Psychiatric comorbidity in children and adolescents with restless legs syndrome: a retrospective study

Classification and Epidemiology of Sleep Disorders in Children and Adolescents

Sleep disturbances are common in children and adolescents but still remain unrecognized and undertreated. Several classification systems of sleep disorders are available, which include recent attempts to develop more specific nosologic categories that reflect developmental aspects of sleep. The prevalence of sleep disorders has been studied across various samples of healthy, typically developing children and those with special medical, psychiatric, and neurodevelopmental needs. Sleep disorders are highly prevalent in children and adolescents with psychiatric disorders, making it important for mental health professionals to be aware of sleep problems and to address them in the context of psychiatric comorbidities.

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

Pediatric sleep: current knowledge, gaps, and opportunities for the future

This White Paper addresses the current gaps in knowledge, as well as opportunities for future studies in pediatric sleep. The Sleep Research Society's Pipeline Development Committee assembled a panel of experts tasked to provide information to those interested in learning more about the field of pediatric sleep, including trainees. We cover the scope of pediatric sleep, including epidemiological studies and the development of sleep and circadian rhythms in early childhood and adolescence. Additionally, we discuss current knowledge of insufficient sleep and circadian disruption, addressing the neuropsychological impact (affective functioning) and cardiometabolic consequences. A significant portion of this White Paper explores pediatric sleep disorders (including circadian rhythm disorders, insomnia, restless leg and periodic limb movement disorder, narcolepsy, and sleep apnea), as well as sleep and neurodevelopment disorders (e.g. autism and attention deficit hyperactivity disorder). Finally, we end with a discussion on sleep and public health policy. Although we have made strides in our knowledge of pediatric sleep, it is imperative that we address the gaps to the best of our knowledge and the pitfalls of our methodologies. For example, more work needs to be done to assess pediatric sleep using objective methodologies (i.e. actigraphy and polysomnography), to explore sleep disparities, to improve accessibility to evidence-based treatments, and to identify potential risks and protective markers of disorders in children. Expanding trainee exposure to pediatric sleep and elucidating future directions for study will significantly improve the future of the field.

Sleep-related challenges and family functioning in children and adolescents previously treated for craniopharyngioma

PURPOSE

We investigated sleep-related challenges and their association with family functioning in children and adolescents previously treated for craniopharyngioma.

DESIGN

Quantitative approach using psychometrically validated measures.

SAMPLE

Thirty-nine children and adolescents who had been treated for craniopharyngioma and their primary caregivers.

METHODS

Caregivers and youth completed measures of family functioning, family routines, daytime sleepiness, and children's sleep patterns.

FINDINGS

Children and adolescents with craniopharyngioma had significantly higher ratings of self-reported excessive daytime sleepiness, bedtime fears/worries, and restless legs symptoms compared to their relatively healthy peers. Lack of family routines and poor family functioning were related to poor sleep-related outcomes and increased excessive daytime sleepiness.

IMPLICATIONS FOR PSYCHOSOCIAL PROVIDERS

Providers should consider assessing sleep difficulties in pediatric brain tumor survivors from a family systems perspective. Intervening on family-related factors may help improve sleep and other health-related outcomes, whereas intervening on sleep may help improve family functioning.

Attention deficit hyperactivity disorder and restless leg syndrome across the lifespan: A systematic review and meta-analysis

This systematic review aims to assess the association between attention deficit hyperactivity disorder (ADHD) and restless legs syndrome (RLS) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases were searched for original articles that reported prevalence data on ADHD and RLS until January 24th, 2023. Two independent reviewers evaluated the quality of the articles using the National Institutes of Health assessment tool. Among the 208 articles identified between 1996 and 2022, 29 were included. In large general population studies, 2.6-15.3% of participants met the RLS criteria, of which 3.2-17.4% presented with ADHD. In the ADHD group, RLS symptoms ranged from 11 to 42.9% in children and 20-33.0% in adults. This suggests a strong co-occurrence between RLS and ADHD. A common characteristic of these conditions is sleep fragmentation, as discussed in the reviewed papers. Although large-scale studies with comparable diagnostic criteria across the lifespan are required, our findings may advocate a possible common physiological pathway, including sleep fragmentation and dopaminergic system impairment.

