VFA were estimated by bioelectrical impedance analysis. Data on sociodemographic characteristics and lifestyle factors were also collected and included in the logistic regression models to explore the independent association between sleep duration and obesity defined by different indices.

Results

A total of 7,763 women with a mean age of 42.6 ± 13.5 years were included. The percentage of women reporting short and long sleep was 10.3 and 13.4% respectively. The mean BMI, WHR, PBF and VFA were 23.07 ± 3.30 kg/m², 0.78 ± 0.06, 32.23 ± 6.08% and 91.64 ± 35.97cm², respectively. Short sleep was independently associated with 35% (95% CI: 1.05-1.75) increased odds of general obesity (BMI ≥ 28 kg/cm²), and long sleep was associated with 18% (95% CI: 1.01-1.37) increased odds of visceral obesity (VFA > 100 cm²). No association was observed between sleep deprivation or excessive sleep and high WHR or high PBF.

Conclusion

In women, short sleep was associated with an increased odds of general obesity, whereas long sleep was associated with an increased odds of visceral obesity. Longitudinal observations are needed to confirm this cross-sectional relationship.

Sleep is increased by liraglutide, a glucagon-like peptide-1 receptor agonist, in rats

INTRODUCTION

Sleep disturbances are prominent in drug use disorders, including those involving opioids in both humans and animals. Recent studies have shown that administration of liraglutide, a glucagon-like peptide-1 agonist, significantly reduces heroin taking and seeking in rats. In an effort to further understand the action of this substance on physiological functions and to evaluate safety issues for its potential clinical use, the aim of the present study was to determine whether the dose of liraglutide found effective in reducing responding for an opioid also could improve sleep in drug-naïve rats.

METHODS

Using a within-subjects design, adult male rats chronically implanted with EEG and EMG electrodes received subcutaneous injection of saline or 0.06, 0.10, 0.30 or 0.60 mg/kg liraglutide. The 0.10 and 0.30 mg/kg doses are known to be most effective in reducing responding for heroin in rats at light or dark onset during a 12:12 h light-dark cycle (0.10 mg/kg for taking and seeking, 0.30 mg/kg for seeking). EEG and EMG were recorded across the 24 h period following each injection.

RESULTS

After both dark and light onset injections, liraglutide dose-dependently decreased wakefulness and increased non-rapid eye movement (NREM) sleep except at the lowest dose. The bout length of wakefulness and NREM sleep were decreased and increased, respectively. Whether administered at light or dark onset, the above alterations occurred primarily during the dark period (i.e., during the active period). The animals' body weight was decreased after liraglutide treatments as expected since it is clinically used for the treatment of obesity.

CONCLUSION

These data indicate that liraglutide, at doses known to reduce responding for heroin and fentanyl, also increases NREM sleep, suggesting that the increase in sleep may contribute to the protective effects of liraglutide and may promote overall general health.

Variability in Sleep Timing and Dietary Intake: A Scoping Review of the Literature

The objective of this scoping review was to summarize previous studies which examined the effect of day-to-day variability in sleep timing and social jetlag (SJL) on dietary intake. A systematic literature search was conducted in PubMed, Embase, and Clarivate Analytics Web of Science and we identified 22 records. No difference in caloric and macronutrient intake between SJL groups was observed in studies that enrolled healthy young adults. However, studies that enrolled participants with obesity and obesity-related chronic conditions reported a higher caloric intake and a higher intake of carbohydrates, total fat, saturated fats, and cholesterol in participants with SJL than in those without. Most studies reported a lower quality of diet, a delayed mealtime, and eating jetlag in participants with SJL vs. those without SJL. No correlation of day-to-day variability in sleep timing with average caloric intake was observed, but bed-time variability was negatively associated with diet quality. Methodological issues have been identified in sources assessed including study design, power calculation, population enrolled, and tools/metrics used for sleep timing variability assessment. Future well powered longitudinal studies, with clear protocols, standardized metrics, including all age groups from general population are needed to clarify the dietary intake consequences of variability in sleep timing.

Non-alcoholic fatty liver disease (NAFLD) and mental illness: Mechanisms linking mood, metabolism and medicines

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the world and one of the leading indications for liver transplantation. It is one of the many manifestations of insulin resistance and metabolic syndrome as well as an independent risk factor for cardiovascular disease. There is growing evidence linking the incidence of NAFLD with psychiatric illnesses such as schizophrenia, bipolar disorder and depression mechanistically via genetic, metabolic, inflammatory and environmental factors including smoking and psychiatric medications. Indeed, patients prescribed antipsychotic medications, regardless of diagnosis, have higher incidence of NAFLD than population norms. The mechanistic pharmacology of antipsychotic-associated NAFLD is beginning to emerge. In this review, we aim to discuss the pathophysiology of NAFLD including its risk factors, insulin resistance and systemic inflammation as well as its intersection with psychiatric illnesses.

