Gene-by-environment interactions of the CLOCK, PEMT, and GHRELIN loci with average sleep duration in relation to obesity traits using a cohort of 643 New Zealand European children

Accelerometry-assessed sleep clusters and obesity in adolescents and young adults: a longitudinal analysis in GINIplus/LISA birth cohorts

BACKGROUND

Some studies have revealed various sleep patterns in adolescents and adults using multidimensional objective sleep parameters. However, it remains unknown whether these patterns are consistent from adolescence to young adulthood and how they relate to long-term obesity.

METHODS

Seven-day accelerometry was conducted in German Infant Study on the influence of Nutrition Intervention PLUS environmental and genetic influences on allergy development (GINIplus) and Influence of Lifestyle factors on the development of the Immune System and Allergies in East and West Germany (LISA) birth cohorts during the 15-year and 20-year follow-ups, respectively. Five sleep clusters were identified by k-means cluster analysis using 12 sleep characteristics at each follow-up. Adjusted linear and logistic regression models using generalized estimating equations were examined. Further, the interaction effects with time of follow-ups and polygenic risk scores (PRS) for body mass index (BMI) were tested.

RESULTS

Five sleep clusters were classified consistently in both adolescence (n = 1347, aged 14.3-16.4 years) and young adulthood (n = 1262, aged 19.5-22.4 years). Adolescents in the "good sleep", "delayed sleep phase", and "fragmented sleep" clusters displayed greater stability transitioning into young adulthood, while those in the "sleep irregularity and variability", and "prolonged sleep latency" clusters showed lower stability (n = 636). Compared to the "good sleep" cluster, the "prolonged sleep latency" cluster exhibited associations with higher BMI [β = 0.56, 95% confidence interval (CI) = (0.06, 1.05)] and increased odds of overweight/obesity [Odds ratio = 1.55, 95% CI = (1.02, 2.34)]. No significant PRS-sleep cluster interaction was found for BMI or overweight/obesity. Among males only, the "delayed sleep phase", "sleep irregularity and variability" and "fragmented sleep" clusters showed stronger associations with overweight/obesity as age increased.

CONCLUSION

Adolescents and young adults shared five consistent sleep patterns, with the "prolonged sleep latency" pattern linked to higher BMI and overweight/obesity.

Interaction of Clock gene variants and behavioral parameters influences adiposity-related traits

Obesity, a major health concern, is influenced by an individual's genetic makeup and lifestyle factors (eating, sedentary lifestyle, and sleep disruptions) that affect circadian clock and metabolism. This study investigates the impact of Clock gene variants rs6843722 and rs4864548 on obesity measures in the Pakistani population. Genetic-behavior interaction studies have focused on Western populations, overlooking South Asians. We included 306 overweight/obese and 306 normal-weight controls, matched for age and gender. Anthropometric measures (BMI, waist circumference, waist-to-height ratio, and body fat percentage) were taken using standard procedures while behavioral data (dietary and sleep-related behaviors, shiftwork, and physical activity) was collected by questionnaire. Genotyping was performed by Taqman assays. Data was analyzed using SPSS 19.0. Rank-based inverse normal transformation was executed for quantitative non-normal variables. The linear regression revealed that both Clock gene variants interacted significantly with dietary and sleep-related behaviors and low physical activity, impacting adiposity measures regardless of age and gender. Shiftwork interacted specifically with rs6843722, increasing body fat percentage. This study indicates that Clock gene variants, when interacting with lifestyle factors, play a substantial role in increasing obesity risk highlighting the link between lifestyle choices and disturbances in circadian rhythms controlled by Clock gene variations, ultimately leading to obesity.

Comparison of actigraphy-measured and parent-reported sleep in association with weight status among preschool children

This study compared weekday and weekend actigraphy-measured and parent-reported sleep in relation to weight status among preschool-aged children. Participants were 3-6 years old preschoolers from the cross-sectional DAGIS-study with sleep data for ≥2 weekday and ≥2 weekend nights. Parents-reported sleep onset and wake-up times were gathered alongside 24 h hip-worn actigraphy. An unsupervised Hidden-Markov Model algorithm provided actigraphy-measured night time sleep without the guidance of reported sleep times. Waist-to-height ratio and age-and-sex-specific body mass index characterised weight status. Comparison of methods were assessed with consistency in quintile divisions and Spearman correlations. Associations between sleep and weight status were assessed with adjusted regression models. Participants included 638 children (49% girls) with a mean ± SD age of 4.76 ± 0.89. On weekdays, 98%-99% of actigraphy-measured and parent-reported sleep estimates were classified in the same or adjacent quintile and were strongly correlated (rs  = 0.79-0.85, p < 0.001). On weekends, 84%-98% of actigraphy-measured and parent-reported sleep estimates were respectively classified and correlations were moderate to strong (rs  = 0.62-0.86, p < 0.001). Compared with actigraphy-measured sleep, parent-reported sleep had consistently earlier onset, later wake-up, and greater duration. Earlier actigraphy-measured weekday sleep onset and midpoint were associated with a higher body mass index (respective β-estimates: -0.63, p < 0.01 and -0.75, p < 0.01) and waist-to-height ratio (-0.004, p = 0.03 and -0.01, p = 0.02). Though the sleep estimation methods were consistent and correlated, actigraphy measures should be favoured as they are more objective and sensitive to identifying associations between sleep timing and weight status compared with parent reports.

