An investigation of sleep characteristics, EEG abnormalities and epilepsy in developmentally regressed and non-regressed children with autism

Altered Intermittent Rhythmic Delta and Theta Activity in the Electroencephalographies of High Functioning Adult Patients with Autism Spectrum Disorder

Background: Autism spectrum disorder (ASD) is often associated with epilepsy. Previous studies have also shown increased rates of electroencephalographic (EEG) alteration in ASD patients without epilepsy. The aim of this study was to compare the rate of intermittent rhythmic delta and theta activity (IRDA/IRTA) events between high-functioning adult patients with ASD and matched healthy controls.

Materials and Methods: Routine EEG records of 19 ASD patients and 19 matched controls were screened for IRDA/IRTA using a fully data driven analysis with fixed thresholds. IRDA/IRTA rates before and after hyperventilation (HV) as well as the HV-induced difference in IRDA/IRTA rates (HV difference) were analyzed. For inter-group measures, we used the Wilcoxon rank sum test.

Results: Significantly increased HV difference was detected in the ASD group (p = 0.0497). However, the groups showed no difference in IRDA/IRTA rates before HV (p = 0.564) and after HV (p = 0.163).

Conclusions: The lack of any group differences regarding IRDA/IRTA before HV might be related to the fact that we only studied non-secondary high-functioning autism in a small sample of epilepsy-free adult patients. A significantly increased HV difference might be regarded as a marker of subtle neuronal network instability possibly causing short-term disturbances via local area network inhibition and long-term effects via epileptic encephalopathy.

Recommendations for Identifying Sleep Problems and Treatment Resources for Children with Autism Spectrum Disorder

Many young children experience sleep problems that may influence their daytime functioning. These sleep problems are especially prevalent in young children with autism spectrum disorder (ASD). Therefore, general recommendations for identifying and treating sleep problems in children with ASD are needed for behavior analysts to identify potential sleep problems and make empirically informed decisions regarding treatment options. The current paper seeks to provide behavior analysts, who work with children with ASD, with informative research on pediatric sleep problems, sleep measures, and options for behavioral sleep treatment.

Epilepsy and Autism

Epilepsy and autistic spectrum disorder frequently coexist in the same individual. Electroencephalogram (EEG) epileptiform activity is also present at a substantially higher rate in children with autism than normally developing children. As with epilepsy, there are a multitude of genetic and environmental factors that can result in autistic spectrum disorder. There is growing consensus from both animal and clinical studies that autism is a disorder of aberrant connectivity. As measured with functional magnetic resonance imaging (MRI) and EEG, the brain in autistic spectrum disorder may be under- or overconnected or have a mixture of over- and underconnectivity. In the case of comorbid epilepsy and autism, an imbalance of the excitatory/inhibitory (E/I) ratio in selected regions of the brain may drive overconnectivity. Understanding the mechanism by which altered connectivity in individuals with comorbid epilepsy and autistic spectrum disorder results in the behaviors specific to the autistic spectrum disorder remains a challenge.

Counting Sheep: Sleep Disorders in Children With Autism Spectrum Disorders

INTRODUCTION

This article will discuss the prevalence and types of sleep disorders experienced by children with autism spectrum disorders (ASDs), the risk factors for the development of sleep disorders among children with ASDs, the impact of sleep disorders on children with ASDs, and the role of the primary care provider (PCP) in diagnosing and treating sleep disorders among children with ASDs.

METHOD

Review of published literature on the topic.

RESULTS

Children with ASDs are at risk for the development of chronic sleep disorders, which can have a negative impact on behavior. Both behavioral and pharmacological interventions exist for the treatment of sleep disorders among children with ASDs, with supplemental melatonin being the most widely studied and proven treatment.

DISCUSSION

PCPs will care for children with ASDs. Therefore, it is vital for PCPs to be knowledgeable about this topic and to promptly assess for and manage sleep disorders among children with ASDs.

Sleep problems are more frequent and associated with problematic behaviors in preschoolers with autism spectrum disorder

BACKGROUND

Children with autism spectrum disorder (ASD) often suffer from sleep problems that in turn correlate with behavioral problems. However, in Japan, there have been few studies of sleep problems in children with ASD.

