Sleep in children with neurodevelopmental difficulties

Modification of a parent-report sleep scale for individuals with CDKL5 deficiency disorder: a psychometric study

STUDY OBJECTIVES

Sleep difficulties are common in CDKL5 deficiency disorder, a developmental and epileptic encephalopathy. This study evaluated the factor structure of the Disorders of Initiating and Maintaining Sleep (DIMS), Disorders of Excessive Somnolence (DOES), and Sleep Breathing Disorders domains of the Sleep Disturbance Scale for Children for CDKL5 deficiency disorder.

METHODS

A cross-sectional psychometric study design was used. Data were collected for 125 individuals aged 3 years or older who attended a United States Centers of Excellence clinic or registered with the International CDKL5 Disorder Database.

RESULTS

The median age was 10.3 years (range 3.2-40.7 years) and 105 (84%) were female. Two of the 3 Sleep Breathing Disorders items were not observed by most respondents and analysis was restricted to the DIMS and DOES domains. Using all items in the initial confirmatory factor analysis, 2 items in the DIMS domain and 1 item in the DOES domain loaded poorly. After deleting these items and repeating the analysis, item loading (.524-.814) and internal consistency (DIMS: .78, DOES: .76) statistics were good. The square of the interdomain correlation coefficient was .17, less than average variance extracted values for both domains and indicating good discriminant validity. The Tucker-Lewis and Comparative Fit indices were slightly lower than the threshold of > .9 for establishing goodness of fit.

CONCLUSIONS

The modified DIMS and DOES domains from the Sleep Disturbance Scale for Children could be suitable clinical outcome assessments of insomnia and related impairments in CDKL5 deficiency disorder and potentially other developmental and epileptic encephalopathy conditions.

CITATION

Saldaris JM, Demarest S, Jacoby P, et al. Modification of a parent-report sleep scale for individuals with CDKL5 deficiency disorder: a psychometric study. J Clin Sleep Med. 2024;20 (12):1887-1893.

Sleep problems of children with Down syndrome in northern China

BACKGROUND

Limited research has looked at the present-day sleep problems among Chinese children with Down syndrome (DS). This study aimed to investigate the situation of the sleep problems of school-aged children with DS in northern China.

METHODS

Parents of children with DS were a convenience sample recruited through the special education schools of Shandong Province in China. The Chinese version of the Children's Sleep Habits Questionnaire was applied to assess the sleep problems of children with DS.

RESULTS

Parents of 334 children with DS reported the average sleep duration was 9.7 (9.3-10.2) hours per night, and 62.0% of children with DS were reported sleeping less than 10 h per night. Additionally, the total prevalence rate of sleep problems among children with DS was 69.8%. Sleep-disordered breathing (59.2%), sleep duration (33.8%) and bedtime resistance (32.0%) were the three most commonly reported sleeping problems. Younger children with DS (age 6-8 years) had severe problems with bedtime resistance, sleep anxiety and parasomnias than older children with DS (age 9-12 years) (all P < 0.05).

CONCLUSION

Sleep problems are prominent among children with DS in northern China and are worthy of attention. Caregivers and health professionals should raise awareness of sleep problems in this group of children and implement targeted interventions to improve their sleep quality as early as possible.

Tolerance of polysomnography in children with neurodevelopmental disorders compared to neurotypical peers

STUDY OBJECTIVES

Diagnostic polysomnography (PSG) is the gold standard test to evaluate sleep-disordered breathing in children. Little is known about how children with neurodevelopmental disorders (NDD) tolerate electrodes and sensors in PSG compared to neurotypical children.

METHODS

In this retrospective cohort study of children > 12 months of age who underwent diagnostic PSG at our center from 01/01/2021-30/06/2021, we used sleep technician and physician reports to determine how PSG was tolerated in children with NDD compared to neurotypical children. Subanalyses included tolerance of individual electrodes and sensors and subgroups of NDD (eg, Trisomy 21).

