Frequent nightmares in children: familial aggregation and associations with parent-reported behavioral and mood problems

Behind closed eyes: Understanding nightmares in children and adolescents with autism spectrum disorder - A systematic review

INTRODUCTION

Brain and sleep development in childhood shapes emotional and cognitive growth, including the ability to recall dreams. In line with the continuity hypothesis of dreaming, several findings suggest a link between clinical symptoms and nightmare frequency. Sleep disorders and anxiety are among the most frequently co-occurring conditions in children and adolescents with autism spectrum disorder (ASD). However, their impact on nightmares has not yet been systematically explored. This review aims to address this research gap by investigating nightmares in autism and their influence on clinical symptoms and cognitive functioning.

METHODS

The literature was searched utilizing the databases PubMed, PsycINFO, Web of Science, and Scopus, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The included studies were assessed for methodological quality.

RESULTS

Twenty-nine papers were reviewed. The prevalence of nightmares occurring very frequently was below 5 %, with no significant difference in nightmare prevalence between children with ASD and their healthy peers. Furthermore, several findings reported a relationship between nightmares and other sleep disturbances among individuals with ASD.

DISCUSSION

The study of dreaming in ASD may provide valuable insights into the disorder. Although comorbid sleep disorders can influence nightmare frequency, the results of this review suggest that nightmares may not represent a distinctive feature of ASD. However, poor communication and introspection skills may explain the difficulties in reporting dream experiences. Given the preliminary nature of current research on nightmares in ASD, further studies are essential to overcome existing limitations and deepen our understanding.

The relationships between insomnia, nightmares, and dreams: A systematic review

Insomnia and nightmares are both prevalent and debilitating sleep difficulties. The present systematic review aims to document the relationships between insomnia and nightmares in individuals without a concomitant psychopathology. The relationships between insomnia and dreams are also addressed. PsycINFO and Medline were searched for papers published in English or French from 1970 to March 2023. Sixty-seven articles were included for review. Most results support positive relationships between insomnia variables and nightmare variables in individuals with insomnia, individuals with nightmares, the general population, students, children and older adults, and military personnel and veterans. These positive relationships were also apparent in the context of the COVID-19 pandemic. Some psychological interventions, such as Imagery Rehearsal Therapy, might be effective in alleviating both nightmares and insomnia symptoms. Regarding the relationships between insomnia and dreams, compared with controls, the dreams of individuals with insomnia are characterized by more negative contents and affects. The results show that insomnia and nightmares are connected and may be mutually aggravating. A model is proposed to explain how insomnia might increase the likelihood of experiencing nightmares, and how nightmares can in turn lead to sleep loss and nonrestorative sleep.

Middle childhood and adolescence sleep duration and behavior problems in adolescence

We examined the associations of middle childhood and adolescence nighttime sleep duration with adolescence internalizing and externalizing behavior problems per the Youth Self-Report (YSR) and the Child Behavior Checklist (CBCL) questionnaires, in a cohort of 889 Colombian schoolchildren. We estimated adjusted differences with 95% confidence intervals (CI) in mean behavior problem t-scores in standardized units between recommended sleep duration categories and as a continuous exposure using multiple linear regression and restricted cubic spline models, respectively. Compared with sleep duration within recommendations, middle childhood sleep above recommendations was related to 4.6 (95% CI: 1.6, 7.6; p = .004) and 5.4 (95% CI: 1.2, 9.7; p = .01) adjusted units higher YSR and CBCL externalizing problem scores, respectively. In continuous exposure analyses, this association seemed restricted to children aged ≥11 years. Longer sleep, both in categories and as a continuous exposure, was also associated with increased CBCL internalizing problems. Results did not differ by sex or weekend/weekday sleep. Sleeping under recommendations in middle childhood was not significantly related to behavior problems; nevertheless, shorter sleep in adolescence, in both categorical and continuous scales, was significantly related to behavior problems. In conclusion, behavior problems in adolescence are associated with longer sleep in middle childhood and shorter sleep in adolescence.

Associations between sleep problems and emotional/behavioural difficulties in healthy children and adolescents

OBJECTIVE

This study aimed to (1) characterise sleep disturbances and emotional/behavioural difficulties among healthy German children and adolescents aged 3 to 13 years, (2) examine the association between parent-reported sleep problems and emotional/behavioural difficulties, (3) point out possible relations between specific kinds of sleep disturbances and different behavioural difficulties.

METHODS

Data were collected between 2011 and 2015 within the LIFE Child study in Germany. The sample included 1101 3- to 13-year-old children and adolescents. Information on sleep disturbances-assessed via the Children's Sleep Habits Questionnaire (CSHQ), emotional/behavioural difficulties-assessed via the Strengths and Difficulties Questionnaire (SDQ), and socioeconomic status was provided by participants' parents. Multiple regressions were applied to analyse the associations between general and specific sleep disturbances (independent variables) and emotional/behavioural difficulties (dependent variables).

RESULTS

The total CSHQ score was positively associated with the total SDQ score and all SDQ subscales (emotional problems, conduct problems, hyperactivity/inattention, peer relationship problems). Most of the CSHQ subscales were related to SDQ subscale scores, except for a few non-significant relations with hyperactivity/inattention and conduct problems. The CSHQ total score, daytime sleepiness, sleep duration and parasomnias showed the strongest associations with the SDQ total score.

CONCLUSION

This study confirms an association between children's and adolescents' sleep habits and psychological health. We were able to demonstrate the association between sleep problems and emotional/behavioural difficulties in a large sample of healthy participants. In particular, we observed a significant relation between parasomnias and hyperactive/inattentive behaviour as well as a significant association between emotional problems and sleep problems, especially daytime sleepiness, sleep anxiety and parasomnias.

Problematic internet use and suicide ideation among Chinese adolescents: The indirect effects of insomnia, nightmares, and social jetlag

BACKGROUND

Problematic Internet use (PIU) is related to suicide ideation (SI) in adolescents, but little is known about the potential mechanisms between them. This study aimed to examine the mediation roles of insomnia, nightmares, and social jetlag in the association of PIU with SI in adolescents.

METHODS

A total of 39,731 adolescents (mean age = 13.49 ± 0.76 years, 54.4 % males) from Shenzhen, China, participated in a cross-sectional survey. SI was assessed using the ninth item of the Patient Health Questionnaire-9. PIU was measured by the Revised Chinese Internet Addiction Scale. A self-administered questionnaire was used to assess insomnia symptoms, nightmare frequency, social jetlag, sleep duration, psychological distress, and social-demographical characteristics. Logistic regression and path analyses were performed to examine the associations between PIU, insomnia symptoms, nightmares, social jetlag, and SI.

RESULTS

The prevalence of PIU and SI were 14.9 % and 18.6 %, respectively. PIU, insomnia symptoms, frequent nightmares, and social jetlag were significantly associated with SI. Path analyses showed that the indirect effects of PIU on SI through insomnia symptoms, frequent nightmares, and social jetlag were significant. Conversely, social jetlag significantly mediated the pathway from SI to PIU. The mediation effect sizes of these sleep and circadian problems were slightly larger in females than in males.

LIMITATIONS

Cross-sectional design limited the capacity to infer causal relationships.

CONCLUSIONS

The associations between PIU and SI were mediated by sleep and circadian problems. These findings underscore the importance of assessing and intervening in sleep and circadian problems among adolescents with PIU or SI.

Sleep Disturbances and Emotional and Behavioral Difficulties Among Preschool-Aged Children

Importance

Sleep disturbances and mental health problems are highly comorbid and bidirectionally correlated across childhood. The association between the natural history of sleep disturbances and the transition of mental health problems has not been quantified.

Objective

To examine the association between the natural history of sleep disturbances and resolved and incident emotional and behavioral difficulties (EBDs).

