High incidence of sleep problems in children with developmental disorders: results of a questionnaire survey in a Japanese elementary school

Associations between sleep problems in children with ADHD and parental insomnia and ADHD symptoms

Sleep problems are common in children with attention deficit hyperactivity disorder (ADHD). Children's sleep problem may influence, and be influenced by, parents' sleep problems as well as parents' ADHD symptoms. In the current study we examined the associations of parent-rated sleep quality and sleep timing of pre-adolescent children with parental insomnia symptoms, parental ADHD symptoms and dysfunctional attitudes and beliefs about sleep in a convenience sample recruited by advertisement (N = 120). Childhood sleep problems were common in the sample, with 82% of children exceeding the threshold for the presence of a paediatric sleep disorder. Children's sleep quality showed minimal association with their sleep timing and chronotype. Parental insomnia symptoms, ADHD symptoms and dysfunctional beliefs and attitudes about sleep all associated with their children's sleep quality, and with the sleep subdomains of sleep anxiety and parasomnias. In multiple regression analysis only parental insomnia score was a significant predictor of children's sleep quality. Children's bedtimes, wake times, sleep duration, chronotype or social jetlag did not associate with parents' ADHD or insomnia symptoms. Sleep quality was significantly poorer in children whose parents scored as both consistent for adult ADHD and probable for insomnia disorder compared to parents who scored as either ADHD consistent or insomnia probable, or those who parents scored as neither. We discuss the putative nature of the relationships between sleep quality of children with ADHD and parental ADHD and insomnia symptoms, and suggest that clinicians consider parental sleep when attending to children with ADHD.

"Tell Me More About Your Child's Sleep": A Qualitative Investigation Of Sleep Problems In Children With ADHD

OBJECTIVE

To investigate parental experiences and perceptions of sleep problems in their children with Attention Deficit Hyperactivity Disorder (ADHD), the perceived impacts of sleep problems and coping strategies deployed by parents.

METHODS

Semi-structured interviews with twenty-six parents of pre-adolescent children with a diagnosis of ADHD, followed by thematic analysis of the interview transcripts.

RESULTS

Three themes were generated from the data: Children's Sleep Difficulties; Impacts of Children's Sleep; and Improving Children's Sleep. Sleep initiation problems in children with ADHD were commonly reported by parents, were perceived to be linked in a bidirectional manner with executive and emotional problems, and were reported as being disruptive to parental sleep. Some parents reported that their children's sleep problems were the initial prompt that lead to a diagnosis of ADHD. Parents reported utilizing a range of coping strategies to mitigate sleep problems, such as controlling the bedroom sensory environment and using emotional "wind down" as part of the bedtime routine. Some parents endorsed a beneficial effect of melatonin on their children's sleep.

CONCLUSIONS

Sleep problems in children with ADHD were perceived as important issues by parents. Equipping parents with evidence-based strategies for the management of their children's sleep may lead to benefits for the children, parents and wider household.

Pediatrician and parental evaluation of child neurodevelopment at 2 years of age

BACKGROUND

The early identification of infants with a risk for neurodevelopmental disorders in the first few years of life is essential for better developmental outcomes. Screenings should be carried out by combining the family pediatricians' and parents' perspectives, the two fundamental sources of information on children's health. The present study has three aims: (a) to test the feasibility of parent-report instruments to detect warning signs in their children's development; (b) to ascertain whether there is an agreement between the family pediatricians' (FP) clinical judgments of warning signs and the parental perceptions; (c) to determine whether there is a link between parents' distress and child development.

METHODS

Within the NASCITA birth cohort, in addition to the family pediatrician's clinical evaluation with routine tools, the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) was completed by parents to assess the child's language, social skills, behavior, and sensory areas. Parents were also asked to complete the Parenting Stress Index, Short Form (PSI-SF) to verify the magnitude of stress in the parent-child system. Univariate and multivariate analyses were performed to evaluate the association between child and parental characteristics and the presence of warning signs.

