Children's sleep and daytime functioning: Increasing heritability and environmental associations with sibling conflict

The Effect of Mother's Mediation on Sibling Conflict Among Chinese Children

Thirty-four Chinese families (each consisting of a mother and two children) were recruited to participate in this study. The firstborn children had an average age of 12.00 ± 2.07 years, while the second-born children averaged 7.57 ± 2.51 years old. The families were randomly divided into mediation and control groups. The mothers in the mediation group underwent mediation training, whereas those in the control group received no treatment. Analysis of variance (ANOVA) and Chi-square tests were utilized to analyze data on sibling conflict. Results indicated that the mothers in the mediation group reported significantly less negative behavior in helping their children resolve sibling disputes compared to those in the control group. Mediation group mothers reported significantly fewer sibling conflicts compared to control group mothers. No significant differences were observed between children in the mediation group and the control group regarding positive and negative behaviors recorded by mothers. These results indicate that mediation training may better equip Chinese mothers with the ability to resolve sibling conflicts in their families.

Parental non-involvement strategy for handling sibling conflict on social avoidance in migrant children: Chain mediation of sibling conflict and parent-child conflict

In the process of urbanization, the social adaptation of migrant children has become an important issue in their development. This study adopts family systems theory and ecological systems theory to examine the effects of parental non-involvement strategies in handling sibling conflict on migrant children's social avoidance. It also investigates the mediating role of sibling conflict and parent-child conflict. The results of the study, reported by parents of 253 mobile children with siblings, suggest that parental strategies of not intervening in sibling conflict are an important factor influencing the development of social avoidance in mobile children. The Parental strategy of not intervening in sibling conflict had an effect on migrant children's social avoidance through the separate mediating effect of parent-child conflict, and also through the chained mediating effect of sibling conflict and parent-child conflict. The study also found that the separate mediating effect of sibling conflict was not significant. This study contributes to the research on the relationship between parental non-intervention in sibling conflict and migrant children's social avoidance. It also highlights the impact of sibling conflict and parent-child conflict on migrant children's social avoidance by establishing and validating a comprehensive research model. The results of the study can help parents establish close parent-child relationships for migrant children and provide scientific guidance for children to develop positive sibling relationships. This, in turn, can assist migrant children in better adapting to a new social environment.

An investigation of computer-game addiction, physical activity level, quality of life and sleep of children with a sibling with a chronic condition

BACKGROUND

It is known that chronic condition also affects siblings without chronic illness. Healthy siblings of children with a chronic condition and aged 9-14 years and healthy children with a sibling without chronic illness and their parents were included in the study.

AIM

The aim of our study was to examine the internet-game addiction, physical activity, quality of life and sleep in children with a sibling with chronic condition and compare them with their peers with a healthy sibling.

METHODS

Computer game addiction, physical activity, sleep quality and quality of life were evaluated respectively by Computer Game Addiction Scale for Children, Child Physical Activity Questionnaire, Children's Sleep Disorder Scale and Children's Quality of Life Scale.

RESULTS

While the mean age of 75 children with chronically ill siblings was 10.65 ± 1.59 years, the mean age of 75 healthy children with healthy siblings was 10.46 ± 2.09 years. It was observed that children with a sibling with a chronic condition were more tend to computer-game addiction, had lower sleep quality, lower quality of life in terms of school functionality and psychosocial health compared to children with a healthy sibling (p < 0.05).

CONCLUSIONS

It was revealed that in families with children with a chronic condition, siblings with no health problems should also be evaluated in psychosocial terms and supported by appropriate approaches, such as to increase the level of physical activity.

Concordance in parent-child and sibling actigraphy-measured sleep: Evidence among early adolescent twins and primary caregivers

STUDY OBJECTIVES

Growing evidence suggests concordance between parent and youth sleep. However, no known study has simultaneously examined concordance among siblings' sleep patterns. This study investigated daily and average concordance in (1) parent-youth and (2) sibling actigraphy-measured sleep, as well as the degree to which sibling concordance varied by sleeping arrangements.

