Sleep disorders in Tourette syndrome: a primary or unrelated problem?

Bedtime Regularity and Sleep Sufficiency in Children With Tourette Syndrome

BACKGROUND

Despite research demonstrating sleep disturbance in children with Tourette syndrome (TS), few studies have examined bedtime regularity and sleep sufficiency, two important sleep health dimensions. Therefore, this study examined bedtime regularity and sleep sufficiency in children with TS relative to matched healthy control subjects, and its associated demographic, clinical, and behavioral factors.

METHODS

Participants were 384 parents or caregivers of children aged three to 17 years, including 192 with current TS and 192 matched healthy control subjects drawn from the 2020-2021 cycle of the National Survey of Children's Health. Parents completed questions assessing demographic (i.e., age, race, sex), clinical (i.e., attention-deficit/hyperactivity disorder [ADHD], autism spectrum disorder, anxiety, depression, tic severity, behavioral or conduct problems, ADHD medication, health condition-related impairment), and behavioral (i.e., screen time) characteristics. Mann-Whitney U test and chi-square test of independence were performed to compare groups on bedtime regularity and sleep sufficiency, respectively. Ordinal regression and binary logistic regression without and with backward elimination were performed to evaluate indicators of bedtime regularity and sleep sufficiency, respectively, in children with TS.

RESULTS

Children with current TS had significantly poorer bedtime regularity, but not sleep sufficiency, relative to matched healthy control subjects. In children with TS, anxiety and two or more hours of daily screen time were associated with higher likelihood of poor bedtime regularity. Autism was associated with lower likelihood of insufficient sleep, and depression was associated with increased likelihood of insufficient sleep.

CONCLUSIONS

Findings put forth screen time, anxiety, and depression as intervention targets to optimize sleep health in children with TS.

Prevalence and influencing factors of sleep problems in tic disorders: a meta-analysis

BACKGROUND

Sleep problems are commonly observed in patients with tic disorders. Nevertheless, studies have demonstrated a wide variation in the prevalence of sleep disturbances among this population. Consequently, it remains ambiguous whether sleep issues are inherently characteristic of tic disorders or are influenced by external factors.

METHODS

We conducted a comprehensive search across various databases and performed a meta-analysis to determine the prevalence of sleep problems in tic disorders. Additionally, we assessed pre-existing comorbidities and associated characteristics using meta-regression analysis.

RESULTS

After including 33 studies in the final meta-analysis, we found that the pooled prevalence of sleep problems in tic disorders was 34% (95%CI: 26% to 43%). Meta-regression analysis revealed that the presence of co-occurring symptoms of ADHD (p < 0.05), obsession compulsive disorder/behaviours (p < 0.05), anxiety (p < 0.001), and mood disorders (p < 0.001) was associated with an increased likelihood of experiencing sleep problems.

CONCLUSIONS

Our findings consistently indicate that individuals with tic disorders frequently encounter significant sleep problems. This underscores the importance of routinely screening for sleep problems during clinical assessments. Effectively managing sleep problems in patients with tic disorders is crucial not only for the well-being of the patients themselves but also for their families.

Clinical Characteristics of Children With Tourette Syndrome With and Without Sleep Disorder

BACKGROUND

Sleep problems are common in children with Tourette Syndrome (TS). However, research regarding their demographic and clinical profile is limited.

METHODS

We examined characteristics of 114 children aged five to 17 years with a lifetime diagnosis of TS and compared children with sleep disorder (n = 32) and without sleep disorder (n = 82). Parent report from the 2014 National Survey of the Diagnosis and Treatment of ADHD and Tourette Syndrome provided demographics and clinical information, other diagnosed disorders, medication use, TS severity, and impairment.

RESULTS

More children with TS with sleep disorder were from households with lower parental education (P < 0.01) and poverty (P = 0.04); had other diagnoses (P = 0.03), including obsessive-compulsive disorder (P < 0.01), oppositional defiant disorder or conduct disorder (P < 0.01), attention-deficit/hyperactivity disorder (ADHD) (P = 0.02), and autism (P = 0.03); and had ever used TS medication (P = 0.01) than children with TS without sleep disorder. More children with TS with sleep disorder had severe TS symptoms (P <0.01), tic-related impairment (P<0.01), and severe ADHD symptoms (P < 0.01) compared with children with TS without sleep disorder.

CONCLUSIONS

Findings suggest greater parent-reported impact and tic-related interference in children with TS with sleep disorder compared with TS without sleep disorder. Results underscore the importance of monitoring and intervention for TS exacerbations, other diagnosed disorders, and medication use, and consideration of socioeconomic context in sleep disorder management and prevention in children with TS.

Sleep Disturbance in Tourette's Disorder: Potential Underlying Mechanisms

Purpose of review

Sleep disturbance is common in TD. However, our understanding of the pathophysiological mechanisms involved is preliminary. This review summarizes findings from neuroimaging, genetic, and animal studies to elucidate potential underlying mechanisms of sleep disruption in TD.

Recent findings

Preliminary neuroimaging research indicates increased activity in the premotor cortex, and decreased activity in the prefrontal cortex is associated with NREM sleep in TD. Striatal dopamine exhibits a circadian rhythm; and is influenced by the suprachiasmatic nucleus via multiple molecular mechanisms. Conversely, dopamine receptors regulate circadian function and striatal expression of circadian genes. The association of TD with restless legs syndrome and periodic limb movements indicates shared pathophysiology, including iron deficiency, and variants in the BTDB9 gene. A mutations in the L-Histidine Decarboxylase gene in TD, suggests the involvement of the histaminergic system, implicated in arousal, in TD.

Summary

These biological markers have implications for application of novel, targeted interventions, including noninvasive neuromodulation, iron supplementation, histamine receptor antagonists, and circadian-based therapies for tic symptoms and/or sleep and circadian rhythms in TD.