Restless sleep disorder, restless legs syndrome, and periodic limb movement disorder-Sleep in motion!

Sleep-related movement disorders (SRMDs) represent an important part of pediatric sleep disorders. The most common complaint in SRMD is restless sleep at night. Restless sleep is reported in up to 80% of children with restless legs syndrome (RLS) and children with periodic limb movements of sleep (PLMS) disorder (PLMD). However, restless sleep causing daytime behavioral consequences can be seen in children without another apparent condition and has recently been identified as a new independent primary pediatric sleep disorder, called restless sleep disorder (RSD). This study describes these three main SRMDs (RSD, RLS, and PLMD), explains the new consensus criteria for RSD, emphasizes the rapidly evolving areas of research in this field, and proposes recommendations for future research. In particular, the published data constitute convincing evidence that sleep-related movements are disruptors of sleep quality and continuity. However, while important advancements have recently been reported in adults, a detailed analysis of the phenomenology and consequences of sleep-related movements has just started in children. New approaches, standardized diagnostic methods, and specific guidelines are needed in the field of pediatric SRMD.

Restless Legs Syndrome Prevalence and Clinical Correlates Among Psychiatric Inpatients: A Multicenter Study

Background

There are only limited reports on the prevalence of restless legs syndrome (RLS) in patients with psychiatric disorders. The present study aimed to evaluate the prevalence and clinical correlates in psychiatric inpatients in Germany and Switzerland.

Methods

This is a multicenter cross-sectional study of psychiatric inpatients with an age above 18 years that were diagnosed and evaluated face-to-face using the International RLS Study Group criteria (IRLSSG) and the International RLS severity scale (IRLS). In addition to sociodemographic and biometric data, sleep quality and mood were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Epworth Sleepiness Scale (ESS), and the Patient Health Questionnaire (PHQ-9). In addition to univariate statistics used to describe and statistically analyze differences in variables of interest between patients with and without RLS, a logistic model was employed to identify predictors for the occurrence of RLS.

Results

The prevalence of RLS in a sample of 317 psychiatric inpatients was 16.4%, and 76.9% of these were diagnosed with RLS for the first time. RLS severity was moderate to severe (IRLS ± SD: 20.3 ± 8.4). The prevalences in women (p = 0.0036) and in first-degree relatives with RLS (p = 0.0108) as well as the body mass index (BMI, p = 0.0161) were significantly higher among patients with RLS, while alcohol consumption was significantly lower in the RLS group. With the exception of atypical antipsychotics, treatment with psychotropic drugs was not associated with RLS symptoms. Regarding subjective sleep quality and mood, scores of the PSQI (p = 0.0007), ISI (p = 0.0003), and ESS (p = 0.0005) were higher in patients with RLS, while PHQ-9 scores were not different. A logistic regression analysis identified gender (OR 2.67; 95% CI [1.25; 5.72]), first-degree relatives with RLS (OR 3.29; 95% CI [1.11; 9.73], ESS score (OR 1.09; 95% CI [1.01; 1.17]), and rare alcohol consumption (OR 0.45; 95% CI [0.22; 0.94] as predictors for RLS.

Conclusions

Clinically significant RLS had a high prevalence in psychiatric patients. RLS was associated with higher BMI, impaired sleep quality, and lower alcohol consumption. A systematic assessment of restless legs symptoms might contribute to improve the treatment of psychiatric patients.

Non-mental diseases associated with ADHD across the lifespan: Fidgety Philipp and Pippi Longstocking at risk of multimorbidity?

Several non-mental diseases seem to be associated with an increased risk of ADHD and ADHD seems to be associated with increased risk for non-mental diseases. The underlying trajectories leading to such brain-body co-occurrences are often unclear - are there direct causal relationships from one disorder to the other, or does the sharing of genetic and/or environmental risk factors lead to their occurring together more frequently or both? Our goal with this narrative review was to provide a conceptual synthesis of the associations between ADHD and non-mental disease across the lifespan. We discuss potential shared pathologic mechanisms, genetic background and treatments in co-occurring diseases. For those co-occurrences for which published studies with sufficient sample sizes exist, meta-analyses have been published by others and we discuss those in detail. We conclude that non-mental diseases are common in ADHD and vice versa and add to the disease burden of the patient across the lifespan. Insufficient attention to such co-occurring conditions may result in missed diagnoses and suboptimal treatment in the affected individuals.