AIMS

This study compared sleep problems in preschoolers from the community and preschoolers with ASD in Japan, and examined whether sleep problems were related to problematic behaviors in ASD preschoolers.

METHODS AND PROCEDURES

Sleep problems were assessed in 965 community and 193 ASD preschoolers using the Japanese Sleep Questionnaire for Preschoolers, which was developed to assess sleep problems in Japanese preschoolers. Behavioral problems were assessed in 107 ASD preschoolers using the Child Behavior Checklist.

OUTCOMES AND RESULTS

Compared with community preschoolers, ASD preschoolers experienced significantly more sleep problems, including obstructive sleep apnea and parasomnias. ASD preschoolers with sleep problems exhibited more behavioral problems than those without sleep problems. The severity of sleep problems, especially insomnia, was significantly correlated with behavioral problems in ASD preschoolers.

CONCLUSIONS AND IMPLICATIONS

The present study suggests that sleep problems, especially obstructive sleep apnea, are more common in ASD preschoolers than in community preschoolers. The study also shows that sleep problems, especially insomnia, are related to problematic behavior in ASD preschoolers.

Sleep in Neurodevelopmental Disorders

Individuals with intellectual and developmental disabilities (IDD) experience sleep problems at higher rates than the general population. Although individuals with IDD are a heterogeneous group, several sleep problems cluster within genetic syndromes or disorders. This review summarizes the prevalence of sleep problems experienced by individuals with Angelman syndrome, Cornelia de Lange syndrome, Cri du Chat syndrome, Down syndrome, fragile X syndrome, Prader-Willi syndrome, Smith-Magenis syndrome, Williams syndrome, autism spectrum disorder, and idiopathic IDD. Factors associated with sleep problems and the evidence for sleep treatments are reviewed for each neurodevelopmental disorder. Sleep research advancements in neurodevelopmental disorders are reviewed, including the need for consistency in defining and measuring sleep problems, considerations for research design and reporting of results, and considerations when evaluating sleep treatments.

Influence of sleep disorders on the behavior of individuals with autism spectrum disorder

The aim of this study was to investigate the correlation between sleep disorders and the behavior of subjects with autism spectrum disorder (ASD) and control subjects using specific questionnaires. A small percentage (1.8%) of the control subjects had symptoms indicative of sleep-breathing disorders (SBD) and nocturnal sweating. Fifty-nine percent of the subjects with ASD had symptoms indicative of at least one sleep disorder, with SBD the most commonly reported (38%). In the control group, the symptoms of SBD were correlated with social, thought, attentional, aggression, externalizing and behavioral problems. In the ASD group, disorders of arousal (DA) were correlated with thinking problems, and disorders of excessive somnolence were correlated with thinking and behavioral problems. These results suggest that children and adolescents with ASD have a high frequency of sleep disorders, which in turn correlate with some of the behavioral traits that they already exhibit. Furthermore, sleep disturbances, when present in the typically developing children, also correlated with behavioral problems.

Clinical characteristics of children and young adults with co-occurring autism spectrum disorder and epilepsy

The association between autism spectrum disorder (ASD) and epilepsy has been described for decades, and yet we still lack the full understanding of this relationship both clinically and at the pathophysiologic level. This review evaluates the available data in the literature pertaining to the clinical characteristics of patients with autism spectrum disorder who develop epilepsy and, conversely, patients with epilepsy who develop autism spectrum disorder. Many studies demonstrate an increased risk of epilepsy in individuals with ASD, but rates vary widely. This variability is likely secondary to the different study methods employed, including the study population and definitions of the disorders. Established risk factors for an increased risk of epilepsy in patients with ASD include intellectual disability and female gender. There is some evidence of an increased risk of epilepsy associated with other factors such as ASD etiology (syndromic), severity of autistic features, developmental regression, and family history. No one epilepsy syndrome or seizure type has been associated, although focal or localization-related seizures are often reported. The age at seizure onset can vary from infancy to adulthood with some evidence of a bimodal age distribution. The severity and intractability of epilepsy in populations with ASD have not been well studied, and there is very little investigation of the role that epilepsy plays in the autism behavioral phenotype. There is evidence of abnormal EEGs (especially epileptiform abnormalities) in children with ASD even in the absence of clinical seizures, but very little is known about this phenomenon and what it means. The development of autism spectrum disorder in patients with epilepsy is less well studied, but there is evidence that the ASD risk is greater in those with epilepsy than in the general population. One of the risk factors is intellectual disability, and there is some evidence that the presence of a particular seizure type, infantile spasms, may increase risk, but some of the data are conflicting. We believe that one of the reasons that so little is known about this phenomenon is the lack of cross talk between researchers and clinicians alike in the two fields. We conclude that large systematic studies that employ strict ascertainment of samples using standardized definitions of both disorders, validated data collection tools, and appropriate longitudinal follow-up are needed to better shed light on certain clinical aspects of the comorbidity of ASD and epilepsy. Ideally, we could provide the optimal diagnostic and treatment services to these patients in a multidisciplinary setting with both epilepsy and neurobehavioral specialists. This article is part of a Special Issue entitled "Autism and Epilepsy".