Design, Setting, and Participants

This cohort study used data from the Shanghai Children's Health, Education and Lifestyle Evaluation-Preschool (SCHEDULE-P), a prospective and population-based longitudinal cohort study of children enrolled in preschools in Shanghai, China, from November 10 to 24, 2016. A total of 20 324 children aged 3 to 4 years were recruited from the junior class of 191 kindergartens, of whom 17 233 (84.8%) participated in the 2-year follow-up. A multilevel regression model was used to evaluate the association between the development of sleep disturbances and the occurrence of resolved and incident EBDs. The data analysis spanned from August 4, 2021, to October 31, 2023.

Exposures

Sleep disturbances were assessed using the Children's Sleep Habit Questionnaire; EBDs were assessed using the Strengths and Difficulties Questionnaire.

Main Outcomes and Measures

Occurrence of incident and resolved EBDs at the 2-year follow-up.

Results

The cohort included 17 182 participants, with a mean (SD) age of 3.73 (0.29) years at enrollment; 52.0% were boys. The prevalence of EBDs at school entry and graduation years was 27.8% and 18.7%, respectively, while the prevalence of sleep disturbances was 41.3% and 31.5%, respectively. Among those with EBDs at the entry year, 35.0% maintained stability in the graduation year, while sleep disturbances were stable in 50.0% of those with sleep disturbances. After controlling for confounding factors, the odds ratio (OR) for resolved EBDs was lower in the incident sleep disturbance (ISD) group (OR, 0.50 [95% CI, 0.41-0.62]; P < .001) and stable sleep disturbance (SSD) group (OR, 0.47 [95% CI, 0.40-0.56]; P < .001) compared with the group with no sleep disturbances. The ORs for incident EBDs among the ISD group (OR, 2.58 [95% CI, 2.22-3.01]; P < .001) and SSD group (OR, 2.29, [95% CI, 1.98-2.64]; P < .001) were higher than among the group with no sleep disturbances.

Conclusions and Relevance

In this prospective cohort study, the natural history of sleep disturbances among preschool-aged children was associated with both resolved and incident EBDs. Routine screening and precise intervention for sleep disturbances may benefit the psychosocial well-being of this population.

Sleep-related items on the school-age CBCL and the PROMIS sleep disturbance 4-item short-form: A psychometric comparison from the Environmental Influences on Child Health Outcomes (ECHO) program

The Child Behavior Checklist (CBCL) parent-report school-age form, a broad instrument widely used to evaluate youth's emotional and behavioral functioning, includes seven sleep-related items. These items are not an official subscale of the CBCL, but researchers have used them as a measure of general sleep problems. The primary objective of the present study was to evaluate the construct validity of the CBCL sleep items with a validated measure of sleep disturbance, the Patient-Reported Outcomes Measurement Information System Parent Proxy Short Form-Sleep Disturbance 4a (PSD4a). To do so, we used coadministered data on the two measures from 953 participants ages 5-18 years in the National Institutes of Health Environmental influences on Child Health Outcomes research program. Exploratory factor analysis (EFA) revealed two CBCL items were strictly jointly unidimensional with the PSD4a. To help prevent floor effects, we conducted further analyses that revealed three additional CBCL items could be included as an ad hoc measure of sleep disturbance. However, the PSD4a remains a psychometrically superior measure of child sleep disturbance. Researchers using these CBCL items to measure child sleep disturbance should account for these psychometric issues in their analysis and/or interpretation. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Distressing dreams in childhood and risk of cognitive impairment or Parkinson's disease in adulthood: a national birth cohort study

Background

Distressing dreams in middle-aged and older adults have been associated with an increased risk of developing cognitive impairment (including dementia) and Parkinson's disease (PD). Whether distressing dreams in younger people might be associated with an increased risk of developing these conditions is unknown. This study investigated the association between distressing dreams in childhood and the risk of developing cognitive impairment or PD by age 50.

Methods

Data from the 1958 British Birth Cohort Study - a prospective birth cohort which included all people born in Britain during a single week in 1958, were used in this longitudinal analysis. Information on distressing dreams were obtained prospectively from the children's mothers at ages 7 (1965) and 11 (1969). Cognitive impairment and PD at age 50 (2008) were determined by cognitive assessment and doctor-diagnosis respectively. The association between distressing dreams at ages 7 and 11 (no time point, 1 time point, 2 time points) and cognitive impairment or PD at age 50, was evaluated using multivariable Firth logistic regression, with adjustment for potential confounders.

Findings

Among 6991 children (50.6% female) with follow-up available at age 50, 267 (3.8%) developed cognitive impairment or PD. After adjustment for all covariates, having more regular distressing dreams during childhood was linearly and statistically significantly associated with higher risk of developing cognitive impairment or PD by age 50 (P for trend = 0.037). Compared with children who never had distressing dreams (no time point), children who had persistent distressing dreams (2 time points) had an 85% increased risk of developing cognitive impairment or PD by age 50 (adjusted odds ratio = 1.85; 95% CI: 1.10, 3.11).

Interpretation

Having persistent distressing dreams during childhood may be associated with an increased risk of developing cognitive impairment or PD in adulthood. Future studies are needed to confirm these findings and to determine whether treating distressing dreams during early life may lower the risk of dementia and PD.

Funding

The study received no external funding.

Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias

STUDY OBJECTIVES

This pilot study determined whether transdiagnostic cognitive behavioral therapy for parasomnias (CBTp) reduces parasomnia and activity levels during sleep in a sample of adult sleep clinic outpatients. A secondary objective was to assess whether treatment produces improvements in daytime fatigue/sleepiness, perceived cognition, mood, and depression/anxiety/stress, as well as functional impairment in work and leisure activities.

METHODS

This was a randomized controlled trial with CBTp and self-monitoring control conditions. Participants were 19 adults with a DSM 5 parasomnia disorder who received individual CBTp virtually from their homes. CBTp consisted of psychoeducation, sleep hygiene and safety instructions, relaxation training, parasomnia techniques, and relapse prevention in a 6-week manualized, structured program.

RESULTS

Using a repeated measures analysis of variance model, and relative to a self-monitoring control condition, results showed that CBTp produced statistically significant improvements in parasomnia frequency, severity, nocturnal activity, and sleep efficiency. There was a trend toward reduced sleep-onset latency and improved work and social adjustment. Of treated participants, 100% rated themselves as improved at study conclusion.

CONCLUSIONS

Implications of these findings are that cognitive behavioral interventions for parasomnias are effective in lessening parasomnias. More investigation into this type of treatment is warranted.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Impact of Cognitive Behavioral Therapy on Parasomnias; URL: https://clinicaltrials.gov/ct2/show/NCT04633668; Identifier: NCT04633668.

CITATION

Vincent N, Dirkse D, Giannouli E, McQuarrie A. Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias. J Clin Sleep Med. 2023;19(3):499-509.

Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research

STUDY OBJECTIVES

This review aims to assess the association between socioeconomic status (SES) and sleep health in the general population and the mediating effects of lifestyle and mental and physical health in this relationship.

METHODS

Observational studies testing the independent association between objective or subjective SES indicators and behavioral/physiological or clinical sleep health variables in the general population were included. PubMed/MEDLINE was searched for reports published from January 1990 to December 2019. The direction of effect was used as the primary effect measure, testing the hypothesis that low SES is associated with poor sleep health outcomes. Results are presented in the form of direction effect plots and synthesized as binomial proportions.

RESULTS

Overall, 336 studies were identified. A high proportion of effects at the expected direction was noted for measures of sleep continuity (100% for sleep latency, 50-100% for awakenings, 66.7-100% for sleep efficiency), symptoms of disturbed sleep (75-94.1% for insomnia, 66.7-100% for sleep-disordered breathing, 60-100% for hypersomnia), and general sleep satisfaction (62.5-100%), while the effect on sleep duration was inconsistent and depended on the specific SES variable (92.3% for subjective SES, 31.7% for employment status). Lifestyle habits, chronic illnesses, and psychological factors were identified as key mediators of the SES-sleep relationship.

