Polysomnography-Detected Bruxism in Children is Associated With Somatic Complaints But Not Anxiety

Global Prevalence of Sleep Bruxism and Awake Bruxism in Pediatric and Adult Populations: A Systematic Review and Meta-Analysis

Background/Objectives: The purpose of this systematic review was to assess the global prevalence of sleep bruxism and awake bruxism in pediatric and adult populations. Methods: This systematic review was conducted by analyzing studies published from 2003 to 2023. The following keyword combination was utilized: prevalence, epidemiology, population, and bruxism. The PubMed database was analyzed, supplemented by manual searches using the Google search. Additionally, the snowballing procedure method was applied. A double assessment of the quality of publications was carried out to preserve the highest possible quality of evidence (e.g., Joanna Briggs Institute critical appraisal checklist). Analyses were conducted using the R statistical language. Results: The global bruxism (sleep and awake) prevalence is 22.22%. The global sleep bruxism prevalence is 21% and awake prevalence is 23%. The occurrence of sleep bruxism, based on polysomnography, was estimated at 43%. The highest prevalence of sleep bruxism was observed in North America at 31%, followed by South America at 23%, Europe at 21%, and Asia at 19%. The prevalence of awake bruxism was highest in South America at 30%, followed by Asia at 25% and Europe at 18%. Conclusions: One in four individuals may experience awake bruxism. Bruxism is a significant factor among women. It was observed that age is a significant factor for the occurrence of sleep bruxism in women. Among the limitations of the study is the lack of analysis of the prevalence of bruxism in Africa and Australia due to not collecting an adequate sample for analysis. The study was registered in the Open Science Framework (10.17605/OSF.IO/ZE786).

Genetics and sleep bruxism: a systematic review and meta-analysis of studies with twins

OBJECTIVE

To systematically review the literature regarding the concordance of sleep bruxism (SB) between monozygotic (MZ) and dizygotic (DZ) twins.

METHODS

The registration for this systematic review was accomplished in the International Prospective Register of Systematic Reviews (PROSPERO, No. CRD42021251751). As of July 2022, four databases were searched, including PubMed, Scopus, Embase, and Web of Science, as well as the grey literature in Google Scholar and OpenGrey. Observational studies evaluating SB in MZ and DZ twins of any age and sex were included. For the evaluation of the risk of bias, the Joanna Briggs checklist was utilized. The certainty of evidence was assessed via the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Pooled and subgroup meta-analyses were performed to estimate concordance of SB ​​between twins (p < 0.05).

RESULTS

In total, 3,155 records were identified. In the qualitative analysis, eleven studies were included; of these, seven were included in the meta-analysis. The majority of the articles exhibited a low risk of bias (63.6%). Greater SB concordance was observed between MZ twins than between DZ twins in the analysis of general concordance (OR = 1.47; 95% CI = 1.07-2.02) and also positive concordance (OR = 1.53; 95% CI = 1.29-1.81). Within the subgroup analyses, the significance of the findings remained only for the reported/self-reported SB regarding general concordance (OR = 1.44; 95% CI = 1.07-1.95) and positive concordance (OR = 1.55; 95% CI = 1.28-1.88). Low certainty of the evidence was observed for the general concordance analysis, while moderate certainty was observed for the positive concordance.

CONCLUSION

There was a higher concordance of SB in MZ twins compared to DZ twins, indicating a possible genetic influence on the condition's occurrence.

Bruxism in a Child with Trisomy 21 (Down Syndrome)-Case Report

Bruxism has been defined in recent years and analyzed in detail as the repetitive activity of the muscles of the masticatory system. Both adults and children experience two different forms of bruxism: daytime and nighttime bruxism. According to the WHO, bruxism affects 5% to 50% of the world's pediatric population. The symptoms of this disease include tooth wear and fractures, temporomandibular disorders, headaches, behavioral and sleep disorders, and parafunctional habits such as nail biting. According to scientists, psychosocial factors are the most likely factors causing bruxism in children. To this day, we do not have established standards of treatment for children, especially for those with disabilities. The issue of bruxism in children with Down syndrome (DS) is still unexplained. Anatomical abnormalities in the facial skeleton, reduced muscle tone, personality traits, and sleep problems in these people may cause the symptoms of bruxism. Our study aimed to present a clinical case of a 13-year-old girl with DS and symptoms of bruxism. Diagnostics and dental examination in children with intellectual disabilities and a lack of understanding of the disease create a great challenge for the treatment team, including the dentist, physiotherapist, psychologist, and family. Creating standards for treating and preventing bruxism symptoms is demanding, among other things, due to the lack of sufficient scientific research.