RESULTS

The follow-up assessment was completed for 435 infants: 69 (15.8%) presented warning signs: 43 in the pediatrician's assessment and 36 in the M-CHAT-R (10 in both). A total of 16 children (14 with warning signs) received a diagnosis after a specialist evaluation. Being male (OR 2.46, 95%CI: 1.23-4.91) and having sleep disorders (OR 2.43, 95% CI 1.17-5.04) was associated with a greater likelihood of warning signs in the multivariate analysis, while reading aloud was a protective factor (not exposed versus exposed (OR = 3.14; 95% CI 1.60-6.17). For 73 children (18.4%), at least one parent tested positive for PSI-SF. An increased prevalence of parental distress was observed in children with warning signs (OR 2.36, 95% CI 1.27-4.37).

CONCLUSIONS

Integrating physician and parental perspectives during well-child visits and in clinical practice appears feasible and can improve the identification of children at risk of developmental disorders.

Factors associated with sleep disorders among adolescent students in rural areas of China

Background

This study aimed to determine sleep patterns and the prevalence and association factors of sleep disorders in a regionally representative sample in Mo Jiang, China.

Methods

A total of 2,346 (participation rate 93.5%) Grade 7 students (aged 13-14 years) from 10 middle schools, including 1,213 (51.7%) boys and 1,133 (48.3%) girls, participated in the study. All the participants were invited to complete questionnaires that acquired information on sleep patterns, academic performance, academic stress, and sociodemographic factors. Sleep disorders were assessed using the Chinese version of the Children's Sleep Habits Questionnaire. Logistic regression models were used to investigate factors associated with sleep disorders.

Results

The prevalence of sleep disorders among rural adolescents was 76.4%, which is higher than that among urban adolescents. Compared with previous findings in urban areas, our results indicate that sleep loss is much more severe in rural adolescents. Sleep disorders were positively associated with factors, such as watching TV [odds ratio (OR) = 1.22, p = 0.001], academic performance (OR = 1.80, p < 0.001), and academic stress (OR = 1.38, p = 0.04). In addition, girls were more likely to suffer from sleep disorders than boys (OR = 1.36, p = 0.01).

Conclusion

Insufficient sleep and sleep disorders have become common health problems in rural Chinese adolescents.

The Japanese version of the children's sleep habits questionnaire (CSHQ-J): A validation study and influencing factors

SUBJECT

This study aimed to validate the Japanese version of the Child's Sleep Habits Questionnaire (CSHQ-J) and identify which factors affect the CHSQ-J total score.

METHODS

The participants were 3158 children (aged 4-12 years) and their parent/guardian, as community samples from large, medium-sized, and small cities. Each parent/guardian filled in the questionnaire set (CSHQ-J, Pittsburgh Sleep Quality Index, demographic data: family structure, sleep environment, participants' present illness, and economic information); we also collected 51 clinical samples from our facility to calculate the cutoff score. According to the age of the participants in the original CSHQ (4-10 years), validation was assessed statistically via exploratory and confirmatory factor analyses and internal consistency (verified by Cronbach's α). Multivariate analysis was conducted to identify factors affecting the CSHQ-J total score.

RESULTS

We received responses from 2687 participants (response rate: 85%) and analyzed 1688 participants who were the age of the original CSHQ participants. The alpha coefficients of each subscale of the CSHQ-J ranged from 0.43 to 0.68. The cutoff score was 48 (sensitivity: 0.69, specificity: 0.79). The confirmatory and exploratory factor analyses did not converge. Multivariate analysis showed that the factors that significantly influenced the CSHQ-J total score were co-sleeping, supplemental sleep, and child's age. Present illness, especially adenoids, also significantly influenced CSHQ total score.

CONCLUSIONS

The CSHQ-J has adequate internal consistency and is useful for screening for pediatric sleep disorders. Supplemental sleep, habit of co-sleeping, and child's age should be considered when using the CSHQ-J as a screening tool for sleep problems in children.

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.

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.

Attention-deficit/hyperactivity disorder symptoms and sleep problems in preschool children: the role of autistic traits

BACKGROUND

Sleep problems are elevated in children with attention-deficit/hyperactivity disorder (ADHD). However, until now there has been comparatively little research on the role of autistic traits in this association. The current study examined the association between ADHD symptoms and sleep problems in Japanese preschool children and whether autistic traits might also be important for this relationship.