Mental health and sleep habits/problems in children aged 3-4 years: a population study

Background

Sleep is essential for mental health at all ages, but few studies have investigated the importance of sleep for mental health in early childhood. Therefore, this study examined the association between mental health and sleep habits/problems in children aged 34 years.

Methods

Children aged 3 to 4 years who were living in the community (n=415; 211/204 boys/girls) were recruited for this study. Their mental health was assessed using the Strengths and Difficulties Questionnaire (SDQ), and their sleep habits/problems were evaluated using the Child and Adolescent Sleep Checklist.

Results

Based on the total difficulties score of the SDQ, the children were divided into two groups: a poor mental health group (n=76) and a control group (n=339). In terms of sleep habits, which included total sleep time, bedtime, wake time, and nap conditions, there were no differences between the two groups. Regarding sleep-related problems, however, anxiety before going to sleep (p=0.026), circadian rhythm abnormalities (p=0.014), and sleepiness during classes outside of naptimes (p=0.031) were significantly higher in the poor mental health group than in the control group. Multiple regression analysis showed that poor mental health status was significantly associated with sleepiness and snoring (p=0.017 and p=0.018, respectively).

Conclusions

The mental health status of 34-year-old children was associated with sleep-related problems, namely sleepiness and snoring. Healthcare providers should pay attention to childrens irregular sleep-wake patterns; moreover, interventions for appropriate sleep hygiene will reduce the psychological burden on both children and their families.

Pediatric Restless Legs Syndrome

Early-onset restless legs syndrome has a relatively high prevalence in pediatrics, is highly familial, and is often preceded by a diagnosis of periodic limb movement disorder or childhood insomnia. Diagnostic criteria are derived but not equal to those of the adult syndrome and are adapted according to children's age and linguistic competence. Diagnosis requires parents or caregivers to participate; video-polysomnographic nocturnal recording, although not mandatory, may help confirm dubious cases. The syndrome severely impacts children's sleep and cognitive-behavioral abilities. Iron supplementation is currently the most used and viable therapeutic option.

Classification and Epidemiology of Sleep Disorders in Children and Adolescents

Sleep disturbances are common in children and adolescents but still remain unrecognized and undertreated. Several classification systems of sleep disorders are available, which include recent attempts to develop more specific nosologic categories that reflect developmental aspects of sleep. The prevalence of sleep disorders has been studied across various samples of healthy, typically developing children and those with special medical, psychiatric, and neurodevelopmental needs. Sleep disorders are highly prevalent in children and adolescents with psychiatric disorders, making it important for mental health professionals to be aware of sleep problems and to address them in the context of psychiatric comorbidities.

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

Sleep-Wake Disorders in Childhood

PURPOSE OF REVIEW

The presentation of sleep issues in childhood differs from the presentation in adulthood and may be more subtle. Sleep issues may affect children differently than adults, and distinct treatment approaches are often used in children.

RECENT FINDINGS

Sodium oxybate was approved by the US Food and Drug Administration (FDA) in October 2018 for an expanded indication of treatment of sleepiness or cataplexy in patients with narcolepsy type 1 or narcolepsy type 2 aged 7 years or older, with side effect and safety profiles similar to those seen in adults. Restless sleep disorder is a recently proposed entity in which restless sleep, daytime sleepiness, and often iron deficiency are observed, but children do not meet the criteria for restless legs syndrome or periodic limb movement disorder.

SUMMARY

Children's sleep is discussed in this article, including normal sleep patterns and effects of insufficient sleep. Sleep disorders of childhood are reviewed, including insomnia, obstructive sleep apnea, restless legs syndrome, parasomnias, narcolepsy, and Kleine-Levin syndrome. Children with neurologic issues or neurodevelopmental disorders frequently have sleep disorders arising from an interaction of heterogeneous factors. Further attention to sleep may often be warranted through a polysomnogram or referral to a pediatric sleep specialist. Sleep disorders may cause indelible effects on children's cognitive functioning, general health, and well-being, and awareness of sleep disorders is imperative for neurologists who treat children.

