Toddler's self-regulation strategies in a challenge context are nap-dependent

Sleep Deficiency in Young Children

There is growing public health concern about the high prevalence of sleep deficiency in early childhood and the associated risk for sleep-associated poor health outcomes, including metabolic, cardiovascular, and mental health. The recent shift to conceptualize sleep health as a multidimensional construct, influenced by socioecological factors, highlights the potential role of sleep in health disparities. Understanding the development of sleep health and the emergence of sleep disorders in early life is a current priority in pediatric sleep research. Future behavioral sleep interventions should consider the multiple socioecological influences on children's sleep health and be tested using inclusive sampling methods.

Behavioral Intervention that Extends Sleep Duration Leads to Greater Self-Control in School-Aged Children

OBJECTIVE

Short sleep and evening phase preference associate with impaired self-control, yet few studies have assessed the efficacy of sleep extension for improving this behavioral domain. Thus, this secondary analysis of a behavioral sleep intervention measured whether an intervention that enhanced children's sleep also affected self-control. Differences by chronotype were also explored.

METHODS

Sixty-seven children (8-11 yr), who reportedly slept <9.5 hr/d, were randomized to either a control or sleep intervention condition (i.e., 4-session behavioral intervention to enhance sleep by 1-1.5 hr/night). Chronotype was assessed using the Child Chronotype Questionnaire at baseline, and self-control was assessed using the Self-Control Rating Scale (SCRS, a caregiver report) at baseline and 8 weeks postrandomization. Total sleep time (TST) was measured using wrist actigraphy for 1 week at both baseline and 8 weeks postrandomization. Partial correlations and mixed-model ANOVAs were used for statistical analyses, with age as a covariate.

RESULTS

At baseline, children with shorter TST (r = -0.29, p = 0.02) and an evening preference (r = 0.26, p = 0.049) were perceived as having lower self-control by their caregivers. Significant condition*time interaction effects were found for TST ( p < 0.001) and SCRS score ( p = 0.046): From baseline to follow-up, children randomized to the sleep intervention exhibited a significant increase in TST and were perceived as having greater self-control by their caregiver; children randomized to the control condition exhibited no change in TST or in SCRS score. The condition*chronotype*time interaction effect was not significant.

CONCLUSION

A brief sleep intervention that enhanced TST also resulted in enhanced caregiver reported self-control in school-age children. Results add to the growing evidence for the importance of sleep health in children.

Blindness affects the developmental trajectory of the sleeping brain

Sleep plays a crucial role in brain development, sensory information processing, and consolidation. Sleep spindles are markers of these mechanisms as they mirror the activity of the thalamocortical circuits. Spindles can be subdivided into two groups, slow (10-13 Hz) and fast (13-16 Hz), which are each associated with different functions. Specifically, fast spindles oscillate in the high-sigma band and are associated with sensorimotor processing, which is affected by visual deprivation. However, how blindness influences spindle development has not yet been investigated. We recorded nap video-EEG of 50 blind/severely visually impaired (BSI) and 64 sighted children aged 5 months to 6 years old. We considered aspects of both macro- and micro-structural spindles. The BSI children lacked the evolution of developmental spindles within the central area. Specifically, young BSI children presented low central high-sigma and high-beta (25-30 Hz) event-related spectral perturbation and showed no signs of maturational decrease. High-sigma and high-beta activity in the BSI group correlated with clinical indices predicting perceptual and motor disorders. Our findings suggest that fast spindles are pivotal biomarkers for identifying an early developmental deviation in BSI children. These findings are critical for initial therapeutic intervention.

Maternal beliefs and cognitions about naps in infants and toddlers

Infant and toddler sleep affects family functioning and maternal mental health and well-being. However, little is known about parental perceptions regarding child daytime sleep. The current study aimed to determine maternal beliefs and cognitions of child naps, assessing how naps impact perceived child and maternal functioning. Mothers of 465 infants and toddlers (4-36mos; M = 18.5mos) in the United States completed an online questionnaire addressing those aims, including maternal perception of naps after napping cessation. Most mothers agreed that naps were important (98%). Over two-thirds wanted to change something about their child's naps and one-quarter reported that naps were problematic. About half wished their child fell asleep faster/easier for naps, and one-third wished they napped longer. Few reported that child naps were more trouble than they were worth (4%). Most mothers believed that when their child naps well their child is in a better mood (97%), more easy-going (96%), has fewer tantrums (89%), and listens better (84%, toddlers). Finally, most mothers believed that their child's naps were important for their own day (94%), improved their own mood (87%) made them feel calmer (90%), and enabled them to nap (51%), do more in the house (92%), complete work (87%), spend time with others (78%), and spend time doing things for themselves (80%).   Conclusion: Considering most mothers believed their child's naps were important for their child and themselves, yet many wanted to change something about those naps and/or thought naps were problematic, intervention development is warranted focusing on daytime sleep issues to improve both child and family functioning. What is Known: • Although maternal perceptions of overnight sleep in young children has been well studied, little is known about beliefs and cognitions regarding daytime sleep. What is New: • Mothers of infants and toddlers believe naps are beneficial for their child and are important for child mood, behavior, and sleep. • Mothers find child naps valuable for themselves, allowing time for other activities.

Sleep duration in preschool age and later behavioral and cognitive outcomes: an individual participant data meta-analysis in five European cohorts

Short sleep duration has been linked to adverse behavioral and cognitive outcomes in schoolchildren, but few studies examined this relation in preschoolers. We aimed to investigate the association between parent-reported sleep duration at 3.5 years and behavioral and cognitive outcomes at 5 years in European children. We used harmonized data from five cohorts of the European Union Child Cohort Network: ALSPAC, SWS (UK); EDEN, ELFE (France); INMA (Spain). Associations were estimated through DataSHIELD using adjusted generalized linear regression models fitted separately for each cohort and pooled with random-effects meta-analysis. Behavior was measured with the Strengths and Difficulties Questionnaire. Language and non-verbal intelligence were assessed by the Wechsler Preschool and Primary Scale of Intelligence or the McCarthy Scales of Children's Abilities. Behavioral and cognitive analyses included 11,920 and 2981 children, respectively (34.0%/13.4% of the original sample). In meta-analysis, longer mean sleep duration per day at 3.5 years was associated with lower mean internalizing and externalizing behavior percentile scores at 5 years (adjusted mean difference: - 1.27, 95% CI [- 2.22, - 0.32] / - 2.39, 95% CI [- 3.04, - 1.75]). Sleep duration and language or non-verbal intelligence showed trends of inverse associations, however, with imprecise estimates (adjusted mean difference: - 0.28, 95% CI [- 0.83, 0.27] / - 0.42, 95% CI [- 0.99, 0.15]). This individual participant data meta-analysis suggests that longer sleep duration in preschool age may be important for children's later behavior and highlight the need for larger samples for robust analyses of cognitive outcomes. Findings could be influenced by confounding or reverse causality and require replication.

Early childhood naps initiate emotional memory processing in preparation for enhanced overnight consolidation

Early childhood naps support emotional memory, but benefits are only observed after overnight sleep. Whether emotional memory consolidation occurs during naps, or whether napping only prepares memories for overnight consolidation is unknown. We investigated whether naps protect emotional memories from interference, indicating consolidation. Between 2018 and 2020, 63 children in western Massachusetts preschools (30 female, 33 male; 33-67 months; 23.8% Hispanic, 87.3% White) learned faces paired with negative or neutral descriptions, followed by nap or wake. Before delayed recognition, half completed an interference task. Without interference, napping benefited recognition. With interference, children recognized fewer negative faces post-nap (compared to wake), with overnight sleep attenuating this difference. Results suggest that naps initially destabilize emotional memories, possibly reflecting partial processing that promotes long-term consolidation.