RESULTS

A total of 132 children with a NDD and 139 neurotypical children underwent diagnostic PSG. The median age of all children was 8 years, 39% were female, and 50% had a sleep disorder identified on PSG, with no significant differences between NDD and neurotypical groups. The most poorly tolerated sensors for all children were the nasal prongs (poorly tolerated in 30% of all children), followed by thermistor (14%) and electroencephalography electrodes (6%). Children with NDD were > 3 times more likely (odds ratio 3.1, 95% confidence interval 1.8-5.3) to experience problems tolerating any study leads than neurotypical children. Subgroup analysis revealed children with Trisomy 21 had the greatest difficulty tolerating PSG set-up and leads.

CONCLUSIONS

This retrospective study demonstrates that children with neurodevelopmental disorders are less likely to tolerate PSG monitoring than neurotypical children and highlights the need to develop alternative measures for evaluation of sleep disorders in this population.

CITATION

Lanzlinger D, Kevat A, Collaro A, Poh SH, Pérez WP, Chawla J. Tolerance of polysomnography in children with neurodevelopmental disorders compared to neurotypical peers. J Clin Sleep Med. 2023;19(9):1625-1631.

Sleep Disorders in Low-Risk Preterm Infants and Toddlers

Sleep disorders are particularly important in the development of children, affecting the emotional, behavioural, and cognitive spheres. The incidence of these disorders has been assessed in different types of populations, including patients with a history of premature birth, who, from the literature data, would seem to have an increased incidence of sleep disorders at school age. The aims of the present study are: (i.) to assess the presence of sleep disorders in a population of very preterm infants at 6-36 months who are at low risk of neurological impairments using the Italian version of the Sleep Disturbance Scale for Children (SDSC) adapted for this age group, and (ii.) to identify possible differences from a control group of term-born infants. A total of 217 low-risk preterm and 129 typically developing infants and toddlers were included in the study. We found no differences in the SDSC total and the factor scores between these two populations of infants. Low-risk preterm infants and toddlers showed similar incidences of sleep disorders to their term-born peers. Further clinical assessments will be needed to confirm these data at school age.

The effect of intensive rehabilitation treatment on sleep disorder in children with motor delays

BACKGROUND

Although the importance of sleep problems has been increasingly emphasized due to the effects on children's development and children's and families' daytime behaviors, physical health, and quality of life, they have been overlooked in clinical practice. However, there have been few studies on the effects of rehabilitation on sleep problems. Therefore, in this study, we investigated the effects of an intensive rehabilitation program on sleep problems in children with developmental delays (DD).

METHODS

We included 36 children with DD (30 outpatients, 6 inpatients) and their caregivers who completed all items on the Sleep Disturbance Scale for Children. Of the children with DD, 19 (59.3%) had cerebral palsy (CP) and 13 (40.7%) had DD of non-CP origins, of which 6 (18.8%) had prematurity, 4 (12.5%) had genetic causes, and 3 (9.4%) had an unknown origin. Changes in sleep problems after the intensive rehabilitation program were evaluated using a paired or unpaired t-test, depending on the distribution of the continuous variables.

RESULTS

After the intensive rehabilitation program, in 36 children with DD, there was a significant improvement in the difficulty in initiating and maintaining sleep (DIMS) sub-score (p < 0.05). However, there was no significant improvement in the total score or other sub-scores, such as those for sleep breathing disorders (SBD), disorders of arousal (DA), sleep-wake transition disorders (SWTD), disorders of excessive somnolence (DOES), and sleep hyperhidrosis (SH). In the subgroup analysis according to the cause of DD, children with CP had a significant improvement in DIMS and DOES sub-scores (p < 0.05).

CONCLUSION

The intensive rehabilitation program, consisting of more than two sessions per day, effectively alleviated sleep problems in children with DD, especially in those with CP. Among the sleep problems, the intensive rehabilitative program was most effective at improving the DIMS. However, further prospective studies with a larger number of patients with DD and a more standardized protocol are necessary to generalize this effect.

Sleep and behavioral problems in Down syndrome: differences between school age and adolescence

Background

Individuals with Down syndrome (DS) are at risk of developing sleep problems. In spite of the well-established knowledge on the presence of sleep difficulties in DS individuals and the associated emotional and behavioral problems, less is known about the possible differences in the kind of associations between sleep and emotional/behavioral problems across different age ranges.