CONCLUSIONS

Unhealthy behaviors, increased stress levels, and limited access to health care in low-SES individuals may explain the SES-sleep health gradient. However, the cross-sectional design of most studies and the high heterogeneity in employed measures of SES and sleep limit the quality of evidence. Further research is warranted due to important implications for health issues and policy changes.

CITATION

Papadopoulos D, Etindele Sosso FA. Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research. J Clin Sleep Med. 2023;19(3):605-620.

The Effects of Pharmacological Treatment of Nightmares: A Systematic Literature Review and Meta-Analysis of Placebo-Controlled, Randomized Clinical Trials

Nightmares are highly prevalent and distressing for the sufferer, which underlines the need for well-documented treatments. A comprehensive literature review and meta-analysis of the effects of different pharmacological placebo-controlled randomized clinical trials, covering the period up to 1 December 2022, was performed. Searches were conducted in PubMed, Embase, Web of Science, PsychInfo, Cinahl, and Google Scholar, resulting in the identification of 1762 articles, of which 14 met the inclusion criteria: pharmacological intervention of nightmares, based on a placebo-controlled randomized trial published in a European language, reporting outcomes either/or in terms of nightmare frequency, nightmare distress, or nightmare intensity, and reporting sufficient information enabling calculation of effect sizes. Most studies involved the effect of the α1-adrenergic antagonist prazosin in samples of veterans or soldiers suffering from posttraumatic stress disorder. Other medications used were hydroxyzine, clonazepam, cyproheptadine, nabilone, and doxazosin. The vast majority of studies were conducted in the USA. The studies comprised a total of 830 participants. The Clinician-Administered PTSD Scale was the most frequently used outcome measure. The results showed an overall effect size of Hedges' g = 0.50 (0.42 after adjustment for publication bias). The synthetic cannabinoid nabilone (one study) showed the highest effect size (g = 1.86), followed by the histamine H1-antagonist hydroxyzine (one study), and prazosin (10 studies), with effect sizes of g = 1.17 and g = 0.54, respectively. Findings and limitations are discussed, and recommendations for future studies are provided.

The vision of dreams: from ontogeny to dream engineering in blindness

The mechanisms involved in the origin of dreams remain one of the great unknowns in science. In the 21st century, studies in the field have focused on 3 main topics: functional networks that underlie dreaming, neural correlates of dream contents, and signal propagation. We review neuroscientific studies about dreaming processes, focusing on their cortical correlations. The involvement of frontoparietal regions in the dream-retrieval process allows us to discuss it in light of the Global Workspace theory of consciousness. However, dreaming in distinct sleep stages maintains relevant differences, suggesting that multiple generators are implicated. Then, given the strong influence of light perception on sleep regulation and the mostly visual content of dreams, we investigate the effect of blindness on the organization of dreams. Blind individuals represent a worthwhile population to clarify the role of perceptual systems in dream generation, and to make inferences about their top-down and/or bottom-up origin. Indeed, congenitally blind people maintain the ability to produce visual dreams, suggesting that bottom-up mechanisms could be associated with innate body schemes or multisensory integration processes. Finally, we propose the new dream-engineering technique as a tool to clarify the mechanisms of multisensory integration during sleep and related mental activity, presenting possible implications for rehabilitation in sensory-impaired individuals. The Theory of Proto-consciousness suggests that the interaction of brain states underlying waking and dreaming ensures the optimal functioning of both. Therefore, understanding the origin of dreams and capabilities of our brain during a dreamlike state, we could introduce it as a rehabilitative tool.

CITATION

Vitali H, Campus C, De Giorgis V, Signorini S, Gori M. The vision of dreams: from ontogeny to dream engineering in blindness. J Clin Sleep Med. 2022;18(8):2051-2062.

Nightmare frequency and psychopathological problems in a large sample of Chinese adolescents

PURPOSE

Nightmares are common, especially in pediatric populations and psychiatric patients. Nightmares are associated with daytime distress and negative health outcomes. The data on the prevalence and psychopathological profiles of nightmares in Chinese adolescents are limited. This study examined age and gender differences in nightmare frequency and associated psychopathological problems in a large sample of Chinese adolescents.

METHODS

A total of 11,831 adolescent students (mean age = 14.9, 12-18 years) participated in the baseline survey of Shandong Adolescent Behavior and Health Cohort. Participants completed a self-administered questionnaire to report their nightmare frequency, trait anger, hopelessness, and multiple domains of behavioral/emotional problems. Univariate and multivariate analyses were performed to examine psychopathological problems in relation to nightmare frequency.

RESULTS

Of the sample, 45.2% reported having nightmares at least once in the past month and 7.9% at least once/week. Girls reported more frequent nightmares than boys. Nightmare frequency significantly declined with age for both boys and girls. Mean scores on trait anger, hopelessness, attention, internalizing problems, and externalizing problems significantly increased with nightmare frequency. Frequent nightmares (at least once/week) were significantly associated with 2-4-fold increased likelihood of behavioral/emotional problems after adjusting for adolescent and family covariates.

CONCLUSION

Nightmares are prevalent in Chinese adolescents. Frequent nightmares are associated with multiple domains of psychopathological problems. Assessment and intervention of frequent nightmares should be incorporated into routine clinical practice and mental health services in adolescents.

Sleep Complaints Among School Children

Sleep complaints are common among children. These include both night-time and daytime symptoms, such as trouble falling asleep, problems in maintaining sleep, snoring, and unusual events during sleep and daytime functioning impairment. However, sleep complaints in children are often overlooked and undertreated in clinical practice. Untreated sleep problems may further impact on children's development and will persist into adulthood in some cases. This review summarizes the common sleep complaints and disorders in school children, and provides an overview of the epidemiology, clinical features, consequences, and treatment of the sleep problems.

Socioeconomic inequalities in pediatric obstructive sleep apnea

STUDY OBJECTIVES

To examine the association between multiple measures of socioeconomic status (SES) and objectively measured obstructive sleep apnea (OSA) in a Canadian pediatric population.

METHODS

This was a cross-sectional study of 188 children (4-17 years, mean age 9.3 ± 3.5 years) prospectively recruited from two hospital sleep clinics in Canada, using multivariable-adjusted linear and logistic regression of five measures of SES including parental education, income, social class, geographic location, and perceived SES based on the MacArthur Scale of Subjective Social Status, assessed in relation to four polysomnographic OSA variables including apnea-hypopnea index, apnea index, mean oxygen saturation level, and oxygen desaturation index.

RESULTS

Overall, low household-level SES appeared to be associated with both frequency (apnea index ≥ 1 events/h) and severity (apnea-hypopnea index ≥ 5 events/h) of OSA in children, with maternal education showing the most consistent and significant associations. Specifically, children with mothers reporting less than high school education had nearly three times the odds of having OSA after controlling factors including body mass index (odds ratio 2.96 [95% confidence interval, 1.05-8.37]), compared to university-educated participants. Consistent associations were also observed for geographic location with less frequency and severity of OSA among nonurban children. Perceived SES was minimally inversely associated with our outcomes.

CONCLUSIONS

This cross-sectional, multicenter study demonstrated that SES factors are linked to the occurrence and severity of OSA in children. Results indicated the need to incorporate the screening of SES in the diagnostic process of pediatric OSA to provide more targeted intervention and patient-centered care.

CITATION

Park JW, Hamoda MM, Almeida FR, et al. Socioeconomic inequalities in pediatric obstructive sleep apnea. J Clin Sleep Med. 2022;18(2):637-645.