Rare Variants of Obesity-Associated Genes in Young Adults with Abdominal Obesity

The increase in the prevalence of overweight, obesity and associated diseases is a serious problem. The aim of the study was to identify rare variants in obesity-associated genes in young adults with abdominal obesity in our population and to analyze information about these variants in other populations. Targeted high-throughput sequencing of obesity-associated genes was performed (203 young adults with an abdominal obesity phenotype). In our study, all of the 203 young adults with abdominal obesity had some rare variant in the genes associated with obesity. The widest range of rare and common variants was presented in ADIPOQ, FTO, GLP1R, GHRL, and INS genes. The use of targeted sequencing and clinical criteria makes it possible to identify carriers of rare clinically significant variants in a wide range of obesity-associated genes and to investigate their influence on phenotypic manifestations of abdominal obesity.

Proportion of Chinese Children and Adolescents Meeting 24-Hour Movement Guidelines and Associations with Overweight and Obesity

Background: Since there is little knowledge about the 24-hour movement behaviors of Chinese children and adolescents, the purposes of this study were to investigate the proportion of Chinese children and adolescents meeting the 24-Hour Movement Guidelines and to further evaluate its relationship with overweight and obesity. Methods: A total of 440 children and adolescents aged 7−18 years from 7 cities in China were selected to measure physical activity using accelerometers, and sleep (SLP) and screen time (ST) using questionnaires. The data were analyzed with the independent T-test, Mann−Whitney U test, Cox−Stuart test, chi-square test, and logistic regression. Results: The proportion of Chinese children and adolescents meeting the overall 24-Hour Movement Guidelines was 7.3%. Boys (11.8%) were higher than girls (3.4%) (p < 0.001) and showed a downward trend with age (Ptrend = 0.03). The rates of overweight and obesity among children and adolescents who met the ST, MVPA + ST, ST + SLP, and MVPA + SLP + ST guidelines were 39%, 15%, and 36%, and 25% did not meet any guidelines. The rates of overweight and obesity among those who met 1, 2, and 3 guidelines were lower than the rate among those who did not meet any guidelines (odds ratio (OR) = 0.51, 95% confidence interval (CI): 0.22−1.17; OR = 0.32, 95% CI: 0.13−0.77; OR = 0.23, 95% CI: 0.07−0.81) and showed a decreasing trend (Ptrend = 0.006). Conclusions: The proportion of Chinese children and adolescents meeting the overall 24-Hour Movement Guidelines was low. The rate of overweight and obesity among children and adolescents who met the overall 24-Hour Movement Guidelines was the lowest compared with the rates among those who met any one or two. There was a dose−response relationship between the number of guidelines met and the overweight and obesity rate.

Association between CLOCK gene polymorphisms and ADHD in Mexican teenagers: A comprehensive assessment

This study aimed to evaluate markers of the CLOCK gene rs1801260 and rs4864548 in Mexican adolescents, addressing clinical and biological aspects previously associated with ADHD. 347 Mexican adolescents were assessed for mental disorders, metabolic disruption and related conditions, circadian preference, as well as genotyping for the CLOCK. We found a significant association between ADHD and the AA and AG genotypes of rs1801260. Also, we identified in the ADHD group that the total Triiodothyronine and total Thyroxine values were respectively 10 ng/dl units and 0.58 ug/dl units lower in females than in males. Previously reported common variations of the CLOCK gene have been associated with ADHD like the Rs1801260 polymorphism hereby we could consider it as risk factor, but genetic, biochemical and clinical studies in the Mexican population are entailed.