Sleep Disorders and Sleep Problems in Patients With Tourette Syndrome and Other Tic Disorders: Current Perspectives

Sleep disorders seem to be a frequent complaint of patients diagnosed with Tourette syndrome (TS) or chronic or persistent tic disorders (CTD or PTD). In this review, we expanded a previously used search using 4 well-known databases up to February 15, 2022, looking for the coexistence of global and/or specific sleep disorders and polysomnographic studies performed on patients with TS/CTD/PTD. The references of interest in the topic were selected by hand. Sleep disorders in general, insomnia, different arousal disorders, the persistence of tics during sleep, excessive daytime sleepiness, and periodic limb movements during sleep (PLMS) were very frequent in patients with TS, most of them being more frequent in patients with comorbid Attention Deficit Hyperactivity Disorder. The most frequent results from polysomnographic studies were decreased sleep efficiency and increased sleep onset latency. Many of these findings could be related to medication used for the treatment of tics and comorbid disorders.

Tourette Disorder and Sleep

Healthy sleep is of utmost importance for growth, development, and overall health. Strong evidence shows that sleep is affected negatively in patients and particularly children with Tourette Disorder (TD). There is also a frequent association of TD with Attention Deficit Hyperactivity Disorder (ADHD) which alone has negative effects on sleep and cumulatively worsens the associated sleep findings. The most consistent polysomnographic findings in patients with TD is decreased total sleep time, lower sleep efficiency and an elevated arousal index. Polysomnography studies have confirmed the presence of movements and persistence of tics during both Rapid Eye Movement (REM) and NREM sleep [1]. In general Patients with TD are found to have an increased incidence of sleep onset and sleep maintenance insomnia. Some studies have shown increased incidence of parasomnias (including sleepwalking, sleep talking and night terrors), but this may be confounded by the increased underlying sleep disruptions seen in TD. The hypersomnolence found in patients with TD is also suggested to be secondary to the underlying TD sleep disruption. There is not a significant association with sleep disordered breathing or circadian rhythm disorders and TD. Treatment of underlying TD is important for the improvement of sleep related TD manifestations and is outlined in this review.

Overlapping sleep disturbances in persistent tic disorders and attention-deficit hyperactivity disorder: A systematic review and meta-analysis of polysomnographic findings

INTRODUCTION

Persistent tic disorders (PTDs) and attention-deficit hyperactivity disorder (ADHD) are common neurodevelopmental conditions which tend to co-occur. Both diagnoses are associated with sleep problems. This systematic review and meta-analysis investigates overlaps and distinctions in objective sleep parameters based on diagnosis (PTD-only, PTD + ADHD, and ADHD-only).

METHODS

Databases were searched to identify studies with objective sleep measures in each population. Meta-analyses were conducted using a random effects model.

RESULTS

Polysomnography was the only measure included in all three groups. Twenty studies met final inclusion criteria, combining PTD-only (N = 108), PTD + ADHD (N = 79), and ADHD-only (N = 316). Compared to controls (N = 336), PTD-only and PTD + ADHD groups had significantly lower sleep efficiency and higher sleep onset latency. PTD + ADHD also had significantly increased time in bed and total sleep time. No significant differences were observed between ADHD-only groups and controls.

DISCUSSION

Different sleep profiles appear to characterise each population. PTD + ADHD was associated with more pronounced differences. Further research is required to elucidate disorder-specific sleep problems, ensuring appropriate identification and monitoring of sleep in clinical settings.

Dream enactment behavior: review for the clinician

NONE

Dream enactment behavior commonly occurs on occasion in normal children and adults. Disruptive and frequent dream enactment behavior may come to the attention of the clinician either as the primary reason for consultation or as a prominent characteristic of a patient with other sleep disorders. Questioning patients with chronic neurologic and psychiatric disorders may also reveal previously unrecognized behavior. In the absence of sleep pathology, process of dream enactment likely begins with active, often emotionally charged dream content that may occasionally break through the normal REM sleep motor suppressive activity. Disrupted sleep resulting from many possible causes, such as circadian disruption, sleep apnea, or medications, may also disrupt at least temporarily the motor-suppressive activity in REM sleep, allowing dream enactment to occur. Finally, pathological neurological damage in the context of degenerative, autoimmune, and infectious neurological disorders may lead to chronic recurrent and severe dream enactment behavior. Evaluating the context, frequency, and severity of dream enactment behavior is guided first and foremost by a structured approach to the sleep history. Physical exam and selected testing support the clinical diagnosis. Understanding the context and the likely cause is essential to effective therapy.

Sleep disorders in tourette syndrome

Sleep disorders are very common in patients diagnosed with Tourette syndrome (TS). The present review focuses on sleep disorders and the results of polysomnographic studies performed in patients with TS. We made a search using the PubMed, Embase, MedLine, and Web of Science Databases, from 1966 until November 14, 2019, crossing the search term "Tourette syndrome" with "sleep", "sleep disorders", "sleep disturbances", and "polysomnography", and with each of the specific sleep disorders listed according to the International Classification of the Sleep Disorders-Third Edition. Then we identified the references of interest for the topic. Insomnia, excessive daytime sleepiness, disorders of arousal (sleepwalking, sleeptalking, sleep terrors, and enuresis), the persistence of tics during sleep, and presence of periodic limb movements during sleep (PLMS) were very frequent in patients with TS. These disturbances were more frequent in children and in patients with comorbid Attention Deficit Hyperactivity Disorder. Decreased sleep efficiency, decreased percentage of delta sleep, increased nocturnal awakenings and increased PLMS were the most consistent findings in the polysomnographic studies.

Sleep and Sleep Disorders in Tourette Syndrome: What is Known and What is Still Unknown

Background:

Most of the patients with Tourette Syndrome (TS) present additional comorbidities. Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive-Compulsive Disorder (OCD) are the most common. Sleep Disorder has been suggested also as common comorbidity.

Objective:

To review the literature on sleep characteristics and sleep disorder in patients with Tourette Syndrome (TS), with emphasis on the contribution of specific co-morbidities to the severity of impaired sleep and life quality of the patients.

