Day type and the relationship between weight status and sleep duration in children and adolescents

Normal Sleep in Children and Adolescence

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

Determinants of Double Burden of Malnutrition Among School Children and Adolescents in Urban Dhaka: A Multi-Level Analyses

Background

Bangladesh faces a double burden of malnutrition, with a rising prevalence of overweight and obesity among children and adolescents parallel to existing undernutrition.

Objective

The current study was designed to assess the determinants of double burden of malnutrition among urban school children and adolescents from Dhaka, Bangladesh.

Methods

A cross-sectional survey was conducted among 2,690 students from 14 schools in Dhaka city from January to June 2018. Anthropometric measurements were taken during school hours, and self-administered questionnaires were sent to the parents. We performed multi-level multiple logistic regression analyses to assess the determinants of underweight, overweight, and obesity.

Findings

The prevalence of overweight (33%) and obesity (23%) was highest among children and adolescents from high tuition schools but the prevalence of underweight (4%) was lowest compared to those from low (underweight 19%, overweight 17%, and obesity 6%) and medium (underweight 18%, overweight 15%, and obesity 6%) tuition schools. Children and adolescents from high-tuition schools had higher odds of being overweight/ obese (AOR: 2.92; 95% CI: 1.90, 4.49). Parental NCDs and overweight were negatively associated with underweight but positively associated with overweight and obesity among children and adolescents. Lack of physical activity inside schools was positively associated (AOR: 1.26; 95% CI: 1.02, 1.55) with overweight and obesity among school children and adolescents.

Conclusion

Our results point to opportunities in and outside schools to address the rising prevalence of underweight, overweight, and obesity among urban school children and adolescents.

Association of sleep duration and sleep quality with overweight/obesity among adolescents of Bangladesh: a multilevel analysis

Background

Sleep deprivation is widely recognized as a potential contributor to childhood obesity. However, few studies have addressed this issue in low-income settings. The aim of this study was to determine the association of both sleep duration and sleep quality with overweight/obesity among adolescents of Bangladesh.

Methods

A cross-sectional study was conducted in four randomly selected schools in Gazipur, Bangladesh, from May to August 2019. Using a self-administered semi-structured questionnaire, data on sleep duration and sleep quality were collected from 1,044 adolescents between 13 and 17 years of age. The body mass indices of the study participants were evaluated using their objectively-assessed anthropometric measurements (weight and height). Multilevel logistic regression was used for data analysis.

Results

The prevalence of underweight, overweight and obesity in adolescents in this study were 14.9, 18 and 7.1%, respectively. More than 15% of the students reported sleep disturbance and poor sleep quality. After adjusting for confounders, reduced (<7 h/day) total sleep duration (OR=1.73, 95% CI=1.21-2.47), weekend sleep duration (OR=1.46, 95% CI=1.00-2.12), and night sleep duration (OR=1.55, 95% CI=1.06-2.28) were found to be significantly associated with overweight or obesity in Bangladeshi adolescents. Similarly, significant positive associations were evident between short duration of total sleep (OR=0.33, 95% CI=0.20-0.54), weekday sleep (OR=0.55, 95% CI=0.35-0.84), weekend sleep (OR=0.53, 95% CI=0.31-0.89), and night sleep (OR=0.56, 95% CI=0.36-0.87), and underweight in study participants. Adolescents with short sleep duration were found less likely to be underweight and more likely to be overweight/obese.

Conclusions

Study findings denoted short sleep duration to be associated with overweight/obesity and underweight among adolescents of Bangladesh. Adequate sleep may therefore serve as an effective obesity prevention strategy in the growing stages.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12774-0.

Normal Sleep in Children and Adolescence

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

Time spent watching television impacts on body mass index in youth with obesity, but only in those with shortest sleep duration

AIM

To determine the interplay between sleep and sedentary behaviours on body mass index (BMI) in children with obesity.

METHODS

Cross-sectional study of 343 children with obesity aged 4-17 years, from a tertiary care weight management clinic in Melbourne, Victoria, Australia. Multifaceted data relating to activity and sleep from child and parent questionnaires analysed with anthropometric data collected during routine clinical care. Associations between sleep duration and activity measures were examined via regression models with adjustment for potential confounders.

RESULTS

Higher BMI was associated with more hours spent watching television (P = 0.04), as well as less reported enjoyment of physical activity (P = 0.005) and less time spent in organised sport activity (P = 0.005). Higher BMI was also associated with higher levels of obstructive sleep apnoea (P = 0.002). Less time in bed was associated with higher levels of BMI (P = 0.03) but analysis by sex revealed this association to only hold for males. In the whole group, a significant television and sleep interaction was seen, such that increasing television watching was associated with higher BMI, but only in those with shortest sleep duration.

