Sleep Duration and School Readiness of Chinese Preschool Children

The time sensitive and dose-responsive association between parental corporal punishment and sleep disturbances in preschoolers: A prospective cohort study

BACKGROUND

To examine whether parental corporal punishment is associated with increased risk of concurrent and later sleep disturbances among preschoolers, and whether the association is time-sensitive or dose-responsive.

METHODS

This 3-year prospective cohort study used data from the Shanghai Children's Health, Education and Lifestyle Evaluation, Preschool(SCHEDULE-P). Participants were newly enrolled preschoolers in November 2016(wave 1) and followed up in April 2018(wave 2) and April 2019(wave 3). Parents reported the children's corporal punishment experiences and sleep disturbances at each wave survey. Children's risk of sleep disturbances in relation to corporal punishment was examined using logistic regression, adjusting for children's age, gender, emotional/behavioral problems, family annual income, and maternal educational level.

RESULTS

The participants of 19,668 children included 9436(47.98 %) females, with a mean age of 3.73(SD = 0.29) years at wave 1. Exposure to corporal punishment was associated with increased odds of concurrent sleep disturbances at wave 1, 2, and 3 (aOR,1.57; 95 % CI, 1.40-1.75; P < .001; aOR,1.60; 95 % CI, 1.43-1.80; P < .001; aOR,1.74; 95 % CI, 1.54-1.95; P < .001), respectively. Exposure to corporal punishment at any wave of preschool was associated with increased odds of sleep disturbances at wave 3, and the risks were greater for proximal and accumulative corporal punishment exposure.

CONCLUSION

There is a time-sensitive and dose-responsive association between corporal punishment and sleep disturbance among preschoolers, with greater risk of sleep disturbances for proximal and accumulative exposure of corporal punishment. Promoting positive parenting strategies and avoiding corporal punishment can be a promising strategy to prevent and intervene sleep disturbances in preschoolers.

Evaluation of the association between excessive screen use, sleep patterns and behavioral and cognitive aspects in preschool population. A systematic review

In this review, we analyzed the possible relationship between the excessive use of screens and sleep patterns, and how this may affect certain behavioral and cognitive factors in preschool children. The selection, extraction and synthesis of the data were conducted according to PRISMA guidelines. The search was carried out in the electronic databases Medline (PubMed), PsycINFO (American Psychological Association), Scopus and Web of Science (WOS). Of the 597 articles initially identified, 13 met the inclusion criteria. The risk of bias of the articles selected was evaluated using a specific scale created for this purpose. The results found indicate that excessive use of screens is associated with a negative impact on the duration and quality of sleep-in preschoolers, and this worsening of sleep in infancy is related with a greater probability of the appearance of internalizing and externalizing behavioral problems and certain cognitive problems. The results also suggest that sleep could play a mediating or moderating role as a bioregulatory system that attenuates or increases the onset of behavioral and cognitive difficulties in those children most exposed to digital devices.

Early sleep duration trajectories and children's cognitive development: a prospective cohort study

We aimed to investigate the association between sleep duration trajectories and cognitive performance in preschool-aged Chinese children. We included 2131 children from the Ma'anshan birth cohort (MABC) study. Sleep duration trajectories from 6 to 48 months of age were determined using the group-based trajectory modeling (GBTM). Children's intellectual development was assessed using the Wechsler Preschool and Primary Scale of Intelligence. Compared to those with a medium total sleep duration trajectory, children with a short total sleep duration trajectory had poorer cognitive performance on the Visual Spatial Index (VSI) (β = -3.65; 95% CI = -6.77 to -0.53), which was associated with an increased risk of a low full-scale intelligence quotient (FSIQ) (OR = 1.60; 95% CI = 1.02 to 2.51). The short total sleep duration trajectory was associated with a low VSI compared with both the medium total sleep duration trajectory and the long total sleep duration trajectory. Compared to children with normal nighttime sleep duration and normal daytime sleep duration trajectories, children with short nighttime sleep and long daytime sleep duration trajectories, normal nighttime sleep and long daytime sleep duration trajectories, and short nighttime sleep and normal daytime sleep duration trajectories all had lower cognitive performance. The restricted cubic spline (RCS) also showed that children with and appropriate total sleep duration, an adequate nighttime sleep duration, and a moderate daytime sleep duration had higher FSIQ.

CONCLUSIONS

The results of this study emphasize that a medium total sleep duration, adequate sleep at nighttime, and appropriate sleep in the daytime appear to be more beneficial for children's cognitive development.

WHAT IS KNOWN

• Sleep duration in infancy is strongly associated with neurocognitive development.

WHAT IS NEW

• Medium and long total sleep duration trajectories are beneficial for children's cognitive performance compared to the short total sleep duration trajectory. • A medium total sleep duration, adequate sleep at nighttime and appropriate sleep in the daytime appear to be more beneficial for children's cognitive development.

Is the association between sleep and socio-emotional development mediated by weight in toddlers aged 12 to 36 months?

Introduction

Childhood is an important stage for socio-emotional development. Understanding the associations of lifestyle habits with the healthy development of social and emotional skills is crucial for better interventions early in life. This study aims to analyze the association between sleep and socio-emotional development in toddlers aged 12 to 36 months and examine whether weight mediated these associations.

Methods

This study is part of a cluster randomized controlled trial developed in Portuguese childcare centers. A sample of 344 children (176 females) enrolled in the study. Participants' anthropometrics were measured while at childcare centers using standardized procedures. Body mass index (BMI) was computed as the body weight/height2 (kg/m2) ratio. Sleep quality was collected with the Tayside Children's Sleep Questionnaire, a 10-item scale that evaluates the child's ability to initiate and maintain sleep. Two additional questions regarding sleep duration were added. Parental questionnaires assessed the child's sex and date of birth, socioeconomic status, and total energy intake (TEI). Motor (fine and gross) was assessed using Bayley-III scales and socio-emotional (SE) by the Greenspan Social-Emotional Growth Chart questionnaire. Linear regression models were used to examine the associations between sleep (duration and quality) and SE with adjustments for sex, age, BMI, mothers' education, motor development, and TEI. Mediation analysis was conducted using path analysis.