Results:

In general, sleep problems are not frequent at the age when tics appear which are estimated to affect about 10 % of these children. In severe cases, tics appear in all sleep stages. In a large study, the prevalence of sleep problems was 17.8% but was 12 % in “TS-only” (9.4% in children and 7.5 in adults) compared to 22% in children and 18% in adults with TS+ADHD. Unfortunately, in most of the studies, the characteristics of these “sleep problems” are not defined. In spite of the scarcity of data, the two main sleep disorders in TS patients are insomnia and parasomnias. Although much more data is needed, many TS subjects are sleep deprived (which exacerbate the tics) and may suffer from excessive daytime sleepiness, which negatively affects normal functioning.

Conclusions:

Although the literature is not conclusive, children and adolescents with TS appear to suffer more from sleep disturbances and sleep disorders than age-matched controls. Not all patients have tics during sleep, but in severe cases, tics may appear in all sleep stages. It is clear that when patients present both TS and ADHD, (a very common condition), the sleep difficulties are related mainly to ADHD. Much more research is warranted in all aspects of sleep and sleep disorders in TS.

Sleep difficulties in children with Tourette syndrome and chronic tic disorders: a systematic review of characteristics and associated factors

Sleep difficulties are common in children and young people with Tourette syndrome and chronic tic disorders (TS/CTD). However, it is unclear whether sleep problems can be considered typical of the TS/CTD phenotype or whether they reflect concomitant factors such as individual patient characteristics (e.g. medication use), underlying neurodevelopmental disorders and/or co-occurring psychiatric symptoms. To help address this question, this review systematically explored types and frequency of sleep problems in children and young people with TS/CTD, while also examining the heterogeneity and methodological quality of studies. Psycinfo, Ovid Medline, Embase, and Web of Science databases were searched using a range of terms relating to tics, sleep and co-occurring psychopathology. Studies were considered that included a sample of children with TS/CTD (n &gt; 5) for whom sleep difficulties were measured. Eighteen studies met criteria for inclusion in the review. Findings supported the high prevalence of sleep difficulties in children with TS/CTD, though estimates of sleep difficulties ranged from 9.7% to 80.4%. Twelve studies reported on other factors affecting sleep in this patient group including tic severity, comorbid psychopathological or neurodevelopmental disorders and medication use. Studies varied in terms of methodology, sample characteristics and research quality, but most concluded that children with TS/CTD experienced high levels of sleep difficulties with children with co-occurring anxiety most at risk. The current review highlights the need for further empirical investigation of sleep in children with TS/CTS, with a view to informing understanding and clinical management.

Tourette Syndrome and Comorbid Neuropsychiatric Conditions

Tourette syndrome is a neuropsychiatric condition characterized by both motor and phonic tics over a period of at least 1 year with the onset in childhood or adolescence. Apart from the tics, most of the patients with Tourette syndrome have associated neuropsychiatric comorbidities consisting of attention deficit hyperactivity disorder, obsessive compulsive disorder, rage attacks, sleep issues, depression, and migraine. Patients may also have physical complications directly from violent motor tics which can rarely include cervical myelopathy, arterial dissection, and stroke. The purpose of this article is to review the associated neuropsychiatric comorbidities of Tourette syndrome with emphasis on recent research.

Sleep, anxiety and psychiatric symptoms in children with Tourette syndrome and tic disorders

OBJECTIVE

The current study evaluated the relationship between tic, sleep disorders and specific psychiatric symptoms (anxiety, depression, obsessive compulsive symptoms).

METHODS

Assessment of 36 consecutive children and adolescents with tic disorders included: the Yale Global Tic Severity Scale (YGTSS) to assess the severity of tic symptoms; the Self-administered scale for children and adolescents (SAFA) to evaluate the psychopathological profile; a specific sleep questionnaire consisting of 45 items to assess the presence of sleep disorders. An age and sex-matched control group was used for comparisons.

RESULTS

Sleep was significantly more disturbed in patients with tic disorders than in controls. Difficulties in initiating sleep and increased motor activity during sleep were the most frequent sleep disturbances found in our sample. Patients showed also symptoms of anxiety (SAFA A), depressed mood (SAFA D) and doubt-indecision (SAFA O). Additionally, difficulties in initiating sleep resulted associated with other SAFA subscales relative to obsessive-compulsive symptoms and depression symptoms. Furthermore, anxiety symptoms (SAFA A) resulted associated with increased motor activity during sleep.

CONCLUSIONS

Findings confirm literature studies reporting high frequency of sleep problems, anxiety and other psychopathological symptoms in patients with tic disorders, and support the hypothesis that intrusive thoughts and other emotional disturbances might disrupt the sleep onset of these patients. These results suggest the importance of a thorough assessment of sleep and psychiatric disturbances in patients with tic disorders.

Obsessive compulsive symptoms and sleep difficulties: exploring the unique relationship between insomnia and obsessions

BACKGROUND

Sleep complaints have been linked with Obsessive Compulsive Disorder (OCD), though there is a dearth of research exploring the association between a range of disturbed sleep indicators and obsessive compulsive symptoms (OCS). Two separate studies were conducted to rigorously investigate this relationship in further detail, considering a number of different sleep indices and also the heterogeneous nature of OCS.

METHODS

Study 1 (n = 167) examined the relationship between OCS and the gold standard self-report assessments for delayed bedtime, sleep quality, nightmares, and insomnia symptoms. Study 2 (n = 352) replicated the primary findings from Study 1 in an independent sample and with an alternative measure of OCD, which takes into account the different OCS dimensions.

RESULTS

Results revealed a significant, independent link between obsessions and insomnia symptoms, but not between insomnia and compulsions. When examining the different OCS dimensions, insomnia was again found to bear a specific relationship to obsessions, above and beyond that with the other dimensions. Although depression is often highly comorbid with both OCD and sleep disturbances, depressive symptoms did not explain the OCS-sleep relationship in either study, suggesting a unique association between obsessions and insomnia.

CONCLUSIONS

Findings indicate that high levels of intrusive thoughts exhibit a specific association with insomnia symptoms-one that is not observed with other OCS. Future research may help elucidate the mechanisms and causal nature of this relationship.