METHODS

Data were analyzed from 1053 children (average age 64.14 months, range 58-71; 50.3% male) that were drawn from the Tama Children's Survey (TCS). Parent-reported information was obtained on ADHD symptoms using the Strengths and Difficulties Questionnaire (SDQ) and autistic traits with the Social Responsiveness Scale Second Edition (SRS-2). Parents also provided information on three different categories of sleep problems experienced by their children - parasomnias, sleep disordered breathing and awakening/daytime problems. Ordinal logistic regression analysis was used to examine the associations.

RESULTS

In analyses adjusted for sociodemographic factors, the mother's mental health and child's emotional problems, compared to children with no ADHD symptoms or autistic traits, children with only ADHD symptoms had significantly increased odds for only one of 11 individual sleep problems - waking in a negative mood. In contrast, children with comorbid ADHD symptoms and autistic traits had elevated odds for five sleep problems with odds ratios ranging from 2.10 (takes time to become alert in the morning) to 3.46 (excessive body movement while sleeping).

CONCLUSIONS

Sleep problems may be especially elevated in children with comorbid ADHD symptoms and autistic traits.

Disorders of Arousal: A Chronobiological Perspective

Non-rapid eye movement (NREM) sleep parasomnias are characterized by motor and emotional behaviors emerging from incomplete arousals from NREM sleep and they are currently referred to as disorders of arousal (DoA). Three main clinical entities are recognized, namely confusional arousal, sleep terror and sleepwalking. DoA are largely present in pediatric populations, an age in which they are considered as transitory, unhabitual physiological events. The literature background in the last twenty years has extensively shown that DoA can persist in adulthood in predisposed individuals or even appear de novo in some cases. Even though some episodes may arise from stage 2 of sleep, most DoA occur during slow wave sleep (SWS), and particularly during the first two sleep cycles. The reasons for this timing are linked to the intrinsic structure of SWS and with the possible influence on this sleep phase of predisposing, priming and precipitating factors for DoA episodes. The objective of this paper is to review the intrinsic sleep-related features and chronobiological aspects affecting SWS, responsible for the occurrence of the majority of DoA episodes during the first part of the night.

Association between children's sleep patterns and problematic behaviors at age 5

BACKGROUND

Night-shift lifestyles affect children as well as adults, and are associated with sleep and behavioral problems among children. This study aimed to investigate associations among sleep patterns, individual/environmental factors, and problematic behaviors in children at age 5 years.

METHODS

Data for sleep patterns, individual / environmental factors, and problematic behaviors for 8,689 5-year-old children were collected from health-checkup records. Problematic behaviors investigated were anxious behavior (being afraid, difficulty being separated from the mother), developmental behavior (violence, restlessness, rebellious behavior, restrictive diet, stereotypic play), personal habits (thumb-sucking, nail-biting, tic, masturbation), and excretory problems. The relationships between sleep patterns (bedtime, sleep duration) and the presence of these behaviors were analyzed. Individual / environmental factors that affected problematic behaviors were statistically identified using a tree-form model.

RESULTS

Late bedtime and short sleep duration showed significant adverse effects on children's problematic behaviors - odds ratio (OR): 1.07, 95% confidence interval (CI): 1.03-1.11 and OR: 0.92, 95% CI: 0.87-0.97, respectively. Long television watching time, abnormality at birth, and lack of father's support also showed significant adverse effects on problematic behaviors (OR: 2.34, 95% CI: 1.87-2.94), and significantly affected late bedtime and short sleep duration.

CONCLUSIONS

There were significant associations among sleep patterns, individual / environmental factors, and problematic behaviors in 5-year-old children. Improving children's sleep patterns, reducing the duration of television watching, and improving support from fathers may reduce problematic behaviors.

Factor structure of the Sleep Disturbance Scale for Children (SDSC) in those with Attention Deficit and Hyperactivity Disorder (ADHD)

Objective

Method

Results

Conclusion

•

The original SDSC factor structure could not be replicated in an ADHD sample.

