Short sleep duration is associated with teacher-reported inattention and cognitive problems in healthy school-aged children

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.

Parental and Child Sleep: Children with Vision Impairment, Autistic Children, and Children with Comorbid Vision Impairment and Autism

BACKGROUND

Parents report associations between children's sleep disturbances and behaviors. Children with neurodevelopmental conditions (e.g., Williams Syndrome and autism) are consistently reported to experience increased sleeping problems. Sleep in children with vision impairment and children with a dual diagnosis of vision impairment and autism remains understudied.

METHODS

Our exploratory study compared sleep profiles in 52 children (aged 4-12 years) and their parents (n = 37), across four groups: children with vision impairment (VI; n = 9), autism (n = 10), comorbid vision impairment + autism (n = 6), and typically developing children (n = 27). Childhood sleep was measured using the parental report Childhood Sleep Habits Questionnaire and sleep diaries. Children's cognitive functioning was measured using digit span, semantic, and phonemic verbal fluency measures. Parental sleep was measured via the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale.

RESULTS

Clinically disordered sleep was reported in all child groups (p ≤ 0.001), particularly children with VI + autism. Age, not sleep quality/quantity, predicted cognitive task performance in TD and autistic groups, but not in VI and VI + autism groups. The child's diagnosis affected parental sleep, particularly in children with a dual diagnosis of VI + autism.

CONCLUSIONS

All participants experienced problematic sleep to varying degrees. Those most affected were children and parents in the VI + autism group, suggesting that autism may be the main driver of sleep problems in our sample.

ADHD Symptoms and Sleep Problems During Middle Childhood: The Indirect Effect of Peer Victimization

The present cross-sectional study evaluated whether traditional and/or cyber peer victimization served as mechanisms linking ADHD symptoms to sleep disturbance and sleep impairment in a sample of 284 third- through fifth-grade students (51.9% boys; 50.4% Hispanic/Latine) from two elementary schools in the United States. ADHD symptoms were assessed using teacher ratings. Children provided reports of their traditional and cyber victimization as well as their sleep disturbance and impairment. Results from path analysis models revealed significant indirect effects of traditional victimization on the links from ADHD symptoms to sleep disturbance and impairment. There was also a significant indirect effect of cyber victimization on the link from ADHD symptoms to sleep impairment. These findings suggest that experiences of traditional and cyber peer victimization may need to be addressed among children exhibiting ADHD symptoms in order to mitigate their risk for sleep problems and downstream effects on other domains of psychosocial functioning.

Childhood sleep: physical, cognitive, and behavioral consequences and implications

BACKGROUND

Sleep problems in children have been increasingly recognized as a major public health issue. Previous research has extensively studied and presented many risk factors and potential mechanisms for children's sleep problems. In this paper, we aimed to identify and summarize the consequences and implications of child sleep problems.

DATA SOURCES

A comprehensive search for relevant English language full-text, peer-reviewed publications was performed focusing on pediatric sleep studies from prenatal to childhood and adolescence in a variety of indexes in PubMed, SCOPUS, and Psych Info published in the past two decades. Both relevant data-based articles and systematic reviews are included.

RESULTS

Many adverse consequences are associated with child sleep deficiency and other sleep problems, including physical outcomes (e.g., obesity), neurocognitive outcomes (e.g., memory and attention, intelligence, academic performance), and emotional and behavioral outcomes (e.g., internalizing/externalizing behaviors, behavioral disorders). Current prevention and intervention approaches to address childhood sleep problems include nutrition, exercise, cognitive-behavioral therapy for insomnia, aromatherapy, acupressure, and mindfulness. These interventions may be particularly important in the context of coronavirus disease 2019. Specific research and policy strategies can target the risk factors of child sleep as well as the efficacy and accessibility of treatments.

CONCLUSIONS

Given the increasing prevalence of child sleep problems, which have been shown to affect children's physical and neurobehavioral wellbeing, understanding the multi-aspect consequences and intervention programs for childhood sleep is important to inform future research direction as well as a public health practice for sleep screening and intervention, thus improving sleep-related child development and health.

Sleep Modulates Alcohol Toxicity in Drosophila

Alcohol abuse is a significant public health problem. While considerable research has shown that alcohol use affects sleep, little is known about the role of sleep deprivation in alcohol toxicity. We investigated sleep as a factor modulating alcohol toxicity using Drosophila melanogaster, a model for studies of sleep, alcohol, and aging. Following 24 h of sleep deprivation using a paradigm that similarly affects males and females and induces rebound sleep, flies were given binge-like alcohol exposures. Sleep deprivation increased mortality, with no sex-dependent differences. Sleep deprivation also abolished functional tolerance measured at 24 h after the initial alcohol exposure, although there was no effect on alcohol absorbance or clearance. We investigated the effect of chronic sleep deprivation using mutants with decreased sleep, insomniac and insulin-like peptide 2, finding increased alcohol mortality. Furthermore, we investigated whether pharmacologically inducing sleep prior to alcohol exposure using the GABA_A-receptor agonist 4,5,6,7-tetrahydroisoxazolo(5,4-c)pyridin-3-ol (THIP) mitigated the effects of alcohol toxicity on middle-aged flies, flies with environmentally disrupted circadian clocks, and flies with short sleep. Pharmacologically increasing sleep prior to alcohol exposure decreased alcohol-induced mortality. Thus, sleep prior to binge-like alcohol exposure affects alcohol-induced mortality, even in vulnerable groups such as aging flies and those with circadian dysfunction.

Association between adolescent smoking and subsequent college completion by parent education - A national longitudinal study

BACKGROUND

Educational attainment is a social determinant of health associated with better quality of life and health outcomes. Current understanding of the association between adolescent smoking and college completion is limited. This study examined the association between adolescent smoking and subsequent college completion and how it varied by parent education in a longitudinal study of U.S. adolescents followed into young adulthood.

METHODS

Data were collected annually from a nationally representative cohort of 10th graders who participated in the NEXT Generation Health Study (2009 -2017; N = 1407). Participants reported if they smoked during 10th-12th grades (2009-2013). Self-report college completion was assessed in 2017. Parent reported their educational attainment at baseline. Weighted logistic regression models were used to assess the association between adolescent smoking during 10th-12th grades and subsequent college completion in the entire sample and stratified by parent educational attainment, adjusting for demographics, depressive symptoms, alcohol use, and parental monitoring.

RESULTS

Overall, adolescents who smoked during 10th-12th grade had lower odds of subsequently completing college compared to those who did not smoke (AOR=0.33, 95%CI=0.20-0.57). This association was stronger among those whose parents had ≤high school education (AOR=0.08, 95% CI=0.02-0.31) and some college education (AOR=0.18, 95%CI=0.08-0.39).

DISCUSSION

Adolescents from lower educational attainment households showed disproportionately stronger association between adolescent smoking and subsequent college completion. Future research needs to determine whether and how strategies to reduce adolescent smoking may promote educational attainment especially among adolescents whose parents have less than a college education.