"Katerina gets mad": Infants' physiological and behavioral responses to co-viewing educational, self-regulatory media

A growing body of research has focused on the physiological impact of media on older children and adolescents. Less research has been focused on the potential physiological impact of media on infants and younger children, especially media designed to be age appropriate and educational in content. In this study, we examined respiratory sinus arrhythmia (RSA) in infants (N = 269, M_age  = 17.13 months) while they co-viewed an educational video clip that modeled emotion regulation and contrasted their physiological response to an unoccupied baseline and a frustration paradigm (arm-restraint). Given parent reports showing the calming effect of educational media viewing in young children, we anticipated that a similar pattern of calming would be observed physiologically in infants. Results showed that relative to baseline, most infants demonstrated an increase in RSA while co-viewing, suggesting greater parasympathetic (regulatory) activation consistent with behavioral calming. However, infants who demonstrated vagal withdrawal during co-viewing (decrease in RSA) were more likely to have parents who used a tablet to help infants go to sleep at night. Vagal withdrawal was also associated with increased levels of negative affect observed during the co-viewing task. Findings are discussed in relation to the contextual effect of co-viewing age-appropriate, educational media on children's physiological responses.

Randomized controlled trial to enhance children's sleep, eating, and weight

BACKGROUND

The present study assessed the efficacy of a behavioral intervention to enhance children's sleep and reduce caloric intake and body mass index (BMI) change.

METHODS

Seventy-eight children 8-11 years old who slept 9.5 h/night or less were randomized to the sleep intervention or to no treatment control. The primary outcome was 2-month change in the actigraph-estimated sleep period; changes in reported caloric intake, percent calories from fat, and BMI/BMI z-score (BMIz) were assessed.

RESULTS

Children randomized to intervention enhanced their sleep period by 40 ± 7 min/night relative to control (p < 0.001), and were more likely to increase their sleep period by 30 min/night or more (52% versus 15%, p = 0.003). No differences were observed for reported dietary intake or BMI/BMIz. However, in post-hoc analyses collapsing across groups, those who increased sleep by 30 min/night or more had lower BMI (-0.31 kg/m², p = 0.01) and BMIz (-0.07, p = 0.03) and reported fewer percent calories from fat at 2 months (-2.2%, p = 0.04).

CONCLUSIONS

A brief behavioral intervention can enhance children's sleep, but did not result in changes in caloric intake or weight status. Enhancing sleep by 30 min/night or more may be beneficial for weight regulation.

IMPACT

A brief behavioral intervention improved children's nocturnal sleep relative to no treatment control. Given the many benefits of a good night's sleep across domains of functioning, findings have significant implications for children's health and wellbeing. There were no differences between groups on eating behaviors or BMI. However, across groups, children who increased their sleep period by at least 30 min/night, reported reduced intake from fat and evidenced lower BMI at 2 months. Thus, a brief intervention can improve sleep and may have potential benefits for weight regulation.

Associations of sleep and emotion regulation processes in childhood and adolescence - a systematic review, report of methodological challenges and future directions

Sleep and emotions are closely associated; however, the methodological challenges in the examination of sleep and the processes of emotion regulation in children and adolescents have not been investigated so far. Additionally, there is the demand to identify the levels of emotion regulating processes in which problematic or restricted sleep causes effect. Experimental sleep deprivation as well as prevalent sleep problems have been found to have negative influence on mental health and regulating functions. This review focuses first on the methodological protocols of the included studies. Subsequently, the results are summarized in the context of a multilevel model of emotion regulation. Thereafter, suggestions for future directions are given. Sleep problems and sleep deprivation are associated with a decrease of functional emotion regulating behavior and impaired emotion generation, and prolonged sleep enhances better mood and affect states, positive emotion expression, and faster sensory processing in response to emotional stimuli. This literature review highlights the limitations in current research, focusing on types of measurements, task characteristics, and data analysis. At the conclusion, suggestions are given for the future research direction in the field of sleep and emotion regulation in children and adolescents.

Investigating the effects of sleep and sleep loss on the different stages of episodic emotional memory: A narrative review and guide to the future

For two decades, sleep has been touted as one of the primary drivers for the encoding, consolidation, retention, and retrieval of episodic emotional memory. Recently, however, sleep's role in emotional memory processing has received renewed scrutiny as meta-analyses and reviews have indicated that sleep may only contribute a small effect that hinges on the content or context of the learning and retrieval episodes. On the one hand, the strong perception of sleep's importance in maintaining memory for emotional events may have been exacerbated by publication bias phenomena, such as the "winner's curse" and "file drawer problem." On the other hand, it is plausible that there are sets of circumstances that lead to consistent and reliable effects of sleep on emotional memory; these circumstances may depend on factors such as the placement and quality of sleep relative to the emotional experience, the content and context of the emotional experience, and the probes and strategies used to assess memory at retrieval. Here, we review the literature on how sleep (and sleep loss) influences each stage of emotional episodic memory. Specifically, we have separated previous work based on the placement of sleep and sleep loss in relation to the different stages of emotional memory processing: (1) prior to encoding, (2) immediately following encoding during early consolidation, (3) during extended consolidation, separated from initial learning, (4) just prior to retrieval, and (5) post-retrieval as memories may be restructured and reconsolidated. The goals of this review are three-fold: (1) examine phases of emotional memory that sleep may influence to a greater or lesser degree, (2) explicitly identify problematic overlaps in traditional sleep-wake study designs that are preventing the ability to better disentangle the potential role of sleep in the different stages of emotional memory processing, and (3) highlight areas for future research by identifying the stages of emotional memory processing in which the effect of sleep and sleep loss remains under-investigated. Here, we begin the task of better understanding the contexts and factors that influence the relationship between sleep and emotional memory processing and aim to be a valuable resource to facilitate hypothesis generation and promote important future research.

The Moderating Role of Stress Response on the Relationship Between Subjective Sleep Quality and Suicide Ideation in Adolescence

OBJECTIVE

Problems sleeping and stress are known to contribute to the development of suicide ideation. However, it is unclear how these risk factors interact longitudinally. The purpose of this study was to determine the impact of problems sleeping on the development of suicide ideation in adolescence one year later and how the relationship changes with the addition of stress as a moderator.

METHOD

Data were collected from 153 adolescents (M age = 12.8, SD = 1.6) over three years as part of a larger study. Participants completed the MINI-Kid and Youth Self-Report, which were used to assess for suicidality. The Stress scale of the YSR was used to measure stress. Participants also completed the Adolescent Sleep Wake Scale, which was used to assess their perceptions of their sleep quality.

RESULTS

Logistic moderation analyses demonstrated a significant interaction between ASWS and YSR Stress in the prediction of suicide ideation one year later, Wald χ²(1)=4.57, OR = 0.68, p < 0.05. Results demonstrated higher odds of endorsing SI as stress increased when sleep quality was poor (OR = 21.51) compared to when sleep quality was high (OR = 4.03), suggesting that adequate sleep may act as a protective factor against suicide ideation.

CONCLUSIONS

The results are indicative of long-term consequences of sleep on adolescent mental health, particularly when faced with high levels of stress. These results may have significant clinical implications for suicide prevention efforts as this relationship may help identify at-risk adolescents prior to the initial experience of suicide ideation.