Nightmare Distress as a Risk Factor for Suicide Among Adolescents with Major Depressive Disorder

PURPOSE

Nightmare is common and is also independently implicated in suicide risk among the adolescent population. Adolescents with major depressive disorder (MDD) are at an increased risk of suicide. Therefore, comorbid nightmares may amplify suicide risk among this clinical population. This study aimed to explore the effects of nightmares on suicide risk among adolescents with MDD.

PATIENTS AND METHODS

Subjects were 499 outpatients aged 12-18 in four large psychiatric hospitals clinic of China, from January 1 to October 31, 2021. Simultaneously, we matched 499 healthy controls according to gender and age. All participants underwent affective state (depressive and anxiety symptoms) and sleep variable (nightmare frequency/distress, insomnia symptoms, and daytime sleepiness) evaluation as well as MDD diagnoses and determination of suicide risk by a fully structured diagnostic clinical interview.

RESULTS

Adolescents with MDD reported a higher incidence of frequent nightmares (at least one night per week) and level of nightmare distress than healthy controls (22.0% vs 6.1%; 28.85 ± 11.92 vs 17.30 ± 5.61). Over half of the patients with suicide risk (51.6%) experienced frequent nightmares compared with approximately one-third of those at a risk for suicide (30.7%). Patients with suicide risk scored scientifically higher on sleep variables, depressive and anxiety symptoms than those without the risk. Further logistic regression analysis indicated that female gender, junior grade, recurrent depressive episode, severe nightmare distress and severe depressive symptoms were independently and significantly associated with suicide risk.

CONCLUSION

Our study provided evidence that adolescents with MDD experienced a higher prevalence of frequent nightmares and suffered more nightmare distress. Nightmare distress is an independent risk factor for suicide risk.

Can sleep profiles predict autistic traits in siblings of children with autism spectrum disorder?

INTRODUCTION

As the prevalence of ASD (autism spectrum disorder) continues to rise, so does the need to evaluate the impact of associated difficulties on both the diagnosed child and the immediate family.

OBJECTIVES

The aim of the present study was to assess reports of sleep disturbance or abnormal sleep behaviours (sleep profiles) in the siblings of diagnosed autistic children (referred to throughout this study as high-risk siblings, or HR-sibs) and to determine if these sleep patterns correlated with evidence of disturbed sleep among their siblings who had full symptoms of autistic spectrum disorder.

MATERIAL AND METHODS

This case control cross-sectional study investigated 64 autistic children, 80 HR-sibs, and 80 typically developing children. Each study subject was assessed for sleep problems and autistic traits through the use of a sleep-wake diary, a school sleep habit survey, and a childhood autism spectrum test.

RESULTS

Children with autism spectrum disorders and their HR-sibs showed no significant differences regarding their sleep profiles. Typically, developing children had more middle insomnia than HR-sibs and had more wake latency.

CONCLUSION

Increased risks for sleep problems in children with autism and their HR-sibs emphasized the importance of early screening for sleep problems in children with autism and their siblings.

Socioeconomic status and sleep disturbances among pediatric population: a continental systematic review of empirical research

To this day, no consensus has been established on the definition and the conceptualization of the socioeconomic status (SES), since all the available studies on the relation between SES and health did not use the same conceptual framework and operationalization to assess SES. While literature reported that SES markers (such as income, social support networks, education, employment or occupation) influence the health of populations by shaping living conditions; empirical research does not tell us which SES markers affect more strongly the sleep components of the individuals, as well as which sleep disorders (SD) are affected and how. Even though several original studies have tried to assess how changes in socioeconomic status of parents may affect the psychosocial environment and mental health of an individual directly or through his community, no systematic reviews on the influence of SES on children's sleep are available. This systematic review make an update on the different measures of SES and sleep disturbances used for pediatric population across the different regions of the world. Recommendations for a future standardization of SES measures is proposed, for a better understanding of its influence on sleep disturbances.

Bad dreams, bedtime anxiety, and trait anxiety in school-aged children

Background and objectives

Occasional nightmares (distressing dreams that awaking the sleeper) and bad dreams (distressing dreams that do not awaking the sleeper) are very common in children and adolescents. About 5% of children experience frequent nightmares (once a week or more often) and the question arises as to what factors contribute to significant nightmare distress which is basic for diagnosing a nightmare disorder.

Materials and methods

A sample of 624 school-aged children (10–16 years; mean age 12.45 ± 1.33 years) completed a dream questionnaire and an anxiety inventory.

Results

About 11% of the participants reported frequent bad dreams; 3.5% reported frequent bedtime anxieties due to bad dreams. Similar to the findings in adults, distress due to bad dreams was not only related to bad dream frequency but also to trait anxiety—controlling for the direct effect of trait anxiety on bad dream frequency, i.e., bad dream frequency and trait anxiety contributed independently to bedtime anxiety due to bad dreams. In the exploratory part, the cultural background of the children’s parents showed only minor effects on bad dreams.

Conclusion

Similar to nightmare studies in adults, bad dream frequency and trait anxiety contributed independently to bad dream distress. Based on the current diagnostic criteria of the nightmare disorder, it would be interesting to have the opportunity to treat children with significant distress due to nightmares or bad dreams and study the long-term benefit—given that many adult nightmare sufferers reported that their nightmares started in childhood.

Disturbing Dreams and Psychosocial Maladjustment in Children: A Prospective Study of the Moderating Role of Early Negative Emotionality

Although frequent disturbing dreams, including bad dreams and nightmares, have been repeatedly associated with poor psychological well-being in adults, considerably less information exists on their psychosocial correlates in children. Recent empirical and theoretical contributions suggest that the association between disturbing dream frequency and psychosocial adaptation in children may differ as a function of children's negative emotionality. The current study assessed the moderating effect of very early negative emotionality (17 months of age) in the relation between disturbing dream frequency and psychosocial maladjustment (i.e., externalizing + internalizing behaviors) in a sample of 173 11-year-old children. Mixed-model analyses revealed that disturbing dream frequency was associated with some internalizing behaviors but that the association between disturbing dream frequency and most externalizing behaviors was moderated by early negative emotionality. The latter result indicates that the relation between disturbing dream frequency and externalizing behaviors was significant in 11-year-old children showing moderate negative emotionality early in life, but particularly strong in those children with high early negative emotionality. Whereas, a moderating effect of early negative emotionality was not found between disturbing dream frequency and internalizing behaviors, the findings highlight the more specific role of early emotional negativity as a developmental moderator for the link between disturbing dreams and externalizing behaviors in children. The results are discussed in light of recent models of disturbed dreaming production.

The factor structure, reliability and validity of the Chinese version of the Van Dream Anxiety Scale

BACKGROUND/PURPOSE

Dream emotions and contents are associated with psychological well-being. Dream disturbances, such as frequent nightmares and dream anxiety, are associated with a variety of psychopathological conditions. Therefore, it is important to consider nightmares and the resulting dream anxiety. To address this issue, the Van Dream Anxiety Scale (VDAS) was designed especially for measuring nightmare frequency and dream anxiety caused by frightening dreams. As a Chinese version of VDAS may be helpful in promoting study of nightmare and dream anxiety among Chinese population, in the current study, we sought to develop a Chinese version of the VDAS (CVDAS).

METHODS

We translated the VDAS into Chinese. To evaluate its validity and reliability, a sample of 1,081 Chinese college students from two universities answered the CVDAS, GAD-7, PHQ-9 and EPQ-R-N. Ninety of them answered the CVDAS twice. We also conducted exploratory factor analysis (EFA) to explore the structure of CVDAS.