•

The fit of competing factor structures was evaluated.

•

An optimal structure including six-specific and a general factor was identified.

•

The alternative structure reported adequate psychometric properties.

•

The SDSC may be used to yield a total sleep difficulties score in ADHD samples.

Participation of children with disabilities in school: A realist systematic review of psychosocial and environmental factors

Background

In order to make informed decisions about how best to support children and young people with disabilities, effective strategies that facilitate active and meaningful participation in school are required. Clinical factors, diagnosis or impairments somewhat helpful in determining what should be provided in interventions. However, clinical factors alone will not offer a clear view of how to support participation. It is helpful then to look at wider psychosocial and environmental factors. The aim of this review was to synthesise evidence of psychosocial and environmental factors associated with school participation of 4–12 year old children with disabilities to inform the development of participation-fostering interventions.

Methods

A systematic search and synthesis using realist methods was conducted of published research. Papers had to include consideration of psychosocial and/or environment factors for school participation of children with disabilities. The review was completed in accordance with the Realist and Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES) and Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Papers were identified via Boolean search of the electronic databases MEDLINE, CINAHL, PhycINFO and ERIC (January 2006-October 2018). Appraisal focussed on contributions in terms of whether the articles are appropriate for the review (relevance) and research quality (rigour). Data were analyzed using content and thematic analysis methods using a realist framework. A narrative synthesis of results was reported.

Results and implications

We identified 1828 papers in the initial search. Seventy two papers were included in the final synthesis. Synthesis of findings led to three overarching mechanisms representing psychosocial factors for children (1) identity (2) competence and (3) experience of mind and body. Environmental aspects (context) compromised five interrelated areas: (1) structures and organization, (2) peers, (3) adults, (4) space and (5) objects. Our synthesis provides insights on how professionals may organize efforts to improve children’s participation. Consideration of these findings will help to proactively deal with suboptimal participation outcomes. Development of theoretically determined assessments and interventions for management of school participation are now required.

Sleep in youth with autism spectrum disorders: systematic review and meta-analysis of subjective and objective studies

BACKGROUND

Sleep problems are common and impairing in individuals with autism spectrum disorders (ASD). Evidence synthesis including both subjective (ie, measured with questionnaires) and objective (ie, quantified with neurophysiological tools) sleep alterations in youth with ASD is currently lacking.

OBJECTIVE

We conducted a systematic review and meta-analysis of subjective and objective studies sleep studies in youth with ASD.

METHODS

We searched the following electronic databases with no language, date or type of document restriction up to 23 May 2018: PubMed, PsycInfo, Embase+Embase Classic, Ovid Medline and Web of Knowledge. Random-effects models were used. Heterogeneity was assessed with Cochran's Q and I2 statistics. Publication (small studies) bias was assessed with final plots and the Egger's test. Study quality was evaluated with the Newcastle Ottawa Scale. Analyses were conducted using Review Manager and Comprehensive Meta-Analysis. FINDINGS: From a pool of 3359 non-duplicate potentially relevant references, 47 datasets were included in the meta-analyses. Subjective and objective sleep outcome measures were extracted from 37 and 15 studies, respectively. Only five studies were based on comorbidity free, medication-naïve participants. Compared with typically developing controls, youth with ASD significantly differed in 10/14 subjective parameters and in 7/14 objective sleep parameters. The average quality score in the Newcastle-Ottawa Scale was 5.9/9.

DISCUSSION AND CLINICAL IMPLICATIONS

A number of subjective and, to a less extent, objective sleep alterations might characterise youth with ASD, but future studies should assess the impact of pharmacological treatment and psychiatric comorbidities.

Differences in sleep problems between Japanese and Chinese preschoolers: a cross-cultural comparison within the Asian region

STUDY OBJECTIVES

Previous studies have performed cross-cultural comparisons of differences in childhood sleep problems between Asian and Western countries. However, whether such differences can be observed among Asian countries remains unclear. The present study aimed to investigate differences in the pattern of sleep problems between Japanese and Chinese preschoolers.