Higher Tablet Use Is Associated With Better Sustained Attention Performance but Poorer Sleep Quality in School-Aged Children

There are growing concerns that increased screen device usage may have a detrimental impact on classroom behaviour and attentional focus. The consequences of screen use on child cognitive functioning have been relatively under-studied, and results remain largely inconsistent. Screen usage may displace the time usually spent asleep. The aim of this study was to examine associations between screen use, behavioural inattention and sustained attention control, and the potential modifying role of sleep. The relations between screen use, behavioural inattention, sustained attention and sleep were investigated in 162 6- to 8-year-old children, using parent-reported daily screen use, the SWAN ADHD behaviour rating scale, The sustained attention to response task and the children’s sleep habits questionnaire. Tablet use was associated with better sustained attention performance but was not associated with classroom behavioural inattention. Shorter sleep duration was associated with poorer behavioural inattention and sustained attention. Sleep quality and duration did not act as mediators between screen usage and behavioural inattention nor sustained attention control. These findings suggest that careful management of the amount of time spent on electronic screen devices could have a beneficial cognitive impact on young children. The results also highlight the critical role of sleep in enhancing both behavioural attention and sustained attention, which are essential for supporting cognitive development and learning.

A Systematic Review of Sleep and Circadian Rhythms in Children with Attention Deficit Hyperactivity Disorder

OBJECTIVE

Children and adults with ADHD often report sleep disturbances that may form part of the etiology and/or symptomatology of ADHD. We review the evidence for sleep changes in children with ADHD.

METHODS

Systematic review with narrative synthesis assessing sleep and circadian function in children aged 5 to 13 years old with a diagnosis of ADHD.

RESULTS

148 studies were included for review, incorporating data from 42,353 children. We found that sleep disturbances in ADHD are common and that they may worsen behavioral outcomes; moreover, sleep interventions may improve ADHD symptoms, and pharmacotherapy for ADHD may impact sleep.

CONCLUSION

Sleep disturbance may represent a clinically important feature of ADHD in children, which might be therapeutically targeted in a useful way. There are a number of important gaps in the literature. We set out a manifesto for future research in the area of sleep, circadian rhythms, and ADHD.

Sleep, Classroom Behavior, and Achievement Among Children of Color in Historically Disinvested Neighborhoods

Children of color are more likely to have poor sleep health than White children, placing them at risk for behavioral problems in the classroom and lower academic performance. Few studies, however, have utilized standardized measures of both classroom behavior and achievement. This study examined whether children's sleep (parent and teacher report) in first grade concurrently related to independent observations of classroom behavior and longitudinally predicted achievement test scores in second grade in a sample of primarily Black (86%) children (n = 572; age = 6.8) living in historically disinvested neighborhoods. Higher teacher-reported child sleepiness was associated with lower adaptive behaviors and higher problem behaviors in the classroom, and predicted lower achievement. Parent-reported bedtime resistance and disordered breathing also predicted lower achievement.

Association between sleep habits/disorders and emotional/behavioral problems among Japanese children

Actual sleep status and the association between sleep habits/disorders and emotional/behavioral problems among children in the development stage have not been fully clarified. A questionnaire survey was conducted on the sleep habits/disorders (Brief Child Sleep Questionnaire; BCSQ) and emotional/behavioral problems (Strengths and Difficulties Questionnaire; SDQ) of 87,548 children enrolled in ordinary classes in nine grade levels from the first grade of elementary school to the third grade of junior high school from December 2009 to April 2010. As school grade increased, children's bedtimes were delayed and sleep duration was reduced by 2.0 h over the nine grade levels. Based on the BCSQ, 18.3% of children were judged to have some type of sleep disorder, and about 30% to 40% of children had sleep symptoms at bedtime, during sleep, and at wake time. Multiple regression analysis showed that emotional and behavioral problems were associated with presence of any sleep symptom, longer sleep latency, and longer awake time after sleep onset, whereas total sleep time was not. Sleep symptoms at wake time were most strongly associated with emotional and behavioral problems. Status of sleep habits/disorders should be considered when interpreting emotional/behavioral problems in school-age children.

Impact of pre-sleep habits on adolescent sleep: an Italian population-based study

OBJECTIVE

Several evidences demonstrate that pre-sleep habits may negatively impact adolescent sleep, yet few data exist on Italian population. This study aimed to investigate the relationship between pre-sleep habits, use of technology/activity and sleep in Italian adolescents.

METHODS

Self-report questionnaires including Italian version of School Sleep Habits Survey and use of technology/activity (eg smartphone, PC) at bedtime were administered to 972 adolescents (13-19 years) from Lombardia. We stratified the sample in five groups according to the age: Group I (13-14 years), Group II (15 years), Group III (16 years), Group IV (17 years), Group V (18-19 years).

RESULTS

Our descriptive analysis reveals a different sleep profile across age-groups: Group III showed highest percentage of bad sleep (26.7%) and frequent nocturnal awakenings (24.1%), Group V had the highest percentage of insufficient sleep (40,4%) and difficulty falling asleep (42.7%) and Group IV presented an elevated difficulty in waking up in the morning (70.1%). A significant negative correlation was found in total group between use of smartphone, internet and studying/doing homework and total sleep time. The use of smartphone, internet videogames, listening to music and studying/doing homework was positively associated with delayed bedtime.

CONCLUSIONS

This study confirms the great impact of pre-sleep habits, and in particular the use of technology on adolescent sleep. Our results demonstrate that sleep is strongly altered among Italian adolescents using electronic devices in evening. The type of technology may be related to specific sleep profile, emphasizing the importance of stratification analyses to identify associated factors to sleep problems.

Sleep Characteristics in Italian Children During Home Confinement Due to Covid-19 Outbreak

OBJECTIVE

Italy faced one of the first large clusters of COVID-19 infections worldwide. Home confinement and social distancing could have negatively impacted sleep habits and prevalence of sleep disorders in children, which may be also linked with altered emotional processes. The present study focused on clinical aspects related to sleep, insomnia and emotions in Italian children aged 0-to-12 years during home confinement due to COVID-19 outbreak.

METHOD

An online survey was systematically distributed in all Italian territories by contacting regional offices of the Italian Ministry of Instruction, University and Research (MIUR) and schools with available contact. All respondents had to be parents of at least one child aged 0 to 12 years old. Information on sociodemographic variables, sleep habits, sleep health behaviors, sleep disorders and mood were collected.

RESULTS

Parents of 2361 children (mean age: 8.1 ± 2.62 years; 1148 females; 1213 males) answered the survey. 1.2% of children was between 0 and 2 years old; 15.3% within 3 to 5 years and 83.3% within 6 and 12 years. In all group ages, late bedtime was observed (most of them after 9 p.m.). 59.4% of all children presented at least one clinical diagnostic criterion for childhood insomnia. Logistic regression model showed that presence of at least one criterion for childhood insomnia was associated to younger age, negative mood, current parental insomnia, being the only child, presence of any other sleep disorder, and sleep hygiene behaviors.