Sleep disorders in children with Tourette syndrome

BACKGROUND

The objective of this study was to determine the frequency, nature, and impact of sleep disorders in children and adolescents with Tourette syndrome and to raise awareness about their possible inclusion as a Tourette syndrome comorbidity.

METHODS

Using a prospective questionnaire, we interviewed 123 patients of age ≤21 years with a confirmed diagnosis of Tourette syndrome. Each completed questionnaire was then reviewed in accordance with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria for categorization to a form of sleep disorder.

RESULTS

Of the 123 patients with Tourette syndrome, 75 (61%) had comorbid attention deficit hyperactivity disorder and 48 (39%) had Tourette without attention deficit hyperactivity disorder. The sleep problems observed included problems in the nature of sleep, abnormal behaviors during sleep, and impact of sleep disturbances on quality of life. Within these cohorts, 31 (65%) of the 48 Tourette-only patients and 48 (64%) of the 75 Tourette + attention deficit hyperactivity disorder patients could fit into some form of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, coded sleep disorders. Of the 48 Tourette + attention deficit hyperactivity disorder patients with sleep disorders, 36 (75%) had insomnia signs, which could be explained by the co-occurrence of attention deficit hyperactivity disorder and high stimulant use. However, 10 (32%) of the 31 Tourette-only patients with sleep disorders had insomnia irrespective of attention deficit hyperactivity disorder or medication use.

CONCLUSIONS

Sleep problems are common in children with Tourette syndrome irrespective of comorbid attention deficit hyperactivity disorder, justifying their inclusion as a comorbidity of Tourette syndrome.

OX1 and OX2 orexin/hypocretin receptor pharmacogenetics

Orexin/hypocretin peptide mutations are rare in humans. Even though human narcolepsy is associated with orexin deficiency, this is only extremely rarely due to mutations in the gene coding prepro-orexin, the precursor for both orexin peptides. In contrast, coding and non-coding variants of the OX₁ and OX₂ orexin receptors have been identified in many human populations; sometimes, these have been associated with disease phenotype, although most confer a relatively low risk. In most cases, these studies have been based on a candidate gene hypothesis that predicts the involvement of orexins in the relevant pathophysiological processes. In the current review, the known human OX₁/HCRTR1 and OX₂/HCRTR2 genetic variants/polymorphisms as well as studies concerning their involvement in disorders such as narcolepsy, excessive daytime sleepiness, cluster headache, polydipsia-hyponatremia in schizophrenia, and affective disorders are discussed. In most cases, the functional cellular or pharmacological correlates of orexin variants have not been investigated—with the exception of the possible impact of an amino acid 10 Pro/Ser variant of OX₂ on orexin potency—leaving conclusions on the nature of the receptor variant effects speculative. Nevertheless, we present perspectives that could shape the basis for further studies. The pharmacology and other properties of the orexin receptor variants are discussed in the context of GPCR signaling. Since orexinergic therapeutics are emerging, the impact of receptor variants on the affinity or potency of ligands deserves consideration. This perspective (pharmacogenetics) is also discussed in the review.

To sleep or not to sleep: a systematic review of the literature of pharmacological treatments of insomnia in children and adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

This systematic review assessed current evidence on sleep medication for attention-deficit/hyperactivity disorder (ADHD) patients, to establish appropriate guidance for clinicians faced with prescribing such medications.

METHODS

Five articles (based on four pharmacological compounds) out of a total 337 were identified as evidence to guide pharmacological treatment of ADHD-related sleep disorders. Data regarding participant characteristics, measures of ADHD diagnosis, measures of sleep, and outcome data were extracted.

RESULTS

Zolpidem and L-theanine both displayed a poor response in reducing sleep latency and increasing total sleep time, however L-theanine did produce an increase in sleep efficiency. Zolpidem produced high levels of side effects, leading to the largest dropout rate of all five studies. Clonidine reduced insomnia; and melatonin also exhibited a positive response, with reduced sleep latency, higher total sleep time, and higher sleep efficiency.

CONCLUSIONS

There is a relative paucity of evidence for the pharmacological treatment of ADHD-related sleep disorders; therefore, further research should be conducted to replicate these findings and obtain reliable results.

A retrospective survey of childhood ADHD symptomatology among adult narcoleptics

OBJECTIVE

This study examined the retrospective history of childhood ADHD symptomatology in an adult narcoleptic population (Narcolepsy Group [NG]: n = 161) compared with a control group (CG: n = 117).

METHOD

Both groups completed the Wender Utah Rating Scale (WURS), a retrospective self-report questionnaire indicating the presence of childhood ADHD symptomatology in adults.

RESULTS

Childhood ADHD symptoms were significantly greater in NG than CG (p < .001). Joint prevalence calculations of childhood ADHD symptomatology in NG were more than 8 to 15 times greater than expected. Among NG, those individuals with a greater score on the WURS, indicative of childhood ADHD symptomatology, also had shorter sleep onsets on the Multiple Sleep Latency Test, a common objective measure of sleepiness, t(97) = -7.11, p < .05.

CONCLUSION

It appears that self-reported childhood ADHD symptomatology history among adult narcoleptics is common. Future research is warranted with adult narcoleptics to elucidate the true nature of this.

Prevalence of allergic rhinitis in patients with attention-deficit/hyperactivity disorder: a population-based study

Allergic rhinitis (AR) is common in children. Characteristic symptoms of AR may result in daytime inattention, irritability, and hyperactivity, which are also components of ADHD. Conflicting data in previous studies exist regarding the relationship between ADHD and AR. The aim of this study was to examine the prevalence and risk of AR in ADHD patients in Taiwan. We conducted a cross-sectional study using the National Health Insurance Research Database in Taiwan. The study subjects included 469 patients who received psychiatric care for ADHD in 2005 and the general population (n = 220,599). Distributions of age, gender, and living areas as well as allergic diseases in the general population and in the ADHD group were examined by χ2 tests. Multivariate logistic regression models were used to analyze the risk factors of AR. The prevalence of AR in ADHD group and the general population was 28.4 and 15.2%, respectively. The prevalence of asthma was 9.6% in ADHD group and 6.4% in the general population. Both the prevalence of AR (p < 0.001) and asthma (p = 0.008) was significantly higher in ADHD group than the general population. The multivariate logistic regression analysis showed that ADHD patients had an increased rate of AR than general population (OR = 1.83; 95% CI = 1.48-2.27; p < 0.0001), and asthma was strongly associated with AR (OR = 9.28; 95% CI = 8.95-9.63; p < 0.0001). Our data showed that ADHD patients had an increased rate of AR. Therefore, psychiatrists should be more aware of the comorbidity of AR when treating ADHD patients.