Sleep in Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder

Sleep problems are common in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Sleep problems in these disorders may not only worsen daytime behaviors and core symptoms of ASD and ADHD but also contribute to parental stress levels. Therefore, the presence of sleep problems in ASD and ADHD requires prompt attention and management. This article is presented in 2 sections, one each for ASD and ADHD. First, a detailed literature review about the burden and prevalence of different types of sleep disorders is presented, followed by the pathophysiology and etiology of the sleep problems and evaluation and management of sleep disorders in ASD and ADHD.

Interictal epileptiform activity and autism

Many individuals with autism have epileptiform discharges on their EEG without having definite clinical seizures. The clinical significance of epileptiform activity in patients with autism is controversial. Some consider it an epiphenomenon of the underlying condition that should be ignored, and others believe that frequent spikes may contribute to the cognitive impairment and advocate treatment. Several studies have reported variable rates of epileptiform activity and variable response to treatment. There is an urgent need to conduct controlled clinical trials to assess the true incidence of epileptiform activity in children with autism, develop a risk assessment model, and study the effectiveness of treatment. This article is part of a Special Issue entitled "Autism and Epilepsy".

Sleep in Neurodevelopmental and Neurodegenerative Disorders

There is a close relationship between sleep and childhood neurodevelopmental/neurodegenerative disorders. Understanding the sleep issues may provide greater insight into pathophysiology and treatment of these disorders.

Sleep in high-functioning children with autism: longitudinal developmental change and associations with behavior problems

Sleep disturbance is common in autism spectrum disorder (ASD), but longitudinal trajectories are poorly defined. This study measured sleep disturbance at baseline and 1 year later examining change over time and associated problem behaviors. Participants were 84 gender-matched children, aged between 7 and 12 years at baseline; 46 children were diagnosed with ASD, and 38 were typically developing (TYP) children. Parent reports on a range of scales were collected. The ASD group had more sleep disturbance than the TYP group. Sleep disturbance decreased over the year in children with ASD, but not in TYP children. Reduced sleep disturbance was associated with improved social ability. Sleep disturbance at baseline predicted later anxiety. Findings indicated different trajectories of sleep disturbance in ASD, and the implications are discussed.

Childhood autism spectrum disorders with and without epilepsy: clinical implications

This prospective cross-sectional study compared 25 children with pervasive developmental disorder and epilepsy and 25 children having pervasive developmental disorder without epilepsy on pervasive developmental disorder scores, Childhood Autism Rating Scale scores, language disability, presence of regression, and epileptiform abnormalities. Epilepsy phenotype was also studied. Children with pervasive developmental disorder and epilepsy had higher pervasive developmental disorder scores (P = .001), higher Childhood Autism Rating Scale scores (P = .016), and lower social quotient (P = .09). More than 50% of children with pervasive developmental disorder and epilepsy and 12% of children having pervasive developmental disorder without epilepsy had epileptiform abnormalities in electroencephalography (EEG). Regression of milestones was significantly associated with epilepsy and epileptiform abnormalities. Children with pervasive developmental disorder and epilepsy might have a worse developmental trajectory requiring intensive management. A behavioral phenotype of autism may coexist often in children with epilepsy, EEG abnormalities, and regression. Seizures might be difficult to control in these children despite adequate compliance. Studies with larger sample size and longitudinal follow-up will provide better understanding.