Results

SE development was significantly associated with nighttime sleep duration even when adjusted for confounders (β = 0.223; 95% CI: 0.001, 0.004 and β = 0.168; 0.0003, 0.003; respectively). Sleep quality was not significantly associated with SE development, and the weight did not explain the associations between sleep and SE development.

Conclusion

This study supports that sleep duration is directly associated with SE development in toddlers. From a public health perspective, sleep duration should be prioritized in intervention programs to improve socio-emotional development early in life.

Associations between sleep trajectories up to 54 months and cognitive school readiness in 4 year old preschool children

Purpose

This study explores the association between the duration and variation of infant sleep trajectories and subsequent cognitive school readiness at 48–50 months.

Methods

Participants were 288 multi-ethnic children, within the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort. Caregiver-reported total, night and day sleep durations were obtained at 3, 6, 9, 12, 18, 24 using the Brief Infant Sleep Questionnaire and 54 months using the Child Sleep Habits Questionnaire. Total, night and day sleep trajectories with varying durations (short, moderate, or long) and variability (consistent or variable; defined by standard errors) were identified. The cognitive school readiness test battery was administered when the children were between 48 and 50 months old. Both unadjusted adjusted analysis of variance models and adjusted analysis of covariance models (for confounders) were performed to assess associations between sleep trajectories and individual school readiness tests in the domains of language, numeracy, general cognition and memory.

Results

In the unadjusted models, children with short variable total sleep trajectories had poorer performance on language tests compared to those with longer and more consistent trajectories. In both unadjusted and adjusted models, children with short variable night sleep trajectories had poorer numeracy knowledge compared to their counterparts with long consistent night sleep trajectories. There were no equivalent associations between sleep trajectories and school readiness performance for tests in the general cognition or memory domains. There were no significant findings for day sleep trajectories.

Conclusion

Findings suggest that individual differences in longitudinal sleep duration patterns from as early as 3 months of age may be associated with language and numeracy aspects of school readiness at 48–50 months of age. This is important, as early school readiness, particularly the domains of language and mathematics, is a key predictor of subsequent academic achievement.

Secular trends of sleep-wake patterns in Hong Kong preschoolers

OBJECTIVE

To evaluate the secular trends of sleep-wake patterns of Hong Kong preschool children.

METHODS

Kindergartens from the four geographical regions of Hong Kong were randomly invited to take part in a sleep survey in 2012 and again in 2018. The parent-completed questionnaire provided information on socioeconomic status (SES), children's, and parental sleep-wake patterns. Secular trends and risk factors associated with short sleep duration in preschoolers were explored.

RESULTS

A sample of 5048 preschool children was included in the secular comparison, with 2306 and 2742 from the 2012 and 2018 surveys, respectively. A higher percentage of children in 2018 (41.1% vs 26.7%, p < 0.001) did not achieve the recommended sleep duration. During the survey years, sleep duration decreased by 13 ([95%CI: 18.5 to -8.1]) and 18 min ([95%CI: 23.6 to -12.2]) on weekdays and weekends, respectively. The overall trend of nap decrease was not significant. Sleep onset latency significantly increased on both weekdays (6 min [95%CI: 3.5 to 8.5]) and weekends (7 min [95%CI: 4.7 to 9.9]). Children's sleep duration was positively correlated with parental sleep duration with a correlation coefficient ranging from 0.16 to 0.27 (p < 0.001).

CONCLUSIONS

A significant proportion of Hong Kong preschool children did not achieve the recommended amount of sleep. A downward secular trend in sleep duration was observed during the survey period. Public health measures to improve sleep duration in preschool children should be a high priority.

Sleep Patterns and School Readiness of Pre-Kindergarteners from Racially and Ethnically Diverse, Low-Income Backgrounds

OBJECTIVE

To explore patterns in parent-reported child sleep health and to investigate connections between such patterns and school readiness for newly enrolled prekindergarten (PreK) attendees from racially and ethnically diverse, low-income backgrounds.

STUDY DESIGN

In a secondary analysis from a larger multiple-cohort longitudinal observational study of prekindergartners in low-income families, parental reports of sleep health for 351 children (mean age, 52.8 ± 3.5 months) during the first month of PreK were analyzed. Children also had completed direct assessments measuring language, literacy, mathematics, and executive functioning, and teachers rated children's social-emotional-behavioral competencies and approaches to learning at PreK entry. We performed latent class analyses to identify patterns in sleep health and used regression models to examine concurrent associations between child sleep health patterns and school readiness competencies across 6 domains: language, literacy, mathematics, executive functioning, social-emotional-behavioral, and approaches to learning.

RESULTS

Two classes emerged reflecting more and less desirable patterns of sleep health. Children classified in the earlier, longer, consistent sleep health class (87% of children) experienced earlier bedtimes, longer night-time sleep durations, more consistent sleep routines, less caffeine consumption ≤3 hours before bedtime, and scored higher on a direct assessment of expressive vocabulary and on teacher-reported measures of social-emotional-behavioral competencies and learning approaches than their peers in the later, shorter, inconsistent sleep health class (13% of children).

CONCLUSIONS

Consistent sleep routines and more optimal sleep health may serve as a protective mechanism for the language development, social-emotional-behavioral regulation, and approaches to learning of PreK from racially and ethnically diverse, low-income backgrounds. Clinician-parent discussions regarding optimal sleep health may provide key opportunities for targeted education that promotes school readiness skill development.