METHODS

516 twin siblings (Mage = 10.74, 51% female; 30% monozygotic (MZ) twin pairs, 37% same-sex dizygotic pairs (DZ-ss), 33% opposite-sex DZ pairs (DZ-os)) and their primary caregivers (Mage = 40.59, 95% female) wore wrist-based accelerometers for 7 consecutive nights to measure sleep duration, efficiency, midpoint time, and latency. Primary caregivers also reported on demographics, youth pubertal status, and room-sharing. Two-level multilevel models were estimated to examine daily and average concordance in parent-youth and sibling sleep.

RESULTS

Daily concordance was observed between parent and youth sleep duration and midpoint; average concordance was found for sleep duration, midpoint, and latency. Within sibling dyads, daily and average concordance was evident across all sleep parameters (duration, efficiency, midpoint, latency), with generally stronger concordance patterns for MZ than DZ twin pairs, and for twins who shared a room with their co-twin.

CONCLUSIONS

This is the first known study to document concordance among parent-youth and siblings' actigraphy-measured sleep within the same study (i.e., triad). Our findings can help inform the development of family-level interventions targeting daily and overall sleep hygiene.

Direct and Indirect Paths between Parental Marital Conflict and Children's Sibling Conflict in Chinese Families

Links between parental marital conflict and children's sibling conflict have been well examined; however, the underlying mechanism of this link needs to be further studied. This study investigated the mediating role of parental intervention styles (i.e. child-centered strategies, control strategies, and nonintervention strategies) and children's control behavior toward their sibling between parental marital conflict and children's sibling conflict. We recruited 689 Chinese children (53.7% girls) aged 8-13 years to participate in the study. Results indicated that parental marital conflict, control strategies, nonintervention strategies, and children's control behavior toward sibling were positively associated with sibling conflict among children. Child-centered strategies were negatively correlated with children's sibling conflict. Furthermore, control and nonintervention strategies of parents and control behavior of children toward sibling simultaneously partially mediated between parental marital and child-sibling conflict. The mediating role of child-centered strategies was not significant. These findings suggest that parental strategies of control and nonintervention and children's control behavior toward their sibling may increase the risk of sibling conflict among children after repeated exposure to parental marital conflict. In contrast, child-centered strategies may be a protective factor for children regarding sibling conflict. Current findings confirm the combined effects of parent and child behavior on child-sibling conflict. They also help parents deal with sibling conflict among their children and promote more positive relationships among siblings.

Relationships between parenting style and sibling conflicts: A meta-analysis

Previous studies have shown that sibling conflicts are detrimental to physical and psychological development, as well as long-term human development. Although many studies have discovered relations between parenting style and sibling conflicts, these findings were contentious and did not provide a universal solution. Therefore, the meta-analysis was used as the method to determine the nature and magnitude of the relationships. There were a total of 14,356 participants in the 16 included studies, from which 55 effect sizes were extracted. According to the overall meta-analysis results, authoritative parenting (r = -0.201) did have the potential to reduce sibling conflicts. Neglectful (r = 0.389), inconsistent (r = 0.364), indulgent (r = 0.293), and authoritarian (r = 0.235) parenting styles were related to sibling conflicts in a positive way. Moreover, the study investigated the effectiveness of several moderator variables, such as children's gender, age, region, outcome measure, and publication year. The research indicates that authoritative parenting is a protective factor of sibling conflicts. Moderator analyses found that gender, age, region, outcome measure, and publication year played moderating roles in the relationships. Finally, research limitations in the current study and expectations for future research, as well as theoretical contributions and implications for parenting practice, were presented.

Systematic review registration

[https://inplasy.com/inplasy-2022-8-0020/], identifier [INPLASY202280020].