The impact of social rhythm and sleep disruptions on waist circumference after job loss: A prospective 18-month study

OBJECTIVE

This study prospectively examined change in waist circumference (WC) as a function of daily social rhythms and sleep in the aftermath of involuntary job loss. It was hypothesized that disrupted social rhythms and fragmented/short sleep after job loss would independently predict gains in WC over 18 months and that resiliency to WC gain would be conferred by the converse.

METHODS

Eligible participants (n = 191) completed six visits that included standardized measurements of WC. At the baseline visit, participants completed the social rhythm metric and daily sleep diary and wore an actigraph on their nondominant wrist each day for a period of 2 weeks.

RESULTS

When controlling for obesity and other covariates, WC trajectories decreased for individuals with more consistent social rhythms, more activities in their sdiocial rhythms, and higher sleep quality after job loss. WC trajectories did not change for individuals with lower scores on these indicators.

CONCLUSIONS

The frequency and consistency of social rhythms after job loss play a key role in WC loss. These findings support the implementation of social rhythm interventions after job loss, a potentially sensitive time for the establishment of new daily routines that have an impact on metabolic health.

Short sleep and social jetlag are associated with higher intakes of non-milk extrinsic sugars, and social jetlag is associated with lower fibre intakes in those with adequate sleep duration: a cross-sectional analysis from the National Diet and Nutrition Survey Rolling Programme (Years 1-9)

OBJECTIVE

To investigate associations and interactions between sleep duration and social jetlag status with nutrient intake, nutrient status, body composition and cardio-metabolic risk factors in a nationally representative UK adult population.

DESIGN

A cross-sectional study using 4-d food diary and self-reported sleep data from the UK National Diet and Nutrition Survey Rolling Programme 2008-2017.

SETTING

UK free-living population.

SUBJECTS

Totally, 5015 adults aged 19-64 years.

RESULTS

Thirty-four per cent were short sleepers (< 7 h); 7 % slept ≥ 9 h; 14 % had > 2 h difference in average sleep duration between weeknights and weekend nights (social jetlag). Compared to those reporting optimal sleep duration (≥ 7-< 9 h), short sleep was associated with higher intakes of non-milk extrinsic sugars (NMES) (0·9 % energy, 95 % CI: 0·4, 1·4), total carbohydrate (0·8 % energy, 95 % CI: 0·2, 1·4) and a lower non-starch polysaccharides fibre intake (-0·5 g/d, 95 % CI -0·8, -0·2). There was a significant interaction between short sleep and social jetlag for fibre intakes, where adequate sleepers with social jetlag as well as all short sleepers (regardless of social jetlag) had lower fibre intakes than adequate sleepers with no social jetlag. Short sleep, but not social jetlag, was associated with greater adiposity, but there were no differences in other markers of cardiometabolic disease risk.

CONCLUSIONS

The present study reports that both short sleep and social jetlag are associated with higher intakes of NMES, but only sleep duration is associated with markers of adiposity. Social jetlag was associated with lower fibre intakes even in individuals with adequate weekly sleep duration, suggesting catch-up sleep does not prevent the adverse impact of irregular sleep habits on food choices.

Sleep disturbances in early clinical stages of psychotic and bipolar disorders: A meta-analysis

OBJECTIVE

To provide a qualitative view and quantitative measure of sleep disturbances across and between early stages - clinical ultra high-risk and first episode - of psychotic and bipolar disorders.

METHODS

Electronic databases (PubMed, Cochrane, Embase, PsychINFO) were searched up to March 2021 for studies comparing sleep measures between individuals with an early stage and controls. Standard mean deviations (Cohen's d effect sizes) were calculated for all comparisons and pooled with random-effects models. Chi-square tests were used for direct between-subgroups (ultra high-risk vs first episode) comparisons of standard mean deviations. The effects of age, sex ratio, symptoms and treatment were examined in meta-regression analyses.

RESULTS

A database search identified 13 studies that contrasted sleep measures between individuals with an early stage (N = 537) and controls (N = 360). We observed poorer subjective sleep quality (standard mean deviation = 1.32; 95% confidence interval, [1.01, 1.62]), shorter total sleep time (standard mean deviation =-0.44; 95% confidence interval, [-0.67, -0.21]), lower sleep efficiency (standard mean deviation = -0.72; 95% confidence interval, [-1.08, -0.36]), longer sleep onset latency (standard mean deviation = 0.75; 95% confidence interval, [0.45, 1.06]) and longer duration of wake after sleep onset (standard mean deviation = 0.49; 95% confidence interval, [0.21, 0.77]) were observed in early stages compared to controls. No significant differences were observed for any of the reported electroencephalographic parameters of sleep architecture. No significant between-subgroups differences were observed. Meta-regressions revealed a significant effect of the age and the antipsychotic status on subjective measures of sleep.