Sleep Deficiency in Young Children

There is growing public health concern about the high prevalence of sleep deficiency in early childhood and the associated risk for sleep-associated poor health outcomes, including metabolic, cardiovascular, and mental health. The recent shift to conceptualize sleep health as a multidimensional construct, influenced by socioecological factors, highlights the potential role of sleep in health disparities. Understanding the development of sleep health and the emergence of sleep disorders in early life is a current priority in pediatric sleep research. Future behavioral sleep interventions should consider the multiple socioecological influences on children's sleep health and be tested using inclusive sampling methods.

Daily fluctuations in young children's persistence

Children's behavior changes from day to day, but the factors that contribute to its variability are understudied. We developed a novel repeated measures paradigm to study children's persistence by capitalizing on a task that children complete every day: toothbrushing (N = 81; 48% female; 36-47 months; 80% white, 14% Multiracial, 10% Hispanic, 2% Asian, 1% Black; 1195 observations collected between January 2019 and March 2020). Children brushed longer on days when their parents used more praise (d = .23) and less instruction (d = -.22). Sensitivity to mood, sleep, and parent stress varied across children, suggesting that identifying the factors that shape an individual child's persistence could lead to personalized interventions.

Association of nighttime sleep with behaviors in Japanese early childhood

BACKGROUND

Preschool children in Asian countries, including Japan, sleep for a shorter duration at night than those in Europe and the USA. We examined the effects of the nighttime sleep duration on behavioral development in early childhood in Japan.

METHODS

We used data from a large Japanese nationwide, population-based, longitudinal survey that began in 2001. We restricted the study participants to children born after 37 gestational weeks, with a birth weight ≥ 2500 g and singleton births (n = 41 890). The nighttime sleep duration was examined at 2.5 years old. Responses to survey questions regarding age-appropriate behavior at 5.5 years old were used as indicators of behavioral development. We conducted logistic regression analyses with adjustment for confounding factors, with ≥11 h of nighttime sleep as the reference group.

RESULTS

The odds ratios for children who had ≤9 h of nighttime sleep, which was associated with being unable to listen with fidgeting and being unable to remain patient, were 1.26 (95% confidence interval, 1.14-1.39) and 1.27 (1.16-1.38), respectively. Children who had an irregular nighttime sleep duration were associated with age-appropriate behavioral inabilities. These results were similar in children who usually and sometimes took naps to those before stratification by the frequency of napping.

CONCLUSION

A short nighttime sleep duration especially affects hyperactivity and impulsivity. An irregular nighttime sleep duration increases the inability to perform overall age-appropriate behaviors more than a short sleep duration. Ensuring a regular and sufficient nighttime sleep duration in early childhood is important for healthy behavioral development.

A time series analysis of the relation between motor skill acquisition and sleep in infancy

To systematically examine the relation between motor milestone onset and disruption of night sleep in infancy, three families kept microgenetic, prospective, daily checklist diaries of their infants' motor behavior and sleep (197-313 observation days; 19,000 diary entries). Process control and interrupted time series analyses examined whether deviations from the moving average for night wakings and evening sleep duration were temporally linked to motor skill onset and tested for meaningful differences in individual sleep patterns before and after skill onset. Model assumptions defined skill onset as first day of occurrence or as mastery and moving average windows as 3, 7, or 14 days. Changes in infants' sleep patterns were associated with changing expertise for motor milestones. The temporal relation varied depending on infant and sleep parameter. Intensive longitudinal data collection may increase our understanding of micro-events in infant development.

Self-Regulation in Pediatric Nursing Literature: An Evolutionary Concept Exploration

The concept of self-regulation appears frequently in nursing literature. Although the concept is well developed in nonnursing theories, its application in nursing has not been explored adequately. Most nursing authors address self-regulation in one of two ways. Some publish findings without a strong theoretical understanding of self-regulation. Others publish studies using a conglomeration of theorists' self-regulatory explanations without properly contextualizing the theoretical elements for nursing practice. For this concept exploration, the authors used Rodgers, B. L. (2005). Developing nursing knowledge: Philosophical traditions and influences Lippincott, Williams & Wilkins, evolutionary concept analysis method to determine the current use of self-regulation in pediatric nursing literature and trace the concept's recent development, changes, and expansion. This work provides a representation of self-regulation based on existing healthcare studies and suggests steps for concept clarification that could promote accurate use of the concept in future research.

The effect of sleep deprivation and restriction on mood, emotion, and emotion regulation: three meta-analyses in one

STUDY OBJECTIVES

New theory and measurement approaches have facilitated nuanced investigation of how sleep loss impacts dimensions of affective functioning. To provide a quantitative summary of this literature, three conceptually related meta-analyses examined the effect of sleep restriction and sleep deprivation on mood, emotion, and emotion regulation across the lifespan (i.e. from early childhood to late adulthood).

METHODS

A total of 241 effect sizes from 64 studies were selected for inclusion, and multilevel meta-analytic techniques were used when applicable.

RESULTS

There was a moderate, positive effect of sleep loss on negative mood (g = 0.45), which was stronger for studies with younger samples, as well as a large, negative effect of sleep loss on positive mood (g = -0.94). For negative mood only, studies that used total sleep deprivation had larger effect sizes than studies that restricted sleep. After correcting for publication bias, a modest but significant negative effect for sleep loss on emotion (g = -0.11) was found; the valence of emotional stimuli did not change the direction of this effect, and type of sleep manipulation was also not a significant moderator. Finally, sleep restriction had a small, negative effect on adaptive emotion regulation (g = -0.32), but no significant impact on maladaptive emotion regulation (g = 0.14); all studies on adaptive emotion regulation were conducted with youth samples.

CONCLUSIONS

Sleep loss compromises optimal affective functioning, though the magnitude of effects varies across components. Findings underscore the importance of sleep for healthy affective outcomes.

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 Problems, Cumulative Risks, and Psychological Functioning in Early Childhood

BACKGROUND

Sleep problems and cumulative risk factors (e.g., caregiver depression, socioeconomic disadvantage) have independently been linked to adverse child development, but few studies have examined the interplay of these factors. We examined whether cumulative risk exposure moderated the link between sleep problems, including insomnia and poor sleep health, and child psychological outcomes.

METHODS

205 caregiver-child dyads (child Mage = 3.3 years; 53.7% girls; 62.9% Black, 22.4% non-Latinx White, and 4.4% Latinx; 85.4% maternal caregiver reporter) completed child sleep, family sociodemographic, and child psychological functioning (internalizing, externalizing, and executive functioning) questionnaires. Indexes of cumulative risk exposure, insomnia symptoms, and poor sleep health were created.

RESULTS

Ninety percent of children had ≥1 cumulative risks, 62.9% had ≥1 insomnia symptom, and 84.5% had ≥1 poor sleep health behavior. Increased insomnia symptoms were significantly associated with increased child internalizing, externalizing, and global executive functioning impairments controlling for child age, race/ethnicity, and sex. Poor sleep health behaviors were associated with internalizing concerns. Cumulative risk exposure was not associated with outcomes but moderated the association between insomnia symptoms and all psychological outcomes, such that children with higher cumulative risk exposure and insomnia symptoms had the greatest impairments. Children with the poorest sleep health behaviors and highest cumulative risks had the greatest internalizing concerns.

CONCLUSIONS

Insomnia symptoms in particular are associated with poor child outcomes, which are exacerbated when accompanied by greater cumulative risk exposure. Clinicians should assess sleep when treating early psychological concerns, especially within the context of increased cumulative risks.

Socioeconomic disadvantage and sleep in early childhood: Real-world data from a mobile health application

OBJECTIVES

To examine whether increased socioeconomic disadvantage, indexed using a measure of community distress, was associated with variation in caregiver-reported early childhood sleep patterns and problems in a large US sample using a mobile health application (app).