The relationship between sleep and behavior in autism spectrum disorder (ASD): a review

Although there is evidence that significant sleep problems are common in children with autism spectrum disorder (ASD) and that poor sleep exacerbates problematic daytime behavior, such relationships have received very little attention in both research and clinical practice. Treatment guidelines to help manage challenging behaviors in ASD fail to mention sleep at all, or they present a very limited account. Moreover, limited attention is given to children with low-functioning autism, those individuals who often experience the most severe sleep disruption and behavioral problems. This paper describes the nature of sleep difficulties in ASD and highlights the complexities of sleep disruption in individuals with low-functioning autism. It is proposed that profiling ASD children based on the nature of their sleep disruption might help to understand symptom and behavioral profiles (or vice versa) and therefore lead to better-targeted interventions. This paper concludes with a discussion of the limitations of current knowledge and proposes areas that are important for future research. Treating disordered sleep in ASD has great potential to improve daytime behavior and family functioning in this vulnerable population.

Incidence and behavioral correlates of epileptiform abnormalities in autism spectrum disorders

Autism spectrum disorders (ASD) are associated with an increased incidence of epilepsy and of epileptiform discharges on electroencephalograms. It is unknown whether epileptiform discharges correlate with symptoms of ASD. We completed a retrospective chart review of 101 patients with ASD who had overnight electroencephalograms. We looked for a relationship between epileptiform abnormalities and diagnosis, history of regression, communication skills, and other features associated with ASD. There was a higher incidence of epileptiform activity in children with stereotypies and aggressive behavior. The incidence of epileptiform abnormalities was significantly lower in Asperger's compared with more severe forms of autism. Results suggest that increasing severity of autistic symptoms may be associated with higher likelihood of epileptiform abnormalities. Whether treatment alters outcome is unknown.

Correlates and risk markers for sleep disturbance in participants of the Autism Treatment Network

We explored possible cognitive, behavioral, emotional, and physiological risk markers for sleep disturbance in children with autism spectrum disorders. Data from 1,583 children in the Autism Treatment Network were analyzed. Approximately 45 potential predictors were analyzed using hierarchical regression modeling. As medication could confound findings, it was included in the analyses as a covariate. Results revealed that anxiety, autism symptom severity, sensory sensitivities, and GI problems were associated with sleep disturbance. IQ positively predicted sleep disturbance, and children with Asperger's Disorder were more vulnerable than others. The amount of variance in sleep outcomes explained by predictor variables was modest (i.e., R (2) from .104 to .201). Predictor variables were evaluated in the context of a bidirectional theoretical framework.

In utero exposure to valproic acid changes sleep in juvenile rats: a model for sleep disturbances in autism

STUDY OBJECTIVES

To determine whether sleep disturbances are found in the valproic acid model of autism spectrum disorders (ASD).

DESIGN

Comparative study for sleep behavior, sleep architecture, electroencephalogram (EEG) spectral analysis, and glutamic acid decarboxylase (GAD) 65/67 protein expression in juvenile rats exposed to valproic acid (VPA), sodium salt, or saline in utero.

SETTING

N/A.

PARTICIPANTS

Juvenile (postnatal day 32) male and female Sprague-Dawley rats.

INTERVENTIONS

In utero exposure to either saline or 400 mg/kg VPA administered intraperitoneally to the dams on gestational day 12.5. On postnatal days 22-24, all rats were implanted with transmitters to record EEG and electromyogram (EMG) activity.

MEASUREMENTS AND RESULTS

During the light phase, when nocturnal animals are typically quiescent, the VPA-exposed animals spent significantly more time in wake (∼35 min) and significantly less time in non-rapid eye movement (NREM) sleep (∼26 min) compared to the saline controls. Furthermore, spectral analysis of the EEG revelled that VPA-exposed animals exhibited increased high-frequency activity during wake and rapid eye movement (REM) sleep and reduced theta power across all vigilance states. Interestingly, the gamma-aminobutyric acid (GABA)-ergic system, which modulates the induction and maintenance of sleep states, was also disrupted, with reduced levels of both GAD 65 and GAD67 in the cortical tissue of VPA-exposed animals compared to saline controls.