RESULTS

Excellent internal consistency (Cronbach's alpha coefficient was 0.926), split-half reliability (equal-length Spearman-Brown coefficient was 0.938) and good test-retest reliability (the intraclass correlation coefficient was 0.942 and t=-1.478, P=0.143) of the CVDAS was presented. Exploratory factor analyses indicated a two-factor structure: sleep-related disturbances caused by nightmares and dysfunction caused by nightmares. Convergent and divergent validities were acceptable.

CONCLUSION

The CVDAS shows promise for the measurement of nightmare frequency and specific dream anxiety in Chinese population. Future study should confirm the reliability and validity in the clinical population and further improve this scale.

Frequent nightmares in Chinese patients undergoing methadone maintenance therapy: prevalence, correlates, and their association with functional impairment

PURPOSE

Nightmares are associated with many negative health outcomes; however, little is known about the characteristics of nightmares in heroin-dependent patients (HDPs). This study examined the prevalence and correlates of frequent nightmares (FNs) and their association with functional impairment in Chinese patients undergoing methadone maintenance therapy (MMT).

PATIENTS AND METHODS

In total, 603 Chinese HDPs from three MMT clinics in Wuhan, China, completed this survey. FNs were defined as reporting nightmares at least once a week. The Sheehan Disability Scale (ShDS) was used to assess the severity of functional impairment of patients. A standardized questionnaire was used to collect data on socio-demographics, drug use characteristics, physical health, mental health, and insomnia.

RESULTS

The prevalence of FNs in Chinese HDPs receiving MMT was 25.9%. Factors significantly associated with nightmares among MMT HDPs included an educational attainment of senior high school and above (OR=2.73, P<0.001), unemployment (OR=3.16, P<0.001), a history of re-education through forced labor (OR=3.14, P<0.001), injecting heroin before MMT (OR=3.62, P=0.002), a high dose of methadone (>70 mg/day) (OR=2.03, P=0.006), use of hypnotics (OR=1.91, P=0.044), the presence of hepatitis B virus core antibody (OR=4.63, P<0.001), pain (OR=3.20, P<0.001), anxiety (OR=2.06, P=0.039), and insomnia (OR=5.75, P<0.001). After controlling for potential confounders, nightmares were still significantly associated with a higher ShDS score (β=2.718, P=0.006).

CONCLUSION

FNs are prevalent among Chinese HDPs receiving MMT and significantly associated with functional impairment. Nightmares are a clinically relevant phenomenon in Chinese MMT clinics, which deserves more clinical and research attention.

Eveningness chronotype, insomnia symptoms, and emotional and behavioural problems in adolescents

OBJECTIVE

Eveningness tendency and insomnia are common in adolescents, but whether they have an independent or synergistic effect on the risk of psychopathology have remained undefined. The present study aimed to examine eveningness chronotype and insomnia symptoms in relation to mental health and emotional and behavioural problems in a community-based adolescent population.

METHODS

A total of 4948 adolescents (weighted mean age: 14.5 ± 1.8 years, weighted percentage of females: 48.9%) completed the measures. Insomnia was assessed by the Insomnia Severity Index (ISI), and chronotype preference was measured by the reduced version of the Morningness-Eveningness Questionnaire (MEQ). Emotional and behavioural problems and mental health were assessed by the Strengths and Difficulties Questionnaire (SDQ) and the General Health Questionnaire (GHQ-12), respectively. Potential confounders including demographic factors, pubertal status, general health, and sleep duration were controlled for in the analyses.

RESULTS

Insomnia symptoms were prevalent in evening-type adolescents (52% vs intermediate-type: 34.3%, morning-type: 18.0%, p < 0.001), especially two subtypes of insomnia symptoms, including difficulty initiating sleep and difficulty maintaining sleep. Eveningness and insomnia were independently associated with an increased risk of having emotional and behavioural problems (eveningness: adjusted odds ratio [AdjOR] = 1.88, 95% confidence interval [CI] = 1.61-2.19, p < 0.001; insomnia: AdjOR = 3.66, 95% CI = 2.73-4.91) as well as poor mental health in adolescents (eveningness: AdjOR = 1.25, 95% CI = 1.04-1.52, p < 0.001; insomnia: AdjOR = 3.63, 95% CI = 2.41-5.03).

CONCLUSIONS

Eveningness and insomnia symptoms are independently associated with the risk of psychopathology in adolescents. Our findings underscore the need to address both sleep and circadian factors in assessing and managing emotional and behavioural problems in the adolescent population.

Sleep Characteristics and Behavioral Problems Among Children of Alcoholics and Controls

BACKGROUND

Past research has indicated that both sleep difficulties and a parental history of alcoholism increase the risk of behavioral problems. But it is not known whether sleep difficulties differentially increase the risk of problem behaviors among children of alcoholics (COAs) and controls. We compared multiple measures of sleep and the relationships between sleep and behavioral problems in these 2 groups of children.

METHODS

One hundred and fifteen children aged 8 to 12 (67% COAs; 56% girls; M_age  = 10.85, SD_age  = 1.51) participated in this study. Data presented here were taken from Time 1 of a larger prospective study designed to understand the relationship between sleep and alcohol use. All participants were naïve to alcohol and other illicit drugs. Participants were asked to wear an actigraph watch on their nondominant wrist for 1 week. Parents completed the Pediatric Sleep Questionnaire and the Achenbach Child Behavior Checklist.

RESULTS

Parents of COAs were more likely to rate their children as overtired compared with parents of non-COAs. Structural equation modeling analyses focusing on overall internalizing and externalizing problems did not reveal any group differences on the relationships between sleep measures and behavioral problems. Regression analyses focusing on specific behavioral problems showed that longer total sleep time, parental ratings of "sleep more" and "sleep less" than other children interacted with COA status to predict specific behavioral problems.

CONCLUSIONS

Sleep difficulties and duration appear to be a general risk factor for behavioral problems in both COAs and non-COAs, yet the relationships between specific sleep parameters and behavioral problems appear to be different between the 2 groups.

Relationship between subtypes and symptoms of ADHD, insomnia, and nightmares in connection with quality of life in children

OBJECTIVES

This study examined the links between sleep disorders and subtypes of attention deficit-hyperactivity disorder (ADHD-inattention, ADHD-combined, ADHD-hyperactive/impulsive) in childhood. We set up a hypothetical model linking different symptoms of both disorders to construct the underlying and shared pathways. By examining a sample of children with ADHD we firstly tested parts of the model.

METHODS

A total of 72 children with symptoms of ADHD (aged 6-13 years; 79.2% boys) were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, fifth edition and the International Classification of Sleep Disorders, third edition in regards to ADHD and sleep disorders via standardized parent-rated questionnaires. Additionally, quality of life (QoL) was assessed. Overall, 46 children fulfilled the criteria of ADHD and were medication-naive.

RESULTS

On average, the whole sample had clinically elevated total scores of the Children's Sleep Habits Questionnaire in the validated German version (CSHQ-DE), indicating an increased prevalence of sleep disorders in children with ADHD. In accordance to our hypothetical model, children with primarily hyperactive-impulsive ADHD showed the highest CSHQ-DE scores. Moreover, we found a high impact for insomnia in this subgroup and a high comorbid load for the mutual occurrence of insomnia and nightmares. Furthermore, QoL was reduced in our whole sample, and again intensified in children with comorbid insomnia and nightmares.

CONCLUSION

We verified an elevated occurrence of sleep disorders in children with ADHD and were able to link them to specific subtypes of ADHD. These results were in line with our hypothetical model. Moreover, we found a clinically reduced QoL in mean for the whole sample, indicating the strong impact of ADHD in the lives of affected children, even intensified if children exhibited comorbid insomnia and nightmares. These results should be kept in mind regarding the treatment and therapy of this subgroup of children. Specific treatment strategies should be considered for these children.