Methods

In this retrospective study, we included 289 participants with DS aged 6-18 years with the aims to explore differences in the distribution of sleep problems between specific age groups (school age vs. adolescence) and to identify specific age-based associations between sleep problems and emotional/behavioral problems.

Results

Some differences in the distribution of sleep problems have emerged between age groups. Moreover, differences in the patterns of association between emotional/behavioral difficulties and sleep problems-in particular, sleep-related breathing difficulties and parasomnias-have been observed. However, sleep-wake transition disorders and excessive daily somnolence appear to be related to emotional and behavioral problems (both internalizing and externalizing), in general, across school age and adolescence.

Discussion

These results remark the importance of appropriate neuropsychiatric and psychological evaluation taking into account the age-specific needs and features of individuals with DS.

Research progress on the pathogenesis of CDKL5 pathogenic variants and related encephalopathy

Cyclin-dependent kinase-like 5 (CDKL5) is a gene encoding a serine/threonine kinase that possesses an N-terminal catalytic domain and a large C-terminal domain and is located on the short arm of the X-chromosome at position 22 (Xp22). CDKL5 regulates neuronal migration, axonal growth, dendritic morphogenesis, and synaptic development and affects synaptic function. Pathogenic variants include deletions, truncations, splice variants, and missense variants. The specificity of CDKL5 is mainly determined by the shared sequence of amino acid residues, which is the phosphorylation site of the target protein with the motif Arg-Pro-X-Ser/Thr-Ala/Pro/Gly/Ser (R-P-X-[S/T]-[A/G/P/S]). Developmental encephalopathy caused by pathogenic variants of CDKL5 has a variety of nervous system symptoms, such as epilepsy, hypotonia, growth retardation, dyskinesia, cortical visual impairment, sleep disorders, and other clinical symptoms. This review summarizes the mechanism of CDKL5-induced allogeneic lesions in the nervous system and the clinical manifestations of related encephalopathy.   Conclusion: This review clarifies CDKL5's participation in neurodevelopmental diseases as well as its crucial function in dividing cells, cultured neurons, knockout mice, and human iPSC-derived neurons. CDKL5 variants help identify clinical diagnostic biomarkers. Although a few direct substrates of CDKL5 have been identified, more must be found in order to fully comprehend the signaling pathways connected to CDKL5 in the brain and the mechanisms that underlie its activities.

Negative impact of insomnia and daytime sleepiness on quality of life in individuals with the cyclin-dependent kinase-like 5 deficiency disorder

Cyclin-dependent kinase-like 5 (CDKL5) gene pathogenic variants result in CDKL5 deficiency disorder (CDD). Early onset intractable epilepsy and severe developmental delays are prominent symptoms of CDD. Comorbid sleep disturbances are a major concerning symptom for families. We aimed to explore the relationship between insomnia, daytime sleepiness, sleep medications and quality of life in children with CDD. Caregivers of 129 children with CDD in the International CDKL5 Disorder Database completed the Quality-of-Life Inventory-Disability (QI-Disability) questionnaire and "Disorders of Maintaining Sleep" (DIMS) and the "Disorders of Excessive Somnolence" (DOES) items of the Sleep Disturbance Scale for Children. Adjusting for covariates, a unit increase in DOES score was associated with reduced quality of life total (coefficient -3.06, 95% confidence interval [CI] 1.35-7.80), physical health (coefficient -7.20, 95% CI -10.64, -3.76) and negative emotions (coefficient -3.90, 95% CI -7.38, -0.42) scores. Adjusting for covariates, a unit increase in DIMS score was associated with reduced negative emotions (coefficient -6.02, 95% CI -10.18, -2.86). Use of sleep medications had small influences on the effect sizes. This study highlights the importance of sleep problems as a determinant of quality of life in children with CDD, consistent with effects observed for other groups of children with intellectual disability. Excessive daytime sleepiness was particularly associated with detrimental effects on quality of life. Further research in optimal behavioural and pharmaceutical management of sleep problems for this population is required.