Attitude of Italian dental practitioners toward bruxism assessment and management: A survey-based study

INTRODUCTION

Bruxism is a spectrum of masticatory muscles activities. According to the recent evidence and international consensus, there is no indication to treat bruxism unless clinical consequences are present. The aim of the present study was to investigate the approach of Italian dentists to bruxism in their clinical practice.

METHODS

An anonymous online survey was developed, composed by 26 items grouped into five sections: (1) Characteristics of the respondent (Q1-Q6); (2) Bruxism frequencies (Q7-Q11); (3) Bruxism assessment (Q12-Q15); (4) Bruxism management (Q16-Q20); (5) Occlusal splints therapy (Q21-Q26).

RESULTS

A total of 384 practitioners, including specialists and non-specialists, participated in this survey. The majority of the respondents reported that 1-3 out of ten patients presented with bruxism. The diagnosis is mainly performed with non-instrumental methods, and facial pain and dental wear are the major clinical consequence associated with bruxism. Almost the entire sample of respondents report to offer occlusal splints to bruxism patients, and 41% refer to perform occlusal adjustments. Almost half of the respondents have never proposed any form of cognitive-behavioural therapy.

CONCLUSION

The results of the current survey highlighted several inconsistencies in Italian dentists' approaches to bruxism, suggesting the need for better education of practitioners and for the development of a standardized protocol to assess and manage bruxism in dental practices.

Sleep architecture as a candidate for phenotyping sleep bruxism: A narrative physiological review

BACKGROUND

Sleep bruxism (SB), an oral behaviour in otherwise healthy individuals, is characterised by frequent rhythmic masticatory muscle activity (RMMA) during sleep. RMMA/SB episodes occur over various sleep stages (N1-N3 and rapid eye movement (REM)), sleep cycles (non-REM to REM), and frequently with microarousals. It currently remains unclear whether these characteristics of sleep architecture are phenotype candidates for the genesis of RMMA/SB.

OBJECTIVES

This narrative review investigated the relationship between sleep architecture and the occurrence of RMMA as a SB phenotype candidate.

METHODS

PubMed research was performed using keywords related to RMMA/SB and sleep architecture.

RESULTS

In non-SB and SB healthy individuals, RMMA episodes were most frequent in the light non-REM sleep stages N1 and N2, particularly during the ascending phase of sleep cycles. The onset of RMMA/SB episodes in healthy individuals was preceded by a physiological arousal sequence of autonomic cardiovascular to cortical activation. It was not possible to extract a consistent sleep architecture pattern in the presence of sleep comorbidities. The lack of standardisation and variability between subject complexified the search for specific sleep architecture phenotype(s).

CONCLUSION

In otherwise healthy individuals, the genesis of RMMA/SB episodes is largely affected by oscillations in the sleep stage and cycle as well as the occurrence of microarousal. Furthermore, a specific sleep architecture pattern cannot be confirmed in the presence of sleep comorbidity. Further studies are needed to delineate sleep architecture phenotype candidate(s) that contribute to the more accurate diagnosis of SB and treatment approaches using standardised and innovative methodologies.

Correlations between sleep architecture and sleep-related masseter muscle activity in children with sleep bruxism

BACKGROUND

Sleep bruxism (SB) occurring during No-REM (nREM) sleep and increase in microarousals per hour have been described in adults, but not in children.

OBJECTIVE

To assess the correlation between sleep architecture and masseter muscle activity related to sleep bruxism (SB/MMA) in children.

MATERIALS AND METHODS

Forty-three children aged 7-12 years (mean age: 9.4 ± 1.3) with confirmed SB underwent a two-night polysomnographic (PSG) study in a sleep laboratory, for accommodation (first night) and data collection (second night). Data on sleep architecture (total sleep duration (TSD), sleep efficiency (SE), sleep onset latency (SOL), REM and nREM sleep duration and proportion and microarousals/hour during REM and nREM sleep) and episodes/hour of SB/MMA were recorded. Single and multiple-variable linear regression analyses were performed to assess the correlation between data on sleep architecture (predictors) and SB/MMA (dependent variable).