Sleep Problems in Childhood and Borderline Personality Disorder Symptoms in Early Adolescence

Sleep disorders, such as insomnia and nightmares, are commonly associated with Borderline Personality Disorder (BPD) in adulthood. Whether nightmares and sleep-onset and maintenance problems predate BPD symptoms earlier in development is unknown. We addressed this gap in the literature using data from the Avon Longitudinal Study of Parents and Children (ALSPAC). Participants included 6050 adolescents (51.4 % female) who completed the UK Childhood Interview for DSM-IV BPD at 11 to 12 years of age. Nightmares and sleep onset and maintenance problems were prospectively assessed via mother report when children were 2.5, 3.5, 4.8 and 6.8 years of age. Psychopathological (i.e., emotional temperament; psychiatric diagnoses; and emotional and behavioural problems) and psychosocial (i.e., abuse, maladaptive parenting, and family adversity) confounders were assessed via mother report. In logistic regressions, persistent nightmares (i.e., regular nightmares at 3 or more time-points) were significantly associated with BPD symptoms following adjustment for sleep onset and maintenance problems and all confounders (Adjusted Odds Ratio = 1.62; 95 % Confidence Interval = 1.12 to 2.32). Persistent sleep onset and maintenance problems were not significantly associated with BPD symptoms. In path analysis controlling for all associations between confounders, persistent nightmares independently predicted BPD symptoms (Probit co-efficient [β] = 0.08, p = 0.013). Emotional and behavioural problems significantly mediated the association between nightmares and BPD (β =0.016, p < 0.001), while nightmares significantly mediated associations between emotional temperament (β = 0.001, p = 0.018), abuse (β = 0.015, p = 0.018), maladaptive parenting (β = 0.002, p = 0.021) and subsequent BPD. These findings tentatively support that childhood nightmares may potentially increase the risk of BPD symptoms in early adolescence via a number of aetiological pathways. If replicated, the current findings could have important implications for early intervention, and assist clinicians in the identification of children at risk of developing BPD.

Sleep Complaints as Risk Factor for Suicidal Behavior in Severely Depressed Children and Adolescents

Objectives

To investigate the association between sleep complaints and suicidal behaviors among severely depressed children and adolescents.

Methods

The sample was 214 youths (56.1% males, mean age 12.5 years) with diagnosis of DSM‐IV major depressive disorder consecutively recruited from a university‐based outpatient clinic specialized in mood disorders. The structured interview for children and adolescents was applied to participants. The Children's Depression Rating Scale—revised version—scored the severity of depression, and the Children's Global Assessment Scale assessed the global functioning. Subgroups of patients were compared for psychopathological association by means of logistic regression, in accordance with presence and absence of sleep complaints and suicidality.

Results

The frequency of sleep complaints and suicidal behaviors was, respectively, 66.4% and 52.3%, and both symptoms were observed in 37.9% of patients. Initial insomnia was the most frequent manifestation (58%), followed by night awakening (36%), daytime sleepiness (31%), and early awakening (29.9%). Significant association between sleep disturbance and suicidal behavior was found (odds ratio range of 2.3–10.8).

Conclusion

Sleep disturbances are potential warning manifestations of suicidal behaviors in depressed youth. Possibly, the severity of the active affective episode likely underlies in both sleep complaints and suicidal behaviors among depressed underage patients.

Help-seeking behaviors for insomnia in Hong Kong Chinese: a community-based study

OBJECTIVES

To determine the prevalence and correlates of help-seeking behaviors for insomnia in Hong Kong Chinese middle-aged adults and their offspring.

METHODS

A total of 2231 middle-aged adults (54.2% females, mean age 45.8 years) and 2186 children and adolescents (51.9% females, mean age 13.4 years) completed a questionnaire on insomnia symptoms, daytime functioning, health condition and treatments sought for insomnia.

RESULTS

A total of 40% of adults and 10% of children and adolescents with insomnia reported having sought treatment for insomnia. Conventional Western medicine was the commonly preferred treatment in 33.3% of adults and 13.3% of children and adolescents who sought help for insomnia, while a higher proportion of individuals with insomnia (34.5% of adults and 26.7% of children and adolescents) sought help from complementary and alternative medicine (CAM) therapies. Female gender (odds ratio [OR] [95% confidence interval, CI] = 2.14 [1.01-4.53]), higher family income (≥15,000 HKD/month) (OR [95% CI] = 3.15 [1.27-6.34]), severity of insomnia (Insomnia Severity Index ≥14) (OR [95% CI] = 2.12 [1.10-4.12]), chronic medications (OR [95% CI] = 4.71 [2.27-9.79]), and psychiatric disorders (OR [95% CI] = 2.83 [1.01-7.96]) were associated with help-seeking behaviors in adults. Presence of morning headache was associated with help-seeking behaviors in children and adolescents (OR [95% CI] = 8.66 [1.72-43.70]).

CONCLUSIONS

It is uncommon for Hong Kong Chinese to seek help for insomnia, despite the high prevalence of insomnia. The significant unmet need argues for timely intervention to promote sleep-health literacy and to enhance the awareness and accessibility of evidence-based treatment for insomnia.

Nightmares: risk factors among the Finnish general adult population

STUDY OBJECTIVES

To identify risk factors for experiencing nightmares among the Finnish general adult population. The study aimed to both test whether previously reported correlates of frequent nightmares could be reproduced in a large population sample and to explore previously unreported associations.

DESIGN

Two independent cross-sectional population surveys of the National FINRISK Study.

SETTING

Age- and sex-stratified random samples of the Finnish population in 2007 and 2012.

PARTICIPANTS

A total of 13,922 participants (6,515 men and 7,407 women) aged 25-74 y.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Nightmare frequency as well as several items related to socioeconomic status, sleep, mental well-being, life satisfaction, alcohol use, medication, and physical well-being were recorded with a questionnaire. In multinomial logistic regression analysis, a depression-related negative attitude toward the self (odds ratio [OR] 1.32 per 1-point increase), insomnia (OR 6.90), and exhaustion and fatigue (OR 6.86) were the strongest risk factors for experiencing frequent nightmares (P < 0.001 for all). Sex, age, a self-reported impaired ability to work, low life satisfaction, the use of antidepressants or hypnotics, and frequent heavy use of alcohol were also strongly associated with frequent nightmares (P < 0.001 for all).

CONCLUSIONS

Symptoms of depression and insomnia were the strongest predictors of frequent nightmares in this dataset. Additionally, a wide variety of factors related to psychological and physical well-being were associated with nightmare frequency with modest effect sizes. Hence, nightmare frequency appears to have a strong connection with sleep and mood problems, but is also associated with a variety of measures of psychological and physical well-being.

Ontogeny of dreaming: a review of empirical studies

The examination of children's sleep-related mental experiences presents many significant challenges for researchers investigating the developmental trajectories of human dreaming. In contrast to the well-explored developmental patterns of human sleep, data from dream research are strikingly divergent with highly ambiguous results and conclusions, even though there is plenty of indirect evidence suggesting parallel patterns of development between neural maturation and dreaming. Thus results from studies of children's dreaming are of essential importance not only to enlighten us on the nature and role of dreaming but to also add to our knowledge of consciousness and cognitive and emotional development. This review summarizes research results related to the ontogeny of dreaming: we critically reconsider the field, systematically compare the findings based on different methodologies, and highlight the advantages and disadvantages of methods, arguing in favor of methodological pluralism. Since most contradictory results emerge in connection with descriptive as well as content related characteristics of young children's dreams, we emphasize the importance of carefully selected dream collection methods. In contrast nightmare-related studies yield surprisingly convergent results, thus providing strong basis for inferences about the connections between dreaming and cognitive emotional functioning. Potential directions for dream research are discussed, aiming to explore the as yet unraveled correlations between the maturation of neural organization, sleep architecture and dreaming patterns.