DESIGN

Cross-sectional.

SETTING

Data were collected using the free, publicly available Johnson's Bedtime© baby sleep app.

PARTICIPANTS

A total of 14,980 caregivers (85.1% mothers) of children ages 6-35.9 months (M = 13.88 months; 52.6% boys) participated in this study.

MEASURES

Caregivers reported on child sleep using the Brief Infant Sleep Questionnaire-Revised. Socioeconomic disadvantage was indexed by zip code using the Distressed Communities Index (DCI), which combines seven US census indicators of socioeconomic disadvantage. DCI scores range from prosperous (lowest quintile) to distressed (highest quintile).

RESULTS

Socioeconomic disadvantage was significantly associated with later bedtimes, longer sleep onset latency, and shorter nighttime and 24-hour (total) sleep duration, with children living in distressed communities showing the poorest sleep. However, caregivers living in distressed communities reported a significantly lower prevalence of overall child sleep problems (43% vs 58% in prosperous communities), and more confidence in managing child sleep (42% vs 34% in prosperous communities).

CONCLUSIONS

Children living in the most distressed communities have the poorest reported sleep patterns and bedtime behaviors; however, their caregivers are less likely to report problematic child sleep. These findings highlight the need for community-level sleep health promotion interventions, as well as further investigation of caregiver perceptions about child sleep and sleep health promotion among families living in socioeconomically disadvantaged contexts.

Pediatric sleep health: It matters, and so does how we define it

In 2014, Buysse published a novel definition of sleep health, raising awareness for the importance of this construct for individuals, populations, clinical care, and research. However, the original definition focused on adults, with the recommendation that it should be adapted for children and adolescents. As children live within a complex and dynamic system, and may not always have control over their own sleep, this theoretical review will examine and apply Buysse's five dimensions of sleep health within the context of pediatrics. In addition, using examples from the pediatric sleep literature we introduce a modified definition that takes into consideration the influence of the socio-ecological system within which children live, and the sleep-related behaviors that are critical in supporting or hindering sleep health. Finally, we discuss how the proposed theoretical framework, Peds B-SATED, can be applied to clinical practice, research, and training in the field of pediatric sleep.

The Association between Diurnal Sleep Patterns and Emotions in Infants and Toddlers Attending Nursery

Background: Childcare programs often include mandatory naptime during the day. Loss of daytime sleep could lead to a moderate-to-large decrease in self-regulation, emotion processing, and learning in early childhood. Nevertheless, daytime sleep has been less accurately studied than nighttime sleep. This study aims to explore the relationship between diurnal sleep habits in nursery settings, nocturnal sleep quality, and post-nap emotional intensity in infants and toddlers. Methods: Data of 92 children (52 girls, 40 boys) aged 6 to 36 months were obtained. Sleep habits as well as positive and negative emotions were monitored by educators during nursery times through a sleep and emotion diary for two weeks. Results: Explorative analyses showed that diurnal sleep hours decreased across age groups (except for females aged 25–36 months) and that all age groups had a lower amount of nocturnal sleep than is recommended by the National Sleep Foundation. Partial correlation analysis showed significant correlation between daytime sleep onset latency and positive emotions. Mediation analyses showed that daytime napping is relevant for emotional functioning independently of nocturnal sleep quality. Conclusions: Daytime sleep in early childhood seems to be linked to the management of positive and negative emotions and could play a role in healthy development of emotional processes.

Longitudinal sleep problem trajectories are associated with multiple impairments in child well-being

BACKGROUND

This study examined whether distinct sleep problem trajectories from infancy through middle childhood were associated with multiple aspects of child well-being at ages 10-11 years.

METHODS

Data were from the first six waves of the Longitudinal Study of Australian Children - Birth Cohort (5,107 children recruited at birth). Caregivers reported on child sleep problems at each time point. A combination of caregiver-reported, teacher-reported and child-completed tasks were used to index child well-being outcomes at ages 10-11 years including emotional/behavioural functioning (internalizing and externalizing symptoms; self-control), health-related quality of life, cognitive skills and academic achievement.

RESULTS

Latent class analysis identified five distinct sleep problem trajectories over time: persistent sleep problems through middle childhood (7.7% of the sample), limited infant/preschool sleep problems (9.0%), increased middle childhood sleep problems (17.0%), mild sleep problems over time (14.4%) and no sleep problems (51.9%). Compared to those with no sleep problems, children with persistent sleep problems had the greatest impairments across all outcomes except cognitive skills (perceptual reasoning), with moderate to large effect sizes. Children with increased middle childhood sleep problems similarly experienced greater internalizing and externalizing symptoms and worse quality of life, but few academic impairments. Both the limited infant/preschool sleep problems and mild increases over time trajectories also showed internalizing concerns and worse caregiver-reported quality of life, although effects were smaller than the other sleep trajectories.

CONCLUSIONS

The linkages between sleep problems and negative child outcomes across domains underscore the importance of early identification and targeted intervention to address sleep problems and promote child well-being.

Sleep and Early Brain Development

The early years of life are characterized by dramatic developmental changes. Within this important time period lies the transition from newborn to childhood. Sleep is one of the primary activities of the brain during early development and plays an important role in healthy cognitive and psychosocial development in early life. This paper will first review the normal sleep characteristics and their development in neonates and children, including architecture of sleep, development of a healthy sleep rhythm in early childhood, sleep recommendations and cultural disparity, as well as important factors for establishing a healthy sleep pattern during the first years of life, such as regular and consistent bedtime routine, safe and comfortable sleep environment, and appropriate sleep onset associations. This paper then provides recent updates of evidence of the effects of sleep on early brain development, particularly on learning and memory, emotional regulation, and general cognitive development through behavioral and neurophysiological studies. As regards the mechanism, many experimental sleep deprivation studies in animals and adults have attempted to explain the underlying mechanisms of sleep on cognition and the emotional brain. Future studies are expected to delineate the effects of sleep on brain structural and functional networks in the developing brain with the marked development of image acquisition approaches and the novel analysis tools for infants and young children in recent years.

Sex Differences in the Association between Household Chaos and Body Mass Index z-Score in Low-Income Toddlers

Background: Associations between household chaos and childhood overweight have been identified, but the mechanisms of association are not clearly established in young children, with some studies linking higher chaos to increased obesity risk, whereas other studies link higher chaos to lower obesity risk. Given the lack of consistent findings and early sex differences in vulnerability to chaos, we examined child sex as a moderator of the chaos-child overweight association. We also tested these associations with self-regulation, as self-regulation has been implicated in understanding the chaos-obesity risk association in low-income toddlers. Methods: Parent-reported household chaos and observed child self-regulation were collected at baseline [n = 132; M age 23.0 months (standard deviation 2.8)]. Children's body mass index z-score (BMIz) was measured at 33 months. Multivariate linear regression models were used to assess whether child sex moderated the chaos-BMIz association. A three-way interaction between chaos, child sex, and self-regulation was also tested. Results: Child sex moderated the chaos-BMIz association (b = -0.11, p = 0.04) such that chaos was positively associated with BMIz among boys (b = 0.12, p = 0.003), but unrelated in girls (b = 0.01, p = 0.78). A three-way interaction with self-regulation indicated that a positive chaos-BMIz association existed only for boys with average (b = 0.12, p = 0.004) and low (b = 0.22, p < 0.001) self-regulation. Conclusions: Boys with poor self-regulation may be particularly vulnerable to obesogenic effects of chaotic households.