RESULTS

Shorter TSD, REM and nREM stage 1 sleep duration, longer SOL and more microarousals/hour during REM and nREM sleep were found to be positive predictors of SB/MMA in children in the multiple-variable regression analysis (R2  = 0.511).

CONCLUSION

Within the limitations of this study, it can be concluded that SB/MMA is correlated with altered sleep architecture in children (shorter total sleep duration (TSD), shorter nREM and REM sleep and higher microarousals during REM and nREM sleep). Nevertheless, the clinical significance of these findings need to be demonstrated in future studies.

Sleep bruxism in children and adolescents-A scoping review

BACKGROUND AND OBJECTIVE

This review paper focuses on sleep bruxism (SB) in children and adolescents. It aims to assess the landscape of knowledge published in the last 20 years.

METHODS

A total of 144 relevant publications from 386 previously identified through Medline were included, of which 83 were on possible SB, 37 on probable SB, 20 on definite SB and 4 were non-applicable. The review places emphasis on the recent evidence on prevalence, pathophysiology, diagnosis and management of SB in children and adolescents, with special focus on probable and definitive SB.

RESULTS

The prevalence ranges from 5% to 50% depending on the age range and on the SB diagnosis (possible, probable or definitive). The pathophysiology is multifactorial, arousal associated and with behavioural problems and sleep disorders (obstructive sleep apnoea, snoring, nightmares) as risk factors, as well as respiratory conditions (allergies, oral breathing). Screening should include questionnaires and dental assessment. Instrumental recording is helpful to confirm diagnosis although more studies are needed to validate this approach in children. SB management includes controlling orofacial and dental consequences and assessing for any other comorbidity. Management options include occlusal splints, oral appliances (advancement mandibular), rapid maxillary expansion and some medications, although this last option is supported by limited evidences in children.

CONCLUSION

Suggestions of future topics in research are delivered to better understand comorbidities, diagnosis and management with improved outcomes compared to what is currently available.

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

Background

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

Methods

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

Results

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

Discussion

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

Restless Legs Syndrome and Restless Sleep Disorder in Children

Restless legs syndrome (RLS) affects 2% of children presenting with symptoms of insomnia, restless sleep, decreased quality of life, and effects on cognition and behavior. The International RLS Study Group and the American Academy of Sleep Medicine have published guidelines for the diagnosis and treatment of RLS in children. Restless sleep disorder has been recently identified in children and presents with frequent movements during sleep and daytime symptoms with polysomnography findings of at least 5 large muscle movements at night. Treatment options for both disorders include iron supplementation, either oral or intravenous with improvement in nighttime and daytime symptoms.

Prevalence of Possible Sleep Bruxism and Its Association with Social and Orofacial Factors in Preschool Population

The prevalence of bruxism in the preschool population varies according to different investigations. The aim of this study was to investigate the prevalence of sleep bruxism and its relationship with social and orofacial factors in children aged 3 to 5 years. Three hundred forty-three preschool children were divided into two groups, one with nocturnal bruxism, as reported by parents, and another without this disorder. Questionnaires were distributed to the parents to determine the children's family social status and parafunctional habits at the time of the study. The clinical inspection confirmed the presence of certain parafunctional habits and the children's occlusal characteristics. The data obtained were analysed using descriptive statistics such as frequency chi-square tests to identify the influence of qualitative variables. Of the total sample, 28.9% of preschoolers presented sleep bruxism. The highest prevalence was observed in boys (61.6%) at the age of 5 years (41.4%). Characteristics associated with this pathology were lip incompetence, open bite, crossbite, and overbite, with p < 0.05. Sleep bruxism in preschool children has a higher prevalence in boys and is more frequently expressed from 5 years of age. Open bite, overbite, and crossbite should be considered factors associated with parafunction.

Sleep bruxism in children, from evidence to the clinic. A systematic review

Objectives

The present paper aims to systematically review the literature published from 2015 to 2023 on bruxism in children with the aim to compilate the best available evidence.