Restless legs syndrome in children with allergic rhinitis: A comparative study on frequency, severity and sleep quality

Objectives

This study aims to investigate the frequency and severity of restless legs syndrome (RLS) and its relationship with sleep quality in children with allergic rhinitis (AR) with the hypothesis that comorbid RLS may be an additional causative factor of sleep disturbances in pediatric AR.

Patients and methods

A total of 143 children with AR (aged 8-18 years) and 144 healthy control subjects (aged 8-18 years) were included. The diagnosis of AR was established on history, clinical examination and skin prick test according to the Allergic Rhinitis and its Impact on Asthma guidelines. Presence of RLS was determined using the International RLS study group (IRLSSG) criteria. The severity of RLS was assessed using the IRLSSG rating scale. Sleep quality was evaluated by Pittsburgh Sleep Quality Index (PSQI).

Results

Thirteen patients (9.1%) in AR group, and six children (4.2%) in control group had RLS (p=0.159). The frequency of RLS in AR group was higher than two folds when compared to the control group; however, the difference was not statistically significant. Restless legs syndrome severity score was significantly higher in AR group than control group (15.00 [11-20] and 11.00 [10-16] respectively, p=0.046). Total PSQI scores were similar between groups. Also, no significant differences were observed in total PSQI scores of AR patients with or without RLS.

Conclusion

Restless legs syndrome was not more common but was more severe in children with AR. There was no evidence that RLS has an obvious effect on sleep quality in children with AR.

Prevalence and Clinical Characteristics of the Restless Legs Syndrome (RLS) in Patients Diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD) in Antioquia

Introduction:

Attention Deficit Hyperactivity Disorder (ADHD) is the most common behavioral issue for children. One of the sleeping disorders most frequently related to ADHD is the Restless Legs Syndrome (RLS), characterized by an irresistible urge to move the legs, something that is generally associated with paresthesias and motor restlessness. The prevalence rate of RLS in children diagnosed with ADHD is close to 18%, but in Colombia, these cases have been hardly studied.

Objective:

To determine the frequency of RLS, in children with ADHD.

Methods:

A cross-sectional study, filled out by parents of children diagnosed with ADHD, were analyzed. This questionnaire contained clinical criteria for classifying ADHD according to the DSM-IV, as well as diagnostic criteria for RLS by the National Institutes of Health (2003).

Results:

A predominance rate of 65.6% in combined ADHD was observed in children with RLS criteria. Upon carrying out an exploratory data analysis, it was found that having a family history of RLS and belonging to the middle or low socioeconomic strata are conditions associated with the presence of RLS in children with ADHD, with a significant p (p < 0.000) and a PR of 4.47 (3.16-6.32).

Conclusions:

The prevalence of RLS was similar to the findings of other clinical investigations. However, it highlights new prevalence values in relation to the comorbidity between ADHD and RLS, suggesting the need for new clinical and therapeutic alternatives amidst the presence of both syndromes.

Evidence-based and consensus clinical practice guidelines for the iron treatment of restless legs syndrome/Willis-Ekbom disease in adults and children: an IRLSSG task force report

BACKGROUND

Brain iron deficiency has been implicated in the pathophysiology of RLS, and current RLS treatment guidelines recommend iron treatment when peripheral iron levels are low. In order to assess the evidence on the oral and intravenous (IV) iron treatment of RLS and periodic limb movement disorder (PLMD) in adults and children, the International Restless Legs Syndrome Study Group (IRLSSG) formed a task force to review these studies and provide evidence-based and consensus guidelines for the iron treatment of RLS in adults, and RLS and PLMD in children.

METHODS

A literature search was performed to identify papers appearing in MEDLINE from its inception to July 2016. The following inclusion criteria were used: human research on the treatment of RLS or periodic limb movements (PLM) with iron, sample size of at least five, and published in English. Two task force members independently evaluated each paper and classified the quality of evidence provided.

RESULTS

A total of 299 papers were identified, of these 31 papers met the inclusion criteria. Four studies in adults were given a Class I rating (one for IV iron sucrose, and three for IV ferric carboxymaltose); only Class IV studies have evaluated iron treatment in children. Ferric carboxymaltose (1000 mg) is effective for treating moderate to severe RLS in those with serum ferritin <300 μg/l and could be used as first-line treatment for RLS in adults. Oral iron (65 mg elemental iron) is possibly effective for treating RLS in those with serum ferritin ≤75 μg/l. There is insufficient evidence to make conclusions on the efficacy of oral iron or IV iron in children.