Effect of the INSIGHT Firstborn Parenting Intervention on Secondborn Sleep

BACKGROUND AND OBJECTIVES

The Intervention Nurses Start Infants Growing on Healthy Trajectories (INSIGHT) responsive parenting (RP) intervention for first-time mothers improved firstborn infant sleep compared with controls. The goals of this analysis were to test intervention spillover effects on secondborn siblings and examine birth order differences in infant sleep.

METHODS

Secondborns (n = 117) of INSIGHT mothers were enrolled in an observational cohort, SIBSIGHT. The Brief Infant Sleep Questionnaire was collected at 3, 16, and 52 weeks. Generalized linear mixed models assessed differences among secondborns by firstborn randomization, as well as birth order differences at 16 and 52 weeks.

RESULTS

The RP group secondborns slept 42 minutes longer at night (95% confidence interval [95% CI]: 19-64) and 53 minutes longer total (95% CI: 17-90) than control secondborns. RP secondborns were more likely to self-soothe to sleep (odds ratio [OR] = 2.0, 95% CI: 1.1-3.7) and less likely to be fed back to sleep after waking (OR = 0.5, 95% CI: 0.3-0.9) than secondborns of control mothers. RP secondborns were more likely to have a bedtime ≤8 pm at 3 (OR = 2.9, 95% CI: 1.1-7.7) and 16 weeks (OR = 4.7, 95% CI: 2.0-11.0). Few differences in sleep parenting practices were observed when comparing siblings within families. Secondborns slept 37 minutes longer than firstborns at 16 weeks (CI: 7-67, P = .03).

CONCLUSIONS

The INSIGHT RP intervention for first-time mothers had a spillover effect to secondborns, positively impacting sleep duration and behaviors. Intervening with first-time mothers benefits both firstborns and subsequent children.

Sleep disturbances in ADHD: investigating the contribution of polygenic liability for ADHD and sleep-related phenotypes

Sleep disturbances are common in attention deficit hyperactivity disorder (ADHD) and associated with poor outcomes. We tested whether, in children with ADHD, (1) polygenic liability for sleep phenotypes is over- or under-transmitted from parents, (2) this liability is linked to comorbid sleep disturbances, and (3) ADHD genetic risk is associated with comorbid sleep disturbances. We derived polygenic scores (PGS) for insomnia, chronotype, sleep duration, and ADHD, in 758 children (5-18 years old) diagnosed with ADHD and their parents. We conducted polygenic transmission disequilibrium tests for each sleep PGS in complete parent-offspring ADHD trios (N = 328) and an independent replication sample of ADHD trios (N = 844). Next, we tested whether insomnia, sleep duration, and ADHD PGS were associated with co-occurring sleep phenotypes (hypersomnia, insomnia, restless sleep, poor sleep quality, and nightmares) in children with ADHD. Children's insomnia and chronotype PGS did not differ from mid-parent average PGS but long sleep duration PGS were significantly over-transmitted to children with ADHD. This was supported by a combined analysis using the replication sample. Insomnia, sleep duration, and ADHD PGS were not associated with comorbid sleep disturbances. There is weak evidence that children with ADHD over-inherit polygenic liability for longer sleep duration and do not differentially inherit polygenic liability for insomnia or chronotype. There was insufficient evidence that childhood sleep disturbances were driven by polygenic liability for ADHD or sleep traits, suggesting that sleep disturbances in ADHD may be aetiologically different to general population sleep phenotypes and do not index greater ADHD genetic risk burden.

Heritability of Sleep and Its Disorders in Childhood and Adolescence

PURPOSE OF REVIEW

This review summarizes recent literature on the heritability of sleep and sleep disorders in childhood and adolescence. We also identify gaps in the literature and priorities for future research.