CONCLUSIONS

To date, the current animal models of ASD have been underutilized in the investigation of associated sleep disturbances. The VPA animal model recapitulates aspects of sleep disruptions reported clinically, providing a tool to investigate cellular and molecular dysregulation contributing to sleep disruptions in ASD.

The relation between language regression and social communicative development of children with autism spectrum disorder

PURPOSE

To investigate the relationship between language regression and the subsequent social-communicative development of preschool children with Autism Spectrum Disorder (ASD).

METHODS

Thirty children with ASD participated in the study and were divided into two groups: with (n=6) and without (n=24) language regression. Language regression was assessed by the Autism Diagnostic Interview-Revised and the social-communicative development was measured by the Autism Diagnostic Observation Schedule.

RESULTS

Of the 30 children who met the criteria for participation in this study, six (20%) had regression of oral language skills, with a mean age of onset of 25 months. There were no statistical significant differences in the social-communicative development between the groups with and without language regression.

CONCLUSION

The findings of this research do not seem to confirm the relationship between the occurrence of language regression and the subsequent impairment on social-communicative development of children with ASD.

Somatic overgrowth predisposes to seizures in autism spectrum disorders

Background

Comorbidity of Autism Spectrum Disorders with seizures or abnormal EEG (Autism-Epilepsy Phenotype) suggests shared pathomechanisms, and might be a starting point to identify distinct populations within the clinical complexity of the autistic spectrum. In this study, we tried to assess whether distinct subgroups, having distinctive clinical hallmarks, emerge from this comorbid condition.

Methods

Two-hundred and six individuals with idiopathic Autism Spectrum Disorders were subgrouped into three experimental classes depending on the presence of seizures and EEG abnormalities. Neurobehavioral, electroclinical and auxological parameters were investigated to identify differences among groups and features which increase the risk of seizures. Our statistical analyses used ANOVA, post-hoc multiple comparisons, and the Chi-squared test to analyze continuous and categorical variables. A correspondence analysis was also used to decompose significant Chi-squared and reduce variables dimensions.

Results

The high percentage of children with seizures (28.2% of our whole cohort) and EEG abnormalities (64.1%) confirmed that the prevalence of epilepsy in Autism Spectrum Disorders exceeds that of the general population. Seizures were associated with severe intellectual disability, and not with autism severity. Interestingly, tall stature (without macrocephaly) was significantly associated with EEG abnormalities or later onset seizures. However, isolated macrocephaly was equally distributed among groups or associated with early onset seizures when accompanied by tall stature.

Conclusions

Tall stature seems to be a phenotypic “biomarker” of susceptibility to EEG abnormalities or late epilepsy in Autism Spectrum Disorders and, when concurring with macrocephaly, predisposes to early onset seizures. Growth pattern might act as an endophenotypic marker in Autism-Epilepsy comorbidity, delineating distinct pathophysiological subtypes and addressing personalized diagnostic work-up and therapeutic approaches.

Is sleep essential for neural plasticity in humans, and how does it affect motor and cognitive recovery?

There is a general consensus that sleep is strictly linked to memory, learning, and, in general, to the mechanisms of neural plasticity, and that this link may directly affect recovery processes. In fact, a coherent pattern of empirical findings points to beneficial effect of sleep on learning and plastic processes, and changes in synaptic plasticity during wakefulness induce coherent modifications in EEG slow wave cortical topography during subsequent sleep. However, the specific nature of the relation between sleep and synaptic plasticity is not clear yet. We reported findings in line with two models conflicting with respect to the underlying mechanisms, that is, the “synaptic homeostasis hypothesis” and the “consolidation” hypothesis, and some recent results that may reconcile them. Independently from the specific mechanisms involved, sleep loss is associated with detrimental effects on plastic processes at a molecular and electrophysiological level. Finally, we reviewed growing evidence supporting the notion that plasticity-dependent recovery could be improved managing sleep quality, while monitoring EEG during sleep may help to explain how specific rehabilitative paradigms work. We conclude that a better understanding of the sleep-plasticity link could be crucial from a rehabilitative point of view.