CONCLUSIONS

Both poor sleep and increasing screen time (including television viewing, smart-phone use, internet use or video-gaming) appear to impact BMI in children with obesity, with a particular detrimental effect of television viewing in those who sleep less. Efforts to improve sleep time and quality in children may minimise negative effects of screen time on increasing BMI and should be included in public health strategies to combat obesity in childhood.

The relationship between obesity and sleep timing behavior, television exposure, and dinnertime among elementary school-age children

STUDY OBJECTIVES

The daily lifestyle behaviors of children have been shown to be associated with obesity. There are limited studies on the association of sleep timing behavior and body mass index (BMI), specifically in elementary school-age children. This study aimed to investigate the relationship between obesity and sleep timing patterns, television exposure time, and dinnertime among elementary school-age children.

METHODS

Children (n = 169) aged 6 to 10 years who were residents of Alabama were recruited for this study. The questionnaires were used to determine the bedtime, wake-up time, television exposure time, and dinnertime of the participants. The participants were categorized into four groups depending on the bedtime and wake-up time behavior habits: early bed/early wake-up (EE); early bed/late wake-up (EL); late bed/early wake-up (LE); and late bed/late wake-up (LL) time. The BMI z-score, television exposure time, and dinnertime of these groups were compared.

RESULTS

The LL group had a significantly higher BMI z-score compared to the EE group. The higher BMI z-score in the LL group may be associated with late bedtime and not late wake-up time. Approximately 71% of children with late bedtime (8:48 pm), 75% of children who watch television for more than 1 hour, and 54% of children who have dinner after 7:00 pm have obesity.

CONCLUSIONS

Daily behavior habits such as late bedtime, increased television exposure, and late dinnertime are associated with obesity.

Sleep duration and risk of obesity among a sample of Victorian school children

Background

Insufficient sleep is potentially an important modifiable risk factor for obesity and poor physical activity and sedentary behaviours among children. However, inconsistencies across studies highlight the need for more objective measures. This paper examines the relationship between sleep duration and objectively measured physical activity, sedentary time and weight status, among a sample of Victorian Primary School children.

Methods

A sub-sample of 298 grades four (n = 157) and six (n = 132) Victorian primary school children (aged 9.2-13.2 years) with complete accelerometry and anthropometry data, from 39 schools, were taken from a pilot study of a larger state based cluster randomized control trial in 2013. Data comprised: researcher measured height and weight; accelerometry derived physical activity and sedentary time; and self-reported sleep duration and hypothesised confounding factors (e.g. age, gender and environmental factors).

Results

Compared with sufficient sleepers (67 %), those with insufficient sleep (<10 hrs/day) were significantly more likely to be overweight (OR 1.97, 95 % CI:1.11-3.48) or obese (OR 2.43, 95 % CI:1.26-4.71). No association between sleep and objectively measured physical activity levels or sedentary time was found.

Conclusion

The strong positive relationship between weight status and sleep deprivation merits further research though PA and sedentary time do not seem to be involved in the relationship. Strategies to improve sleep duration may help obesity prevention initiatives in the future.

Sleep Patterns in Adults with a Diagnosis of High-Functioning Autism Spectrum Disorder

STUDY OBJECTIVES

To examine sleep patterns and sleep problems and their relationship with daytime functioning in adults with a diagnosis of an autism spectrum disorder and no comorbid intellectual disability (high-functioning autism spectrum disorder [HFASD]) compared to neurotypical (NT) adults.

DESIGN

Cross-sectional.

SETTING

Home-based study.

PARTICIPANTS

36 adults with HFASD and 36 age-, intelligence quotient- and sex-matched NT adults.

MEASUREMENTS

Participants completed an online questionnaire battery including the Pittsburgh Sleep Quality Index (PSQI), a 14-d sleep wake diary and 14-d actigraphy data collection.

RESULTS

Adults with HFASD had significantly more general sleep disturbances and higher scores on the PSQI, longer sleep onset latencies (actigraphy), and poorer sleep efficiency (diary) and these results remained significant after accounting for the False Discovery Rate. Those adults with HFASD who did not have a comorbid diagnosis of anxiety/depression had significantly shorter total sleep time (diary and actigraphy) compared to NT adults. Compared to NT adults, the HFASD group self-reported significantly poorer refreshment scores upon waking in the morning and higher scores on the daytime dysfunction due to sleepiness subscale of the PSQI.