The associations of chronotype and social jetlag with prosocial behavior problems among Chinese adolescents

Potential relevance between the circadian rhythm and behavioral health has got raising attention in recent years. This study aimed to examine chronotype, social jetlag and their associations with prosocial behavior problems among Chinese adolescents. A total of 4,666 middle school students aged 12-18 years were enrolled in study. Sleep characteristics were collected by the modified Chinese version of Adolescent Sleep Hygiene Scale (M-ASHS); MSFsc and mid-sleep point were calculated to determine chronotypes and social jetlag. Prosocial behavior problems were assessed by the Strength and Difficult Questionnaire (SDQ). Multivariate logistic regression was applied to analyze the relationships between chronotype and social jetlag with prosocial behavior problems. Evening chronotype was associated with higher risk of prosocial behavior problems, whether among male (OR = 1.82, 95%CI:1.27-2.61, P = .001) or female adolescents (OR = 1.83, 95%CI:1.15-2.91, P = .011). Female adolescents with social jetlag of 1-2 hours had 1.60 times the risk of prosocial behavior problems than their peers whose social jetlag was <1 h (P = .028); social jetlag ≥ 2 h was positively associated with prosocial behavior problems in both male and female adolescents (OR = 1.79 and 2.45, respectively, both P < .05). Further, the combination of intermediate chronotype and social jetlag ≥ 2 h was correlated with prosocial behavior problems only in female adolescents (OR = 3.24, 95%CI = 1.40-9.21, P = .004). Evening chronotype and higher social jetlag were risk factors for prosocial behavior problems in adolescents, especially for the female. For the promotion of prosocial behavior in adolescents, the importance of circadian rhythm should be addressed.

A Longitudinal Approach to the Relationships Among Sleep, Behavioral Adjustment, and Maternal Depression in Preschoolers

This study aimed to investigate the longitudinal associations between children’s sleep duration (SD) and problems (SPs), behavioral adjustment [externalizing behaviors (EB) and internalizing behaviors (IB)], and maternal depressive symptoms (MDS) in preschoolers over a period of 3 years (4–6 years of age). For this purpose, latent growth modeling (LGM) was conducted using 2012(W₅) to 2014(W₇) data from the National Panel Study on Korean Children (PSKC), while controlling for family contextual factors (i.e., responsive parenting, developmental stimulations, and marital conflict) and child temperament (children’s negative emotionality). First, children who slept longer at four were concurrently associated with lower levels of EB, while more SPs were associated with higher levels of EB and IB, concurrently. Second, greater decreases in SPs were associated with greater decline in EB and IB. Higher levels of MDS at four were associated with higher levels of child EB, IB, and SPs, concurrently. However, no longitudinal associations were found between the rates of change in MDS and children’s sleep and adjustment (EB and IB). Finally, the magnitude of the associations among the variables was greater overall in the SPs models than in the SD models. These findings suggest that addressing sleep problems, rather than sleep duration, seem to be more important in predicting and preventing young children’s adjustment problems and also that more attention should be paid to MDS during preschool years as much as during the postpartum period for better child adjustment outcomes.

The association between child maltreatment and sleep disturbances among preschoolers

BACKGROUND

Child maltreatment (CM) can result in lifelong detrimental consequences, but its association with sleep disturbances in young children remains unclear.

OBJECTIVE

This study aimed to investigate the association of CM with sleep disturbances and short sleep duration among Chinese preschoolers.

PARTICIPANTS AND SETTING

Data were from a representative sample of 17,023 children (6.17 ± 0.29 years old, 51.96% boys) at their graduation year of preschool in September 2019, as a subset of the Shanghai Children's Health, Education and Lifestyle Evaluation-Preschool (SCHEDULE-P) study.

METHODS

Parents reported children's CM of different types and the Children's Sleep Habits Questionnaire (CSHQ). Logistic regression was used to evaluate the risk of sleep disturbances and short sleep duration linked to CM.

RESULTS

Of the children, 12,583(73.92%) demonstrated sleep disturbances (CSHQ total score > 41) and 3017(17.72%) demonstrated short sleep duration (<9 h/night). After adjusting covariates, physical abuse (aOR = 1.16, 95%CI = 1.05-1.28) and emotional abuse (aOR = 1.50, 95% CI = 1.39-1.62) were associated with global sleep disturbances. Physical abuse (aOR = 1.16, 95% CI = 1.06-1.28), physical neglect (aOR = 1.29, 95%CI = 1.12-1.49), and emotional abuse (aOR = 1.19, 95% CI = 1.09-1.30) were associated with short sleep duration. Sexual abuse was not significantly associated with global sleep disturbances or short sleep duration. A cumulative association was noted that more CM types were associated with increased global sleep disturbances and short sleep duration.

CONCLUSIONS

CM is associated with sleep disturbances and short sleep duration in young children. This highlights the efforts to prevent and reduce CM in favor of optimal sleep and whole health in young children.

Sleep Duration, Bedtime Consistency, and School Readiness: Findings from the 2016 to 2018 National Survey of Children's Health

OBJECTIVE

The focus of this study is to assess the link between sleep duration, bedtime consistency, and school readiness among a nationally representative sample of preschool-age children in the United States.

METHODS

A sample of 15,402 preschool-age children (3 to 5 years old) from the 3 most recent cohorts (2016-2018) of the National Survey of Children's Health was used. Information about sleep duration, bedtime consistency, and school readiness was obtained from surveys administered to primary caregivers. Four distinct domains of school readiness were examined: early learning skills, self-regulation, social-emotional development, and physical health and motor development.

RESULTS

The findings reveal that children who obtain 7 or fewer hours of sleep per night exhibit significant reductions in school readiness both within and across all 4 domains. Similar but more modest patterns emerge among children with inconsistent bedtimes.

CONCLUSION

Given the potential implications of young children's sleep for school readiness, pediatricians should be prepared and trained to effectively counsel parents about children's sleep patterns during routine well-child visits. Future research should examine whether improvements in sleep hygiene education for parents, behavioral sleep interventions, and/or later school start times once children enter preschool might enhance school readiness by improving children's health and well-being as they enter school.

Screen time use impacts low-income preschool children's sleep quality, tiredness, and ability to fall asleep

BACKGROUND

Sleep is increasingly recognized as a vital part of health. Screen time has been linked to sleep quality in children. The purpose of this study was to analyze associations between screen time and sleep characteristics among low-income preschoolers.