RECENT FINDINGS

Findings indicate that age, measurement method, reporter, and timing of sleep measurements can influence heritability estimates. Recent genome-wide association studies (GWAS) have identified differences in the heritability of sleep problems when ancestral differences are considered, but sample sizes are small compared to adult GWAS. Most studies focus on sleep variables in the full range rather than on disorder. Studies using objective measures of sleep typically comprised small samples.

SUMMARY

Current evidence demonstrates a wide range of heritability estimates across sleep phenotypes in childhood and adolescence, but research in larger samples, particularly using objective sleep measures and GWAS, is needed. Further understanding of environmental mechanisms and the interaction between genes and environment is key for future research.

Actigraphic sleep and cortisol in middle childhood: A multivariate behavioral genetics model

To date, behavioral genetic studies investigated either sleep or cortisol levels in middle childhood, but not both simultaneously. Therefore, a pertinent question is the degree to which genetic factors and environmental factor contribute to the correlation between sleep and cortisol levels. To address this question, we employed the classical twin design. We measured sleep in 6-9-year-old twins (N = 436 twin pairs, “Together Unique” study) over four consecutive nights using actigraphy, and we measured morning cortisol on two consecutive days. Sleep duration, sleep efficiency, and wake episodes were used as indicators of sleep. Morning cortisol level was used as cortisol indicator. A structural equation model was fitted to estimate the contribution of additive genetic effects (A), shared (common) environmental effects, (C) and unique environmental effects (E) to phenotypic variances and covariances. Age, cohort, and sex were included as covariates. The heritability of sleep duration, sleep efficiency, and wake episodes were 52%, 45%, and 55%, respectively. Common environmental factors played no significant role. High genetic correlations between sleep duration and sleep efficiency and high genetic correlations between sleep efficiency and wake episodes were found. Shared environmental (29%) and unique environmental factors (53%) explained the variance in morning cortisol levels. Because the sleep and cortisol measures were found to be uncorrelated, we did not consider genetic and environmental contributions to the association between the sleep and cortisol measures. Our findings indicate that sleep duration, sleep efficiency, and wake episodes in children are mostly impacted by genetic factors and by unique environmental factors (including measurement error).

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Sleep duration, efficiency and wake episodes are moderately heritable.

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A high genetic correlation underlies sleep duration and sleep efficiency.

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A high genetic correlation underlies sleep efficiency and wake episodes.

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Cortisol and sleep were not (genetically) correlated.

Correlates of Sleep Duration in Early Childhood: A Systematic Review

OBJECTIVE

This systematic review aimed to summarize correlates of sleep duration in children under 5 years of age.

METHODS

Six electronic databases (PubMed, PsycINFO, MEDLINE, CINAHL, SPORTDiscus, and Scopus) were searched from inception to May 2019. Observational studies and intervention studies reporting cross-sectional results from baseline data were considered. Data were extracted using a predesigned form and potential correlates were categorized following a sociological framework.

RESULTS

One-hundred and sixteen studies, representing 329,166 children, met the inclusion criteria, with a high risk of bias in 62 included studies. A total of 83 correlates of sleep duration were identified. Among the associations studied four or more times, correlates of nap duration were child's age and nighttime sleep onset/bedtime; correlates of nighttime sleep duration were household income, parent marital status, parental adiposity level, nighttime sleep duration at younger age, nighttime sleep onset/bedtime, nighttime sleep wakeup time, and frequency of current bedtime routine; correlate of total sleep duration was screen time.

CONCLUSIONS

Young children from low-income households, single families, or having overweight parents may be at risk for short sleep duration. Promoting healthy sleep duration from an early age appears essential. Effective practices may include encouraging an earlier bedtime, limiting screen time, and establishing a regular bedtime routine. The absence of consistent evidence in the psychological, cognitive, and emotional domain as well as the physical environmental domain warrants further research.