CONCLUSIONS

Data indicate an alarming increase of prevalence of insomnia related problems in Italian children during home confinement with respect to previous data. This was found to be associated with poor sleep hygiene and negative mood. Clinical programs targeting insomnia, sleep health behaviors and emotional processes should be implemented in pediatric primary care in order to prevent the development of sleep problems in a post-pandemic situation.

Sleep and neurobehavioral functioning in survivors of pediatric cancer

OBJECTIVES

Sleep problems are a common late effect in survivors of pediatric cancer. Growing literature suggests deficits in sleep functioning may be related to more impairing neurobehavioral outcomes. The purpose of the present study was to evaluate the prevalence of parent reported sleep concerns in survivors of pediatric cancer, as well as evaluate the relationship between sleep and neurobehavioral functioning utilizing both parent and teacher input.

METHODS

The study included parent-teacher dyads of 75 survivors of pediatric cancer between the ages of six and 17 who completed a clinical neuropsychological evaluation with embedded measures of neurobehavioral functioning and sleep, including excessive daytime sleepiness and snoring. Bivariate correlations and multiple linear regressions were conducted to evaluate the relationship between sleep and neurobehavioral functioning.

RESULTS

No significant difference in parent reported sleep concerns was found with regard to demographic, diagnostic, or treatment variables. Daytime sleepiness was significantly elevated for 28% of the sample; snoring was not identified as a significant concern. Daytime sleepiness was significantly associated with worse neurobehavioral outcomes as reported by parents and teachers, including inattention, hyperactivity/impulsivity, peer difficulties, anxiety, depression, somatic complaints, and aggressive behaviors. Daytime sleepiness was not significantly related to report of learning problems.

CONCLUSIONS

Results further support that daytime sleepiness, as reported by parents, impacts approximately one third of survivors of pediatric cancer and is associated with worse neurobehavioral outcomes across home and school environments. As a result, it is vital that sleep functioning is a target of assessment in annual survivorship care. Future longitudinal studies are needed to further delineate the directionality of the sleep-neurobehavioral relationship in survivors.

Infant feeding practices and sleep at 1 year of age in the nationwide ELFE cohort

Sleep problems reported by parents affect 20% to 30% of infants. Few studies focused on the longitudinal association between infant feeding practices and sleep, especially in France. Analyses were based on 8,696 infants from the French national birth cohort ELFE. Collection of feeding practices from birth to 10 months allowed for the identification of trajectories of use of baby cereals and thickened formula by group‐based trajectory modelling and calculation of duration of any breastfeeding (BF) and age at complementary feeding introduction (CFI) excluding baby cereals. Total sleep duration (TSD), night waking (NW) and sleep onset difficulties (SOD) were reported at age 1. Associations between feeding and sleep were tested by multinomial logistic regressions. BF duration ≥6 months was associated with parent‐reported frequent NW, SOD and TSD ≤ 12 h/24 h at age 1. For TSD and SOD, this association was no longer significant after accounting for parental sleep‐related practices. Early use of baby cereals (≤5 months) was associated with poor sleep. Early CFI (<4 months) was associated with shorter TSD and SOD but not NW. Early use of thickened formula (only <6 months) was related to poor sleep at age 1 (NW and SOD), whereas late (around 6 months) use of thickened formula was associated with better sleep. BF duration ≥6 months was related to poor sleep at age 1 but not after adjustment on 1‐year parental sleep‐related practices except for NW. The use of baby cereals or early CFI was not related to better sleep at age 1.

Polygenic score for sleep duration. Association with cognition

STUDY OBJECTIVES

Age-related changes in sleep include a reduction in total sleep time and a greater incidence of sleep disorders, and are also an integral part of neurodegenerations. In the present study, we aimed to: a) identify common genetic variants that may influence self-reported sleep duration, and b) examine the association between the identified genetic variants and performance in different cognitive domains.

METHODS

A sample of 197 cognitively healthy participants, aged 20-80 years, mostly non-Hispanic Whites (69%), were selected from the Reference Abilities Neural Network and the Cognitive Reserve study. Each participant underwent an evaluation of sleep function and assessment of neuropsychological performance on global cognition and four different domains (memory, speed of processing, fluid reasoning, language). Published GWAS summary statistics from a Polygenic Score (PS) for sleep duration in a large European ancestry cohort (N = 30,251) were used to derive a PS in our study sample. Multivariate linear models were used to test the associations between the PS and sleep duration and cognitive performance. Age, sex, and education were used as covariates. Secondary analyses were conducted in three age-groups (young, middle, old).

RESULTS

Higher PS was linked to longer sleep duration and was also associated with better performance in global cognition, fluid reasoning, speed of processing, and language, but not memory. Results especially for fluid reasoning, language, and global cognition were driven mostly by the young group.

CONCLUSIONS

Our study replicated the previously reported association between sleep-PS and longer sleep duration. We additionally found a significant association between the sleep-PS and cognitive function. Our results suggest that common genetic variants may influence the link between sleep duration and cognitive health.

Poor Sleep Hygiene is Associated with Decreased Discrimination and Inattention on Continuous Performance Task in Doctor of Physical Therapy Students: A Cross-sectional Study

Introduction

Reduced sleep quality impairs learning, memory formation, attention, and executive function ability. Poor sleep quality or sleep hygiene has been shown to impair academic performance of undergraduate and medical students. The purpose of this study was to examine the association between sleep quality, sleep hygiene, and cognitive performance in Doctor of Physical Therapy (DPT) students.

Methods

Fifty DPT students at the University of Kansas Medical Center completed the Pittsburgh Sleep Quality Index (PSQI) and the Sleep Hygiene Index (SHI). Cognitive performance was assessed using the Continuous Performance Test (CPT) which is a test of sustained attention and the Trail-Making Task (TMT) to assess executive functioning. An actigraph was worn for one week to objectively characterize sleep outcomes. Spearman's correlations were performed to assess the association between self-report sleep quality, sleep hygiene, and outcomes on the cognitive tasks. Post-hoc Mann-Whitney and Kruskal-Wallis tests were conducted to examine group differences between sleep outcomes and cognitive performance for demographic variable categories.

Results

Twenty-three students (46%) reported poor sleep quality, and 27 participants (54%) had objectively-reported poor sleep quality. There was a significant positive correlation between SHI and Detectability (r_s= 0.297, p= 0.036) and Omissions (r_s=.343, p=0.015). There were group differences between sex and number of pets on the CPT outcomes, and there was a significant group difference between the number of drinks/week categories on the SHI.

Discussion and Conclusions

About half of the participants were identified as having poor sleep quality. Poorer sleep hygiene was associated with poorer discrimination and inattention, which could potentially impact the students' academic and clinical performance as well as their health and wellbeing. Also, certain demographic variables may modulate the results.