CONCLUSIONS

These findings support the notion that problems related to sleep, in particular insomnia, continue into adulthood in individuals with high-functioning autism spectrum disorder.

The complexities of defining optimal sleep: empirical and theoretical considerations with a special emphasis on children

The main aim of this paper is to consider relevant theoretical and empirical factors defining optimal sleep, and assess the relative importance of each in developing a working definition for, or guidelines about, optimal sleep, particularly in children. We consider whether optimal sleep is an issue of sleep quantity or of sleep quality. Sleep quantity is discussed in terms of duration, timing, variability and dose-response relationships. Sleep quality is explored in relation to continuity, sleepiness, sleep architecture and daytime behaviour. Potential limitations of sleep research in children are discussed, specifically the loss of research precision inherent in sleep deprivation protocols involving children. We discuss which outcomes are the most important to measure. We consider the notion that insufficient sleep may be a totally subjective finding, is impacted by the age of the reporter, driven by socio-cultural patterns and sleep-wake habits, and that, in some individuals, the driver for insufficient sleep can be viewed in terms of a cost-benefit relationship, curtailing sleep in order to perform better while awake. We conclude that defining optimal sleep is complex. The only method of capturing this elusive concept may be by somnotypology, taking into account duration, quality, age, gender, race, culture, the task at hand, and an individual's position in both sleep-alert and morningness-eveningness continuums. At the experimental level, a unified approach by researchers to establish standardized protocols to evaluate optimal sleep across paediatric age groups is required.

Sleep timing moderates the concurrent sleep duration-body mass index association in low-income preschool-age children

OBJECTIVE

To test the independent main and moderating effects of sleep timing on body mass index (BMI) in low-income preschool-age children (M = 4.11 years, SD = 0.54).

METHODS

Parents reported demographics and children's sleep concurrently, and a subset of children was followed longitudinally. Child height and weight were measured and BMI z score (BMIz) calculated. Regression analysis evaluated main effects of sleep timing (bedtime, weekday-to-weekend schedule shifting, napping) on concurrent BMIz and future rate of change, and their moderating effects on the sleep duration-BMIz association.

RESULTS

Of 366 children (longitudinal subsample = 273), 50% were boys, 57% white, and 37% overweight or obese. Nocturnal sleep duration predicted concurrent BMIz, but not rate of change in BMIz over time. Bedtime was a moderator; the sleep duration-BMIz association was present only among children with bedtimes after 9 pm (β = -0.44; 95% confidence interval -0.69, -0.18). Schedule shifting was a moderator; the association between greater nocturnal sleep duration and lesser rate of future BMIz increase was present only among children with the most consistent sleep schedules (<45-minute delay in weekend bedtime: β = -0.12; 95% confidence interval -0.23, -0.01). Daytime napping did not moderate the nocturnal sleep duration-BMIz association. Covariates (sleep-disordered breathing, soda consumption, home chaos) did not explain these associations.

CONCLUSIONS

Among low-income preschoolers, sleep timing moderated the nocturnal sleep duration-BMIz association. Understanding how sleep timing and sleep duration relate to childhood obesity is important for prevention efforts.

Subjective reports of children's sleep duration: does the question matter? A literature review

Questionnaires are widely used to determine children's sleep duration. While authors have been encouraged to move on from the question: 'how many hours of sleep do you usually get?', the validity of different reports remains unclear, and there do not appear to be any evidence-based recommendations for how to best enquire about children's sleep. Our study aims to determine the validity of subjective reports of children's sleep duration and if elements of phrasing influence the accuracy of reports. A systematic literature review was conducted to identify studies that report the subjective sleep duration of children ages five to 18years, inclusive. A thematic analysis was used to identify 'elements' of phrasing that may influence the accuracy of reports, and a descriptive analysis was conducted to determine the validity of subjective reports. Our review identified five elements of phrasing that may affect the accuracy of reports. These include, specifying sleep parameters that define sleep duration, the recall period, the day type, the method of data collection, and the respondent. The validity of subjective reports varied across studies and in accordance with identified elements of phrasing. Future studies that assess subjective reports of children's sleep should define sleep duration, the recall period, the days constituting schooldays and nonschooldays, the method of data collection, and the respondent of the questionnaire.

Screen time is more strongly associated than physical activity with overweight and obesity in 9- to 16-year-old Australians

BACKGROUND

Both reduced moderate-to-vigorous physical activity (MVPA) and increased screen time have been implicated in the aetiology of childhood overweight/obesity. This study aimed to determine which behaviour had the stronger association with overweight/obesity.