Association of CLOCK gene variants with obesity and adiposity-related anthropometric, metabolic, and behavioral parameters

The CLOCK gene is a core component of the circadian clock and regulates various aspects of metabolism. Therefore, any variation that affects the function/expression of the CLOCK gene may contribute to the manifestation of metabolic disorders such as obesity. This study investigated whether the CLOCK variants rs4864548 and rs6843722 are associated with obesity and related traits in Pakistanis. A total of 306 overweight/obese cases and 306 age- and gender-matched control subjects were recruited (males 336 and females 276, age range 12–63 years). Anthropometric and metabolic parameters were taken by standard procedures and biochemical analyses, respectively. Behavior-related information was collected with a questionnaire. The genotypes of the variants were determined by allelic discrimination Taqman assays. Both variants were found to have a significant association with overweight/obesity according to the over-dominant model. The rs4864548 and rs6843722 were observed to escalate the risk of overweight/obesity by 1.611 ( p = 0.004) and 1.657 ( p = 0.002) times, respectively. These variants were also seen to be significantly associated with various other adiposity-related anthropometric parameters ( p < 0.05). However, no association of both variants with metabolic and behavioral parameters was observed ( p > 0.05). Thus, these variants may contribute to increasing the risk of overweight/obesity and related anthropometric traits in Pakistanis.

Genetics of Sleep and Insights into Its Relationship with Obesity

Considerable recent advancements in elucidating the genetic architecture of sleep traits and sleep disorders may provide insight into the relationship between sleep and obesity. Despite the considerable involvement of the circadian clock in sleep and metabolism, few shared genes, including FTO, were implicated in genome-wide association studies (GWASs) of sleep and obesity. Polygenic scores composed of signals from GWASs of sleep traits show largely null associations with obesity, suggesting lead variants are unique to sleep. Modest genome-wide genetic correlations are observed between many sleep traits and obesity and are largest for snoring.Notably, U-shaped positive genetic correlations with body mass index (BMI) exist for both short and long sleep durations. Findings from Mendelian randomization suggest robust causal effects of insomnia on higher BMI and, conversely, of higher BMI on snoring and daytime sleepiness. Bidirectional effects between sleep duration and daytime napping with obesity may also exist. Limited gene-sleep interaction studies suggest that achieving favorable sleep, as part of a healthy lifestyle, may attenuate genetic predisposition to obesity, but whether these improvements produce clinically meaningful reductions in obesity risk remains unclear. Investigations of the genetic link between sleep and obesity for sleep disorders other than insomnia and in populations of non-European ancestry are currently limited. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Actigraphy in sleep research with infants and young children: Current practices and future benefits of standardized reporting

Actigraphy is a cost-efficient method to estimate sleep-wake patterns over long periods in natural settings. However, the lack of methodological standards in actigraphy research complicates the generalization of outcomes. A rapidly growing methodological diversity is visible in the field, which increasingly necessitates the detailed reporting of methodology. We address this problem and evaluate the current state of the art and recent methodological developments in actigraphy reporting with a special focus on infants and young children. Through a systematic literature search on PubMed (keywords: sleep, actigraphy, child *, preschool, children, infant), we identified 126 recent articles (published since 2012), which were classified and evaluated for reporting of actigraphy. Results show that all studies report on the number of days/nights the actigraph was worn. Reporting was good with respect to device model, placement and sleep diary, whereas reporting was worse for epoch length, algorithm, artefact identification, data loss and definition of variables. In the studies with infants only (n = 58), the majority of articles (62.1%) reported a recording of actigraphy that was continuous across 24 hr. Of these, 23 articles (63.9%) analysed the continuous 24-hr data and merely a fifth used actigraphy to quantify daytime sleep. In comparison with an evaluation in 2012, we observed small improvements in reporting of actigraphy methodology. We propose stricter adherence to standards in reporting methodology in order to streamline actigraphy research with infants and young children, to improve comparability and to facilitate big data ventures in the sleep community.

Sleep disruption and duration are associated with variants in genes involved in energy homeostasis in adults with HIV/AIDS

OBJECTIVE

To determine whether selected genes and plasma markers involved in energy homeostasis are associated with sleep disruption or duration in adults with HIV/AIDS.

METHODS

A sample of 289 adults with HIV/AIDS wore a wrist actigraph for 72 h to estimate total sleep time (TST) and wake after sleep onset (WASO). Twenty-three single nucleotide polymorphisms (SNP) spanning 5 energy homeostasis genes (adiponectin [ADIPOQ], ghrelin [GHRL], leptin [LEP], peroxisome proliferator-activated receptor-alpha [PPARA], and -gamma [PPARG]) were genotyped using a custom array. Plasma markers of energy homeostasis (adiponectin, ghrelin, leptin) were measured by commercial multiplex assay.

RESULTS

After adjusting for demographic and clinical characteristics (race/ethnicity, gender, CD4 cell count, waist circumference, medications), both WASO and TST were associated with SNPs in ADIPOQ (rs182052), LEP (rs10244329, rs3828942), PPARA (rs135551, rs4253655), and PPARG (rs709151). Additional SNPs in ADIPOQ were associated with WASO (rs1501299, rs3821799, rs6773957) and TST (rs2241766). TST was also associated with SNPs in GHRL (rs26802), LEP (rs11760956), PPARA (rs135547, rs8138102, rs4253776), and PPARG (rs12490265, rs796313). Many covariate-adjusted associations involved a significant interaction with markers of HIV (viral load, years since diagnosis). Among plasma markers, higher adiponectin was associated with less WASO, higher ghrelin and glucose levels with shorter TST, and higher leptin with longer TST.

