Is there a specific polysomnographic sleep pattern in children with attention deficit/hyperactivity disorder?

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.

Study design, baseline patient characteristics and intervention in a cross-cultural framework: results from the ADORE study

OBJECTIVE

To describe the methodology and to present the baseline findings of the Attention-deficit/hyperactivity Disorder Observational Research in Europe (ADORE) study, the primary objective of which is to describe the relationship between treatment regimen prescribed and quality of life of children with ADHD in actual practice.

METHODS

In this 2-year prospective observational study, data on diagnosis, prescribed treatment and outcomes of ADHD were collected at seven time points by paediatricians and child psychiatrists on 1,573 children recruited in 10 European countries. The data presented here from the 1,478 patients included in the analyses describe the baseline condition, initial treatment regimen prescribed and quality of life of families with children with ADHD.

RESULTS

Patients had a mean age of 9.0 years (SD 2.5) and 84% were male. Physicians diagnoses were made using DSM-IV (43%), ICD-10 (32%) and both DSM-IV and ICD-10 (12%). Mean age of awareness of a problem was 5.1 years, suggesting an average delay of approximately 4 years between awareness and diagnosis of ADHD. Baseline ADHD rating scale scores (physician-rated) indicated moderate to severe ADHD. Parent-rated SDQ scores were in agreement and suggested significant levels of co-existing problems. CGI-S, CGAS and CHIP-CE scores also indicated significant impairment. Patients were offered the following treatments after the initial assessment: pharmacotherapy (25%), psychotherapy (19%), combination of pharmacotherapy and psychotherapy (25%), other therapy (10%) and no treatment (21%).

CONCLUSION

The ADORE study shows that ADHD is similarly recognised across 10 European countries and that the children are significantly impaired across a wide range of domains. In this respect, they resemble children described in previous ADHD samples.

Sleep and COMT polymorphism in ADHD children: preliminary actigraphic data

OBJECTIVE

To examine whether COMT (catechol-O-methyltransferase) polymorphism modulates aspects of sleep in children diagnosed with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Nightly sleep actigraphic recordings during a double-blind, placebo-controlled, crossover clinical study (1 week of 0.5 mg/kg MPH; 1 week of placebo) were obtained for 34 children, 7.4 to 12 years old, diagnosed with ADHD (DSM-IV). Diagnosis was generated by the Diagnostic Interview Schedule for Children and was confirmed by multidisciplinary consensus.

RESULTS

Children who were Val allele carriers had poorer sleep continuity compared with children with the Met-Met genotype while receiving a placebo and while receiving methylphenidate.

CONCLUSIONS

The findings of the present study support the hypothesis that sleep disturbances in children with ADHD are related to the underlying pathophysiology of the disorder.

Sleep in children with attention-deficit hyperactivity disorder: a meta-analysis of polysomnographic studies

The links between sleep and attention-deficit hyperactivity disorder (ADHD) have been a topic for intense ongoing research and clinical interest. Previous narrative literature reviews conveyed a consensus that parents of children with ADHD are more likely to report sleep problems in their children in comparison to parents of control children. However, when objective measures are considered the results appear to be more complex and inconsistent. This review is based on a meta-analysis of relevant polysomnographic studies. We assessed measures related to sleep architecture, breathing disorders, and periodic limb movements in sleep (PLMS), and the role of potential moderators such as age, gender, and other methodological factors. The meta-analysis revealed only one significant combined effect that indicates that children with ADHD are more likely than controls to suffer from PLMS. Factors such as age, gender, inclusion of adaptation night, and comorbidity appear to play a moderating role in the associations between sleep characteristics and ADHD. To provide new insight regarding the links between sleep and ADHD research in this field should adopt new strict guidelines and consider the role of multiple pertinent moderating factors.

Attention deficit disorders: are we barking up the wrong tree?