METHODS

A total of 1,700 preschool-aged children participated in this study at 50 federally and state-funded preschool centers in Michigan. Baseline measurement for an ongoing longitudinal intervention trial was obtained for cross-sectional use. At baseline, parents reported the number of hours their child spent engaging in screen time on a typical week day and weekend. An aggregate measure of total screen time was created. Parents reported on the quality of their child's sleep, how often they were tired during the day, and whether they had difficulty falling asleep. A mixed model linear regression was created to analyze data.

RESULTS

Controlling for child's age, race, and parental income, children who engaged in more screen time were significantly more likely to have more trouble falling or staying asleep, be tired during the day, and had worse quality of sleep (P values = .004, .006 and .001, respectively). Spearman correlations of screen time, sleep variables and demographics show parents of Black children reported significantly higher weekly screen time than parents of non-Black children (r = 0.23, P < .001) and that tiredness was associated with Black race (r = 0.15, P < .001), Hispanic/Latino ethnicity (r = -0.14, P < .001), and parental education (r = 0.06, P = .016).

CONCLUSION

This report confirms prior associations between screen time and sleep reported in other pediatric populations. Further research is needed to confirm these results in other populations using more rigorous measures of screen time, sleep, and physical activity, as well as longitudinal assessments. Despite these limitations, findings suggest that interventions to help parents limit children's screen time and impact their sleep health merit investigation.

Linking cohort-based data with electronic health records: a proof-of-concept methodological study in Hong Kong

OBJECTIVES

Data linkage of cohort-based data and electronic health records (EHRs) has been practised in many countries, but in Hong Kong there is still a lack of such research. To expand the use of multisource data, we aimed to identify a feasible way of linking two cohorts with EHRs in Hong Kong.

METHODS

Participants in the 'Children of 1997' birth cohort and the Chinese Early Development Instrument (CEDI) cohort were separated into several batches. The Hong Kong Identity Card Numbers (HKIDs) of each batch were then uploaded to the Hong Kong Clinical Data Analysis and Reporting System (CDARS) to retrieve EHRs. Within the same batch, each participant has a unique combination of date of birth and sex which can then be used for exact matching, as no HKID will be returned from CDARS. Raw data collected for the two cohorts were checked for the mismatched cases. After the matching, we conducted a simple descriptive analysis of attention deficit hyperactivity disorder (ADHD) information collected in the CEDI cohort via the Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour Scale (SWAN) and EHRs.

RESULTS

In total, 3473 and 910 HKIDs in the birth cohort and CEDI cohort were separated into 44 and 5 batches, respectively, and then submitted to the CDARS, with 100% and 97% being valid HKIDs respectively. The match rates were confirmed to be 100% and 99.75% after checking the cohort data. From our illustration using the ADHD information in the CEDI cohort, 36 (4.47%) individuals had ADHD-Combined score over the clinical cut-off in the SWAN survey, and 68 (8.31%) individuals had ADHD records in EHRs.

CONCLUSIONS

Using date of birth and sex as identifiable variables, we were able to link the cohort data and EHRs with high match rates. This method will assist in the generation of databases for future multidisciplinary research using both cohort data and EHRs.

Association Between Sleep Duration and Intelligence Quotient in 6-Year-Old Children

BACKGROUND

Sufficient sleep during childhood is important for cognitive functions such as learning and successful school performance. This study aimed to investigate the effects of sleep duration on the intelligence quotient (IQ) of 6-year-old children and aimed to analyze whether these effects differed by sex.

METHODS

The IQ of 538 6-year-old Korean participants from the cohort study, "The Environment and Development of Children," was measured during follow-up using the Korean Educational Developmental Institute's Wechsler Intelligence Scale for Children. The total, verbal, and performance IQ scores were evaluated. The relationship between sleep duration and IQ scores after adjusting for maternal age, maternal educational level, maternal occupation, maternal IQ, exposure to secondhand smoking, gestational age, and monthly age and birth season was also assessed.

RESULTS

Longer sleep duration was significantly associated with improved verbal IQ measures (β 0.55; p value 0.030). After stratifying participants by sex, a significant association was observed between sleep duration and total, verbal, and performance IQ scores in boys (total IQ 2.49, p value 0.012; verbal IQ 0.75, p value: 0.037; performance IQ 0.73, p value 0.048), but not in girls.

CONCLUSIONS

The results indicated that only boys show a significant association between IQ scores and sleep duration. These findings support the hypothesis that sleep duration is associated with IQ, in a sex dependent manner. Future studies are needed for a thorough evaluation of the connection between sleep duration and health outcome in young children.

Grandparental care and sleep disturbances in preschool children: a population-based prospective cohort study

OBJECTIVES

Sleep disturbances are common in preschoolers, and profoundly affected by parenting. Grandparents are increasingly involved in childcare and have attracted worldwide attention for their potential impacts on child well-being. However, no studies have explored child sleep health within the context of grandparental care. We aimed to explore the association between grandparents as primary caregivers and children's sleep disturbances.

METHODS

Participants included 20,324 preschoolers from the Shanghai Children's Health, Education and Lifestyle Evaluation-Preschool (SCHEDULE-P) in Shanghai, China. They were initially assessed in November 2016 and were reassessed in April 2018 and April 2019. Children's primary caregivers were collected at each survey. Sleep disturbances were assessed by the Children's Sleep Habits Questionnaire (CSHQ).

RESULTS

At baseline, 84.4% of children had global sleep disturbances (CSHQ total score >41). Compared with parents, random-effects model indicated that grandparents as primary caregivers increased the adjusted odds ratio (OR) for children's global sleep disturbances by 30% (OR [95%CI]: 1.30 [1.21, 1.40]). To the specific domains of CSHQ, two-way repeated-measures ANOVA showed significant "caregiver transition" group × wave interaction in the behavioral sleep disturbances, such as "Bedtime Resistance" (p < 0.001). At each survey, children with grandparents as primary caregivers demonstrated significant higher behavioral sleep disturbances than their counterparts with parental care.