CONCLUSION

The early stage population presents with significant impairments of subjective sleep quality continuity, duration and initiation. Systematic assessments of sleep in early intervention settings may allow early identification and treatment of sleep disturbances in this population.

Shift Work and Obesity Risk-Are There Sex Differences?

PURPOSE OF REVIEW

Shift work is prevalent among the working population and is linked to an array of adverse health outcomes. This review summarizes current evidence on the relation between shift work and risk of obesity, with a particular emphasis on potential sex differences.

RECENT FINDINGS

Observational data strongly point towards an association between shift work and heightened risk of prevalent and incident obesity, and particularly abdominal obesity. Circadian misalignment and unhealthy lifestyle behaviors are the primary culprits mediating such association. As it pertains to sex differences in the impact of shift work on obesity, few studies have examined this aspect, and findings are conflicting. Shift work is an important risk factor for obesity, with likely multiple biological and behavioral mediators. However, whether there is a sex-dependent vulnerability to the obesogenic effects of shift work is unclear. This area presents opportunities for future research.

Short Sleep Duration Was Associated with Increased Regional Body Fat in US Adults: The NHANES from 2011 to 2018

Background: The relationship between sleep duration and different regional fat is unclear. We aimed to investigate the association between sleep duration and different regional fat mass (FM) among a population of US adults. Methods: 9413 participants were included from the National Health and Nutrition Examination Survey (NHANES), from 2011 to 2018. The sleep duration was divided into short sleep (<7 h/day), normal sleep (7−9 h/day) and long sleep (>9 h/day). Different regional FM was measured by dual-energy X-ray absorptiometry, including trunk FM, arms FM and legs FM. Fat mass index (FMI) was obtained by dividing FM (kg) by the square of body height (m2). Multiple linear regression was used to evaluate the relationship between sleep duration and regional FMI. Results: The mean sleep duration was 7.1 ± 1.5 h/day. After adjusting for socio-demographic, lifestyle information, comorbid diseases and medications, short sleepers had higher trunk FMI (β = 0.134, 95% confidence interval (CI): 0.051−0.216, p = 0.001), arms FMI (β = 0.038, 95% CI: 0.016−0.06, p < 0.001) and legs FMI (β = 0.101, 95% CI: 0.044−0.158, p < 0.001) compared to normal sleepers, whereas no significant difference was found in long sleepers. The similar results were also observed in men, while short sleepers only had higher arms FM in women (all p < 0.01). In addition, compared to normal sleepers, short sleepers had higher arms FMI and legs FMI in the obese group (all p < 0.05), while no relationship was observed in non-obese group. Conclusions: Short sleep duration, but not long sleep duration, was independently related to the increased different regional body fat in US adults, especially in men and those with obesity.

Psychological Profiles of Treatment-Seeking Adults with Overweight and Obesity: A Cluster Analysis Approach

BACKGROUND

Overweight and obesity are associated with depression and well-being. Some psychological characteristics play a role in explaining well-being and depression in obesity and in identifying specific patient profiles. However, subtyping individuals with overweight/obesity based on variables like self-esteem or stress has not often been done. Therefore, our objective was to explore the psychological profiles of treatment-seeking individuals overweight or with obesity and to compare their depression and well-being.

METHODS

Data regarding eating self-efficacy, well-being, depression, physical hunger, self-esteem, body satisfaction and perceived stress in individuals with overweight/obesity were collected from the ESTEAM cohort. Hierarchical cluster analysis and mean comparisons were performed on female (n = 1427) and male samples (n = 310).

RESULTS

Three psychological profiles were identified in both samples. The "High psychological concerns" profile and the "Low psychological concerns" profile were identical in both samples. The third profile, "Bodily concerns", differed by sex and was characterized by appearance dissatisfaction for women and by appearance and eating concerns for men. The "Low psychological concerns" profile presented the highest well-being and the lowest depression scores in both samples.

DISCUSSION

The findings support the hypothesis of the heterogeneity of individuals with overweight and obesity and suggest sex-related therapeutic approaches.