Trajectories of sleep in Child Protective Services (CPS)-referred children predict externalizing and internalizing symptoms in early childhood

BACKGROUND

Previous studies have established links between poor sleep and negative developmental outcomes. However, it remains unclear whether young maltreated children demonstrate atypical sleep patterns and whether sleep duration is associated with emotional and behavioral problems.

OBJECTIVE

Explore trajectories of sleep among Child Protective Services (CPS)-referred children and examine whether sleep duration is significantly associated with externalizing and internalizing symptoms, even when controlling for the home environment.

PARTICIPANTS

Participants included 197 children (Mage at first assessment = 10.24 months, SD = 6.39) whose parents were referred to CPS due to allegations of maltreatment.

METHODS

Parents completed sleep diaries for their children at up to five time-points and the preschool version of the Child Behavior Checklist (CBCL) when children were approximately 2 years of age (Mage = 26.40 months, SD = 3.36). The Home Observation for Measurement of the Environment Scale (HOME) assessed the quality of the early home environment.

RESULTS

Results from latent growth curve modeling demonstrated that CPS-referred children significantly varied (B = 3.28, SE = 0.90, p < .001) in the amount they slept in a 24-hour period at baseline (i.e., 4.1 months of age), and the amount of total sleep in a 24-hour period significantly decreased across time (B1 = -0.03, SE = 0.01, p < .001). When controlling for characteristics of the home environment, total sleep in a 24-hour period at baseline significantly inversely predicted externalizing (B = -1.03, SE = 0.06, p < .001) and internalizing symptoms (B = -0.19, SE = 0.03, p < .001) in early childhood.

CONCLUSIONS

This study is an important first step in exploring trajectories of sleep among CPS-referred children. Findings underscore sleep as a promising target for interventions aimed at promoting regulation and highlight the need for future research to examine sleep in maltreated children as a predictor of later developmental outcomes.

Sleep Patterns, Problems and Ecology among Toddlers in Families with a Child Protective Services Maltreatment Referral

PURPOSE

To describe sleep patterns, problems, and ecology among toddlers (13 to 36 months) from families referred to Child Protective Services (CPS) for maltreatment and to compare sleep duration among a subgroup (24- to 36-month-olds) to previously published population-based data.

DESIGN AND METHODS

A secondary analysis of a larger longitudinal study was conducted. Participants included 113 parent-toddler dyads recruited out of CPS offices based on having a recent maltreatment referral. Parents reported about their toddler's sleep at two time points (approximately six months apart).

RESULTS

At the earlier and later time points, respectively, mean sleep duration was 11.03 and 10.90 h (nighttime), 1.36 and 1.36 h (daytime), and 12.47 and 12.28 h (total 24-h). Of the toddlers, 24% and 17% had two or more nighttime awakenings, 34% and 33% had at least a somewhat hard time falling asleep, and 25% and 26% had difficulty sleeping alone. Mean bedtimes were 8:50 pm and 8:58 pm. Nighttime sleeping arrangement/location, nap arrangement/location, and method of falling asleep at night varied. Compared to the population-based data, nighttime sleep duration was 43 min longer and nap duration was 46 min shorter in the CPS sample.

CONCLUSIONS

Symptoms of behavioral sleep problems were common in this sample of toddlers from families referred to CPS for maltreatment. Distribution of sleep, but not total 24-hour sleep, differed significantly between the CPS sample and the population-based data.

PRACTICE IMPLICATIONS

Nurses caring for toddlers from families involved with CPS can play an integral role promoting sleep health and addressing behavioral sleep problems.

Sleep Problems, Daily Napping Behavior, and Social-Emotional Functioning among Young Children from Families Referred to Child Protective Services

OBJECTIVE/BACKGROUND

Insufficient and/or poor-quality sleep may contribute to poor social-emotional well-being, and vice versa, among young children who have experienced maltreatment. This study examined longitudinal associations between sleep and social-emotional functioning among a sample of infants and toddlers from families involved with Child Protective Services (CPS) for maltreatment.

PARTICIPANTS

Participants were 123 parents and their infant or toddler (baseline age 10 to 24 months) from families referred to CPS for maltreatment.

METHODS

Data were collected at baseline and at 3, 6 and 9 months post-baseline. At all time points, parents completed a questionnaire about their child's social-emotional functioning including internalizing behavior, externalizing behavior, and competence in social-emotional skills and social relatedness. At 3 months post-baseline, parents reported about their child's sleep problems and daily napping behavior.

RESULTS

Higher baseline externalizing behavior was associated with a greater propensity for sleep problems at 3 months post-baseline. Sleep problems at 3 months post-baseline were associated with higher internalizing and higher externalizing behavior at 9 months post-baseline. Daily napping at 3 months post-baseline was associated with lower internalizing behavior, lower externalizing behavior, and higher competence at 9 months post-baseline.

CONCLUSIONS

Among this sample of young children from families involved with CPS for maltreatment, parents' concerns about their child having a sleep problem longitudinally associated with children's internalizing and externalizing behavior. Children's daily napping behavior longitudinally associated with later internalizing behavior, externalizing behavior, and competence.

Midday napping in children: associations between nap frequency and duration across cognitive, positive psychological well-being, behavioral, and metabolic health outcomes

STUDY OBJECTIVES

Poor sleep and daytime sleepiness in children and adolescents have short- and long-term consequences on various aspects of health. Midday napping may be a useful strategy to reduce such negative impacts. The effect of habitual napping on a wide spectrum of cognitive, behavioral, psychological, and metabolic outcomes has not been systematically investigated.

METHODS

This study characterized midday napping habits in 3819 elementary school children from the China Jintan Cohort Study. In 2011, weekly nap frequency and average duration were collected once from students at grades 4-6. Prior to their completion of elementary school at grade 6 (in 2011-2013 respective to each grade), the following outcomes were collected once: behavioral and academic achievement evaluated by teachers, and self-reported positive psychology measures including grit, self-control, and happiness. IQ tests were conducted on a subgroup. Metabolic indices, including body mass index and fasting glucose concentration, were measured through physical exams. For the whole sample, we assessed associations between napping and each outcome, adjusted for sex, grade, school location, parental education, and time in bed at night. We also conducted stratified analyses on grade 6 (cross-sectional), grade 4 (2-year gap), and grade 5 (1-year gap) data.

RESULTS

Overall, napping was significantly associated with higher happiness, grit, and self-control, reduced internalizing behavior problem, higher verbal IQs, and better academic achievement, although specific patterns varied across frequency and duration for different outcomes. More limited significant associations were found for decreased externalizing behavior problems, compared to non-nappers, while no significant associations were found for performance IQ and metabolic outcomes.

CONCLUSIONS

Results indicate benefits of regular napping across a wide range of adolescent outcomes, including better cognition, better psychological wellness, and reduced emotional/behavioral problems. The current study underscores the need for further large-scale intervention studies to establish causal effects.