CONCLUSIONS

Grandparental care is associated with increased sleep disturbances, particularly behavioral sleep disturbances, in preschoolers. Future studies should explore the underlying mechanisms and whether sleep programs targeting grandparents can decrease children's sleep disturbances.

Mental Health of Parents and Preschool-Aged Children During the COVID-19 Pandemic: The Mediating Role of Harsh Parenting and Child Sleep Disturbances

In the context of the coronavirus disease-2019 (COVID-19) pandemic, mental health problems of parents and children have become a public issue. Herein, we explored the association between parental well-being index and child mental health problems during the pandemic and the mediating role of harsh parenting and child sleep disturbances. An online survey was conducted among 16,398 parents of children aged 3-6 years (48.1% girls, M_age = 4.69 years, SD_age = 0.75 years) from March 15 to 29, 2020. Child mental health (Strengths and Difficulties Questionnaire, SDQ), sleep problems (Children's Sleep Habits Questionnaire, CSHQ), and parental well-being index (World Health Organization-Five Well-Being Index, WHO-5), and harsh parenting were reported by parents. The results revealed that a higher parental well-being index was associated with lower child mental health problems. Harsh parenting and child sleep problems were significant mediators within the association. This study indicates the association between parental well-being index and child mental health during the pandemic and underlying mechanism, and has important implications for reducing parental and child mental health problems.

The Relationships between Screen Use and Health Indicators among Infants, Toddlers, and Preschoolers: A Meta-Analysis and Systematic Review

Evidence suggests that excessive screen time in early childhood is related to children's physical and mental health. This study aimed to review the relationships between screen media use and several health indicators in infants, toddlers, and preschoolers. A systematic search was conducted by two independent reviewers on PubMed, Web of Science, Embase, and Cochrane Library to identify the eligible studies, with an end date of 13 August 2019. Included studies (published in English) were peer-reviewed and met the determinate population (children aged 0-7 years with screen media exposure and related health outcomes). The AHRQ, NOS, and the Cochrane Handbook were used to evaluate the cross-sectional study, cohort study, and RCT, respectively. A meta-analysis and narrative syntheses were employed separately. Eighty studies (23 studies for meta-analysis) met the inclusion criteria for the systematic review. Strong evidence of the meta-analysis suggested that excessive screen time was associated with overweight/obesity and shorter sleep duration among toddlers and preschoolers. Excessive screen use was associated with various health indicators in physical, behavioral, and psychosocial aspects. Better-quality research on newer media devices, on various kinds of contents in young children, and on dose-response relationships between excessive screen use and health indicators are needed to update recommendations of screen use.

Sleep across early childhood: implications for internalizing and externalizing problems, socioemotional skills, and cognitive and academic abilities in preschool

BACKGROUND

Sleep is thought to be important for behavioral and cognitive development. However, much of the prior research on sleep's role in behavioral/cognitive development has relied upon self-report measures and cross-sectional designs.

METHODS

The current study examined how early childhood sleep, measured actigraphically, was developmentally associated with child functioning at 54 months. Emphasis was on functioning at preschool, a crucial setting for the emergence of psychopathology. Participants included 119 children assessed longitudinally at 30, 36, 42, and 54 months. We examined correlations between child sleep and adjustment across three domains: behavioral adjustment (i.e., internalizing and externalizing problems), socioemotional skills, and academic/cognitive abilities. We further probed consistent associations with growth curve modeling.

RESULTS

Internalizing problems were associated with sleep variability, and cognitive and academic abilities were associated with sleep timing. Growth curve analysis suggested that children with more variable sleep at 30 months had higher teacher-reported internalizing problems in preschool and that children with later sleep timing at 30 months had poorer cognitive and academic skills at 54 months. However, changes in sleep from 30 to 54 months were not associated with any of the domains of adjustment.

CONCLUSIONS

Findings indicate that objectively measured sleep variability and late sleep timing in toddlerhood are associated with higher levels of internalizing problems and poorer academic/cognitive abilities in preschool.

Association between Sleep Disturbances and Emotional/Behavioral Problems in Chinese and Japanese Preschoolers

Objectives: Sleep disturbances are often associated with emotional/behavioral problems in young children, but whether the association differs among Asian countries remains unknown. This study aimed to investigate the association between sleep disturbances and emotional/behavioral problems in Chinese and Japanese preschoolers and to explore potential differences.Methods: Participants were 1,020 Chinese preschoolers from 10 cities and 438 Japanese preschoolers from 1 city aged 4 to 5 years. Parents filled out the Children's Sleep Habits Questionnaire (CSHQ) and the Strengths and Difficulties Questionnaire (SDQ).Results: Chinese children with sleep disturbances (defined as total CSHQ score >41) demonstrated more peer problems than children without, while there was no such difference in Japanese preschoolers. Domains of sleep disturbances associated with emotional/behavioral problems in Chinese children were sleep disordered breathing and daytime sleepiness, yet in Japanese children were sleep anxiety and night wakings. Children with a higher score of sleep anxiety showed more emotional problems in Japan, but fewer conduct problems in China.Conclusions: Sleep disturbances were associated with emotional/behavioral problems in preschoolers with differences between China and Japan, indicating subcultural differences in preschoolers' sleep within Asian countries.Abbreviations: CSHQ: Children's Sleep Habits Questionnaire; SDQ: Strengths and Difficulties Questionnaire; ANCOVA: analysis of covariance; SD: standard deviation; CI: confidence interval.