Biological and psychological rhythms: an integrative approach to rhythm disturbances in autistic disorder

Biological rhythms are crucial phenomena that are perfect examples of the adaptation of organisms to their environment. A considerable amount of work has described different types of biological rhythms (from circadian to ultradian), individual differences in their patterns and the complexity of their regulation. In particular, the regulation and maturation of the sleep-wake cycle have been thoroughly studied. Its desynchronization, both endogenous and exogenous, is now well understood, as are its consequences for cognitive impairments and health problems. From a completely different perspective, psychoanalysts have shown a growing interest in the rhythms of psychic life. This interest extends beyond the original focus of psychoanalysis on dreams and the sleep-wake cycle, incorporating central theoretical and practical psychoanalytic issues related to the core functioning of the psychic life: the rhythmic structures of drive dynamics, intersubjective developmental processes and psychic containment functions. Psychopathological and biological approaches to the study of infantile autism reveal the importance of specific biological and psychological rhythmic disturbances in this disorder. Considering data and hypotheses from both perspectives, this paper proposes an integrative approach to the study of these rhythmic disturbances and offers an etiopathogenic hypothesis based on this integrative approach.

Exploring the relationship between autism spectrum disorder and epilepsy using latent class cluster analysis

Epilepsy co-occurs frequently in autism spectrum disorders (ASD). Understanding this co-occurrence requires a better understanding of the ASD-epilepsy phenotype (or phenotypes). To address this, we conducted latent class cluster analysis (LCCA) on an ASD dataset (N = 577) which included 64 individuals with epilepsy. We identified a 5-cluster solution with one cluster showing a high rate of epilepsy (29%), earlier age at first recognition, and high rates of repetitive object use and unusual sensory interests. We also conducted LCCA on an ASD-epilepsy subset from the overall dataset (N = 64) which yielded three clusters, the largest of which had impairments in language and motor development; the remaining clusters, while not as developmentally impaired were characterized by different levels of repetitive and sensory behaviors.

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.

Sleep disruption as a correlate to cognitive and adaptive behavior problems in autism spectrum disorders

Sleep problems associated with autism spectrum disorders (ASD) have been well documented, but less is known about the effects of sleep problems on day-time cognitive and adaptive performance in this population. Children diagnosed with autism or pervasive developmental disorder-not otherwise specified (PDD-NOS) (N = 335) from 1 to 10 years of age (M = 5.5 years) were evaluated for the relationships of Behavioral Evaluation of Disorders of Sleep (BEDS; Schreck, 1998) scores to measures of intelligence and adaptive behavior. Results suggested that children who slept fewer hours per night had lower overall intelligence, verbal skills, overall adaptive functioning, daily living skills, socialization skills, and motor development. Children who slept fewer hours at night with waking during the night had more communication problems. Breathing related sleep problems and fewer hours of sleep related most often to problems with perceptual tasks. The results indicate that quality of sleep--especially sleep duration--may be related to problems with day-time cognitive and adaptive functioning in children with autism and PDD-NOS. However, future research must be conducted to further understand these relationships.

Pupil and salivary indicators of autonomic dysfunction in autism spectrum disorder

Dysregulated tonic pupil size has been reported in autism spectrum disorder (ASD). Among the possible sources of this dysregulation are disruptions in the feedback loop between norepinephrine (NE) and hypothalamic systems. In the current study, we examined afternoon levels of salivary alpha-amylase (sAA, a putative correlate of NE) and cortisol (used to assess stress-based responses) in two independent samples of children with ASD. We found a larger pupil size and lower sAA levels in ASD, compared to typical and clinical age-matched controls. This was substantiated at the individual level, as sAA levels were strongly correlated with tonic pupil size. Relatively little diurnal variation in sAA taken in the home environment in the ASD group was also observed, while typical controls showed a significant linear increase throughout the day. Results are discussed in terms of potential early biomarkers and the elucidation of underlying neural dysfunction in ASD.

Neurobiological basis of autism

Autism (autism spectrum disorders) is a complex, strongly genetically influenced, behaviorally defined disorder of the immature brain associated with very uneven intellectual abilities. Among its most salient and potentially treatable neurologic features that this article focuses on are epilepsy, disorganized sleep patterns, and sensory and motor deficits. Its many causes and wide range of severity means that there is no symptom, no pathology, imaging, electroencephalography, or other biologic feature, and no biologic treatment that is universal or diagnostic of this developmental syndrome.