Tourette syndrome and other tic disorders

Tic disorders, including Tourette syndrome, are an intriguing group of paroxysmal movement abnormalities that begin in childhood, have a fluctuating course, are capable of causing psychosocial and physical problems, and often improve by early adulthood. These disorders are frequently associated with a variety of comorbid problems whose negative effects may exceed those of tics. Therapy is strictly symptomatic and usually includes educational, behavioral, and a variety of pharmacological therapies. Although there is strong evidence supporting an inherited basis, the precise genetic abnormality remains unknown. A proposed poststreptococcal autoimmune etiology remains controversial. Pathophysiologically, tics appear to arise from an alteration within cortico-striatal-thalamo-cortical circuits, but the definitive site is unknown. Evidence supports an abnormality of synaptic neurotransmission, likely involving the dopaminergic system.

Sleep problems and disorders among adolescents with persistent and subthreshold attention-deficit/hyperactivity disorders

STUDY OBJECTIVES

To investigate the sleep schedules, problems, and disorders among adolescents with persistent attention-deficit/hyperactivity disorder (ADHD) and those with partially remitted ADHD symptoms.

DESIGN

A case-control study.

SETTING

National Taiwan University and schools in Taipei Patients or Participants: The sample included 281 adolescents (male, 85.4%; 145 with persistent ADHD, 136 with subthreshold ADHD), aged 11 to 17, who were diagnosed with ADHD, according to DSM-IV criteria, at the mean age of 6.7 years (SD = 3.0) and 185 unaffected control subjects.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

We conducted psychiatric interviews of participants and their mothers using the Chinese Kiddie-Schedule for Affective Disorders and Schizophrenia-Epidemiology version for making the diagnoses of ADHD, other psychiatric disorders, and sleep problems or disorders. We also collected the medication treatment data and parent and teacher reports of ADHD-related symptoms. Our results showed that adolescents with a childhood diagnosis of ADHD according to DSM-IV criteria, regardless of persistent ADHD, were more likely to have current and lifetime sleep problems and sleep disorders according to DSM-IV (insomnia, sleep terrors, nightmares, bruxism, and snoring). The presence of at least 1 psychiatric comorbid condition increased the risks for insomnia and nightmares. The use of methylphenidate was not associated with further increased risk of sleep problems, except bruxism.

CONCLUSIONS

Our findings support a relationship between ADHD and sleep problems, which can be partially explained by the psychiatric comorbidities, but did not support a disturbed sleep schedule. Our study suggests that mental health professionals should screen for sleep problems and psychiatric comorbidities among adolescents with a childhood diagnosis of ADHD regardless of the severity of current ADHD symptoms.

Validation of the presence of comorbidities in a Danish clinical cohort of children with Tourette syndrome

Tourette syndrome (TS) is characterized by the presence of motor and vocal tics and is often accompanied by comorbid symptoms. We assessed the frequency of the comorbid symptoms obsessive-compulsive disorder obsessive-compulsive disorder, attention-deficit hyperactivity disorder (ADHD), rage attacks, sleeping disturbances, and depressive symptoms in a Danish clinical cohort of 314 children with TS using validated diagnostic instruments. For the assessment of symptoms of seasonal affective disorder and stuttering, we used a nonvalidated systematic interview. In total, only 10.2% of the children did not have any comorbid symptoms at all. If ADHD and/or obsessive-compulsive disorder were present, the rates of the comorbidities rage, symptoms of seasonal affective disorder, sleep disturbances, and depressive symptoms were significantly higher than if ADHD and/or obsessive-compulsive disorder were absent. The most severe tics were found in the group for which both ADHD and obsessive-compulsive disorder were present. Furthermore, there was a tendency toward more severe tics if other comorbid symptoms were present.

Sleep patterns in children with attention-deficit/hyperactivity disorder, tic disorder, and comorbidity

BACKGROUND

In children, attention-deficit/hyperactivity disorder (ADHD), tic disorder (TD), and their coexistence (ADHD + TD comorbidity) are very common and clinically important. Associated sleep patterns and their clinical role are still insufficiently investigated. This study aimed at characterizing these sleep patterns in children with ADHD, TD, and ADHD + TD comorbidity and determining whether, in ADHD + TD, the factors ADHD and TD may affect the sleep pattern in an independent (additive) or in a complex (interactive) manner.

METHOD

By means of polysomnography, sleep patterns were investigated in 4 groups of unmedicated 8.0-16.4-year-old children (healthy controls, ADHD-only, TD-only, and ADHD + TD). Each group consisted of 18 subjects matched for age, gender, and intelligence.

RESULTS

ADHD was primarily characterized by increase in rapid eye movement (REM) sleep, whereas TD patients displayed lower sleep efficiency and elevated arousal index in sleep. In children with ADHD + TD, both effects appeared. No interaction between the ADHD and TD factors was found for any of the sleep parameters. Significant correlations between sleep patterns and clinical symptoms were found.

CONCLUSIONS

ADHD and TD are characterized by specific sleep alterations. When coexisting, the two disorders alter the sleep pattern in an additive manner, suggesting a high impact on clinical and therapeutic perspectives.

REM-sleep alterations in children with co-existence of tic disorders and attention-deficit/hyperactivity disorder: impact of hypermotor symptoms

PURPOSE

To characterize precisely the sleep pattern in children with co-existence of TD + ADHD.