METHODS

Data were collected from one city in Japan and 10 cities in China. The present study recruited 438 Japanese and 1020 Chinese preschoolers aged four and five years. Sleep problems and patterns were assessed on the basis of parental reports using the Children's Sleep Habits Questionnaire (CSHQ).

RESULTS

Analysis of covariance revealed no significant difference in total CSHQ scores between Japanese and Chinese preschoolers, thus indicating that the total severity of sleep problems did not differ between the groups. Japanese preschoolers exhibited higher scores on the bedtime resistance subscale of the CSHQ than Chinese preschoolers. Conversely, Chinese preschoolers exhibited higher subscale scores for night wakings and sleep-disordered breathing. In addition, Japanese preschoolers exhibited earlier bedtimes and wake times and shorter total sleep times than Chinese preschoolers.

CONCLUSIONS

Our findings indicate that the patterns of sleep problems in preschoolers differ between Japan and China and that such differences may be due to differences in cosleeping practices, bedtime routines, and/or environmental conditions. Thus, investigators studying sleep in preschoolers should consider regional differences in the pattern of sleep problems, even among Asian countries.

Reliability and validity of a brief sleep questionnaire for children in Japan

BACKGROUND

There is a dearth of sleep questionnaires with few items and confirmed reliability and validity that can be used for the early detection of sleep problems in children. The aim of this study was to develop a questionnaire with few items and assess its reliability and validity in both children at high risk of sleep disorders and a community population.

METHODS

Data for analysis were derived from two populations targeted by the Children's Sleep Habits Questionnaire (CSHQ): 178 children attending elementary school and 432 children who visited a pediatric psychiatric hospital (aged 6-12 years). The new questionnaire was constructed as a subset of the CSHQ.

RESULTS

The newly developed short version of the sleep questionnaire for children (19 items) had an acceptable internal consistency (0.65). Using the cutoff value of the CSHQ, the total score of the new questionnaire was confirmed to have discriminant validity (27.2 ± 3.9 vs. 22.0 ± 2.1, p < 0.001) and yielded a sensitivity of 0.83 and specificity of 0.78 by receiver operator characteristic curve analysis. Total score of the new questionnaire was significantly correlated with total score (r = 0.81, p < 0.001) and each subscale score (r = 0.29-0.65, p < 0.001) of the CSHQ.

CONCLUSIONS

The new questionnaire demonstrated an adequate reliability and validity in both high-risk children and a community population, as well as similar screening ability to the CSHQ. It could thus be a convenient instrument to detect sleep problems in children.

Japanese Sleep Questionnaire for Elementary Schoolers (JSQ-ES): validation and population-based score distribution

OBJECTIVE

The Japanese Sleep Questionnaire for Elementary Schoolers (JSQ-ES) was developed to measure the sleep habits and disturbances of Japanese children. The current study aimed to present psychometric properties and describe the score distribution of the JSQ-ES. In addition, it examined correlations between the sleep and daytime behavior of school-aged children.

METHOD

Guardians of 4369 elementary school children and 100 children diagnosed with sleep disorders in two clinics completed the JSQ-ES.

RESULTS

Exploratory factor analysis and confirmatory factor analysis suggested a nine-factor structure. The JSQ-ES internal consistency was 0.876 and 0.907 for the community and clinical groups, respectively. Score distribution differences were observed between the two groups. A cut-off point of 80 was identified for the total JSQ-ES score.

CONCLUSIONS

Exploratory factor analysis and confirmatory factor analysis suggested a nine-factor structure: (1) restless legs syndrome; (2) sleep-disordered breathing; (3) morning symptoms; (4) nighttime awakenings; (5) insomnia; (6) excessive daytime sleepiness; (7) daytime behavior; (8) sleep habits; and (9) irregular/delayed sleep phase. The study verified that the JSQ-ES is a valid and reliable instrument with which to evaluate Japanese sleep habits using a large population-based sample. The JSQ-ES may be useful in both clinical and academic settings.