Materials and Methods

A systematic search in the National Library of Medicine's PubMed, Medline (EBSCO), SCOPUS, and Google Scholar databases was performed to identify all studies on humans assessing genetic, biopsychosocial, and sleep factors assessed with any different approach for sleep bruxism (SB) in children and its interventions. The selected articles were assessed independently by the two authors according to a structured reading of the article's format (PICO). The quality of the articles was evaluated using Quality Assessments Tool for Experimental Bruxism Studies (Qu-ATEBS) and the JBI critical appraisal tools.

Results

A total of 16 articles were included for discussion in the review and grouped into questionnaire/parental-report (n = 7), SB assessment through parental report of SB and clinical examination (n = 4), and instrumental assessment (n = 5) studies. The total quality scores evaluated with STROBE and Qu-ATEBS were high for all included papers. However, in general, there was no control of bias strategies and there was no control group in the intervention studies.

Conclusions

Investigations based on self-report, clinical, and instrumental bruxism assessment showed a positive association with genetics, quality of life aspects (school and emotional functions and overuse of screen-time), mother anxiety and family conformation, diet, alteration in sleep behaviors and architecture, and sleep breathing disorders. Additionally, the literature presents options to increase airway patency and, thus, reduce the occurrence of SB. Tooth wear was not found to be a major sign of SB in children. However, methods of SB assessment are heterogeneous and hamper a reliable comparison of the results.

Are lower urinary tract conditions more common in children with sleep bruxism?

INTRODUCTION

Sleep bruxism is a parasomnia caused by rhythmic and non-rhythmic activity of the masticatory muscles during sleep. Prevalence of sleep bruxism is reported up to 40.6% in the literature. Sleep bruxism is a multifactorial issue and associated with multiple dental complications, sleep-related disorders, and psychosocial problems. We aimed to investigate if children with sleep bruxism suffer more from lower urinary tract conditions.

MATERIALS AND METHODS

Prospectively 128 children were included in this study. Sixty-four children constituted in the bruxism group and 64 children constituted in the control group. Children who admitted to the pediatric dentistry clinic with bruxism symptoms were recruited in the bruxism group. Control group constituted of consecutive 64 children who admitted to the pediatric dentistry clinic for routine dental examination. Parents were asked to fill out a questionnaire including Dysfunctional Voiding and Incontinence Scoring System (DVISS) form. Children's demographic data, presence of urinary frequency, presence of urgency, behaviour of voiding postponement, presence of daytime urinary incontinence, presence of enuresis nocturna, presence of fecal incontinence, presence of constipation, status of circumcision, and presence of bruxism related symptoms were recorded. Children with a DVISS score above 8 were considered to have functional voiding disorder. All children underwent a dental examination.

RESULTS

The mean age of children was 73.3 ± 26.9 months. For all children (n = 128), the girl to boy ratio was 40:88. Mean DVISS score was 2.5 ± 3.8 and the mean QOL score was 0.1 ± 0.4 for all children. Eight (6.3%) children were found to have functional voiding disorder based on the DVISS score. There was no statistically significant difference for any lower urinary tract condition between the bruxism group and the control group (Table). Children with bruxism significantly had more tooth wear and masseter muscle hypertrophy (<0.001 and < 0.05).

DISCUSSION

Sleep bruxism has been linked to a number of health issues including dental, systemic and psychosocial problems. Tooth wears, fatigue/pain in chewing muscles, gum recession, facial pain, masseter muscle hypertrophy and temporomandibular joint damage are the main complications of bruxism. Moreover, bruxism has been associated with systemic diseases and sypmtoms like asthma, respiratory illnesses, enuresis nocturna, anxiety, and stress.

CONCLUSIONS

Children with sleep bruxism suffer more from tooth wear, masseter muscle hypertrophy, and regional pain over the jaw. Additionally morning fatigue, relationship issues, and respiratory illnesses are more common in bruxist children. Lower urinary tract conditions are not more frequent in children with sleep bruxism.