CONCLUSIONS

Replication of SNPs in all five genes and three plasma markers of energy homeostasis were associated with objective sleep measures. HIV disease influenced many of the associations. Findings strengthen evidence for associations between energy homeostasis genetics and poor sleep, and provide direction for pharmacological intervention research.

Sex modifies the association between the CLOCK variant rs1801260 and BMI in school-age children

Disruption of circadian rhythms and variations in the FTO gene may interfere with energy homeostasis and play a role in the development of obesity. The current study assessed the association of common polymorphisms in the CLOCK and FTO genes with standardized body mass index scores (BMI z-scores) and their potential modification of the impact of a culinary nutrition and physical activity intervention in school-age children. Anthropometric measurements were collected in 121 children at the baseline and one-year follow-up of a controlled trial of a school-based culinary nutrition and physical activity intervention. Genotypes of the CLOCK polymorphism (rs1801260) and the FTO polymorphism (rs9939609) were obtained from buccal swabs. Linear mixed-effects regression was applied to evaluate the genetic association and adjust for clusters within families and schools. In our participants, obesity affected 6.6% (8/121) of the children at the baseline and 6.4% (7/109) of the children at the follow-up. The associations between the age- and sex-adjusted BMI z-scores and the two polymorphisms did not reach statistically significance. Yet, sex potentially modified the association between rs1801260 and BMI z-scores. In girls, the G allele carriers had a higher BMI z-scores at the baseline and the follow-up. These polymorphisms did not modify the effect of our culinary nutrition and physical activity intervention on BMI z-scores. Sex is a potential modifier for the association between the CLOCK polymorphism, rs1801260, and BMI z-scores in school-age children. Further investigation is warranted to delineate the sex-dependent role of the CLOCK polymorphisms in the development of childhood obesity.

Sleep and obesity among children: A systematic review of multiple sleep dimensions

The objectives were to systematically investigate the multiple dimensions of sleep and their association with overweight or obesity among primary school-aged children. CINHAL, PsycINFO, SPORTDiscus, Medline, Cochrane, Embase, and PubMed databases were searched for papers reporting on an association between children's sleep and weight status. Studies on clinical populations, published in languages other than English, without objectively measured weight status, or where weight status was reported outside the outlined age bracket (5-13 years) were excluded. A total of 34  248 citations were extracted from our systematic search protocol, of which 112 were included for detailed review. Compared with sleep duration, of which 86/103 articles found a significant inverse association between sleep duration and measured weight status, few studies examined other dimensions of sleep, such as quality, efficiency and bed/wake times, and relationship with weight status. Where studies existed, variation in defining and measurement of these dimensions restricted comparison and potentially influenced discrepancies across results. Overall, the findings of this review warrant the need for further research of the outlined dimensions of sleep. Future research would benefit from clarity on definitions across the different dimensions, along with the use of valid and reliable tools.

Interaction of the CMTM7 rs347134 Polymorphism with Dietary Patterns and the Risk of Obesity in Han Chinese Male Children

A genome-wide association study (GWAS) in the Han Chinese population had found that single nucleotide polymorphism (SNP) on the CMTM7 gene rs347134 was significantly associated with Body Mass Index (BMI). In the present study, the association of the rs347134 SNP with obesity and its interaction with dietary patterns (DPs) were explored in Han Chinese children. This cross-sectional study group included 1292 children, in whom obesity-related indicators were evaluated, the rs347134 SNP was genotyped by improved Multiple Ligase Detection Reaction (iMLDR), and the DPs were identified by principal component factor analysis. The GG genotype exhibited higher odds of general overweight/obesity (P = 0.038) and central obesity (P = 0.039) than AA + GA genotypes in boys. Four DPs of boys were identified: healthy balanced (HBDP), nuts and sweets-based (NSDP), animal food-based (AFDP), and wheaten and dairy-based (WDDP). Boys with the GG genotype were significantly more inclined to AFDP (P = 0.028) and had a shorter sleep duration (P = 0.031). Significant interactions were observed; boys with the GG genotype displayed a higher LDL in AFDP (P = 0.031) and higher FBG in NSDP (P = 0.038), respectively. Our findings indicate for the first time that the GG genotype of CMTM7 rs347134 is potentially a novel obesity risk factor for Han Chinese male children and is associated with dietary patterns more or less.