Restless legs symptoms in adolescents: epidemiology, heritability, and pubertal effects

AIMS

We aimed to determine the prevalence, pubertal effect, familial aggregation, and heritability of restless legs (RLS) symptoms in Chinese adolescents. In addition, the correlates and consequences of RLS symptoms were examined.

METHODS

This was a population-based family study that involved 1549 adolescents (probands), their parents and siblings. RLS symptoms were assessed by a single question measuring the core features of RLS. Subjects with RLS symptoms for at least once per week were considered as abnormal. Impairment of daytime functions, behavioral problems, health status, and lifestyle practice were also documented.

RESULTS

The prevalence of RLS symptoms was 2.8% in adolescents and 7.4% in their parents with female preponderance. Gender difference of RLS symptoms emerged in mid-pubertal adolescents (Tanner stage 3 or above). RLS symptoms were closely associated with various sleep problems (range of ORs=2.24 to 32.5, p<0.05), except habitual snoring. They were also independently associated with impairment of daytime functions, poor general health and frequent temper outbursts but not caffeine or alcohol intake or cigarette smoking after adjustment for age, sex, and other comorbid sleep problems. RLS symptoms presented with a modest familial aggregation and heritability (h²±SE=0.17±0.04, p<0.001).

INTERPRETATION

RLS symptoms are common in Chinese adolescents with significant health repercussions. Puberty plays a critical role in the emergence of gender difference of RLS symptoms, which are accounted for by both genetic and environmental factors.

Nightmares: Prevalence among the Finnish General Adult Population and War Veterans during 1972-2007

STUDY OBJECTIVES

To investigate the prevalence of nightmares among the Finnish general adult population during 1972-2007 and the association between nightmare prevalence and symptoms of insomnia, depression, and anxiety in World War II veterans.

DESIGN

Eight independent cross-sectional population surveys of the National FINRISK Study conducted in Finland in 1972, 1977, 1982, 1987, 1992, 1997, 2002, and 2007.

SETTING

Epidemiologic.

PARTICIPANTS

A total of 69,813 people (33,811 men and 36,002 women) age 25-74 years.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

The investigation of nightmare prevalence and insomnia, depression, and anxiety symptoms was based on questionnaires completed by the participants. Among the whole sample, 3.5% of the men and 4.8% of the women reported frequent nightmares (P < 0.0001 for sex difference), but the prevalence was affected by the age of participants and the year of the survey. Nightmare prevalence increased with age, particularly among the men. The number of people reporting occasional nightmares increased roughly by 20% for both sexes from 1972 to 2007 (P < 0.0001). Participants with war experiences reported more frequent nightmares and symptoms of insomnia, depression, and anxiety than participants without such experiences (P < 0.0001).

CONCLUSIONS

Prevalence of nightmares was affected by the sex and age of the participants, and occasional nightmares have become more common in Finland. Exposure to war elevates nightmare prevalence as well as insomnia, depression, and anxiety symptoms even decades after the war; large numbers of war veterans can affect nightmare prevalence on population level.

CITATION

Sandman N; Valli K; Kronholm E; Ollila HM; Revonsuo A; Laatikainen T; Paunio T. Nightmares: prevalence among the Finnish general adult population and war veterans during 1972-2007. SLEEP 2013;36(7):1041-1050.

Nightmares in the bedroom of science: mapping of a neglected sleep disorder

Nightmares are intense and unpleasant dream experiences that characterize approximately 4 percent of the adult population at least on a weekly basis. Nightmare frequency is often co-morbid with other mental complaints; however, recent results indicate that nightmare disorder is independent from waking mental dysfunctions. Nightmare disorder is intimately related to poor subjective sleep quality, and according to polysomnographic studies nightmare subjects’ sleep is characterized by increased sleep fragmentation and hyper-arousal. These findings suggest that instead of the psychopathological perspective nightmare disorder should be viewed as a specific sleep disorder that requires targeted treatment. Nevertheless, in order to choose the adequate treatment procedure clinicians should examine the co-morbid mental disorders as well taking into consideration the severity of nightmare distress, the latter supposed to be the mediator between nightmare frequency and waking mental dysfunctions. Orv. Hetil., 2013, 154, 497–502.

Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern

STUDY OBJECTIVES

Nightmares are disturbing mental experiences during sleep that usually result in abrupt awakenings. Frequent nightmares are associated with poor subjective sleep quality, and recent polysomnographic data suggest that nightmare sufferers exhibit impaired sleep continuity during nonrapid eye movement (NREM) sleep. Because disrupted sleep might be related to abnormal arousal processes, the goal of this study was to examine polysomnographic arousal-related activities in a group of nightmare sufferers and a healthy control group.

DESIGN

Sleep microstructure analysis was carried out by scoring the cyclic alternating pattern (CAP) in NREM sleep and the arousal index in rapid eye movement (REM) sleep on the second night of the polysomnographic examination.

SETTING

Hospital-based sleep research laboratory.

PARTICIPANTS

There were 17 in the nightmare (NMs) group and 23 in the healthy control (CTLs) group.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

The NMs group exhibited reduced amounts of CAP A1 subtype and increased CAP A2 and A3 subtypes, as well as longer duration of CAP A phases in comparison with CTLs. Moreover, these differences remained significant after controlling for the confounding factors of anxious and depressive symptoms. The absolute number and frequency of REM arousals did not differ significantly between the two groups.

CONCLUSIONS

The results of our study indicate that NREM sleep microstructure is altered during nonsymptomatic nights of nightmares. Disrupted sleep in the NMs group seems to be related to abnormal arousal processes, specifically an imbalance in sleep-promoting and arousing mechanisms during sleep.

CITATION

Simor P; Bódizs R; Horváth K; Ferri R. Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern. SLEEP 2013;36(3):413-419.

Personal characteristics related to the risk of adolescent internet addiction: a survey in Shanghai, China

Background

Paralleling the rapid growth in computers and internet connections, adolescent internet addiction (AIA) is becoming an increasingly serious problem, especially in developing countries. This study aims to explore the prevalence of AIA and associated symptoms in a large population-based sample in Shanghai and identify potential predictors related to personal characteristics.

Methods

In 2007, 5,122 adolescents were randomly chosen from 16 high schools of different school types (junior, senior key, senior ordinary and senior vocational) in Shanghai with stratified-random sampling. Each student completed a self-administered and anonymous questionnaire that included DRM 52 Scale of Internet-use. The DRM 52 Scale was adapted for use in Shanghai from Young’s Internet Addiction Scale and contained 7 subscales related to psychological symptoms of AIA. Multiple linear regression and logistic regression were both used to analyze the data.

Results

Of the 5,122 students, 449 (8.8%) were identified as internet addicts. Although adolescents who had bad (vs. good) academic achievement had lower levels of internet-use (p < 0.0001), they were more likely to develop AIA (odds ratio 4.79, 95% CI: 2.51-9.73, p < 0.0001) and have psychological symptoms in 6 of the 7 subscales (not in Time-consuming subscale). The likelihood of AIA was higher among those adolescents who were male, senior high school students, or had monthly spending >100 RMB (all p-values <0.05). Adolescents tended to develop AIA and show symptoms in all subscales when they spent more hours online weekly (however, more internet addicts overused internet on weekends than on weekdays, p < 0.0001) or when they used the internet mainly for playing games or real-time chatting.

Conclusions

This study provides evidence that adolescent personal factors play key roles in inducing AIA. Adolescents having aforementioned personal characteristics and online behaviors are at high-risk of developing AIA that may compound different psychological symptoms associated with AIA. Spending excessive time online is not in itself a defining symptom of AIA. More attention is needed on adolescent excessive weekend internet-use in prevention of potential internet addicts.