Modelling quality of life in children with intellectual disability using regression trees

AIM

To identify factors associated with quality of life (QoL) in children with intellectual disability. We aimed to identify patterns of association not observable in previous hypothesis-driven regression modelling using the same data set from a cross-sectional observational study.

METHOD

A questionnaire was completed by 442 caregivers of children with confirmed intellectual disability and a diagnosis of autism spectrum disorder, cerebral palsy, Down syndrome, or Rett syndrome. The Quality of Life Inventory-Disability (QI-Disability) questionnaire was used to assess child QoL. Independent variables described the child's health, functional abilities, community participation, and sociodemographics. The R package rpart was used to build the regression trees.

RESULTS

The mean total QI-Disability score was 69.2 out of a maximum 100. The subgroup with the lowest QoL scores comprised children with a high degree of daytime sleepiness (n=74, mean 57.5) while the subgroup with the highest QoL scores (n=91, mean 80.3) comprised children with little daytime sleepiness who participated more frequently in community activities and displayed good eye contact while listening.

INTERPRETATION

Regression tree analysis provides insights into the relative importance of associated factors. Sleep problems and community participation were more important than functional abilities in accounting for differences in QoL.

WHAT THIS PAPER ADDS

A hypothesis-free regression tree analysis enables examination of multiple factors potentially influencing quality of life (QoL) in children with intellectual disability. Functional abilities were less strongly associated with QoL than sleep problems and community participation.

Sleep and behavioral problems in preschool-age children with Down syndrome

Sleep is a major concern, especially in people with Down Syndrome (DS). Beyond Obstructive Sleep Apnea, a number of other sleep difficulties have been reported in children with DS, such as delayed sleep onset, night-time awakenings, and early morning awakenings. The detrimental effect of sleep difficulties seems to contribute to and exacerbate the cognitive and behavioral outcomes of DS. Although the screening for sleep disorders is recommended early in age in DS, only a few studies have evaluated the sleep profile in preschool-age children with DS. The aim of the current study was to assess the association between sleep disturbances and behavioral problems in a group of preschool-age children with DS, by means of a feasible and easy-to-administer parent-report questionnaires. Seventy-one preschool-age children with DS, ranging in age from 3 to 5.11 years, were included in this retrospective study. Sleep disturbances were evaluated by means of the Sleep Disturbance Scale for Children, while emotional and behavioral problems by means of the Child Behavior Checklist. Sleep breathing disorders were the most frequent sleep difficulties reported by parents. Moreover, children with clinical scores in total sleep problems exhibited elevation of psychopathological symptoms, namely Total problems, Affective problems, Anxiety problems, Pervasive Developmental Problems, and Attention Deficit/Hyperactivity Problems. The identification of the broader connection between sleep difficulties and emotional and behavioral problems in preschool-age children with DS leads to important considerations for intervention.

CDKL5 deficiency disorder: clinical features, diagnosis, and management

CDKL5 deficiency disorder (CDD) was first identified as a cause of human disease in 2004. Although initially considered a variant of Rett syndrome, CDD is now recognised as an independent disorder and classified as a developmental epileptic encephalopathy. It is characterised by early-onset (generally within the first 2 months of life) seizures that are usually refractory to polypharmacy. Development is severely impaired in patients with CDD, with only a quarter of girls and a smaller proportion of boys achieving independent walking; however, there is clinical variability, which is probably genetically determined. Gastrointestinal, sleep, and musculoskeletal problems are common in CDD, as in other developmental epileptic encephalopathies, but the prevalence of cerebral visual impairment appears higher in CDD. Clinicians diagnosing infants with CDD need to be familiar with the complexities of this disorder to provide appropriate counselling to the patients' families. Despite some benefit from ketogenic diets and vagal nerve stimulation, there has been little evidence that conventional antiseizure medications or their combinations are helpful in CDD, but further treatment trials are finally underway.