Prevalence of sleep problems in Japanese preschoolers in a medium-sized city: Community-based survey using the Children's Sleep Habits Questionnaire

Although the mean score of the Children's Sleep Habits Questionnaire (CSHQ) differs between countries, there are no normative data for the CSHQ of Japanese preschoolers based on a community sample. The aims of this study were therefore to present normative data for the CSHQ and determine the prevalence and characteristics of sleep problems in Japanese preschoolers. Parents or the primary caregiver of 482 preschoolers aged 4-5 years completed the CSHQ and the Strength and Difficulties Questionnaire. Approximately 80% of preschoolers scored above the cut-off for sleep disturbance on the CSHQ. In addition, co-sleeping was prevalent in Japanese preschoolers but the habit of co-sleeping contributed little to behavioral and emotional problems. Sleep problems appear to be prevalent in Japanese preschoolers based on the CSHQ, and could be associated with the Japanese sleep habit of co-sleeping.

Preliminary analysis of the concurrent validity of the Spanish translation of the BEARS sleep screening tool for children

WHAT IS KNOWN ON THE SUBJECT?: Paediatric sleep problems are clinical conditions that often coexist with other mental health problems and meet criteria that warrant the implementation of screening procedures, including high prevalence, and significant clinical impact. Researchers have designed the BEARS, a user-friendly paediatric sleep screening tool that seems to increase the amount of sleep information recorded, as well as the likelihood of identifying sleep problems during routine health encounters. Nonetheless, there are no studies using the BEARS in Spanish-speaking samples. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: Using a sample of children with mental health problems, this study provides support for the use of the Spanish version of the BEARS to identify the most common sleep problems seen in paediatric populations. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Considering how frequent sleep problems are, it is especially important for health professionals working with children in general, and with children with mental health problems in particular, to be aware of and be encouraged to use simple brief screening tools for paediatric sleep problems.

ABSTRACT

Objective Research studies describe a high prevalence of sleep problems in children with mental health problems, up to 50%, and its role as a risk factor in the development of psychopathology. These often go unnoticed and are not evaluated in the clinical field. Our objective was to assess the concurrent validity of the BEARS, a brief paediatric sleep screening instrument, using the Children Sleep Habits Questionnaire (CSHQ) as the comparison instrument. Methods In this cross-sectional descriptive study, the BEARS was applied by a registered nurse to a sample of parents of children aged 2-16 years (n = 60, 71.7% male) who attended a mental healthcare facility (located in Murcia, Spain) for the first time to receive a group psychoeducational intervention. The association between the information collected with the BEARS and scores on the related subscales of the CSHQ was assessed by Mann-Whitney U tests. Results Children who, according to the BEARS, had a sleep problem obtained scores on the CSHQ-related subscales significantly higher than children who did not have a sleep problem (all P_s  < 0.05). Conclusion Our results support the concurrent validity of the Spanish translation of the BEARS to detect sleep problems in paediatric nursing assessments. Further studies, with bigger and more heterogeneous samples, are warranted.

Influence of sleep-onset time on the development of 18-month-old infants: Japan Children's cohort study

OBJECTIVE

We report here the influence of sleep patterns on the development of infants in Japan. A total of 479 infants were registered in two different Japanese cities. Direct neurological observations were performed by licensed pediatric neurologists.

METHOD

We designed a prospective cohort study and identified the sleep factors of children showing atypical development. The Kinder Infant Developmental Scale (KIDS) was used to evaluate the infant developmental quotient (DQ); we also applied a neurobehavioral screening battery. Neurobehavioral observations in 18-month-old infants were designed to check all developmental categories within the three areas of motor function, language, and social function. Based on the observations, each infant was classified as having "atypical development" or "typical development".

RESULT

We found that later sleep onset time (>22:00 h), and longer naps during the day each had significant positive correlations with atypical development patterns in 18-month-old infants. For each hour the infant sleep-onset time extended past 22:00 h, the infants showed worse neurodevelopmental outcomes, at an odds ratio increase of 2.944.

CONCLUSION

Although our results may be confounded by sleep problems resulting from pre-existing developmental disabilities, we can safely conclude that appropriate sleeping habits are important for healthy development in 18-month-old infants.