METHODS

By means of polysomnography, sleep pattern was investigated in 19 children with TD + ADHD unmedicated before and during study and 19 healthy controls, matched for age, gender, and intelligence.

RESULTS

Compared with healthy controls, children with TD + ADHD displayed shorter REM sleep latency and increased REM sleep duration. There was a negative correlational relationship between these REM-sleep alterations and they were determined by hyperactivity symptoms.

CONCLUSIONS

Sleep in children with coexistence of TD + ADHD may be characterized by an elevated REM sleep drive. Common mechanisms are suggested to underpin hypermotor symptoms and REM sleep regulation.

Schlafverhalten bei Kindern mit Tic-Störungen - eine polysomnographische Studie

Zusammenfassung: Fragestellung: Charakterisierung des Schlafmusters einer größeren Gruppe Kinder mit Tic-Störung sowie Untersuchung ob und wie Veränderungen des Schlafs mit der Schwere der Tic-Störung assoziiert sind. Methodik: Das Schlafverhalten von 25, zum Untersuchungszeitpunkt unmedizierten Kinder mit chronischer Tic-Störung wurde polysomnographisch untersucht und mit den Befunden von 22 gesunden Kontrollen verglichen. Zwischen beiden Gruppen bestanden keine Unterschiede hinsichtlich Alter, Geschlechtsverhältnis und Intelligenz. Ergebnisse: Kinder mit einer Tic-Störung zeigten eine reduzierte Schlafqualität sowie vermehrtes, bewegungsbezogenes Arousal im Vergleich zu gesunden Kontrollen. Hinsichtlich des Schlafs ging bei Kindern mit Tic-Störung eine schwerere Ausprägung der Tics mit häufigeren bewegungsbezogenen Arousals einher. Die Anzahl der kurzen, mit motorischen Phänomenen assoziierten Arousals korrelierte mit geringerer Schlafeffizienz, verzögertem Schlafbeginn und verlängerter Tiefschlaflatenz. Des weiteren bestimmten geringere Schlafeffizienz und verlängerte Tiefschlaflatenz bei Kindern mit Tic-Störung die Schwere der Tics am Tag. Schlussfolgerungen: Bei Kindern mit Tic-Störung scheint ein Zusammenhang zwischen den bewegungsbezogenen Arousals im Schlaf und der Ausprägung der Tics am Tag zu bestehen. Beeinträchtigungen des Schlafs bei Tic-Störungen könnten die Tic-Symptomatik am Tag verschlechtern.

Tourette syndrome: the self under siege

Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics--rapid, repetitive, stereotyped movements or vocalizations. Tourette syndrome typically has a prepubertal onset, and boys are more commonly affected than girls. Symptoms usually begin with transient bouts of simple motor tics. By age 10 years, most children are aware of nearly irresistible somatosensory urges that precede the tics. These urges likely reflect a defect in sensorimotor gating because they intrude into the child's conscious awareness and become a source of distraction and distress. A momentary sense of relief typically follows the completion of a tic. Over the course of hours, tics occur in bouts, with a regular intertic interval. Tics increase during periods of emotional excitement and fatigue. Tics can become "complex" in nature and appear to be purposeful. Tics can be willfully suppressed for brief intervals and can be evoked by the mere mention of them. Tics typically diminish during periods of goal-directed behavior, especially those that involve both heightened attention and fine motor or vocal control, as occur in musical and athletic performances. Over the course of months, tics wax and wane. New tics appear, often in response to new sources of somatosensory irritation, such as the appearance of a persistent vocal tic (a cough) following a cold. Over the course of years, tic severity typically peaks between 8 and 12 years of age. By the end of the second decade of life, many individuals are virtually tic free. Less than 20% of cases continue to experience clinically impairing tics as adults. Tics rarely occur in isolation, and other coexisting conditions--such as behavioral disinhibition, hypersensitivity to a broad range of sensory stimuli, problems with visual motor integration, procedural learning difficulties, attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depression, anxiety, and emotional instability--are often a greater source of impairment than the tics themselves. Emerging behavioral treatments of Tourette syndrome are based in part on an understanding of the moment-to-moment experience of somatosensory urges and motor response. With identification of specific genes of major effect and advances in our understanding of the neural circuitry of sensorimotor gating, habit formation, and procedural memory--together with insights from postmortem brain studies, in vivo brain imaging, and electrophysiologic recordings--we might be on the threshold of a deeper understanding of the phenomenology and natural history of Tourette syndrome.

Tourette syndrome and chronic tics in a sample of children and adolescents

Forty-eight subjects with Tourette syndrome (M 36, F 12; mean age 11.2 years) and 48 with chronic tic disorder (M 33, F 15; mean age 12.1 years) were recruited in order to study the vertical transmission within families of a vulnerability to tic disorders or to other psychiatric disorders, the role of adverse pre- and perinatal events, and the presence of comorbid psychiatric conditions. As control group, 30 matched, psychiatrically unaffected subjects (M 20, F 10; mean age 10.8 years) were chosen. Screening measures included detailed anamnestic data, focused on family history of tics and other psychiatric disorders, prenatal events and birth. Subjects and parents were also questioned about psychiatric comorbidity. Group differences were compared using Fisher Test. Subjects with Tourette syndrome and those with chronic tic were similar to each other and different from controls in family history of tic disorders, pre- and perinatal events, and some comorbid psychiatric disorders (attention deficit hyperactivity disorder, sleep problems, and mood disorders). Tourette syndrome and chronic tic group were different in family history of obsessive-compulsive disorder and in comorbidity for obsessive-compulsive disorder and other anxiety disorders. Tourette syndrome and obsessive-compulsive disorder were significantly associated in this sample. These findings seem to indicate that Tourette syndrome and chronic tic disorder are part of the same disease entity, with Tourette syndrome being a more severe and complex form of tic disorder.