Fit for School Study protocol: early child growth, health behaviours, nutrition, cardiometabolic risk and developmental determinants of a child's school readiness, a prospective cohort

INTRODUCTION

School readiness is a multidimensional construct that includes cognitive, behavioural and emotional aspects of a child's development. School readiness is strongly associated with a child's future school success and well-being. The Early Development Instrument (EDI) is a reliable and valid teacher-completed tool for assessing school readiness in children at kindergarten age. A substantial knowledge gap exists in understanding how early child growth, health behaviours, nutrition, cardiometabolic risk and development impact school readiness. The primary objective was to determine if growth patterns, measured by body mass index trajectories in healthy children aged 0-5 years, are associated with school readiness at ages 4-6 years (kindergarten age). Secondary objectives were to determine if other health trajectories, including health behaviours, nutrition, cardiometabolic risk and development, are associated with school readiness at ages 4-6 years. This paper presents the Fit for School Study protocol.

METHODS AND ANALYSIS

This is an ongoing prospective cohort study. Parents of children enrolled in the The Applied Health Research Group for Kids (TARGet Kids!) practice-based research network are invited to participate in the Fit for School Study. Child growth, health behaviours, nutrition, cardiometabolic risk and development data are collected annually at health supervision visits and linked to EDI data collected by schools. The primary and secondary analyses will use a two-stage process: (1) latent class growth models will be used to first determine trajectory groups, and (2) generalised linear mixed models will be used to examine the relationship between exposures and EDI results.

ETHICS AND DISSEMINATION

The research ethics boards at The Hospital for Sick Children, Unity Health Toronto and McMaster University approved this study, and research ethics approval was obtained from each school board with a student participating in the study. The findings will be presented locally, nationally and internationally and will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT01869530.

Socio-demographic and maternal predictors of adherence to 24-hour movement guidelines in Singaporean children

PURPOSE

Integrated 24-Hour Movement Guidelines provide specific recommendations on screen viewing (SV), moderate-to-vigorous physical activity (MVPA) and sleep to improve health of children and youth. However, few studies have examined whether these guidelines are met in young children, particularly in Asia. We evaluated adherence to integrated and individual guidelines and its predictors in 5.5-year-old Singaporean children.

METHODS

Growing Up in Singapore towards Healthy Outcomes (GUSTO) is a mother-offspring birth cohort study. At age 5.5 years, child SV was reported by parents. Movement behaviours (MBs) were measured continuously using wrist-worn accelerometers over 7 consecutive days and nights. For accelerometer data including ≥3 days with ≥16 h/day we estimated mean (±SD) daily MVPA, SV and nighttime sleep duration across the week. Adherence to integrated (Canadian/Australian) guidelines was defined as meeting all individual guidelines: ≥60 min of MVPA/day, ≤2 h of screen time/day, and 9-11 h of sleep/night. Socio-demographic and maternal predictors collected at pregnancy enrolment and at 26-28 weeks' gestation were examined by multivariable logistic regression.

RESULTS

Of 864 children followed up age 5.5 years, 547 (63.3%) had both valid ActiGraph and questionnaire data (51.7% boys and 58.3% Chinese ethnicity). Children averaged 101.9 (± 88.7) min/day SV, 67.3 (± 23.7) min/day MVPA and 480.6 (± 57.2) min/night sleep. Few children met integrated guidelines. Specifically, the proportions of children who met none, SV, MVPA, sleep and integrated guidelines were 11.2, 70.2, 59.6, 13.7 and 5.5%, respectively. Multivariable analysis showed that maternal activity and television (TV) viewing were associated with meeting integrated guidelines (insufficiently vs. highly active (OR [95% CI]): 0.11 [0.01, 0.95]; 2-3 vs. ≥ 3 h TV: 3.52 [1.02, 12.22]). Examining higher adherence to individual guidelines, Chinese ethnicity, younger maternal age and lower maternal TV and sleep time were associated with greater SV; male sex, Malay ethnicity, higher birth order and higher maternal activity level were associated with greater MVPA; and older maternal age was associated with adherence to sleep guideline.

CONCLUSIONS

Beyond individual behaviours, consideration of the full spectrum of MBs may be important to improve children's health. However, few Singaporean children adhere to integrated 24-h movement guidelines. Maternal behaviours as early as during pregnancy could be important targets for future interventions aiming to promote these MBs in children.

Beyond Access and Exposure: Implications of Sneaky Media Use for Preschoolers' Sleep Behavior

Greater consumption of and access to screen media are known correlates of unhealthy sleep behavior in preschoolers. What remains unknown, however, is the role a child's media use plays in this association. Parents and guardians of U.S. preschoolers (N = 278, average child age 56 months) provided information about their child's nightly duration of sleep, daily duration of nap, quantity of screen media use, sneaky media use, and the presence of a screen media device in the bedroom. We assessed four media: television, DVD/VCRs, video games, and computer/Internet. Based on rationales of sleep displacement, the forbidden fruit hypothesis, and social cognitive theory, we predicted that increased consumption of and access to media, along with sneaky media use, would predict a shorter duration of nightly sleep and longer duration of daily nap across the four screen media. In correlational analyses, a clear pattern emerged with quantity of media use, screen media in the bedroom, and sneaky media use associated with shorter nightly duration of sleep and longer duration of daily nap. In regression analyses, only weekday evening television viewing and sneaky media use predicted shorter nightly sleep duration; weekend morning and evening DVD use predicted longer naps.

Early sleep deprivation and attention-deficit/hyperactivity disorder

BACKGROUND

This study aims to study prospectively specific sleep patterns and risk of ADHD after adjusting for potential confounders such as obstructive sleep apnoea (OSA) and methylphenidate use.

METHODS

A population-representative sample of 514 Chinese preschool children was recruited when in kindergarten (K3). Parents reported on their socioeconomic status and children's sleep duration. The cohort was reassessed 3 years later when the children were in Grade 3 (P3). Parents reported on children's sleep patterns and ADHD symptoms. Information on OSA diagnosis and methylphenidate use was retrieved from health records.

RESULTS

Among the 514 parent-child dyads (mean [SD] age, 5.52 [0.33] years), 411 were reassessed (80.0% retention; 9.35 [0.33] years) at follow-up. There were no significant baseline differences between follow-up and drop-out groups. A gradient relationship was observed between probable ADHD in P3 and sleep duration in K3. The risk of probable ADHD was 15.5 per 100 for children with <8 h of sleep in K3, whereas it was 1.1 per 100 for children with 11-12 h of sleep in K3. The adjusted risk ratio was 14.19 (p = 0.02).