Attention deficit disorder (AAD) and attention deficit/hyperactivity disorder (ADHD) are very frequent and protean developmental disorders without a definite biologic marker. This review proposes a framework to understand the enlarged spectrum of its manifestations based on current knowledge of the mechanisms underlying arousal and attention variations during sleep/wake cycle. The neuro-modulation's pivotal role in this process as well as in the fine tuning of synaptic architecture during development must be taken into account when trying to understand the marked fuzziness of the symptoms and the very high prevalence of reported co-morbidities. The series of related interactions includes a cyclic deactivation of the dorso-lateral portion of the prefrontal cortex (DLPFC) during sleep, suspending executive functions, co-occurring with rhythmic periods of decreased noradrenergic tonus. A protracted unbalance in modulation, with catecholaminergic relative deficiency, could explain less-than-optimum waking DLPFC activation and the most important manifestations of ADD. Beside the well documented dopaminergic effects of stimulant medication used in ADD and ADHD, a more important role must be assigned to noradrenaline (NA). At this light hyperactivity and impulsivity are less important dimensions. Rather, an attention deficit spectrum disorder should probably be regarded as a complication of a core defect in prefrontal cortex dependent inhibitory control, underlying inattention.

Modeling attention-deficit/hyperactivity disorder: a critical appraisal of the cognitive-energetic model

A number of theoretical models of attention-deficit/hyperactivity disorder (ADHD) have emerged in recent years that may be used as systematic guides for clinical research. The cognitive-energetic model (CEM) proposes that the overall efficiency of information processing is determined by the interplay of three levels: computational mechanisms of attention, state factors, and management/executive function (EF). The CEM encompasses both top-down and bottom-up processes and draws attention to the fact that ADHD causes defects at all three levels. These include cognitive mechanisms, such as response output; energetic mechanisms, such as activation and effort; and management/EF deficits. Increasing evidence suggests that inhibition deficits associated with ADHD may, at least in part, be explained in terms of an energetic dysfunction. The activation and effort energetic pools appear most relevant to ADHD, being directly related to response organization; however, further testing of CEM is critically dependent on the development of direct measures of these energetic pools. The CEM is a comprehensive model of ADHD but is not without limitations. In particular, further research is required to define more specifically the relationship between process dysfunction and state dysregulation in ADHD.

Dyssomnia in children diagnosed with attention deficit hyperactivity disorder: a critical review

OBJECTIVE

Studies prior to 1999 reported prevalent sleep disturbances in children diagnosed with attention deficit hyperactivity disorder (ADHD). However, these reports were largely inconclusive and inconsistent in their findings, hence the current review based on studies published thereafter.

METHOD

An online research of the National Library of Medicine and the Cochrane Library was conducted using the terms 'attention deficit hyperactivity disorder', 'sleep', 'human', and 'English language'.

RESULTS

Sixteen articles met the search criteria with 10 reporting objective measures of sleep characteristics (i.e. polysomnography, actigraphy, and/or video recording). These studies confirm an increase of rapid eye movement (REM) sleep latency and a proportional decrease of REM sleep in children diagnosed with ADHD. Stimulant treatment appears to have little effect on sleep quality while parent's reports of poor sleep in their ADHD-diagnosed offspring was largely inconsistent with the objective measures.

CONCLUSIONS

The review demonstrated a link between disturbances in sleep architecture and ADHD. Whether this is of an intrinsic or extrinsic cause remains debateable, as both behavioural (parental reporting) and physiological (objective differences in sleep architecture) factors are indicated. The effect of stimulant medication on sleep also requires further research, as current evidence is limited by study design.

Update: attention deficit/hyperactivity disorder in the primary care office

PURPOSE OF REVIEW

Attention-deficit/hyperactivity disorder (AD/HD) affects 7.5% of children, making it among the more common behavioral disorders of childhood. Pediatricians increasingly are expected to recognize AD/HD, as well as diagnose and manage it in the primary care setting. This article reviews recent developments in the care of the pediatric AD/HD patient, with emphasis on information enhancing primary care management.