CONCLUSIONS

Consensus recommendations based on clinical practice are presented, including when to use oral iron or IV iron, and recommendations on repeated iron treatments. New iron treatment algorithms, based on evidence and consensus opinion have been developed.

Sleep Disorders: Assessment and Treatment in Preschool-Aged Children

Sleep issues are common in preschoolers, defined in this article as ages 3 to 5 years. Sleep deprivation can cause behavioral and cognitive issues. Sleep issues seen in the preschool years include insomnia, obstructive sleep apnea, parasomnias, and restless legs syndrome. Sleep issues seem to exacerbate mood and attention disturbances. Conversely, children with psychiatric disorders are likely to have sleep problems. Treatment of sleep issues is important for long-term mental health and optimization of functioning.

Restless Legs Syndrome: From Pathophysiology to Clinical Diagnosis and Management

Restless legs syndrome (RLS), a common neurological sensorimotor disorder in western countries, has gained more and more attention in Asian countries. The prevalence of RLS is higher in older people and females. RLS is most commonly related to iron deficiency, pregnancy and uremia. The RLS symptoms show a significant circadian rhythm and a close relationship to periodic limb movements (PLMs) in clinical observations, while the pathophysiological pathways are still unknown. The diagnostic criteria have been revised in 2012 to improve the validity of RLS diagnosis. Recent studies have suggested an important role of iron decrease of brain in RLS pathophysiology. Dopaminergic (DA) system dysfunction in A11 cell groups has been recognized long ago from clinical treatment and autopsy. Nowadays, it is believed that iron dysfunction can affect DA system from different pathways and opioids have a protective effect on DA system. Several susceptible single nucleotide polymorphisms such as BTBD9 and MEIS1, which are thought to be involved in embryonic neuronal development, have been reported to be associated with RLS. Several pharmacological and non-pharmacological treatment are discussed in this review. First-line treatments of RLS include DA agents and α2δ agonists. Augmentation is very common in long-term treatment of RLS which makes prevention and management of augmentation very important for RLS patients. A combination of different types of medication is effective in preventing and treating augmentation. The knowledge on RLS is still limited, the pathophysiology and better management of RLS remain to be discovered.

"Emplotted Narratives" and Structured "Behavioral Observations" Supporting the Diagnosis of Willis-Ekbom Disease/Restless Legs Syndrome in Children with Neurodevelopmental Conditions

Background

Willis‐Ekbom disease/restless legs syndrome (WED/RLS) seems to be a frequent cause of intractable chronic insomnia (ICI) but is under‐recognized in children/adolescents with neurodevelopmental conditions (NDCs), as many patients do not have the ability to express the underlying “urge‐to‐move”. In light of this, we aim to develop a protocol for behavioral observations supporting the diagnosis of WED/RLS.

Methods

We investigated 26 pediatric patients (age 1–16 years, median 8) with NDCs, ICI and evidence of familial WED/RLS employing (1) “emplotted narratives” for description of the various “urge‐to‐move” presentations and (2) self‐description and “behavioral observations” during a “suggested clinical immobilization test” (SCIT).

Results

Parental narratives reflected typical WED/RLS‐related “urge‐to‐move” symptoms during day‐, bed‐, and nighttime in all patients. Fifteen out of 26 patients could describe the “urge‐to‐move” during the SCIT. Ten out of 26 patients, unable to describe their symptoms due to cognitive disabilities, showed patterns of “relieving‐movements” upon observation. Sensory processing abnormalities were reported in all patients, with tactile sensitivities (26/26) (including shifted pain threshold) as the most common sensory domain.

Conclusion

“Emplotted narratives” and structured “behavioral observations” support recognition of familial WED/RLS associated movement patterns and provide a useful tool for the diagnosis of WED/RLS in children with NDCs in a clinical office setting.

Musculoskeletal pain is associated with restless legs syndrome in young adults

BACKGROUND

In recent years, there is considerable evidence of a relationship between the sensorimotor disorder restless legs syndrome (RLS) and pain disorders, including migraine and fibromyalgia. An association between multi-site pain and RLS has been reported in adult women. In the current study, we explored the association between musculoskeletal (MSK) pain and RLS in a large cohort of young adults.