CONCLUSIONS

Sleep deprivation in early childhood is associated with higher risk of ADHD in middle childhood.

The Intersection of Health and Education to Address School Readiness of All Children

Children who enter kindergarten healthy and ready to learn are more likely to succeed academically. Children at the highest risk for not being ready for school live in poverty and/or with chronic health conditions. High-quality early childhood education (ECE) programs can be used to help kids be ready for school; however, the United States lacks a comprehensive ECE system, with only half of 3- and 4-year-olds being enrolled in preschool, lagging behind 28 high-income countries. As addressing social determinants of health gains prominence in pediatric training and practice, there is increasing interest in addressing ECE disparities. Unfortunately, evidence is lacking for clinically based, early educational interventions. New interventions are being developed asynchronously in pediatrics and education, often without knowledge of the evidence base in the other's literature. In this State-of-the-Art Review, we synthesize the relevant work from the field of education (searchable through the Education Resources Information Center, also known as the "PubMed" of education), combining it with relevant literature in PubMed, to align the fields of pediatrics and education to promote this timely transdisciplinary work. First, we review the education literature to understand the current US achievement gap. Next, we provide an update on the impact of child health on school readiness and explore emerging solutions in education and pediatrics. Finally, we discuss next steps for future transdisciplinary work between the fields of education and pediatrics to improve the health and school readiness of young children.

Correlates of nocturnal sleep duration, nocturnal sleep variability, and nocturnal sleep problems in toddlers: results from the GET UP! Study

OBJECTIVE

To explore the correlates of nocturnal sleep duration, nocturnal sleep variability, and nocturnal sleep problems in a sample of Australian toddlers.

METHODS

Participants were 173 toddlers (average age 19.7 ± 4.1 months) from the GET UP!

STUDY

Nocturnal sleep duration, nocturnal sleep variability, nap(s) and physical activity were measured using 24-h accelerometry (Actigraph GT3X+) over seven consecutive days. Nocturnal sleep problems were assessed using the Tayside Children's Sleep Questionnaire. Screen time was reported by the parents. Logistic regression models were used to examine the associations between potential correlates (ie, age, sex, socio-economic status, weight status, physical activity, screen time, nap(s), bedtimes, and wake-up times) and nocturnal sleep characteristics.

RESULTS

Older children were more likely to have greater sleep variability (OR: 1.97; 95% CI: 1.08-3.61). Less physical activity (OR: 2.38; 95% CI: 1.27-4.45), shorter nap(s) (OR: 2.42, 95% CI: 1.29-4.55), and later wake-up times (OR: 4.42; 95% CI: 2.32-8.42) were associated with higher odds of having longer nocturnal sleep duration. Late bedtimes were associated with shorter nocturnal sleep duration (OR: 0.09; 95% CI: 0.04-0.18) and with greater nocturnal sleep variability (OR: 1.97; 95% CI: 1.06-3.68). None of the potential correlates were associated with nocturnal sleep problems.

CONCLUSION

The present study identifies several correlates of nocturnal sleep duration (total physical activity, nap(s), bedtime, and wake-up time) and nocturnal sleep variability (age and bedtime), whereas no correlates were identified for nocturnal sleep problems. The association between late bedtimes and shorter nocturnal sleep duration and greater nocturnal variability suggests that these may be modifiable targets for future sleep interventions in early childhood.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12616000471482, 11/04/2016, retrospectively registered.

A Community-Based Study of Sleep and Cognitive Development in Infants and Toddlers

STUDY OBJECTIVES

To examine the prevalence and correlates of nighttime awakenings and to explore the association between sleep and cognitive development in a community sample of infants and toddlers.

METHODS

A total of 590 healthy infants (aged 2-11 months) and 512 toddlers (aged 12-30 months) from 8 provinces of China were assessed for their sleep and cognitive development. Data on sleep duration and nighttime awakenings were collected through the Brief Infant Sleep Questionnaire. Cognitive development was assessed by trained pediatricians using the Bayley Scales of Infant Development.

RESULTS

Prevalence of no nighttime awakening, and nighttime awakening(s) for 1×/night, 2×/night, and ≥ 3×/night was 6.8%, 20.2%, 33.2%, and 39.3% in infants, and was 25.8%, 34.6%, 23.8%, and 15.8% in toddlers, respectively. Nighttime awakenings were generally associated with younger age, lower maternal education level, and being currently breastfed. In addition, nighttime awakenings were associated with being boys in toddlers. After controlling for potential confounders, infants with nighttime awakenings for 2×/night were found to have significantly higher Mental Development Index (MDI) score, as compared to those without and those with more frequent nighttime awakenings. However, toddlers with nighttime awakenings for ≥ 3×/night had significantly lower MDI, as compared to those with fewer nighttime awakenings. Total sleep duration was not associated with any developmental indices in both infants and toddlers.

CONCLUSIONS

Frequent nighttime awakenings are associated with poor cognitive functions in toddlers. Meanwhile, a nonlinear association between nighttime awakenings and cognitive performance was found among infants. The findings provide a developmental context for the effect of sleep on cognitive abilities in young children. Further longitudinal studies and interventional studies on the effects of parent-based sleep-focused intervention on cognitive abilities among young children are warranted.

Sleep Patterns in Chinese Preschool Children: A Population-Based Study

STUDY OBJECTIVES

This study aimed to (1) provide data on normal sleep patterns in Chinese preschool children, (2) identify cross-cultural differences of sleep patterns among children from China and other countries, (3) estimate the prevalence of sleep duration not meeting the optimal amount, and (4) characterize delayed weekend sleep pattern.

METHODS

A population-based sample of 1,610 children aged 3-6 years was recruited from 10 cities across China. Parents completed questions about their child's sleep patterns adapted from the Children's Sleep Habits Questionnaire (CSHQ).