Adolescent profiles of ethnicity/race and socioeconomic status: Implications for sleep and the role of discrimination and ethnic/racial identity

The present study seeks to explore the intersectionality of ethnicity/race and socioeconomic status (SES) among ethnic/racial minority adolescents in their developmental contexts, examining its implications for sleep disparities and the roles of discrimination and ethnic/racial identity (ERI; i.e., adolescents' understanding and feelings about who they are in relation to their ethnic/racial group). With 350 adolescents (Asian 41.4%, Black, 21.7%, and Latinx 36.9%, female=69.1%, Mage=14.27), we conducted a latent class analysis (LCA) to identify latent classes of adolescents' ethnicity/race, ethnic/racial diversity in their schools and neighborhoods along with SES of their families, schools, and neighborhoods. Next, with hierarchical regression, we tested the association between class membership and subjective and objective sleep duration and quality, followed by the moderating effect of discrimination and ERI. We expected to find adolescents living in low diversity and low SES across various developmental contexts to experience lower levels of subjective and objective sleep duration and quality compared to their counterparts. We also expected to find exacerbating effects of discrimination and ERI exploration, and protective effects of ERI commitment in these associations. Three latent groups were identified (C1: "Black/Latinx adolescents in low/moderate SES families in varying diversity and low SES schools and neighborhoods," C2: "Predominantly Latinx adolescents in low SES families and moderate diversity and SES schools and neighborhoods," and C3: "Predominantly Asian adolescents in low/moderate SES families in moderate/high diversity and SES schools and neighborhoods"). The class memberships to C1 and C2 were associated with compromised sleep duration and quality compared to C3. An interaction effect of discrimination was found for C1 in subjective sleep duration and for C2 in objective sleep duration. While no interactions were found for ERI, ERI commitment had a direct association with objective sleep duration and quality. Interpretations and implications for intersectionality approach in studies on sleep disparities and the roles of discrimination and ERI are discussed.

Considering Sleep, Mood, and Stress in a Family Context: A Preliminary Study

Background: During the first years of life, parental sleep strongly depends on child’s sleep quality. Poor parental sleep may relate to increased stress and negative mood. However, there is a lack of sleep studies focusing on all family members. This study aimed to investigate the relationship between sleep, mood, and stress in mothers, fathers and children. Methods: Data were obtained from 65 parental couples and 65 children (2 to 36 months). Data on sleep for all family members and stress of parents were completed by both mothers and fathers through questionnaires and sleep diaries. Results: Toddlers’ positive mood before nocturnal sleep was significantly associated with reduced wake times after sleep onset. Mothers reported worse sleep quality compared to fathers. Shorter sleep onset latency in fathers and better sleep efficiency in mothers were linked with better self-reported mood upon awakening. In mothers, but not in fathers, poor sleep quality was associated with higher perceived stress. Conclusion: Results suggest bidirectional relationships between sleep and mood in children, mothers and fathers. Moreover, results evidence poorer sleep in mothers, compared to fathers, which was linked with increased parenting stress. This gender gap should be further considered in studies with larger samples and in clinical contexts.

Parenting and toddler self-regulation in low-income families: What does sleep have to do with it?

Toddlerhood is a sensitive period in the development of self-regulation, a set of adaptive skills that are fundamental to mental health and partly shaped by parenting. Healthy sleep is known to be critical for self-regulation; yet, the degree to which child sleep alters interactive child-parent processes remains understudied. This study examines associations between observed parenting and toddler self-regulation, with toddler sleep as a moderator of this association. Toddlers in low-income families (N = 171) and their mothers were videotaped during free play and a self-regulation challenge task; videos were coded for mothers' behavior and affect (free play) and toddlers' self-regulation (challenge task). Mothers reported their child's nighttime sleep duration via questionnaire. Results revealed significant Sleep × Maternal Negative Affect and Sleep × Maternal Negative Control interactions. Children who did not experience negative parenting had good self-regulation regardless of their nighttime sleep duration. For children who did experience negative parenting, self-regulation was intact among those who obtained more nighttime sleep, but significantly poorer among children who were getting less nighttime sleep. Thus, among children who were reported to obtain less nighttime sleep, there were more robust associations between negative parenting and poorer self-regulation than among toddlers who were reported to obtain more sleep.

Sleep duration and quality are associated with eating behavior in low-income toddlers

OBJECTIVE

The present study examined whether different sleep health parameters (duration, timing, and quality) are associated with obesity-related eating behaviors including emotional overeating, food responsiveness, enjoyment of food, satiety responsiveness, and eating in the absence of hunger (EAH), during toddlerhood.

DESIGN

Among 134 low-income 33-month-old children, parents reported on child sleep parameters, including sleep quality (Children's Sleep Wake Scale; CSWS) and usual bedtimes and wake times on weekdays and weekends (weeknight sleep duration, weekday-to-weekend bedtime delay). Child eating behaviors were assessed using both observed and parent-report measures. Child Emotional Overeating, Food Responsiveness, Enjoyment of Food, and Satiety Responsiveness were measured by parent report using the Child Eating Behavior Questionnaire-Toddler. Observed child EAH was evaluated by measuring kilocalories of palatable foods consumed following a meal. Multivariable linear regression was used to examine the associations between sleep parameters and eating behaviors.

RESULTS

Poorer child sleep quality was associated with greater Emotional Overeating (standardized β = -0.20 (SE 0.09), p < .05) and greater Food Responsiveness (β = -0.18 (SE 0.09), p < .05). Shorter child nighttime sleep duration was associated with greater EAH kcal consumed (standardized β = -0.22 (SE 0.09), p < .05). Child bedtime delay was not associated with any of the eating behaviors, and no child sleep variables were associated with either Enjoyment of Food or Satiety Responsiveness.

CONCLUSIONS

Shorter nocturnal sleep duration and poorer sleep quality during toddlerhood were associated with some, but not all, of the obesity-related eating behaviors. Poor sleep health may promote childhood obesity risk through different eating behavior pathways. As children growing up in poverty may experience greater sleep decrements, sleep duration and sleep quality may be important targets for intervention among low-income families with young children.

A review of developmental consequences of poor sleep in childhood

Sleep is a fairly diverse and complex construct to operationalize in a scientific and naturalistic context. We report a systematic review and meta-analysis of reviews published in the last 5 years on poor sleep and developmental outcomes. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, 42 articles (or 1117 studies) qualified. They reported outcomes related to poor sleep investigated as sleep disorders (38.1%), sleep 'in general' (26.2%), sleep duration (23.8%), in terms of circadian rhythm (4.8%), intra-individual variability (2.4%), and napping (2.4%). Sleep was primarily subjectively reported (30.2%), yet the methodology of sleep assessment was often neither tabulated nor discussed. Overall, most papers had a health-scope, being primarily weight problems expressed as body mass index. Its relationship with performance was measured with the Wechsler intelligence tests, the child behavior checklist and the continuous performance test, whereas meta-analytic papers specifically focused on cognition with sleep disorder (i.e. sleep-disordered breathing; 38.6%), on health (i.e. weight) with sleep duration (25%) and behavior with sleep 'in general' (15.9%), having a high true variance. Nevertheless, an aggregated effect size d of 0.35 (95% confidence interval: 0.27-0.42) suggests that poor sleep is moderately affecting a child's performance and health. In conclusion, poor sleep can no longer be disregarded, yet methodologies that are more rigorous and a scope beyond health may foster a better understanding of the role of (poor) sleep across childhood neurodevelopment.

Youth Screen Media Habits and Sleep: Sleep-Friendly Screen Behavior Recommendations for Clinicians, Educators, and Parents

With the widespread use of portable electronic devices and the normalization of screen media devices in the bedroom, insufficient sleep has become commonplace. In a recent literature review, 90% of included studies found an association between screen media use and delayed bedtime and/or decreased total sleep time. This pervasive phenomenon of pediatric sleep loss has widespread implications. There is a need for basic, translational, and clinical research examining the effects of screen media on sleep loss and health consequences in children and adolescents to educate and motivate clinicians, teachers, parents and youth themselves to foster healthy sleep habits.