Sleep patterns and sleep deprivation recorded by actigraphy in 4th-grade and 5th-grade students

OBJECTIVE

This study investigates sleep patterns of fourth- and fifth-grade students using actigraphy.

METHODS

The study included 257 students enrolled in a Southwestern US school district who participated in a novel sleep science curriculum during the Spring 2016-17 and Fall 2017-18 semesters and met the study inclusion criteria. As part of this curriculum, participants underwent 5-7 days of continuous wrist actigraphy and completed an online sleep diary.

RESULTS

Approximately two-thirds of the 9-11-year-old fourth- and fifth-grade students slept less than the minimum 9 h per night recommended by both the American Academy of Sleep Medicine/Sleep Research Society and the National Sleep Foundation. The sleep midpoint time on weekends was about 1 h later than on weekdays. There was a significant effect of age on sleep duration. Compared to 9-year old students, a larger proportion of 10-year old students had a sleep duration less than 8.5 h. Boys had shorter sleep duration than girls, and a larger percentage of boys obtained less than 9 h of sleep compared to girls.

CONCLUSIONS

Insufficient sleep is a highly prevalent condition among 9-11-year-old fourth- and fifth-grade elementary students. Importantly, there is a difference between sleep patterns on weekdays and weekends which may portend greater problems with sleep in adolescence and young adulthood.

L-Tryptophan As Treatment for Pediatric Non-Rapid Eye Movement Parasomnia

OBJECTIVE

Parasomnias are common in childhood but there is no established treatment for parasomnias. The aim of this study was to (1) report on the outcome of using L-tryptophan to manage parasomnias in children and (2) examine sleep architecture and subjective psychological/sleep symptoms in children with parasomnia.

METHOD

A retrospective analysis was conducted of charts of children (3-18 years old) who underwent polysomnographic testing and were diagnosed with primary parasomnia. Study patients were either prescribed L-tryptophan (daily dose range: 500-4500 mg, mean dose of 2400 mg) to manage their parasomnias or administered no treatment whereby parents/guardians declined treatment. Questionnaires assessing sleep and psychosocial symptoms were administered at the initial clinical consultation and a follow-up parasomnia outcome questionnaire was administered over the phone to parents/guardians.

RESULTS

One hundred and sixty-five children (106 boys, 59 girls) received a sleep diagnosis of primary parasomnia. A significantly (p < 0.001) higher proportion (84%) of children taking L-tryptophan experienced improvements in their parasomnia symptoms compared with those (47%) who chose not to use L-tryptophan. Polysomnography revealed that children with parasomnias had an altered sleep architecture based on age-related normative values. Children with a diagnosis of parasomnia were also subjectively more fatigued and endorsed more depressive symptoms.

CONCLUSIONS

This study finds that parasomnias in children are not benign and that treatment with L-tryptophan provides a favorable outcome. Children diagnosed with parasomnia had altered sleep architecture, were more fatigued, and endorsed depressive symptoms. This study supports the need to diagnose and treat parasomnias in children.

Circadian ontogeny through the lens of nonparametric variables of actigraphy

Studies focusing on human rhythmicity show that human circadian rhythm suffers constant changes across lifespan. Changes in rest-activity patterns can be studied through nonparametric variables of actigraphy: L5 (an individual's least active 5 h), M10 (an individual's most active 10 h) and RA (relative amplitude of the rest-activity rhythm). The variable RA is the normalized difference between L5 and M10 - the higher the RA, the greater the difference between these two variables. This study used the data bank of the Human Chronobiology Laboratory of Federal University of Paraná (Brazil). It analyzed actimetric data of 93 children between 4 and 11 years of age in their naturalistic context in order to describe the development of nonparametric variables. Correlation between age and L5 was significantly negative (rho = - 0.29, p = 0.004), while correlation between age and RA was significantly positive (rho = 0.31, p = 0.003). The variables M10, sL5 (start of L5) and sM10 (start of M10) did not show significant correlation to age. Furthermore, there were no statistical differences between genders. The population of this study, healthy children, has been poorly assessed by similar literature. Through our results, we have demonstrated that, as children age, L5 significantly decreases, which reflects a smaller fragmentation of circadian rhythm. As an expected consequence, RA significantly increases. In other words, these nonparametric variables of actimetry successfully demonstrate that children tend to reduce nocturnal activity as they age, a phenomenon that reflects the ongoing consolidation of circadian rhythm.

Sleep Difficulties in Infancy Are Associated with Symptoms of Inattention and Hyperactivity at the Age of 5 Years: A Longitudinal Study

OBJECTIVE

Sleep difficulties are associated with cognitive and behavioral problems in childhood. However, it is still unclear whether early sleep difficulties are related to later development. We studied whether parent-reported sleep duration, night awakenings, and parent-reported sleep problems in early childhood are associated with symptoms of inattention and hyperactivity at the age of 5 years.

METHOD

Our study is based on the Child-Sleep birth cohort initially comprising 1673 families, of which 713 were retained at the age of 5 years. We used the Brief Infant Sleep Questionnaire and the Infant Sleep Questionnaire, which were filled out by the parents when their child was 3, 8, and 24 months and 5 years old. Symptoms of inattention and hyperactivity at the age of 5 years were assessed using the Strengths and Difficulties Questionnaire and the Five-to-Fifteen questionnaire.

RESULTS

Sleep duration at the age of 3, 8, and 24 months was associated with inattentiveness at 5 years of age. Moreover, parent-reported sleep problems at the age of 24 months were related to both inattentive and hyperactive symptoms at the age of 5 years. Finally, at the age of 5 years, parent-reported sleep problems and night awakenings were associated with concurrent symptoms of inattention and hyperactivity.

CONCLUSION

Our findings suggest that certain sleep characteristics related to sleep quality and quantity in early childhood are associated with inattentiveness and hyperactivity at the age of 5 years. Interestingly, sleep duration in early childhood is consistently related to inattention at the age of 5 years.

Personalized Sleep Parameters Estimation from Actigraphy: A Machine Learning Approach

BACKGROUND

The current gold standard for measuring sleep is polysomnography (PSG), but it can be obtrusive and costly. Actigraphy is a relatively low-cost and unobtrusive alternative to PSG. Of particular interest in measuring sleep from actigraphy is prediction of sleep-wake states. Current literature on prediction of sleep-wake states from actigraphy consists of methods that use population data, which we call generalized models. However, accounting for variability of sleep patterns across individuals calls for personalized models of sleep-wake states prediction that could be potentially better suited to individual-level data and yield more accurate estimation of sleep.

PURPOSE

To investigate the validity of developing personalized machine learning models, trained and tested on individual-level actigraphy data, for improved prediction of sleep-wake states and reliable estimation of nightly sleep parameters.

PARTICIPANTS AND METHODS

We used a dataset including 54 participants and systematically trained and tested 5 different personalized machine learning models as well as their generalized counterparts. We evaluated model performance compared to concurrent PSG through extensive machine learning experiments and statistical analyses.