Children's objective sleep assessed with wrist-based accelerometers: strong heritability of objective quantity and quality unique from parent-reported sleep

Children's poor sleep is a risk factor for lower cognitive functioning and internalizing and externalizing problems. It is unclear whether genetic and environmental influences vary based on sleep assessment and no studies to date have examined genetic and environmental contributions to links between multiple objective and subjective sleep indicators. Further, nearly all heritability studies rely on subjective parent- or self-report measures of sleep duration and problems. Given these gaps in the literature, we (1) modeled genetic and environmental influences on multiple objective and subjective sleep indicators and (2) estimated genetic and environmental covariances between objective and subjective sleep indicators in middle childhood. Participants were 608 twin children (MZ = 178, same-sex DZ = 234, opposite-sex DZ = 190) assessed at 8 years of age (SD = 0.63 years). Objective nighttime sleep duration, efficiency, sleep onset latency (SOL), midpoint time, and midpoint variability were collected from actigraph watches worn for 7 nights (Mnights = 6.83, SD = 0.62). Children's nighttime sleep duration and daytime sleepiness were assessed via parent report. Findings suggested high additive genetic influence on objective sleep quantity and quality, whereas objective SOL, sleep midpoint time, midpoint variability, parent-reported sleep duration, and daytime sleepiness were largely influenced by the shared environment. Common genetic factors explained associations between objective sleep quantity and quality, but genetics did not account for links with parent-reported sleep duration, midpoint time, or midpoint variability. Thus, objective and parent-reported assessments of children's sleep have unique genetic etiologies and should not be used interchangeably in the sleep literature.

Heritability of sleep duration and quality: A systematic review and meta-analysis

Epidemiological and interventional research has highlighted sleep as a potentially modifiable risk factor associated with poor physical and mental health. Emerging evidence from (behavioral) genetic research also shows that sleep characteristics are under strong genetic control. With this study we aimed to meta-analyze the literature in this area to quantify the heritability of sleep duration and sleep quality in the general population. We conducted a systematic literature search in five online databases on January 24th 2020. Two authors independently screened 5644 abstracts, and 160 complete articles for the inclusion criteria of twin studies from the general population reporting heritability statistics on sleep duration and/or quality, and written in English. We ultimately included 23 papers (19 independent samples: 45,328 twins between 6 mo and 88 y) for sleep duration, and 13 papers (10 independent samples: 39,020 twins between 16 and 95 y) for sleep quality. Collectively, we showed that 46% of the variability in sleep duration and 44% of the variability in sleep quality is genetically determined. The remaining variation in the sleep characteristics can mostly be attributed to the unique environment the twins experience, although the shared environment seemed to play a role for the variability of childhood sleep duration. Meta-analyzed heritability estimates for sleep duration, however, varied substantially with age (17% infancy, 20-52% childhood, 69% adolescence and 42-45% adulthood) and reporter (8% parent-report, 38-52% self-report). Heritability estimates for actigraphic and Polysomnography (PSG)-estimated sleep were based on few small samples, warranting more research. Our findings highlight the importance of considering genetic influences when aiming to understand the underlying mechanisms contributing to the trajectories of sleep patterns across the lifespan.

Sleep and social relationships in healthy populations: A systematic review

Over the past decade, research linking sleep and social relationships has burgeoned. Researchers across the globe are trying to understand whether the quality and quantity of our social relationships matter for sleep, and vice versa. We conducted a systematic review of the literature, identifying over 200 relevant articles examining sleep and social relationships in healthy populations. Here, we summarize our findings by reviewing 1) links between sleep and broad social ties across the lifespan, and 2) links between sleep and specific social relationships identified in the literature search, including romantic relationships, family relationships, and work relationships. Taken together, the literature provides evidence that the quality and presence of social relationships, especially our closest relationships, play a role in how we sleep. Likewise, sleep appears to influence our social bonds. However, the majority of work is correlational, limiting conclusions about the directionality of these effects. We conclude by synthesizing the findings, considering the limitations of the present literature, and identifying key future directions for this emerging area of research.