Disturbed dreaming and sleep quality: altered sleep architecture in subjects with frequent nightmares

Nightmares are intense, emotionally negative mental experiences that usually occur during late-night sleep and result in abrupt awakenings. Questionnaire-based studies have shown that nightmares are related to impaired sleep quality; however, the polysomnographic profile of nightmare subjects has been only scarcely investigated. We investigated the sleep architecture of 17 individuals with frequent nightmares and 23 control subjects based on polysomnographic recordings of a second night spent in the laboratory after an adaptation night. Nightmare subjects in comparison with control subjects were characterized by impaired sleep architecture, as reflected by reduced sleep efficiency, increased wakefulness, a reduced amount of slow wave sleep, and increased nocturnal awakenings, especially from Stage 2 sleep. While these differences were independent of the effects of waking psychopathology, nightmare subjects also exhibited longer durations of REM sleep that was mediated by heightened negative affect. Our results support that nightmares are related to altered sleep architecture, showing impaired sleep continuity and emotion-related increase in REM propensity.

Residual sleep disturbances in patients remitted from major depressive disorder: a 4-year naturalistic follow-up study

STUDY OBJECTIVES

To investigate the prevalence and clinical, psychosocial, and functional correlates of residual sleep disturbances in remitted depressed outpatients.

DESIGN

A 4-yr prospective observational study in a cohort of psychiatric outpatients with major depressive disorder was conducted with a standardized diagnostic psychiatric interview and a packet of questionnaires, including a sleep questionnaire, Hospital Anxiety and Depression Scale, NEO personality inventory, and Short Form-12 Health Survey.

SETTINGS

A university-affiliated psychiatric outpatient clinic.

INTERVENTIONS

N/A MEASUREMENTS AND RESULTS: Four hundred twenty-one depressed outpatients were recruited at baseline, and 371 patients (mean age 44.6 ± 10.4 yr, female 81.8%; response rate 88.1%) completed the reassessments, in which 41% were classified as remitted cases. One year prevalence of frequent insomnia at baseline and follow-up in remitted patients was 38.0% and 19.3%, respectively. One year prevalence of frequent nightmares at baseline and follow-up was 24.0% and 9.3%, respectively. Remitted patients with residual insomnia were more likely to be divorced (P < 0.05) and scored higher on the anxiety subscale (P < 0.05). Remitted patients with residual nightmares were younger (P < 0.05) and scored higher on neuroticism (P < 0.05) and anxiety subscales (P < 0.01). Residual insomnia and nightmares were associated with various aspects of impaired quality of life. Residual nightmares was associated with suicidal ideation (odds ratio = 8.40; 95% confidence interval 1.79-39.33).

CONCLUSIONS

Residual sleep disturbances, including insomnia and nightmares, were commonly reported in remitted depressed patients with impaired quality of life and suicidal ideation. A constellation of psychosocial and personality factors, baseline sleep disturbances, and comorbid anxiety symptoms may account for the residual sleep disturbances. Routine assessment and management of sleep symptoms are indicated in the integrated management of depression.

Does rapid eye movement sleep behavior disorder exist in psychiatric populations? A clinical and polysomnographic case-control study

OBJECTIVES

Rapid eye movement (REM) sleep behavior disorder (RBD) has been increasingly reported in patients with psychiatric disorders (pRBD). Although a close association with the usage of psychotropics has been postulated, it remains elusive whether psychotropics are the only causative factor of RBD symptoms in psychiatric populations. Moreover, there is limited literature documenting and quantifying the clinical and polysomnographic features in this population.

METHODS

A case-control study comparing the clinical and polysomnographic features of 31 pRBD patients with: (1) Age-, sex-, and psychiatric diagnoses-matched controls; and (2) Typical idiopathic RBD (tRBD) patients.

RESULTS

Despite being prescribed with similar psychotropics, pRBD patients had more dream-enacting behaviors (p<0.01), sleep-related injuries (p<0.01), and nightmares (p<0.01) than the psychiatric controls. pRBD patients were younger with more females, but they had comparable sleep-related injuries to tRBD. Both tRBD and pRBD had more REM-related muscle activity than controls (p<0.01) and the effect remained significant after adjusting for age, gender, and use of antidepressants.

CONCLUSIONS

Our study suggests that pRBD had comparable clinical features and consequences to those of tRBD. The occurrence of RBD symptoms in these patients may be related to a constellation of factors, including individual predisposition, depressive illness, antidepressants, and other clinical factors. Given the association of RBD and neurodegeneration in tRBD, further prospective follow-up of these patients is warranted.

Familial aggregation and heritability of insomnia in a community-based study

BACKGROUND

Emerging data suggested a significant familial aggregation of insomnia. We aimed to clarify the familial aggregation and heritability of insomnia disorder by using structural clinical interviews for the ascertainment of insomnia and psychiatric disorders in a community-based sample.

METHODS

Seventy-five adolescents with insomnia and their 180 first degree relatives, together with 141 age- and sex-matched non-insomnia controls and their 382 first degree relatives, were recruited. Each subject underwent a structured clinical interview and completed a series of psychometric inventories. The rates of insomnia disorder among the first degree relatives were employed to analyze familial aggregation. Heritability of insomnia was analyzed by SOLAR program as based on father-mother-offspring trios.

RESULTS

Our study confirmed a significant familial aggregation of insomnia with a first degree relatives' recurrence risk of 2.33 for current insomnia and 2.82 for lifetime insomnia, respectively. The heritability±SE of current and lifetime insomnia disorder was 0.48±0.13 and 0.61±0.11 (p<0.001), respectively, which were higher than insomnia symptoms as estimated by the Insomnia Severity Inventory (h(2)±SE=0.27±0.09) and the Pittsburgh Sleep Quality Index (h(2)±SE=0.30±0.11). After exclusion of comorbid psychiatric disorders, the heritability for current and lifetime primary insomnia was 0.45±0.17 (p=0.007) and 0.58±0.21 (p=0.004), respectively.

CONCLUSIONS

Our study demonstrates a significant familial aggregation with a high heritability of insomnia disorder. The strong heritability of insomnia persists despite the exclusion of psychiatric disorders. Further molecular genetic investigation of insomnia is indicated.

Insomnia, sleep quality, pain, and somatic symptoms: sex differences and shared genetic components

This study investigated the sex differences, and the shared genetic and environmental factors underlying the associations of sleep disturbances (insomnia and sleep quality) with pain and somatic symptoms in both adolescents and middle-aged adults. We recruited 259 adolescents (69 with current insomnia) and their parents (256 middle-aged adults, 78 with current insomnia). Insomnia severity and sleep quality were measured by the Insomnia Severity Inventory (ISI) and Pittsburgh Sleep Quality Index (PSQI), respectively. Pain and somatic symptoms were measured by the Somatic Symptom Inventory and Visual Analogue Scale for overall pain. Subjects with insomnia scored higher on all measures of pain and somatic symptoms than non-insomnia patients, in both adolescents and adults (P<.001). Both pain and somatic measures were associated with ISI and PSQI scores after controlling for age, sex, depressive and anxiety symptoms. There was an interaction effect between insomnia and female sex on pain and somatic symptoms (P<.05), especially in adults. Pain and somatic symptoms ran in family with moderate heritability (range h(2)=0.15-0.42). The phenotypic associations of ISI and PSQI with pain and somatic measures were both contributed by genetic (range p(G)=0.41-0.96) and environmental (range p(E)=0.27-0.40) factors with a major genetic contribution. In summary, insomnia and poor sleep quality are closely associated with pain and somatic symptoms. Insomnia seems to modulate the sex differences in pain and somatic symptoms, especially in the adult population. A shared genetic predisposition might underlie the associations of insomnia and sleep quality with pain and somatic symptoms.