RESULTS

Our experiments show the superiority of personalized models over their generalized counterparts in estimating PSG-derived sleep parameters. Personalized models of regularized logistic regression, random forest, adaptive boosting, and extreme gradient boosting achieve estimates of total sleep time, wake after sleep onset, sleep efficiency, and number of awakenings that are closer to those obtained by PSG, in absolute difference, than the same estimates from their generalized counterparts. We further show that the difference between estimates of sleep parameters obtained by personalized models and those of PSG is statistically non-significant.

CONCLUSION

Personalized machine learning models of sleep-wake states outperform their generalized counterparts in terms of estimating sleep parameters and are indistinguishable from PSG labeled sleep-wake states. Personalized machine learning models can be used in actigraphy studies of sleep health and potentially screening for some sleep disorders.

Effects of the environment of a simulated shelter in a gymnasium on sleep in children

Effects of the environment of a simulated shelter in a gymnasium on sleep were investigated in 20 healthy school-aged children. Measurements were obtained during a one-night stay in a school gymnasium during the summer (C). Activity levels were monitored using a wrist actigraph, and temperature and humidity of the bedrooms in the subjects' homes were monitored from 3 days before to 3 days after C. The subjects were asked to provide information regarding subjective sleep estimations and thermal sensations. The results for the days before C (BC), C, the first day after C (A1), and the second day after C (A2) were compared. The bedroom temperature was significantly lower on BC than on the other nights. No significant difference was observed in bedtime, whereas wake-up time was significantly earlier on C and later on A1 than on the other nights. Total sleep time was significantly decreased on C (3.6 h) and increased on A1 when compared to the other nights. Daytime nap was significantly increased on A1 when compared to the other days. Subjective estimation of sleep quality was decreased and sweat sensation before sleep was increased on C when compared to the other nights. The main reason for sleep disturbances on C was heat. These results indicate that the environment of the simulated shelter in the gymnasium severely disturbed sleep in children. The resulting loss of sleep was compensated for by increased nocturnal sleep time and daytime napping on the next day.

Sparse multiple factor analysis to integrate genetic data, neuroimaging features, and attention-deficit/hyperactivity disorder domains

OBJECTIVES

We proposed the application of a multivariate cross-sectional framework based on a combination of a variable selection method and a multiple factor analysis (MFA) in order to identify complex meaningful biological signals related to attention-deficit/hyperactivity disorder (ADHD) symptoms and hyperactivity/inattention domains.

METHODS

The study included 135 children from the general population with genomic and neuroimaging data. ADHD symptoms were assessed using a questionnaire based on ADHD-DSM-IV criteria. In all analyses, the raw sum scores of the hyperactivity and inattention domains and total ADHD were used. The analytical framework comprised two steps. First, zero-inflated negative binomial linear model via penalized maximum likelihood (LASSO-ZINB) was performed. Second, the most predictive features obtained with LASSO-ZINB were used as input for the MFA.

RESULTS

We observed significant relationships between ADHD symptoms and hyperactivity and inattention domains with white matter, gray matter regions, and cerebellum, as well as with loci within chromosome 1.

CONCLUSIONS

Multivariate methods can be used to advance the neurobiological characterization of complex diseases, improving the statistical power with respect to univariate methods, allowing the identification of meaningful biological signals in Imaging Genetic studies.

Night sleep duration trajectories and associated factors among preschool children from the EDEN cohort

OBJECTIVE

Sleep duration may vary both interindividually and intraindividually over time. We aimed to identify night-sleep duration (NSD) trajectories among preschoolers and to study associated factors.

METHODS

NSD was collected within the French birth-cohort study EDEN at ages 2, 3, and 5-6 years through parental questionnaires, and were used to model NSD trajectories among 1205 children. Familial socioeconomic factors, maternal sociodemographic, health and lifestyle characteristics, as well as child health, lifestyle, and sleep characteristics at birth and/or at age two years were investigated in association with NSD using multinomial logistic regressions.

RESULTS

Five distinct NSD trajectories were identified: short (SS, <10 h, 4.9%), medium-low (MLS, <11 h, 47.8%), medium-high (MHS, ≈11.5 h, 37.2%), long (LS, ≥11.5 h, 4.5%) and changing (CS, ie, ≥11.5 h then <11 h, 5.6%) NSD trajectories. Multivariable analyses showed in particular that compared to the MHS trajectory factors associated with increased risk for the SS trajectory were male gender, first child, maternal age and working status, night-waking, parental presence when falling asleep, television-viewing duration, as well as both "Processed and fast foods" and the "Baby food" dietary patterns at age two years. Factors positively associated with the CS trajectory were maternal smoking, feeding at night, and the Processed and fast foods dietary pattern at age two years, whereas child's activity and emotionality scores at age one year were negatively associated.

CONCLUSION

We identified distinct NSD trajectories among preschoolers and associated early life factors. Some of them may reflect less healthy lifestyles, providing cues for early multi-behavioral prevention interventions.

Prevalence of attention-deficit/hyperactivity disorder symptoms and their associations with sleep schedules and sleep-related problems among preschoolers in mainland China

Background

Attention-deficit/hyperactivity disorder (ADHD) among children is an increasing public health concern. The identification of behavioral risk factors, including sleep quality, has important public health implications for prioritizing behavioral intervention strategies for ADHD. Herein, this study aimed to investigate the prevalence of high levels of ADHD symptoms and to explore the association between sleep schedules, sleep-related problems and ADHD symptoms among preschoolers aged 3 to 6 years in mainland China.

Methods

A cross-sectional study was conducted, comprising a large sample of 15,291 preschoolers in Ma’anshan city of Anhui Province in China. ADHD symptoms were assessed by the 10-item Chinese version of the Conners Abbreviated Symptom Questionnaire (C-ASQ). Sleep-related variables included caregivers’ responses to specific questions addressing children’s daytime and nighttime sleep schedules, as well as sleep-related behaviors. Data on other factors were also collected, such as socio-demographic characteristics, TV viewing duration on weekdays and weekends, and outdoor activities. Logistic regression models were used to analyze the relationships between sleep schedules, sleep-related problems and ADHD symptoms.

Results

Approximately 8.6% of the total sample of preschoolers had high levels of ADHD symptoms, with boys having higher levels than girls (9.9% vs. 7.2%). In the logistic regression analysis, after adjusting for TV viewing duration, outdoor activities, and socio-demographic characteristics, delayed bedtime was significantly associated with a risk of high levels of ADHD symptoms, with odds ratios (OR) of 2.50 [95% confidence interval (CI): 2.09 ~ 3.00] and 2.04 (95% CI: 1.72 ~ 2.42) for weekdays and weekends, respectively. Longer time falling asleep (≥ 31 min) (OR = 1.76, 95% CI: 1.47 ~ 2.11), no naps (OR = 1.57, 95% CI: 1.34 ~ 1.84) and frequent sleep-related problems (OR = 4.57, 95% CI: 3.86 ~ 5.41) were also significantly associated with an increased risk of high levels of ADHD symptoms, while longer sleep duration (> 8.5 h) was associated with a decreased risk of high levels of ADHD symptoms (OR = 0.76, 95% CI: 0.67~ 0.87).