METHODS

Twenty two year olds (n = 1072), followed since birth of part of the Western Australian Pregnancy Cohort (Raine) Study, provided data on MSK pain (duration, severity, frequency, number of pain sites). RLS was considered present when 4 diagnostic criteria recommended by the International Restless Legs Syndrome Study Group were met (urge to move, dysaesthesia, relief by movement, worsening symptoms during the evening/night) and participants had these symptoms at least 5 times per month. Associations between MSK pain and RLS were analyzed by multivariable logistic regression with bias-corrected bootstrapped confidence intervals, with final models adjusted for sex, psychological distress and sleep quality.

RESULTS

The prevalence of RLS was 3.0 % and MSK pain was reported by 37.4 % of the participants. In multivariable logistic regression models, strong associations were found between RLS-diagnosis and long duration (three months or more) of MSK pain (odds ratio 3.6, 95 % confidence interval 1.4-9.2) and reporting three or more pain sites (4.9, 1.6-14.6).

CONCLUSIONS

Different dimensions of MSK pain were associated with RLS in young adults, suggestive of shared pathophysiological mechanisms. Overlap between these conditions requires more clinical and research attention.

Brazilian consensus on guidelines for diagnosis and treatment for restless legs syndrome

The Consensus on restless legs syndrome is an effort of neurologists from several Brazilian states, which tirelessly reviewed the literature of recent years in search of evidence, both in regard to diagnosis and treatment, according to the Oxford Centre for Evidence-based Medicine.

Diagnosis, comorbidities, and management of restless legs syndrome

OBJECTIVE

This narrative review describes the differential diagnosis of restless legs syndrome, and provides an overview of the evidence for the associations between RLS and potential comorbidities. Secondary causes of RLS and the characteristics of pediatric RLS are also discussed. Finally, management strategies for RLS are summarized.

METHODS

The review began with a comprehensive PubMed search for 'restless legs syndrome/Willis-Ekbom disease' in combination with the following: anxiety, arthritis, attention-deficit hyperactivity disorder, cardiac, cardiovascular disease, comorbidities, depression, end-stage renal disease, erectile dysfunction, fibromyalgia, insomnia, kidney disease, liver disease, migraine, mood disorder, multiple sclerosis, narcolepsy, neuropathy, obesity, pain, Parkinson's disease, polyneuropathy, pregnancy, psychiatric disorder, sleep disorder, somatoform pain disorder, and uremia. Additional papers were identified by reviewing the reference lists of retrieved publications.

RESULTS AND CONCLUSIONS

Although clinical diagnosis of RLS can be straightforward, diagnostic challenges may arise when patients present with comorbid conditions. Comorbidities of RLS include insomnia, depressive and anxiety disorders, and pain disorders. Differential diagnosis is particularly important, as some of the medications used to treat insomnia and depression may exacerbate RLS symptoms. Appropriate diagnosis and management of RLS symptoms may benefit patient well-being and, in some cases, may lessen comorbid disease burden. Therefore, it is important that physicians are aware of the presence of RLS when treating patients with conditions that commonly co-occur with the disorder.

Restless legs syndrome, sleep, and quality of life among adolescents and young adults

OBJECTIVE

Clinical reports in children implicate restless legs syndrome (RLS) with sleep and behavior problems. However, population-based studies on this association in adolescents and young adults are limited. Furthermore, few studies have evaluated the association between symptoms consistent with RLS and quality of life (QoL).

STUDY DESIGN

This cross-sectional study included 214 Caucasian and Hispanic adolescents and young adults aged 12-20 years. Symptoms consistent with RLS were based on four essential criteria and if the symptoms occurred ≥ 5 days/ month. Trouble falling asleep was present if reported "yes, still have the problem." Quality of life (QoL) was assessed using the Pediatric QoL Inventory. Three summary QoL scores ranging from 0-100 were evaluated; higher scores indicated better QoL.

RESULTS

Participants were 50% male and 68.1% Caucasian. Prevalence of RLS was 8.4% (n = 18). RLS was associated with trouble falling asleep (OR = 3.1, p = 0.049), and trouble falling asleep was associated with worse Psychosocial Health scores (Coeff. -5.6, p = 0.004) and Total Scale scores for quality of life (Coeff. -4.6, p = 0.007).