The ADHD and sleep conundrum: a review

The relationship between attention-deficit hyperactivity disorder (ADHD) and sleep is a complex one that poses many challenges in clinical practice. Recent studies have helped to elucidate the nature of the brain mechanisms and neuromodulator systems underlying the theoretical associations among sleepiness, arousal, and attention. Studies of sleep disturbances in children with academic and behavioral problems have also underscored the role that primary sleep disorders such as obstructive sleep apnea hypopnea syndrome play in the clinical presentation of symptoms of inattention and behavioral dysregulation. In addition, new methodologies used in examining sleep and sleep patterns in children diagnosed with ADHD have shed further light on the prevalence, type, risk factors for, and impact of sleep disturbances in these children. The following discussion of the multilevel relationships among sleep quality and quantity, neurobehavioral functioning, and the clinical syndrome of ADHD expands on previous reviews of the literature and synthesizes what is currently known about the interaction of sleep and attention/arousal in children to propose possible underlying mechanisms, integrate more recent findings, and highlight important areas for future study. In addition, guidelines are provided for a clinical approach to evaluation and management of children with ADHD and sleep problems.

Variants of the orexin2/hcrt2 receptor gene identified in patients with excessive daytime sleepiness and patients with Tourette's syndrome comorbidity

The orexin-2/hypocretin-2 (OX2R) receptor gene is mutated in canine narcolepsy and disruption of the prepro-orexin/hypocretin ligand gene results in both an animal model of narcolepsy and sporadic cases of the human disease. This evidence suggests that the structure of the OX2R gene, and its homologue, the OX1R gene, both members of the G protein-coupled receptor (GPCR) family, and the gene encoding the peptide ligands, the prepro-orexin/hypocretin gene, may be variables in the etiology of sleep disorders. We report a single stranded conformational polymorphism (SSCP) analysis of the coding regions of these genes in idiopathic sleep disorder patients diagnosed with excessive daytime sleepiness (EDS) (n = 28), narcolepsy (n = 28), Tourette's syndrome/chronic vocal or motor tic disorder (n = 70), and control subjects (n = 110). Two EDS patients showed a Pro11Thr change. One Tourette's syndrome patient was found to have a Pro10Ser alteration. The Pro10Ser and Pro11Thr variants were not found in non-disease populations. Analysis of the ability of the mutant receptors to mobilize calcium compared to the wild-type receptor in response to orexin agonists indicated that they resulted in decreased potency at high (etaM) concentrations of orexin ligands. Further work is warranted to study the variability of the orexin/hypocretin system in a variety of disorders characterized by EDS.

Allergic rhinitis in children with attention-deficit/hyperactivity disorder

BACKGROUND

Both allergic rhinitis and attention-deficit/hyperactivity disorder (ADHD) are common pediatric conditions associated with learning difficulties and sleep disturbances. There are conflicting research data regarding the association between ADHD and atopic disorders.

OBJECTIVE

To determine the prevalence of allergic rhinitis in patients with physician-diagnosed ADHD.

METHODS

Patients 5 to 18 years of age who presented with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of ADHD to an outpatient pediatric psychiatry clinic were screened for allergic rhinitis with focused history, physical examination, and skin prick testing to common aeroallergens.

RESULTS

Thirty patients were interviewed, with 23 of these undergoing physical examination and skin prick testing. Eighty percent reported allergic rhinitis symptoms, whereas 61% had at least 1 positive prick skin test result. Forty-three percent showed typical physical signs of allergic rhinitis, 100% had a positive atopic family history, and 53% had other associated atopic disorders.

CONCLUSIONS

Most children with ADHD displayed symptoms and skin prick test results consistent with allergic rhinitis. Nasal obstruction and other symptoms of allergic rhinitis could explain some of the cognitive patterns observed in ADHD, which might result from sleep disturbance known to occur with allergic rhinitis. Therefore, evaluation and treatment of allergic rhinitis could benefit patients with ADHD.

Disturbed sleep in children with Tourette syndrome: a polysomnographic study

OBJECTIVE

To evaluate objective data on sleep quantity/quality and motor activity during night sleep in children with Tourette syndrome (TS).

METHOD

Polysomnography of 17 unmedicated TS children (ages: 7;11-15;5, mean: 11;10 years) without comorbid attention-deficit hyperactivity disorder (ADHD) was compared with 16 age-, sex- and IQ-matched healthy controls. Sleep analyses according to the procedure of Rechtschaffen and Kales were supplemented by counting epochs with short arousal-related movements (<or=15 s), thus allowing to calculate correlations between motor activity and sleep parameters.

RESULTS

Children with TS demonstrated changes in sleep parameters, including longer sleep period time, longer sleep latency, reduced sleep efficiency, and prolonged wakefulness after sleep onset. Their sleep profiles showed significantly more time awake and less sleep stage II. However, REM sleep variables, slow-wave sleep, and number of sleep stage changes were unaffected. Movement time was similar in both groups, but epochs with short arousal-related movements were increased in TS. Further analyses showed no significant correlations between sleep parameters and nighttime nontic movements, level of psychopathology or tic severity during daytime. Periodic limb movements during sleep (PLMS) were only seen in one TS patient (low PLMS index of 7.8/h).

CONCLUSIONS

Children with TS have disturbed sleep quality with increased arousal phenomena, which both may be intrinsic to the disorder and might trigger tics and other behavioral problems during daytime. This indicates the need for sleep evaluation in patients with TS.

Schlafstörungen bei kinder- und jugendpsychiatrischen Erkrankungen

Zusammenfassung: Schlafstörungen als Symptom zahlreicher kinder- und jugendpsychiatrischer Störungsbilder komplizieren häufig den Verlauf und die Behandlung der Grunderkrankung. Organische Störungen wie die Narkolepsie oder das Kleine-Levin-Syndrom können zu differentialdiagnostischen Schwierigkeiten und Fehleinschätzungen führen. Unklar ist, ob spezifische Veränderungen der Schlafarchitektur bereits im Kindes- und Jugendalter bestehen und damit als biologischer Trait-Marker für psychiatrische Erkrankungen zu verstehen sind. Während für das Erwachsenenalter die Bedeutung von Schlafstörungen vor allem für die Entwicklung späterer depressiver Störungen belegt werden konnte, ist derzeit offen, ob es sich bei persistierenden Schlafstörungen im Kindesalter um Vulnerabilitätsmarker für psychiatrische Erkrankungen handelt. In der vorliegenden Literaturübersicht sollen Wechselwirkungen zwischen Schlafstörung und psychischer Störung aufgezeigt und die Bedeutung der Berücksichtigung von Schlafstörungen für Diagnostik und Therapie kinder- und jugendpsychiatrischer Störungsbilder unterstrichen werden.