Sleep Tight, Act Right: Negative Affect, Sleep and Behavior Problems During Early Childhood

Temperamental negative affect and insufficient sleep have been independently associated with behavior problems during early childhood. However, it is unknown whether these factors interact to contribute to behavioral difficulties in young children. The current study examined the interactions between temperamental negative affect and both sleep onset time and sleep midpoint, assessed by actigraphy, in predicting externalizing and internalizing behaviors in a sample of 117 children (34-69 months of age). Children with high temperamental negative affect and either later sleep onset time or later sleep midpoint were more likely to exhibit externalizing and internalizing behaviors. These results emphasize the association between temperamental negative affect and behavioral difficulties, particularly for children with insufficient sleep.

Association of Sleep and Circadian Activity Rhythm with Emotional Face Processing among 12-month-old Infants

Sleep and circadian rhythmicity both play an important role in human’s cognitive functioning, yet the way in which early development of sleep and circadian rhythm affects cognitive processes and social learning in infants remains less understood. We examined the association of sleep and circadian activity rhythm (CAR) with face and emotional information processing in 12-month old infants. Face processing was measured by eye tracking, whereby infants’ scanning patterns and pupil dilations were calculated when they were presented with neutral, pleasant and unpleasant faces. Infants with better sleep quality (i.e., less waking after sleep onset) and lower sleep-wake pattern variability (i.e., higher inter-daily stability) exhibited a higher eyes over mouth fixation ratio (EMR). Infants with longer total sleep time showed larger pupil diameter changes in response to emotional facial expressions, more closely resembling the responses of adults. Our findings suggest the role of sleep and circadian rhythm in waking cognition and have implications for understanding the early development of social learning in young children.

Targeting self-regulation to promote health behaviors in children

Poor self-regulation (i.e., inability to harness cognitive, emotional, motivational resources to achieve goals) is hypothesized to contribute to unhealthy behaviors across the lifespan. Enhancing early self-regulation may increase positive health outcomes. Obesity is a major public health concern with early-emerging precursors related to self-regulation; it is therefore a good model for understanding self-regulation and health behavior. Preadolescence is a transition when children increase autonomy in health behaviors (e.g., eating, exercise habits), many of which involve self-regulation. This paper presents the scientific rationale for examining self-regulation mechanisms that are hypothesized to relate to health behaviors, specifically obesogenic eating, that have not been examined in children. We describe novel intervention protocols designed to enhance self-regulation skills, specifically executive functioning, emotion regulation, future-oriented thinking, and approach bias. Interventions are delivered via home visits. Assays of self-regulation and obesogenic eating behaviors using behavioral tasks and self-reports are implemented and evaluated to determine feasibility and psychometrics and to test intervention effects. Participants are low-income 9-12 year-old children who have been phenotyped for self-regulation, stress, eating behavior and adiposity through early childhood. Study goals are to examine intervention effects on self-regulation and whether change in self-regulation improves obesogenic eating.

Systematic review of the relationships between sleep duration and health indicators in the early years (0-4 years)

Background

The objective of this systematic review was to examine for the first time the associations between sleep duration and a broad range of health indicators in children aged 0 to 4 years.

Methods

Electronic databases were searched with no limits on date or study design. Included studies (published in English or French) were peer-reviewed and met the a priori determined population (apparently healthy children aged 1 month to 4.99 years), intervention/exposure/comparator (various sleep durations), and outcome criteria (adiposity, emotional regulation, cognitive development, motor development, growth, cardiometabolic health, sedentary behaviour, physical activity, quality of life/well-being, and risks/injuries). The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Due to high levels of heterogeneity across studies, narrative syntheses were employed.

Results

A total of 69 articles/studies (62 unique samples) met inclusion criteria. Data across studies included 148,524 unique participants from 23 countries. The study designs were randomized trials (n = 3), non-randomized interventions (n = 1), longitudinal studies (n = 16), cross-sectional studies (n = 42), or longitudinal studies that also reported cross-sectional analyses (n = 7). Sleep duration was assessed by parental report in 70% of studies (n = 48) and was measured objectively (or both objectively and subjectively) in 30% of studies (n = 21). Overall, shorter sleep duration was associated with higher adiposity (20/31 studies), poorer emotional regulation (13/25 studies), impaired growth (2/2 studies), more screen time (5/5 studies), and higher risk of injuries (2/3 studies). The evidence related to cognitive development, motor development, physical activity, and quality of life/well-being was less clear, with no indicator showing consistent associations. No studies examined the association between sleep duration and cardiometabolic biomarkers in children aged 0 to 4 years. The quality of evidence ranged from “very low” to “high” across study designs and health indicators.

Conclusions

Despite important limitations in the available evidence, longer sleep duration was generally associated with better body composition, emotional regulation, and growth in children aged 0 to 4 years. Shorter sleep duration was also associated with longer screen time use and more injuries. Better-quality studies with stronger research designs that can provide information on dose-response relationships are needed to inform contemporary sleep duration recommendations.

Electronic supplementary material

The online version of this article (10.1186/s12889-017-4850-2) contains supplementary material, which is available to authorized users.

Racial/ethnic sleep disparities in US school-aged children and adolescents: a review of the literature

Sleep is essential for optimal health, well-being, and cognitive functioning, and yet nationwide, youth are not obtaining consistent, adequate, or high-quality sleep. In fact, more than two-thirds of US adolescents are sleeping less than 8 hours nightly on school nights. Racial and ethnic minority children and adolescents are at an increased risk of having shorter sleep duration and poorer sleep quality than their white peers. In this review, we critically examined and compared results from 23 studies that have investigated racial/ethnic sleep disparities in American school-aged children and adolescents ages 6-19 years. We found that White youth generally had more sufficient sleep than minority youth, Hispanics had more than Blacks, and there was inconclusive evidence for Asians and other minorities. Recommendations for researchers include the following: (1) explore underlying causes of the disparities of these subpopulations, with a particular interest in identifying modifiable causes; (2) examine factors that may be impacted by racial/ethnic sleep disparities; (3) use a multidimensional approach to measuring sleep disparities; and (4) examine how beliefs about sleep are patterned by race/ethnicity. Understanding sleep disparities can inform interventions, policies, and educational programs to minimize sleep disparities and their impact on health, psychological, and educational outcomes.

Exploring the nap paradox: are mid-day sleep bouts a friend or foe?

The mid-day nap, sometimes called a siesta, is a ubiquitous occurrence across the lifespan. It is well established that in addition to reducing sleepiness, mid-day naps offer a variety of benefits: memory consolidation, preparation for subsequent learning, executive functioning enhancement, and a boost in emotional stability. These benefits are present even if a sufficient amount of sleep is obtained during the night prior. However, we present a paradox: in spite of these reported benefits of naps, frequent napping has also been associated with numerous negative outcomes (eg, cognitive decline, hypertension, diabetes), particularly in older populations. This association exists even when statistically controlling for relevant health- and sleep-affecting determinants. An emerging hypothesis suggests inflammation is a mediator between mid-day naps and poor health outcomes, yet further research is necessary. Given this, it may be premature to 'prescribe' naps as a health enhancer. Herein, we aggregate findings from several branches of sleep research (eg, developmental neuroscience, cognitive neuroscience, sleep medicine) to critically examine the paradoxical role of naps in cognitive and somatic health. This review uncovers gaps in the literature to guide research opportunities in the field.

Naps Enhance Executive Attention in Preschool-Aged Children

Objective

Executive attention is impaired following sleep loss in school-aged children, adolescents, and adults. Whether naps improve attention relative to nap deprivation in preschool-aged children is unknown. The aim of this study was to compare executive attention in preschool children following a nap and an interval of wake.