Relationship Analogy between Sleep Bruxism and Temporomandibular Disorders in Children: A Narrative Review

Sleep bruxism (SB) is a condition characterized by repetitive clenching or grinding teeth and/or by bracing or thrusting of the mandible during sleep. Although SB is not considered a disorder in children, SB can be a potential physical and psychological hazard or consequence, and this study examines whether SB is a risk factor for TMD as it is in adults. A narrative review on the topic of inferring the relationship between sleep bruxism and TMD in children was performed based on a search in the PubMed and Google Scholar databases for articles published between 1999 and 2022. A total of 76 articles were included in this review. SB is very common in children, may be related to psychological distress or sleep breathing disorder, with a prevalence of up to 49%, and mainly occurs in the non-rapid eye movement stage in the sleep structure. SB may be one cause of TMD. The prevalence of TMD in children is 16–33%. Compared to the female-dominant TMD prevalence in adults, the sex-differences in TMD prevalence in children are less pronounced. However, TMD-related pain is more prevalent in girls than in boys. Given the complex etiology of each of SB and TMD in children, it can be inferred that the explanation of the relationship between the two conditions is very challenging. Ultimately, their relationship should be understood in the individual biopsychosocial model in the process of special physical growth and mental development of children. Moreover, appropriate clinical guidelines for a definitive diagnosis of SB and TMD in children and more research with a high scientific evidence level, which is comprehensive, considering physical, psychological, genetic, and social cultural factors, are required.

Restless Sleep Disorder (RSD): a New Sleep Disorder in Children. A Rapid Review

PURPOSE OF REVIEW

Restless sleep disorder (RSD) is a recently identified pediatric sleep disorder characterized by frequent movements during sleep associated with daytime symptoms. In this review we summarize the expanding evidence of the clinical presentation of RSD, potential pathophysiology, associated comorbidities, and current treatment options that will help the pediatrician identify children with RSD in a timely manner.

RECENT FINDINGS

RSD is diagnosed in 7.7% of children referred evaluated in a pediatric sleep center. Children with RSD present with frequent nightly movements during sleep for at least 3 months, and have daytime symptoms related to poor sleep quality including excessive sleepiness, hyperactivity, irritability among other symptoms. Current evidence shows an increased sympathetic predominance, increased NREM sleep instability, and iron deficiency, as well as increased prevalence in parasomnias and attention deficit hyperactivity disorder. Consensus diagnostic criteria were recently published to diagnose RSD and emergent evidence suggests that iron supplementation improves its nighttime and daytime symptoms.

Sleep Bruxism in Children: Etiology, Diagnosis, and Treatment-A Literature Review

(1) Background: Bruxism, a condition characterized by grinding and involuntary clenching of the teeth, is a risk factor for the development of masticatory dysfunction. It can occur together with sleep disturbances and may be associated with abnormal body movements, breathing difficulties, increased muscle activity, and heart rate disturbances. This disorder is becoming an important dental concern in children. (2) Methods: A literature review was carried out based on a search in PubMed and Google Scholar databases for articles on bruxism in children, published between 2014 and 2021. The etiology, diagnosis, and treatment of bruxism in children were of particular interest in the study. (3) Results: A total of 40 articles were included in the review. The analyzed studies indicated that the prevalence rates of bruxism in children vary widely from 13% to 49%. The etiology of bruxism is complex and incomprehensible, and the main diagnostic criteria for this condition in children are subjective observation, clinical history, and clinical examination. The recommended therapy for sleep bruxism in children is physiotherapy and psychotherapy. (4) Conclusions: Dentists and primary care physicians should correctly diagnose bruxism in children, educate parents, prevent potential consequences for oral health, and identify possible comorbidities. Appropriate clinical guidelines for the treatment and prophylaxis of bruxism in children should also be developed.

A world panorama of bruxism in children and adolescents with emphasis on associated sleep features: A bibliometric analysis

BACKGROUND AND OBJECTIVES

To present a world panorama of the published papers on bruxism in children and adolescents, emphasising the characteristics of studies related to the sleep features of these patients.

METHODS

Literature searches were conducted in six databases without language or date restrictions. Data on the titles, types of study, main subjects, countries of origin, keywords, years of publication, authors and their network collaborations, journals and sleep studies were extracted and analysed using VantagePoint™ software.

RESULTS

A total of 725 studies met the eligibility criteria. Most included only children (75.31%), with observational design (66.34%), and risk or aetiology (53.93%) as the main subject. Brazil (18.06%) and Brazilian authors (54.84%) had the largest number of studies, with a low amount of network collaboration. The Journal of Oral Rehabilitation published most of the studies (6.2%); publications in this field have grown considerably from 2000 to 2020. Of the studies, 123 (16.96%) included sleep studies; night sweating, restless sleep, sleep talking, mouth breathing, snoring, obstructive sleep apnoea syndrome, sleep-disordered breathing, nightmares, poor sleep quality and duration, and daytime naps were significantly associated with bruxism in most.