Prospective Associations Between Fathers' Engagement in Infant Caregiving and Their Weight-Related Behaviors and Mental Health

Fathers’ engagement in infant caregiving is linked with positive social, emotional, and developmental outcomes in children; however, its relationship with fathers’ own health is largely unknown. This longitudinal study examined associations between fathers’ caregiving engagement with their 6-month-old infants and their physical activity, sugar-sweetened beverage (SSB) consumption, nighttime sleep duration, and depressive symptoms 6 months later when infants were 12 months old. Participants were 143 fathers of infants (62.7% non-Hispanic White, 82.3% with a bachelor’s degree). Fathers reported their frequency of engagement in seven caregiving activities when infants were 6 months old. Fathers’ physical activity, SSB consumption, nighttime sleep duration, and depressive symptoms were assessed when infants were 6 and 12 months old. Multivariate logistic regression analysis was used to assess if fathers who reported higher infant caregiving at 6 months had more positive health outcomes at 12 months, controlling for fathers’ age, race/ethnicity, education, employment, household income, and the outcome at 6 months. Fathers who reported higher caregiving engagement when infants were 6 months old had increased odds of being sufficiently physically active 6 months later (unadjusted odds ratio [OR] = 1.19, 95% confidence interval [CI] = [1.00, 1.41]; adjusted OR = 1.47, 95% CI = [1.11, 1.96]). No links were identified between fathers’ caregiving engagement and their SSB consumption, nighttime sleep duration, or depressive symptoms. In summary, fathers’ engagement in infant caregiving may be beneficial to their physical activity in the first year after birth. There was insufficient evidence in this study that the benefits of caregiving engagement were experienced broadly across multiple health outcomes.

Disruption of the circadian rhythms and its relationship with pediatric obesity

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

The Effect of Short Sleep Duration on the Development of Asthma

Asthma is regarded as a heterogeneous disease with chronic airway inflammation and reversible airway limitation. Asthma itself and recurrent attacks of asthma can decrease sleep duration and increase the prevalence of short sleep duration. Systemic low-grade inflammation and obesity caused by short sleep duration have been known for a long time, which potentially affect the development of asthma. It would be interesting to study the interaction between short sleep duration and asthma. However, there are relatively few studies and no review about the association between short sleep duration and asthma. This article performed a review about the relationships between short sleep duration and asthmatic phenotype, laboratory tests, comorbidity, and clinical outcomes. Pooled studies about short sleep duration and asthma provided following four results: (1) compared with healthy sleep duration, short sleep duration seemingly increased the risk of central obesity in asthmatics; (2) short sleep duration potentially reduced the level of FeNO and increased lung function impairment in patients with asthma; (3) asthmatic comorbidities, mainly obesity and depression, were negatively associated with short sleep duration among asthmatics; (4) short sleep duration potentially increased the risks of asthma-related hospitalization and emergency care. However, almost all studies are based on subjective but not objective sleep duration. In addition, the study on sleep duration and cause-specific mortality in patients with asthma is relatively scant. Considering the effect of short sleep duration on the development of asthma, we recommend that periodic sleep monitoring for asthmatic management is very necessary.

Mechanisms of Melatonin in Obesity: A Review

Obesity and its complications have become a prominent global public health problem that severely threatens human health. Melatonin, originally known as an effective antioxidant, is an endogenous hormone found throughout the body that serves various physiological functions. In recent decades, increasing attention has been paid to its unique function in regulating energy metabolism, especially in glucose and lipid metabolism. Accumulating evidence has established the relationship between melatonin and obesity; nevertheless, not all preclinical and clinical evidence indicates the anti-obesity effect of melatonin, which makes it remain to conclude the clinical effect of melatonin in the fight against obesity. In this review, we have summarized the current knowledge of melatonin in regulating obesity-related symptoms, with emphasis on its underlying mechanisms. The role of melatonin in regulating the lipid profile, adipose tissue, oxidative stress, and inflammation, as well as the interactions of melatonin with the circadian rhythm, gut microbiota, sleep disorder, as well as the α7nAChR, the opioidergic system, and exosomes, make melatonin a promising agent to open new avenues in the intervention of obesity.

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.

Role of sleep deprivation in immune-related disease risk and outcomes

Modern societies are experiencing an increasing trend of reduced sleep duration, with nocturnal sleeping time below the recommended ranges for health. Epidemiological and laboratory studies have demonstrated detrimental effects of sleep deprivation on health. Sleep exerts an immune-supportive function, promoting host defense against infection and inflammatory insults. Sleep deprivation has been associated with alterations of innate and adaptive immune parameters, leading to a chronic inflammatory state and an increased risk for infectious/inflammatory pathologies, including cardiometabolic, neoplastic, autoimmune and neurodegenerative diseases. Here, we review recent advancements on the immune responses to sleep deprivation as evidenced by experimental and epidemiological studies, the pathophysiology, and the role for the sleep deprivation-induced immune changes in increasing the risk for chronic diseases. Gaps in knowledge and methodological pitfalls still remain. Further understanding of the causal relationship between sleep deprivation and immune deregulation would help to identify individuals at risk for disease and to prevent adverse health outcomes.