RECENT FINDINGS

Studies published in 2004 provide evidence to guide the treatment of AD/HD. The AD/HD literature continues to support the important role of genetics in its etiology. The absence of universal genetic or neuroimaging findings indicates that history from multiple sources and physical exam remain the standard diagnostic method. Comorbid medical problems, such as sleep disruption and growth suppression, continue to be better understood in the setting of AD/HD, as do the substantial impacts of comorbid learning and psychiatric disorders. Despite great interest in alternative, nonstimulant and behavioral treatments, methylphenidate and amphetamine-based medications remain the mainstay of AD/HD intervention.

SUMMARY

AD/HD is a common medical condition with implications for long-term safety and life function, such as academic success, accident occurrence, and drug use. Identification and treatment is increasingly based in the primary care office, where children must be monitored for co-occurring disorders and referred for additional supports when necessary. Tools and guidelines provided by the American Academy of Pediatrics (AAP) provide a framework for consistent and competent AD/HD care supported by current evidence.

Whither causal models in the neuroscience of ADHD?

In this paper we examine the current status of the science of ADHD from a theoretical point of view. While the field has reached the point at which a number of causal models have been proposed, it remains some distance away from demonstrating the viability of such models empirically. We identify a number of existing barriers and make proposals as to the best way for these to be overcome in future studies. These include the need to work across multiple levels of analysis in multidisciplinary teams; the need to recognize the existence of, and then model, causal heterogeneity; the need to integrate environmental and social processes into models of genetic and neurobiological influence; and the need to model developmental processes in a dynamic fashion. Such a model of science, although difficult to achieve, has the potential to provide the sort of framework for programmatic model-based research required if the power and sophistication of new neuroscience technologies are to be effectively exploited.

EUNETHYDIS -- searching for valid aetiological candidates of Attention-Deficit Hyperactivity Disorder or Hyperkinetic Disorder

BACKGROUND

To step up research in ADHD, exchange of ideas, working together on key theoretical models and cooperative studies are necessary.

OBJECTIVE

To report about a European approach with strong links to the rest of the world.

METHOD

European Network on Hyperkinetic Disorders (Eunethydis) studies of Attention -- Deficit Hyperactivity Disorder (ADHD) or Hyperkinetic Disorder (HKD) is briefly reviewed in the context of the international effort to discover the aetiology of the disorder.

RESULTS

There are promising neurobiological, neurophysiological and neuropsychological candidates to explain the nature of ADHD/HKD.

CONCLUSION

Eunethydis has shown to be a fruitful platform for ADHD research and has good resources for its further development.

Sleep in children with attention-deficit hyperactivity disorder (ADHD): a review of naturalistic and stimulant intervention studies

Attention-Deficit Hyperactivity Disorder (ADHD) is the most common behavioral disorder of childhood. Multiple clinical and research reports suggest extensive sleep disturbances in children with ADHD, however, current data is contradictory. This paper reviewed 47 research studies (13 stimulant intervention and 34 naturalistic) on ADHD that were published since 1980. The main objectives of this review were to provide pediatric clinicians and researchers a clear and concise summary of published sleep data in children with ADHD, to provide a more accurate description of the current knowledge of the relationship between sleep and ADHD, and to provide current information on the effect of stimulant medication on sleep. Twenty-five of the reviewed studies used subjective reports of sleep, six were actigraphic studies, and 16 were overnight polysomnographic sleep studies (two of which also included Multiple Sleep Latency Tests). All participants were between the age of 3 and 19, and 60% were male. The results indicate high rates of parental reports of sleep disturbances in medicated and unmedicated children with ADHD, however, the majority of these findings have not been confirmed by objective sleep data. Although, agreement among objective studies is not absolute, the data suggest increased nighttime activity, reduced rapid eye movement sleep, and significant daytime somnolence in unmedicated children with ADHD when compared to controls. Data also suggest a possible increased prevalence of periodic limb movements in sleep in children with ADHD, however, little differences in sleep-disordered breathing. The limited number of studies, small and heterogeneous samples, and other methodological limitations make definite results difficult to determine. Future research will need to further clarify the relationship between sleep and ADHD and the effects of stimulants on sleep of children with ADHD.