METHOD

2200 randomly selected 9- to 16-year-old Australians provided four 24-h use-of-time recalls. Participants were classified into weight status categories and as high or low physical active, and high or low screen time according to Australian guidelines (≥60 min MVPA; ≤120 min recreational screen time daily). Multivariate logistic regression was used to calculate the odds ratios (OR) for overweight/obesity for each screen time and MVPA category.

RESULTS

Increased likelihood of overweight or obese was often associated with high screen time (ORs, 2.13-2.55 for boys and 1.47-1.72 for girls), but only sometimes and less strongly associated with low MVPA (ORs, 0.49-2.55 for boys and 1.06-1.47 for girls). Analyses conducted for combined screen time and MVPA categories showed screen time to be a stronger indicator of weight status than physical activity, especially in boys.

CONCLUSION

Overweight and obesity were more strongly associated with screen time than physical activity. Screen time may be an important target for interventions aimed at reducing childhood overweight and obesity.

Sleep duration or bedtime? Exploring the relationship between sleep habits and weight status and activity patterns

STUDY OBJECTIVES

To assess the effects of early and late bedtimes and wake up times on use of time and weight status in Australian school-aged children.

DESIGN

Observational cross-sectional study involving use of time interviews and pedometers.

SETTING

Free-living Australian adolescents.

PARTICIPANTS

2200 9- to 16-year-olds from all states of Australia

INTERVENTIONS

NA.

MEASUREMENTS AND RESULTS

Bedtimes and wake times were adjusted for age and sex and classified as early or late using median splits. Adolescents were allocated into 4 sleep-wake pattern groups: Early-bed/Early-rise; Early-bed/Late-rise; Late-bed/Early-rise; Late-bed/Late-rise. The groups were compared for use of time (screen time, physical activity, and study-related time), sociodemographic characteristics, and weight status. Adolescents in the Late-bed/Late-rise category experienced 48 min/d more screen time and 27 min less moderate-to-vigorous physical activity (MVPA) (P<0.0001) than adolescents in the Early-bed/Early-rise category, in spite of similar sleep durations. Late-bed/Late-rise adolescents had a higher BMI z-score (0.66 vs. 0.45, P=0.0015). Late-bed/Late-rise adolescents were 1.47 times more likely to be overweight or obese than Early-bed/Early-rise adolescents, 2.16 times more likely to be obese, 1.77 times more likely to have low MVPA, and 2.92 times more likely to have high screen time. Late-bed/Late-rise adolescents were more likely to come from poorer households, to live in major cities, and have fewer siblings.

CONCLUSIONS

Late bedtimes and late wake up times are associated with an unfavorable activity and weight status profile, independent of age, sex, household income, geographical remoteness, and sleep duration.

Sleep and obesity in children and adolescents

The purpose of this review is to provide a comprehensive update of epidemiologic studies that have assessed the association between sleep and obesity risk. Data suggest that short sleep is associated with an increased risk for being or becoming overweight/obese or having increased body fat. Late bedtimes are also a risk factor for overweight/obesity. Findings also suggest that changes in eating pathways may lead to increased body fat. Future experimental studies are needed to enhance our understanding of the underlying mechanisms through which sleep may play a role in the development and maintenance of childhood obesity.

Normative data on the sleep habits of Australian children and adolescents

STUDY OBJECTIVE

To provide normative sleep data on 9-18 year old Australians.

DESIGN

Cohort study.

SETTING

Participants' homes.

PARTICIPANTS

4032 Australians aged 9-18 years.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Participants completed a 48h use of time recall, comprising sleep data for one complete night. Sleep duration, bedtime and wake time were compared across age groups, between genders, and between school and non-school days using ANOVA. Sleep duration declined with age (P < 0.0001) at the rate of 12 min/night per year of age on school days, and 4 min on non-school days. Girls slept slightly longer than boys (5 min/night; P = 0.03). Non-school day sleep was 16 min longer than school day sleep (P < 0.0001), with the difference increasing with age. Bedtimes got later with age (P < 0.0001), however there were no differences in bedtimes between boys and girls. Bedtimes occurred 34 min later on non-school days (P < 0.0001). Wake times were very similar across age groups on school days, but increased at the rate of 10 min/year of age on non-school days. Wake times were similar for boys and girls, and occurred on average 82 min later on non-school days (P < 0.0001). Overall, 17% of school days and 20% of non-school days failed to meet the American Centers for Disease Control and Prevention sleep duration guidelines.

CONCLUSIONS

Normative sleep data will provide a valuable yardstick for health and education professionals when dealing with sleep-related issues.