CONCLUSIONS

The prevalence of symptoms consistent with RLS in this community-based sample of adolescents and young adults, aged 12-20, is comparable to rates reported in older cohorts. Symptoms consistent with RLS may be associated with trouble falling asleep and psychosocial distress that may contribute to a lower health-related quality of life.

Associations of child insomnia, sleep movement, and their persistence with mental health symptoms in childhood and adolescence

STUDY OBJECTIVES

To examine the patterns of insomnia and sleep-related movement from ages 4.5 to 9 years, their concurrent associations with mental health symptoms in childhood, and the longitudinal associations of sleep-problem persistence with mental health symptoms at ages 9 and 18 years.

DESIGN

A 14-year prospective follow-up study. Assessments included maternal report on the Children's Sleep Habits Questionnaire at ages 4.5 and 9, and child mental health symptoms via maternal report at age 4.5, multi-informant (child, teacher, mother) report at age 9, and adolescent report at age 18.

SETTING

Community.

PARTICIPANTS

A total of 396 children (51% female).

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Sleep problems were more common at age 4.5 than 9; symptoms of insomnia and abnormal sleep movement both had persistence rates of 9-10%. At age 4.5, insomnia was associated with hostile-aggressive and hyperactive-distractible behavior, but there were no significant associations for sleep movement. At age 9, both insomnia and sleep movement were associated with symptoms of depression, externalizing, and attention deficit hyperactivity disorder (ADHD). Insomnia persistence was associated with symptoms of depression, externalizing, and ADHD at age 9 and anxiety and externalizing at age 18; sleep- movement persistence was associated with externalizing and ADHD at age 9, and ADHD at age 18. The age 18 persistence effects for insomnia and anxiety and for sleep movement and ADHD were significant when controlling for earlier mental health.

CONCLUSIONS

Childhood insomnia and sleep movement are common and associated with mental health symptoms. Their persistence from middle to late childhood predicts associations with specific types of mental health symptoms at age 18.

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.

Sleep in children with autism spectrum disorder

Children with autism spectrum disorder demonstrate an increased prevalence of difficulties with sleep initiation and maintenance. The consequences may include alterations in daytime behavior, memory, and learning in patients, and significant stress in caretakers. The dysregulation of melatonin synthesis, sensitization to environmental stimuli, behavioral insomnia syndromes, delayed sleep phase syndrome, rapid eye movement sleep behavior disorder, and comorbid anxiety, depression, and epilepsy comprise common etiologic factors. The clinical assessment of sleep problems in this population and a management algorithm are presented.

Motor restlessness, sleep disturbances, thermal sensory alterations and elevated serum iron levels in Btbd9 mutant mice

Restless legs syndrome (RLS), also known as Willis-Ekbom disease, is a sensory-motor neurological disorder with a circadian component. RLS is characterized by uncomfortable sensations in the extremities, generally at night or during sleep, which often leads to an uncontrollable urge to move them for relief. Recently, genomic studies identified single-nucleotide polymorphisms in BTBD9, along with three other genes, as being associated with a higher risk of RLS. Little is known about the function of BTBD9 or its potential role in the pathophysiology of RLS. We therefore examined a line of Btbd9 mutant mice we recently generated for phenotypes similar to symptoms found in RLS patients. We observed that the Btbd9 mutant mice had motor restlessness, sensory alterations likely limited to the rest phase, and decreased sleep and increased wake times during the rest phase. Additionally, the Btbd9 mutant mice had altered serum iron levels and monoamine neurotransmitter systems. Furthermore, the sensory alterations in the Btbd9 mutant mice were relieved using ropinirole, a dopaminergic agonist widely used for RLS treatment. These results, taken together, suggest that the Btbd9 mutant mice model several characteristics similar to RLS and would therefore be the first genotypic mouse model of RLS. Furthermore, our data provide further evidence that BTBD9 is involved in RLS, and future studies of the Btbd9 mutant mice will help shine light on its role in the pathophysiology of RLS. Finally, our data argue for the utility of Btbd9 mutant mice to discover and screen novel therapeutics for RLS.