Functional links between thermoregulation and sleep in children with neurodevelopmental and chronic health conditions

The bi-directional relationship between sleep and wake is recognized as important for all children. It is particularly consequential for children who have neurodevelopmental disorders (NDDs) or health conditions which challenge their sleep and biological rhythms, and their ability to maintain rhythms of participation in everyday activities. There are many studies which report the diverse reasons for disruption to sleep in these populations. Predominantly, there is focus on respiratory, pharmaceutical, and behavioral approaches to management. There is, however, little exploration and explanation of the important effects of body thermoregulation on children's sleep-wake patterns, and associated behaviors. Circadian patterns of sleep-wake are dependent on patterns of body temperature change, large enough to induce sleep preparedness but remaining within a range to avoid sleep disturbances when active thermoregulatory responses against heat or cold are elicited (to maintain thermoneutrality). Additionally, the subjective notion of thermal comfort (which coincides with the objective concept of thermoneutrality) is of interest as part of general comfort and associated behavioral responses for sleep onset and maintenance. Children's thermoregulation and thermal comfort are affected by diverse biological functions, as well as their participation in everyday activities, within their everyday environments. Hence, the aforementioned populations are additionally vulnerable to disruption of their thermoregulatory system and their capacity for balance of sleep and wakefulness. The purpose of this paper is to present hitherto overlooked information, for consideration by researchers and clinicians toward determining assessment and intervention approaches to support children's thermoregulation functions and promote their subjective thermal comfort, for improved regulation of their sleep and wake functions.

Sleep problems in preschool children at the child development center with different developmental status: A questionnaire survey

OBJECTIVE

To investigate the relationship between sleep problems and development in preschool children with suspected developmental delay.

METHODS

A total of 192 preschool children (mean age 4 years; 131 males, 61 females) were recruited from the Child Development Clinic, including 98 preterm children and 94 age- and sex-matched full-term children. All participants underwent evaluation of gross motor, fine motor and speech performance. All parents of all participants completed the Children's Sleep Habits Questionnaire (CSHQ). Some of the participants also underwent psychological evaluation. Correlation analysis and community network analysis were used to investigate the interactions.

RESULTS

The developmental status was: 75.5% developmental delay, 19.3% borderline development, and 5.2% normal development. Eighty-nine percent of the subjects had abnormal CSHQ scores. Age, gestational age, speech development, cognitive development, and socio-emotional development were significantly correlated with the CSHQ. Significant interactions between sleep problems and development were noted mostly in the preterm group.

CONCLUSION

High prevalence of sleep disturbances in children at the Child Development Center was noted and associated with multiple factors. Therefore, during the multidisciplinary evaluation of children with possible developmental delay, inquiring about their sleep quality and habits is strongly recommended. Mitigating sleep problems enhances the efficacy of early intervention programs.

Determinants of sleep problems in children with intellectual disability

Children with intellectual disabilities are more likely to experience sleep disorders of insomnia, excessive daytime sleepiness and sleep breathing disorders than typically developing children. The present study examined risk factors for these sleep disorders in 447 children (aged 5-18 years), diagnosed with an intellectual disability and comorbid autism spectrum disorder, cerebral palsy, Down syndrome or Rett syndrome. Primary caregivers reported on their child's sleep using the Sleep Disturbance Scale for Children (SDSC), as well as medical comorbidities and functional abilities. Multivariate linear and logistic regressions were used to examine the effects of these factors on SDSC t scores and a binary indicator, respectively for the relevant subscales. Receiving operating characteristic curves were generated for each logistic regression model to determine their ability to discriminate between poor and good sleep. Comorbidities rather than functional abilities were associated with poorer sleep. In particular, recurrent pain, frequent seizures, frequent coughing, constipation and prescription of sleep medications were associated with abnormal sleep across the entire sample, but predictors differed between diagnostic groups. The present study suggests that comorbidities are more strongly associated with quality of sleep than functional impairments. The present study provides new information on potential associations between frequent coughing, prescription sleep medications and sleep quality that should be further investigated.

Sleep-related learning in Williams Syndrome and Down's Syndrome

This chapter addresses sleep research challenges for the study of neurodevelopmental disorders drawing upon two disorders such as Down Syndrome and Williams syndrome. General sleep problems are outlined here, however particular consideration is given to the syndrome-specific issues or challenges that may be crucial to advancing our understanding of sleep-related cognitive and behavioral issues.