CONCLUSION

Studies on bruxism in children and adolescents have increased in the past 20 years, with most being observational, and risk or aetiology as the main subject. Brazil and the Journal of Oral Rehabilitation have published most in the field. Sleep studies have shown some features associated with bruxism, such as night sweating, restless sleep, somniloquy, snoring, breathing problems, nightmares, daytime naps, and poor sleep quality and duration.

Relationships between cortical, cardiac, and arousal-motor activities in the genesis of rhythmic masticatory muscle activity across sleep cycles in primary sleep bruxism children

STUDY OBJECTIVES

The present study aimed to clarify the physiological relationships between rhythmic masticatory muscle activity (RMMA) and cyclic changes in cortical, autonomic, and arousal-motor activities during sleep in sleep bruxism (SB) children.

METHODS

Polysomnographic recordings were performed on fifteen SB children (9 boys, 6 girls, 10.3 ± 2.5 years) and eighteen control children (5 boys, 13 girls, 10.7 ± 3.1 years) free from sleep and developmental disorders. Sleep and RMMA were scored by the standard rules. Sleep cycle was divided into NREM and REM sleep segments and the frequency of RMMA, transient arousal and movement, and cortical and cardiac activities were then quantitatively analyzed in relation to sleep cycles.

RESULTS

Neither sleep architecture nor sleep stage distribution of RMMA significantly differed between two groups. In sleep cycles, SB children showed more frequent RMMA in all segments than controls, while cyclic changes in cortical and autonomic activities did not significantly differ between two groups. In SB children, RMMA was the most frequent in the last NREM segment before REM sleep and was associated with increases in cortical beta activity and arousal; more than 70% of RMMA time-dependently occurred with cortical and motor arousals.

CONCLUSIONS

This is the first study to suggest that the potentiation of RMMA occurrence was associated with transient arousal under cyclic sleep processes in primary SB children.

Sleep spindle density is associated with worry in children with generalized anxiety disorder and healthy controls

BACKGROUND

Childhood generalized anxiety disorder (GAD), characterized by uncontrollable worry, is associated with long-term psychopathology risk, yet understanding of developmental trajectories is limited. Despite common complaints about sleep, 'macro' sleep abnormalities have not been identified. Emerging findings suggest micro-architectural features of sleep, including sleep spindles, differentiate various psychiatric populations. The current study investigated sleep spindle density during non-rapid eye movement (NREM) sleep among youth with GAD and healthy controls, including relationships with anxiety, worry, global functioning, and subjective sleep quality.

METHODS

58 pre-pubertal children, n = 26 with GAD and n = 32 matched healthy controls, aged 7-11 years (M = 8.86, SD=1.47), completed diagnostic assessments and a week of actigraphy monitoring prior to a night of polysomnography (PSG) either at home or in a sleep laboratory. NREM spindle activity was detected in frontal and central regions.

RESULTS

Sleep spindle activity did not differ based on diagnostic group or sex. Sleep spindles were unassociated with anxiety and sleep quality but showed a significant positive association with worry in all youth. Among youth with GAD, global functioning was negatively associated with spindle density in frontal regions during NREM stage 3. Spindle density was significantly greater during in-lab compared to at-home PSG.

LIMITATIONS

The small sample size and reliance on only one night of PSG necessitate additional studies.

CONCLUSIONS

The identified link between spindle activity and worry in pre-pubertal children highlights a need for investigations on transdiagnostic features of child psychopathology rather than specific disorders. Longitudinal studies are needed to explore spindle characteristics and affective risk across development.

Pediatric pulmonology year in review 2018: Sleep medicine

Pediatric Pulmonology publishes original research, case reports, and review articles on topics related to a wide range of children's respiratory disorders. In this article (Part 4 of a five-part series), we summarize the past year's publications in sleep medicine, in the context of selected literature in this area from other journals. Articles are highlighted on topics including infant sleep, diagnosis, and treatment of obstructive sleep apnea, and sleep disorders in chronic disease.