Conclusions

ADHD symptoms are prevalent in preschoolers in Ma’anshan region, China. Undesirable sleep schedules and sleep-related problems among preschoolers confer a risk of ADHD symptoms, highlighting the finding that beneficial and regular sleep habits potentially attenuate ADHD symptoms among preschoolers.

Relationships Between Smoking and Sleep Problems in Black and White Adolescents

Study Objectives

The relationship between sleeping and smoking during adolescence remains unclear and is likely complex. We aim to evaluate the longitudinal reciprocal associations between sleep problems, sleep duration, and smoking among non-Hispanic white (NHW) and non-Hispanic black (NHB) youth.

Design

Prospective cohort study.

Setting

NEXT Generation Health Study.

Participants

A national sample (N = 1394) of NHB and NHW 10th graders were surveyed annually between 2009 (Wave 1) and 2012 (Wave 3).

Interventions

N/A.

Measurements and Results

Past 30-day smoking, chronic difficulty falling asleep, recent difficulty falling asleep, difficulty staying asleep, and weekday and weekend sleep duration were measured at each wave. Using structural equation models, we observed significant autocorrelations over time for sleep problems and sleep duration. We found significant reciprocal, prospective relationships between smoking and sleep problems. The strengths of the relationships differed by race, with a stronger association between sleep problems and subsequent smoking for NHB than NHW youth. Conversely, a stronger association between smoking and subsequent sleep problems for NHW than NHB youth was observed. These association were independent of demographics, snoring or sleep apnea, body mass index, depressive symptoms, alcohol use, and soda consumption.

Conclusions

Reciprocal and prospective relationships exist for youth smoking and sleep problems and duration in both NHW and NHB youth. Further research is needed to unravel the complex relationship between the direct effects of nicotine, lifestyle choices that may link smoking and sleep problems, and racial differences.

Child Executive Control as a Moderator of the Longitudinal Association Between Sleep Problems and Subsequent Attention-Deficit/Hyperactivity Disorder Symptoms

Objective

To examine the longitudinal associations among sleep, executive control (EC), and attention-deficit/hyperactivity disorder (ADHD) symptoms in childhood.

Methods

In this longitudinal study (N = 271), parents answered questions about sleep problems when children were 3 years old, children completed a comprehensive EC task battery at 4.5 years, and teachers completed standardized measures of child ADHD symptoms in 4th grade.

Results

Latent moderated structural equation models demonstrated that sleep problems at 3 years and EC deficits at 4.5 years were associated with ADHD symptoms in 4th grade. EC moderated the relationship between sleep problems and hyperactivity/impulsivity, such that children with both sleep problems and poor EC were particularly at risk for hyperactivity/impulsivity.

Conclusions

Sleep problems and EC deficits early in development were associated with increased risk for ADHD symptoms in elementary school. Early assessment and intervention to promote healthy sleep and EC development may be helpful in ADHD prevention.

Sleep Duration, Snoring Prevalence, Obesity, and Behavioral Problems in a Large Cohort of Primary School Students in Japan

Study Objectives

Poor or short sleep and the presence of snoring indicative of sleep-disordered breathing (SDB) have been associated with behavioral problems in school-aged children. We examined the relationship between SDB, sleep duration, obesity risk, and behavioral characteristics in Japanese elementary school students using a large-scale survey.

Methods

We conducted a cross-sectional study of children enrolled in all 46 public primary schools in Matsuyama city, Japan. The children's parents or guardians completed a questionnaire that covered sleep habits, presence of SDB risk, and behavioral characteristics.

Results

In total, 24 296 responses were received (90% response rate). After excluding incomplete responses, we analyzed complete datasets for 17 769 children. Mean sleep duration decreased with age, as did the prevalence of pediatric SDB. We found an increased risk for the presence of SDB and short sleep among overweight/obese children. With SDB or short sleep, we observed significantly increased odds of restless behaviors, fidgety behaviors, and poor concentration in school.

Conclusions

Shorter sleep duration was associated with increased risk of obesity, and in turn, obesity increased SDB risk. Both short sleep duration and SDB risk were significantly associated with behavioral problems in school.

The Association between Sleep and Theory of Mind in School Aged Children with ADHD

Theory of Mind (ToM) is defined as the ability to infer a range of internal mental states of others, including beliefs, intentions, desires, and emotions. These abilities are associated with children’s ability to socialize effectively with peers. ToM impairments are associated with peer rejection and psychiatric disorders such as Attention-Deficit/Hyperactivity Disorder (ADHD). Previous studies have found poor sleep negatively impacts executive functioning (EF) and emotional information processing, which are essential for the effective use of ToM. Youth with ADHD have EF deficits and sleep problems. However, the relationship between sleep, executive functioning, and ToM in children with ADHD has not been studied. In this review, we propose that the poor social and interpersonal skills characterizing individuals with ADHD could be explained by the impact of poor sleep on the emotional and cognitive mechanisms underlying ToM.

Prospective Study of Insufficient Sleep and Neurobehavioral Functioning Among School-Age Children

OBJECTIVE

To examine associations between insufficient sleep and neurobehavioral functioning in childhood as reported by mothers and teachers.

METHODS

Participants were 1046 children in a prebirth cohort study. Main exposures were insufficient sleep durations at 3 time points: 6 months to 2 years, defined as sleep <11 h/d, 11 to <12 h/d (vs ≥12); 3 to 4 years, defined as sleep <10 h/d, 10 to <11 h/d (vs ≥11); and 5 to 7 years, sleep <9 h/d, 9 to <10 h/d (vs ≥10). Outcomes at age 7 years were executive function, behavior, and social-emotional functioning, assessed using the Behavioral Rating Inventory of Executive Function (BRIEF) and the Strengths and Difficulties Questionnaire (SDQ). Higher scores indicate poorer functioning. Mothers and teachers completed both instruments independently.

RESULTS

At age 7 years, mean (SD) mother and teacher report of the BRIEF global executive composite scale were 48.3 (7.9) and 50.7 (9.4) points, respectively, and of the SDQ total difficulties score was 6.5 (4.7) and 6.2 (5.7). In multivariable models, children who slept <10 h/d at 3 to 4 years had worse maternal-reported scores for the BRIEF (2.11 points; 95% confidence interval, 0.17-4.05) and SDQ (1.91 points; 95% confidence interval, 0.78-3.05) than those with age-appropriate sleep. Children who slept <9 h/d at 5 to 7 years also had worse scores. At both ages, associations with teacher-reported results were consistent with those of mothers. Infants who slept 11 to <12 h/d had higher teacher- but not mother-reported scores.

CONCLUSIONS

Insufficient sleep in the preschool and early school years is associated with poorer mother- and teacher-reported neurobehavioral processes in midchildhood.