Sleep disturbances associated with attention deficit hyperactivity disorder: the impact of psychiatric comorbidity and pharmacotherapy

OBJECTIVE

To estimate the relative risk of sleep problems associated with attention deficit hyperactivity disorder (ADHD), its pharmacotherapy, and its comorbid psychopathology.

METHOD

Standard sleep questionnaires were used to assess sleep problems and characteristics in ADHD (n = 122) and non-ADHD (n = 105) comparison youths.

RESULTS

ADHD was associated with 10 of 19 sleep problems assessed. However, after controlling for psychiatric comorbidity and pharmacotherapy with stimulants, the majority of these differences were no longer evident. Rather, treatment with stimulants and comorbidity with anxiety and behavior disorders were significantly associated with sleep disturbances. Positive family history of ADHD was associated with none of the sleep problems assessed here after adjusting for age, psychiatric comorbidity, and treatment with anti-ADHD medication.

CONCLUSIONS

Although subjective sleep difficulties are common in ADHD youths, they are frequently accounted for by comorbidity and pharmacotherapy. Furthermore, the lack of an association between a positive family history of ADHD and sleep difficulties suggests that ADHD is not a misdiagnosis of the consequences of disruption of normal sleep.

Sleep-related disorders in neurologic disease during childhood

Sleep disorders commonly are associated with neurologic disorders in childhood. This review discusses primary sleep disorders that affect children with primary neurologic diseases. Primary sleep disorders are discussed as they relate to the primary neurologic disease. In addition, sleep disorders secondary to neurologic disorders commonly seen in the practice of pediatric neurology are reviewed. A useful sleep history to improve diagnostic and therapeutic interventions is outlined.

Sleep disturbances in children with attention-deficit/hyperactivity disorder: a comparative study with healthy siblings

The sleep profiles of 13 children with attention-deficit/hyperactivity disorder (ADHD) who were treated with a fixed dose of methylphenidate for at least 1 month were compared with those of 16 healthy siblings. Sleep disturbances were assessed according to a structured sleep questionnaire, and the severity of ADHD was evaluated via the Conners Parents Teachers Rating Scale. The results indicated that significantly more children with ADHD demonstrated single or multiple sleep disturbances as well as higher rates of specific sleep disorders, such as initial and middle insomnia, compared with their siblings. No correlation was found between the severity of ADHD and disturbed sleep. Sleep duration and satisfaction with sleep were similar in the two groups. These findings raise important questions regarding the association between ADHD and disturbed sleep.

Attention deficit hyperactivity disorder in the presence of Tourette syndrome

Increasing attention to comorbidity in Tourette syndrome has led to a search for factors that would help in the development of treatment strategies for attention deficit hyperactivity disorder. Despite arguments and some research supporting various viewpoints, it is still unclear to what extent the frequency of co-occurrence is high in Tourette syndrome. It also is unclear whether attention deficit hyperactivity disorder and obsessive-compulsive disorder are part of a spectrum with related genetic or environmental factors. One of the main difficulties is obtaining a truly representative community sample and agreeing upon the categorical boundaries. The consequences of this argument are discussed. Effective treatment of attention deficit hyperactivity disorder in the presence of tics and Tourette syndrome has undergone considerable change from an absolute contraindication of stimulants to cautious use. For those whom stimulants fail or produce unacceptable side effects, nonstimulant medications are available in increasing variety. Much more methodologically adequate research needs to be undertaken with them.

Practitioner review: assessment and treatment of sleep disorders in children and adolescents

Sleep disorders in children are diverse in type, common, often serious in their effects yet neglected in professional education. They complicate many psychiatric disorders and can cause various cognitive and behavioural problems as well as more widespread difficulties in the family as a whole. Accurate assessment allows an appropriate choice from the various types of treatments that are now available but often under used. Diagnostic points and treatment approaches are outlined for the three main categories of childhood sleep disorder: sleeplessness; excessive sleepiness; and episodic disturbances related to sleep (parasomnias). The need for more widespread awareness of and provision for sleep disorders is emphasized.

Childhood sleep disorders

Sleep problems in children may differ in various ways from analogous problems in the adult. This is less because of neurophysiologic differences between the two groups than it is because of the child's greater level of dependency. Young children make few decisions on their own and, as a result, parent-child interactions become connected intimately to the child's sleep process at bedtime and throughout the night. Parental desires and expectations are at least as important as those of the child in determining the pattern of sleep that follows. Such interactions are most important when it comes to understanding causes of sleeplessness in the young child, and only by appreciating these interactions can the clinician serve a useful role in helping the family to understand and improve a young child's problematic sleep patterns.

[The influence of sleep on abnormal waking movements]

Sleep decreases considerably the abnormal movements seen during waking in the degenerative extra-pyramidal diseases. However, the electrophysiologic recordings reveal that muscular contractions are not completely abolished. This decrease parallels the reduction of the waking system which act likely as a non-specific system of amplification. One can notice that sleep modifies the characteristics of the parkinsonian tremor and that some palatal myoclonias persist during sleep.

Tic disorders

This article has provided an approach to patients who present with Tourette's syndrome or other tic disorders. The goals are to clarify each of the problems, to determine whether the major source of distress is related to tics or associated behaviors, and to develop an individualized multimodal treatment program. A valuable source of additional information for physicians, parents, and patients is the voluntary nonprofit Tourette Syndrome Association, 42-40 Bell Blvd, Bayside, NY 11361-9596.