RESULTS

The mean bedtime was 9:31 PM, wake time was 7:27 AM, nighttime sleep duration was 9 hours 30 minutes, daytime sleep duration was 1 hour 31 minutes, and total sleep duration was 11 hours 2 minutes. The children had a shorter nighttime sleep duration but longer daytime naps, resulting in no differences in total sleep duration compared with counterparts predominantly in the west. Of the children, 85.3% met the recommended amount of sleep of 10 to 13 hours, and 10.8% slept fewer than 10 hours. The prevalence of sleep less than 10 hours was higher in older children and children from eastern China. Children went to bed and woke up more than 30 minutes later on weekends than weekdays, accounting for 40.1% and 50%, respectively. Children in western China showed longer delay than children in eastern China (P < .05).

CONCLUSIONS

Age- and region-specific variability of sleep patterns are reported as well as insufficient sleep and delayed weekend sleep pattern in Chinese preschool children. The cross-cultural difference of sleep patterns was in temporal placement rather than sleep duration.

Sleep and psychiatric symptoms in young child psychiatric outpatients

BACKGROUND

Sleep may underlie psychiatric symptoms in young children. However, not many studies have reported on sleep and its associations with symptoms in young child psychiatric patients.

OBJECTIVES

To assess the amount and quality of sleep and how sleep associates with psychiatric symptoms in young child psychiatric patients. Furthermore, we evaluated how sleep and daytime somnolence differed in patients and their age- and gender-matched controls.

METHOD

The sample consisted of 139 3- to 7-year-old child psychiatric outpatients and 139 age- and gender-matched controls from community. We evaluated sleep and daytime somnolence with the Sleep Disturbance Scale for Children in all children and psychiatric symptoms with Child Behaviour Checklist (CBCL) in the patient group. Family background information was collected from the patients.

RESULTS

Of the patients, 31.6% had a significant sleep problem and 14.4% slept too little. The most typical sleep problems were restless sleep (31.7%), morning tiredness (21.6%) and difficulties getting to sleep at night (18.7%). All types of sleep problems were associated with CBCL total, internalising and externalising problems (all p-values < .01). We observed a strong association between all types of sleep problems and emotionally reactive subscale ( p-value < .001). Furthermore, parent-reported sleep problems increased significantly the risk of having high scores on total (odds ratio (OR) = 5.3, 95% confidence interval (CI) = [2.2, 12.6], p < .001), external (OR = 3.7, 95%, CI = [1.6, 8.5], p < .01) and internal (OR = 2.5, 95% CI = [1.1, 5.5], p < .05) scores after controlling for age, gender, family structure and parent's educational level. Even mild sleep disturbance increased the intensity of psychiatric symptoms. Compared to controls, patients slept less ( p < .001) and had significantly more frequent restless sleep, nightmares and morning and daytime somnolence.

CONCLUSION

Sleep problems and too little sleep are prevalent in young child psychiatric patients, and they relate strongly to the intensity of psychiatric symptoms. Identification and treatment of sleep problems should be a routine part of the treatment plan for young child psychiatric patients. The results emphasise the need for assessing sleep in young child psychiatric patients, as treating the sleep problem may reduce psychiatric symptoms.

Parental restriction reduces the harmful effects of in-bedroom electronic devices

OBJECTIVE

To investigate whether school readiness could be affected by placing electronic devices (EDs) in children's bedroom and whether the relationship was moderated by parental restriction and family socioeconomic status (SES).

DESIGN

This is a cross-sectional study with bedroom ED placement and parental restriction reported by parents. Multiple linear regressions were used to test the relationship between school readiness and ED placement. Multiple regression with interaction terms were used to test whether the effect was consistent with and without parental restriction.

SETTING

Kindergartens randomly selected from two districts of different socioeconomic backgrounds in Hong Kong, China.

PATIENTS

556 young children attending the third year of kindergarten.

MAIN OUTCOME MEASURES

Children's school readiness was rated by teachers using the Chinese Early Development Instrument.

RESULTS

556 preschoolers (mean age 5.46; 51.8% girls) from 20 kindergartens participated in this study. About 30% of parents placed at least one ED in their children's bedroom. After controlling for sex and SES, the placement of television in the bedroom was associated with lower overall school readiness (β -1.11, 95% CI -1.80 to -0.42) and the placement of game console was associated with lower social competence (β-0.94, 95% CI -1.74 to -0.15). Such harmful effect was more prominent among lower SES families and could be partially alleviated with parental restriction.

CONCLUSION

ED placement in children's bedroom was associated with lower school readiness, particularly among lower SES families. Parental restriction might help to alleviate the harm.

Consensus Statement of the American Academy of Sleep Medicine on the Recommended Amount of Sleep for Healthy Children: Methodology and Discussion

ABSTRACT

Members of the American Academy of Sleep Medicine developed consensus recommendations for the amount of sleep needed to promote optimal health in children and adolescents using a modified RAND Appropriateness Method. After review of 864 published articles, the following sleep durations are recommended: Infants 4 months to 12 months should sleep 12 to 16 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 1 to 2 years of age should sleep 11 to 14 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 3 to 5 years of age should sleep 10 to 13 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 6 to 12 years of age should sleep 9 to 12 hours per 24 hours on a regular basis to promote optimal health. Teenagers 13 to 18 years of age should sleep 8 to 10 hours per 24 hours on a regular basis to promote optimal health. Sleeping the number of recommended hours on a regular basis is associated with better health outcomes including: improved attention, behavior, learning, memory, emotional regulation, quality of life, and mental and physical health. Regularly sleeping fewer than the number of recommended hours is associated with attention, behavior, and learning problems. Insufficient sleep also increases the risk of accidents, injuries, hypertension, obesity, diabetes, and depression. Insufficient sleep in teenagers is associated with increased risk of self-harm, suicidal thoughts, and suicide attempts.

COMMENTARY

A commentary on this article apears in this issue on page 1439.