Effects of Sleep Deprivation on Spatial Learning and Memory in Juvenile and Young Adult Rats

Sleepiness is commonly seen in adolescents and can negatively impact school performance. Little research has investigated the impact of sleepiness in juvenile animals on spatial learning. Sprague-Dawley juvenile (<30 days) and young adult (>60 days) rats were sleep deprived for 24 hours and tested, along with controls, in a water maze task. Sleep deprived juveniles were slower to learn the location of the hidden platform than controls; however, adult performance was not impaired. Sleep deprivation did not impair recall during a probe trial for either age group. Sleep deprivation prior to testing slowed spatial learning in juveniles but not adults.

Relationships Between Smoking and Sleep Problems in Black and White Adolescents

Study Objectives

The relationship between sleeping and smoking during adolescence remains unclear and is likely complex. We aim to evaluate the longitudinal reciprocal associations between sleep problems, sleep duration, and smoking among non-Hispanic white (NHW) and non-Hispanic black (NHB) youth.

Design

Prospective cohort study.

Setting

NEXT Generation Health Study.

Participants

A national sample (N = 1394) of NHB and NHW 10th graders were surveyed annually between 2009 (Wave 1) and 2012 (Wave 3).

Interventions

N/A.

Measurements and Results

Past 30-day smoking, chronic difficulty falling asleep, recent difficulty falling asleep, difficulty staying asleep, and weekday and weekend sleep duration were measured at each wave. Using structural equation models, we observed significant autocorrelations over time for sleep problems and sleep duration. We found significant reciprocal, prospective relationships between smoking and sleep problems. The strengths of the relationships differed by race, with a stronger association between sleep problems and subsequent smoking for NHB than NHW youth. Conversely, a stronger association between smoking and subsequent sleep problems for NHW than NHB youth was observed. These association were independent of demographics, snoring or sleep apnea, body mass index, depressive symptoms, alcohol use, and soda consumption.

Conclusions

Reciprocal and prospective relationships exist for youth smoking and sleep problems and duration in both NHW and NHB youth. Further research is needed to unravel the complex relationship between the direct effects of nicotine, lifestyle choices that may link smoking and sleep problems, and racial differences.

Attention-deficit hyperactivity disorder symptoms add risk to circadian rhythm sleep problems in depression and anxiety

BACKGROUND

Comorbid ADHD symptoms may partly account for circadian rhythm disturbances in depression and anxiety disorders.

METHODS

Self-reported sleep characteristics of 2090 participants in the Netherlands Study of Depression and Anxiety were assessed using the Munich Chronotype Questionnaire. We defined 3 groups: healthy controls (HC), persons with lifetime depression and/or anxiety disorders (LDA), and those with both LDA and high ADHD symptoms (LDA+ADHD), using the Conner's Adult ADHD Rating Scale.

RESULTS

Sleep characteristics were least favorable in the LDA+ADHD group. Important group differences between LDA+ADHD, LDA and HC were found for extremely late chronotype (12% vs. 5% vs. 3%; p<.001), sleep duration <6h (15% vs. 5% vs. 4%; p<.001), and for an indication of the Delayed Sleep Phase Syndrome (DSPS; 16% vs. 8% vs. 5%; p<.001). After adjustment for covariates, including depression and anxiety, presence of ADHD symptoms increased the odds ratio for late chronotype (OR=2.6; p=.003), indication of DSPS (OR=2.4; p=.002), and sleep duration <6h (OR=2.7; p=.007).

LIMITATIONS

ADHD conceptually overlaps with symptom presentation of depression and anxiety. We used a cross-sectional study design, and used self reported sleep characteristics.

CONCLUSIONS

High ADHD symptoms were associated with an increased rate of circadian rhythm sleep disturbances in an already at-risk population of people with depression and/or anxiety disorders. Circadian rhythm sleep disorders, as often seen in ADHD are not entirely due to any comorbid depression and/or anxiety disorder. Adequate treatment of such sleep problems is needed and may prevent serious health conditions in the long term.

Changes in sleep duration in Spanish children aged 2-14 years from 1987 to 2011

OBJECTIVE

Historical decreases in sleep duration in children have been documented worldwide; however, there is sparse information on sleep duration in differing cultural regions. We assess sleep duration and its trends for children in Spain from 1987 to 2011 and associated sociodemographic characteristics.

METHODS

Data from eight Spanish National Health Surveys, from 1987 to 2011, were collected on parent-reported sleep duration and associated socio-demographic characteristics including age, sex, parental level of education, child body mass index (BMI), and physical activity. A total of 24,867 children aged 2-14 years were included in the final sample.

RESULTS

Overall, short sleep duration increased to 44.7% from 29.8% in 1987. Decreasing sleep duration trends were found in all demographic groups, decreasing by around 20 minutes in 24 hours from 1987 to 2011; decreasing to 10 hours 16 minutes in 2- to 5-year olds, 9 hours 31 minutes in 6- to 9-year-olds, and 8 hours 52 minutes in 10- to 14-year-olds. No difference in sleep duration was found between girls and boys. Sleep duration was associated with year of survey, age, level of parental education, obesity, and exercise.

CONCLUSIONS

Almost 45% of children in Spain are not sleeping the recommended amount. Regional differences in sleep attitudes and duration alongside a lack of consistency in cut-offs for age-appropriate ideal sleep in literature is a barrier for international comparison and highlights the need for research in physiological sleep requirements. With the association of short sleep duration with many different health outcomes, sleep should be considered as a modifiable lifestyle factor and a public health issue.

The Importance of Sleep: Attentional Problems in School-Aged Children With Down Syndrome and Williams Syndrome

In typically developing (TD) children, sleep problems have been associated with day-time attentional difficulties. Children with developmental disabilities often suffer with sleep and attention problems, yet their relationship is poorly understood. The present study investigated this association in school-aged children with Down syndrome (DS) and Williams syndrome (WS). Actigraphy and pulse oximetry assessed sleep and sleep-disordered breathing respectively, and attention was tested using a novel visual Continuous Performance Task (CPT).Attentional deficits were evident in both disorder groups. In the TD group, higher scores on the CPT were related to better sleep quality, higher oxyhemoglobin saturation (SpO2), and fewer desaturation events. Sleep quality, duration, and SpO2 variables were not related to CPT performance for children with DS and WS.

Less Efficient Neural Processing Related to Irregular Sleep and Less Sustained Attention in Toddlers

The current study used event-related potentials to examine a candidate process through which sleep difficulties affect attentional processing in toddlers. Fifteen toddlers participated in an auditory Oddball task while neurophysiological data were collected. Sleep deficits were assessed using actigraphs, and attention was examined with a sustained attention task. A P3-like component was elicited from the toddlers, and longer target P3 latencies were associated with poorer sustained attention and irregular sleep. Findings suggest that irregular sleep is associated with less efficient attentional processing as reflected by the P3 component, and that longer target P3 latencies are associated with poorer sustained attention.