Method

Sixty-nine children, 35-70 months of age, completed a Flanker task to assess executive attention following a nap and an equivalent interval of wake.

Results

Overall, accuracy was greater after the nap compared with the wake interval. Reaction time(s) did not differ between the nap and wake intervals. Results did not differ between children who napped consistently and those who napped inconsistently, suggesting that naps benefit executive attention of preschoolers regardless of nap habituality.

Conclusions

These results indicate that naps enhance attention in preschool children. As executive attention supports executive functioning and learning, nap promotion may improve early education outcomes.

Testing Reciprocal Links Between Trouble Getting to Sleep and Internalizing Behavior Problems, and Bedtime Resistance and Externalizing Behavior Problems in Toddlers

Sleep problems are associated with problematic adjustment in toddlers, but less is known regarding the direction of association between specific sleep problems and adjustment. To address this gap, we used data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (N = 1001) to examine reciprocal associations between sleep problems and behavior problems from 24- to 36-months. Results from cross-lagged path models suggested specificity of associations between type of sleep problem and behavior problem. Specifically, there were reciprocal associations between trouble getting to sleep and internalizing problems, and unidirectional links between externalizing problems and bedtime resistance from 24- to 36-months. Internalizing and externalizing problems at 24 months, however, predicted increases in bedtime resistance from 24- to 36-months for boys, but not girls. Findings highlight specific relations between sleep problems and internalizing and externalizing problems during toddlerhood, and the importance of examining sex differences.

Acute sleep restriction increases dietary intake in preschool-age children

Epidemiological findings suggest short sleep duration is associated with overweight and obesity across the lifespan. In adults, experimental sleep loss increases caloric intake more than total daily energy needs, thus leading to weight gain. To date, little is known about the relationship between sleep restriction and dietary intake in preschool children. Healthy children (n = 10; 41.2 ± 5.4 months; 5 females) followed a strict sleep schedule for 5 days before each experimental condition: 1 day of baseline sleep (nap and scheduled bedtime/wake time) and 1 day of sleep restriction (no-nap and ~2.3 h bedtime delay). Standardized parent-report dietary intake measures were obtained on baseline, sleep restriction and sleep recovery (ad libitum sleep opportunity in the 24-h following sleep restriction) days. As designed, children slept ~3 h less on the sleep restriction than the baseline day (P < 0.001), with no significant differences in sleep between baseline and recovery days (verified with actigraphy). Repeated-measures anovas indicated differences across conditions in total kilocalories, sugar, carbohydrate and fat intake (all P < 0.05; no differences in protein). Post hoc tests revealed that compared with baseline, children consumed 21% more kilocalories, 25% more sugar and 26% more carbohydrates on the day of sleep restriction, as well as 14% more kilocalories and 23% more fat on the day of sleep recovery (all P < 0.05). Findings suggest that acute sleep loss increases dietary intake in preschoolers both on the day of and the day after sleep restriction. Increased kilocalorie intake may promote weight gain over time and be a mechanism through which short sleep contributes to childhood obesity risk.

Variation in common preschool sleep problems as an early predictor for depression and anxiety symptom severity across time

BACKGROUND

Child and adolescent psychopathology has been linked to increased sleep problems, but there has been less investigation of this relationship in younger samples with early-onset psychopathology. This study examined three specific but commonly observed aspects of sleep behaviors in young children - (i) Sleep onset latency, (ii) Refusal to sleep alone, and (iii) Nighttime awakenings - measured during preschool, and investigated whether these sleep problems predicted anxiety and/or depression across the next 6 years until school age (ages 9-13).

METHODS

Data were analyzed from N = 292 participants from a prospective longitudinal study of preschool-age children (ages 3-6). At baseline, parent-reported clinical interviews of psychiatric symptoms, as well as sleep problems were conducted using the Preschool-Age Psychiatric Assessment (PAPA). Follow-up clinical interviews were also conducted annually through school age using the Childhood and Adolescent Psychiatric Assessment (CAPA).

RESULTS

Parent-reported sleep onset latency and refusal to sleep alone were significant independent predictors of MDD and anxiety severity, but not ADHD severity across time, even after controlling for family income-to-needs ratio and maternal internalizing psychopathology. In exploratory analyses using only healthy preschoolers, parent-reported sleep onset latency and refusal to sleep alone also predicted anxiety severity.

CONCLUSIONS

We demonstrate that specific, yet relatively common sleep problems predict diagnostic severity of depression and anxiety across time, but not ADHD. Increased clinical attention to and screening for sleep onset latency and refusal to sleep alone during preschool may be warranted.

Development of nap neurophysiology: preliminary insights into sleep regulation in early childhood

Although all young children nap, the neurophysiological features and associated developmental trajectories of daytime sleep remain largely unknown. Longitudinal studies of napping physiology are fundamental to understanding sleep regulation during early childhood, a sensitive period in brain and behaviour development and a time when children transition from a biphasic to a monophasic sleep-wakefulness pattern. We investigated daytime sleep in eight healthy children with sleep electroencephalography (EEG) assessments at three longitudinal points: 2 years (2.5-3.0 years), 3 years (3.5-4.0 years) and 5 years (5.5-6.0 years). At each age, we measured nap EEG during three randomized conditions: after 4 h (morning nap), 7 h (afternoon nap) and 10 h (evening nap) duration of prior wakefulness. Developmental changes in sleep were most prevalent in the afternoon nap (e.g. decrease in sleep duration by 30 min from 2 to 3 years and by 20 min from 3 to 5 years). In contrast, nap sleep architecture (% of sleep stages) remained unchanged across age. Maturational changes in non-rapid eye movement sleep EEG power were pronounced in the slow wave activity (SWA, 0.75-4.5 Hz), theta (4.75-7.75 Hz) and sigma (10-15 Hz) frequency ranges. These findings indicate that the primary marker of sleep depth, SWA, is less apparent in daytime naps as children mature. Moreover, our fundamental data provide insight into associations between sleep regulation and functional modifications in the central nervous system during early childhood.

Increased Sleep Depth in Developing Neural Networks: New Insights from Sleep Restriction in Children

Brain networks respond to sleep deprivation or restriction with increased sleep depth, which is quantified as slow-wave activity (SWA) in the sleep electroencephalogram (EEG). When adults are sleep deprived, this homeostatic response is most pronounced over prefrontal brain regions. However, it is unknown how children’s developing brain networks respond to acute sleep restriction, and whether this response is linked to myelination, an ongoing process in childhood that is critical for brain development and cortical integration. We implemented a bedtime delay protocol in 5- to 12-year-old children to obtain partial sleep restriction (1-night; 50% of their habitual sleep). High-density sleep EEG was assessed during habitual and restricted sleep and brain myelin content was obtained using mcDESPOT magnetic resonance imaging. The effect of sleep restriction was analyzed using statistical non-parametric mapping with supra-threshold cluster analysis. We observed a localized homeostatic SWA response following sleep restriction in a specific parieto-occipital region. The restricted/habitual SWA ratio was negatively associated with myelin water fraction in the optic radiation, a developing fiber bundle. This relationship occurred bilaterally over parieto-temporal areas and was adjacent to, but did not overlap with the parieto-occipital region showing the most pronounced homeostatic SWA response. These results provide evidence for increased sleep need in posterior neural networks in children. Sleep need in parieto-temporal areas is related to myelin content, yet it remains speculative whether age-related myelin growth drives the fading of the posterior homeostatic SWA response during the transition to adulthood. Whether chronic insufficient sleep in the sensitive period of early life alters the anatomical generators of deep sleep slow-waves is an important unanswered question.