Technology Use and Sleep Quality in Preadolescence and Adolescence

STUDY OBJECTIVES

The purpose of this study was to analyze differences between preadolescents and adolescents on the use of technology and to test the contribution of using Internet and mobile phone, and circadian preference on sleep quality.

METHODS

We recruited a sample of 850 (364 males) preadolescents and adolescents. Self-report questionnaires about sleep schedule, sleep wake behavior problems, circadian preferences, and the use of technology (e.g., Internet and mobile phone) were administered. Students were asked to fill out the School Sleep Habits Survey, a self-report questionnaire on the use of technology, the Mobile Phone Involvement Questionnaire (MPIQ), and the Shorter Promis Questionnaire (SPQ).

RESULTS

Adolescents reported more sleep problems, a tendency toward eveningness, and an increase of Internet and phone activities, as well as social network activities, while preadolescents were more involved in gaming console and television viewing. The regression analysis performed separately in the two age groups showed that sleep quality was affected by the circadian preference (eveningness) in both groups. Adolescents' bad sleep quality was consistently associated with the mobile phone use and number of devices in the bedroom, while in preadolescents, with Internet use and turning-off time.

CONCLUSIONS

The evening circadian preference, mobile phone and Internet use, numbers of other activities after 21:00, late turning off time, and number of devices in the bedroom have different negative influence on sleep quality in preadolescents and adolescents.

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

Early childhood represents a time of developmental changes in both sleep and self-regulation, a construct reflecting the ability to control one's behaviour, attention and emotions when challenged. Links between sleep and self-regulation processes have been proposed, but experimental evidence with young children is lacking. In the current study, we tested the effects of acute sleep restriction (nap deprivation) on toddlers' self-regulation. Healthy children (n = 12; four males; aged 30-36 months (33.9 ± 1.7)) slept on a strict schedule (verified with actigraphy and sleep diaries) for 5 days before each of two afternoon assessments following a nap and a no-nap condition (~11-day protocol). Children were videotaped while attempting an unsolvable puzzle, and 10 mutually exclusive self-regulation strategies were later coded. On average, children lost ~90 min of sleep on the no-nap versus the nap day. Nap deprivation resulted in moderate-to-large effects on self-regulation strategies, with decreases in scepticism (d = 0.77; 7% change), negative self-appraisal (d = 0.92; 5% change) and increases in physical self-soothing (d = 0.68; 10% change), focus on the puzzle piece that would not fit (perseveration; d = 0.50; 9% change) and insistence on completing the unsolvable puzzle (d = 0.91; 10% change). Results suggest that sleep serves an important role in the way that toddlers respond to challenging events in their daily lives. After losing daytime sleep, toddlers were less able to engage effectively in a difficult task and reverted to less mature self-regulation strategies than when they were well rested. Over time, chronically missed sleep may impair young children's self-regulation abilities, resulting in risk for social-emotional, behavioural and school problems.

Attention deficit hyperactivity disorder symptomatology and pediatric obesity: Psychopathology or sleep deprivation?

The relationship between attention deficit hyperactivity disorder (ADHD) and obesity in children has received considerable attention in recent years. However, the literature currently overlooks the potential causal and maintaining role that sleep problems may play in this relationship. Using a biopsychosocial framework, this article highlights how sleep problems impact the biological, psychological, and social aspects of both ADHD symptomatology and obesity. An in-depth examination of this model illustrates the imperative need for future research and clinical practice to recognize and explore the role sleep has in the link between obesity and ADHD symptomatology.

Associations of sleep disturbance with ADHD: implications for treatment

Attention-deficit/hyperactivity disorder (ADHD) is commonly associated with disordered or disturbed sleep. The relationships of ADHD with sleep problems, psychiatric comorbidities and medications are complex and multidirectional. Evidence from published studies comparing sleep in individuals with ADHD with typically developing controls is most concordant for associations of ADHD with: hypopnea/apnea and peripheral limb movements in sleep or nocturnal motricity in polysomnographic studies; increased sleep onset latency and shorter sleep time in actigraphic studies; and bedtime resistance, difficulty with morning awakenings, sleep onset difficulties, sleep-disordered breathing, night awakenings and daytime sleepiness in subjective studies. ADHD is also frequently coincident with sleep disorders (obstructive sleep apnea, peripheral limb movement disorder, restless legs syndrome and circadian-rhythm sleep disorders). Psychostimulant medications are associated with disrupted or disturbed sleep, but also ‘paradoxically’ calm some patients with ADHD for sleep by alleviating their symptoms. Long-acting formulations may have insufficient duration of action, leading to symptom rebound at bedtime. Current guidelines recommend assessment of sleep disturbance during evaluation of ADHD, and before initiation of pharmacotherapy, with healthy sleep practices the first-line option for addressing sleep problems. This review aims to provide a comprehensive overview of the relationships between ADHD and sleep, and presents a conceptual model of the modes of interaction: ADHD may cause sleep problems as an intrinsic feature of the disorder; sleep problems may cause or mimic ADHD; ADHD and sleep problems may interact, with reciprocal causation and possible involvement of comorbidity; and ADHD and sleep problems may share a common underlying neurological etiology.

Sleep environments and sleep durations in a sample of low-income preschool children

STUDY OBJECTIVES

Sleep duration is commonly studied in children, but less is known about the potential impact of adverse sleep environments, particularly at preschool ages. We examined the frequency of suboptimal sleep environments and tested for associations with sleep duration or nocturnal sleep time among low-income preschool children.

METHODS

Parents of Head Start preschoolers in Michigan (Detroit and greater Lansing) completed questionnaires on children's sleep schedules and sleep environments. Respondents indicated how often their children slept in a place "too bright," "too loud," "too cold," or "too hot" on a scale of 1 = never to 5 = always. A suboptimal sleep environment (SSE) was defined when one or more of these conditions were reported for ≥ 1-2 nights/week. Weeknight sleep duration or reported time that the child went to sleep was regressed on SSE as an explanatory variable, with adjustment for age, race/ethnicity, gender, maternal education, and average daily nap duration.

RESULTS

Among 133 preschool children, mean age was 4.1 ± 0.5 (SD), 48% were male, 39% were white, and 52% were black; 34% of parents had ≤ a high school degree. Parents reported that 26 (20%) of the children slept in a SSE ≥ 1-2 nights per week. In regression models, SSE was associated with 27 minutes shorter sleep duration (β = -0.45, SE = 0.22, p = 0.044) and 22 minutes later time child "fell asleep" (β = 0.37, SE = 0.19, p = 0.048) on weeknights.

CONCLUSIONS

Among these Head Start preschool children, environmental challenges to adequate sleep are not uncommon, and they may have consequences. Clinician or preschool assessment of sleep environments may open opportunities to improve sleep at early ages.

CITATION

Wilson KE; Miller AL; Lumeng JC; Chervin RD. Sleep environments and sleep durations in a sample of low-income preschool children.