The phenomenology of autistic regression: subtypes and associated factors

This study aimed to investigate the association of autistic regression (AR) and subtypes of AR with medical, developmental and psychiatric factors. Fifty-seven children with autistic spectrum disorders (ASD) were included in the study. Two types of AR are defined as regression after a normal social/language development (type 1) and regression as the worsening of previously reported autistic features (type 2). The frequency of history of AR was 56.1%. Male gender and sleep problems were found to be associated with a positive history of AR. The frequency of gastrointestinal complaints/diseases was higher in children with regression type 2 when compared to the children with regression type 1. Future studies with larger sample size and prospective design will contribute to clarifying the phenomenology and the associated factors of AR.

Sleep, anxiety and challenging behaviour in children with intellectual disability and/or autism spectrum disorder

Children with an intellectual disability (ID) and/or autism spectrum disorder (ASD) are known to suffer from significantly more sleep problems, anxiety and challenging behaviour (CB) than typically developing children (TD), yet little is known about the relationship between these factors in the child ID/ASD population. The study aim was to examine these relationships. We hypothesised that there would be significant positive correlations between the three factors and that sleep problems and anxiety would predict a significant amount of the variance in levels of CB. Parental measures of sleep problems, anxiety and CB were completed by 187 parents of children with ID and/or ASD. Significant positive associations were found between the three factors. A hierarchical multiple regression showed that medication, sleep problems and anxiety accounted for 42% of the variance in CB, with a large effect size. These findings suggest that these relationships should be considered during clinical practice, particularly in the case of CB interventions where sleep problems and/or anxiety are also present.

Sleep correlates of pervasive developmental disorders: a review of the literature

Sleep disturbance is a significant problem in the general pediatric population, and it occurs even more frequently in children with pervasive developmental disorders (PDDs). Much time and energy have been spent examining the characteristics that predispose children to insomnia and it is likely that equivalent factors influence sleep in PDDs. Though similarly affected, it is the unique set of characteristics incumbent in a diagnosis of PDD that has additive effects and increases the likelihood for developing other predisposing factors and subsequent sleep loss. This review summarized research that has explored the behavioral, cognitive, and emotional correlates of sleep disturbance in children with PDDs. The literature provided 38 sleep studies that used either subjective or objective sleep measures. Of these, 17 met criteria for inclusion. Studies were evaluated for their attempts at matching their study samples and adjusting for possible confounding variables. The results revealed that the combined effects of autism symptom severity, internalizing behavior, and externalizing behavior, were the main predisposing factors for the development of insomnia. Other factors included medical conditions, epilepsy, and medication use (likely a proxy for behavior difficulty and even sleep disorder). A bidirectional theoretical framework for sleep disturbance in children with PDDs has been posited as a conceptual guide for future study. Recommendations for future study designs are included.

Association between fatigue and autistic symptoms in children with cri du chat syndrome

In the current study, the authors examined whether the fatigue level of children diagnosed with cri du chat syndrome was associated with the expression of autistic symptoms. Sixty-nine children with cri du chat syndrome were compared with 47 children with moderate to severe intellectual disabilities who did not differ on intellectual severity. Participants were assessed using the Infant Sleep Questionnaire ( J. M. B. Morrell, 1999 ) for fatigue-level rating and the Childhood Autism Rating Scale ( E. Schopler, R. J. Reichler, & B. R. Renner, 1988 ) for autism-level rating. In support of the authors' hypothesis, results indicated that children who exhibited high levels of fatigue were more likely to express high levels of autistic symptoms. Contrary to the authors' hypothesis, children in the comparison group who exhibited high levels of fatigue conferred the greatest vulnerability to the expression of autistic symptoms.

The neurology of autism spectrum disorders

PURPOSE OF REVIEW

Neurological comorbidities in autism spectrum disorders (ASDs) are not only common, but they are also associated with more clinical severity. This review highlights the most recent literature on three of autism's most prevalent neurological comorbidities: motor impairment, sleep disorders and epilepsy.

RECENT FINDINGS

Motor impairment in ASDs manifests as both delays and deficits, with delays found in gross and fine motor domains and deficits found in praxis, coordination and gait, all of which affect other cognitive and behavioral domains. Sleep disorders, especially insomnia, occur in up to 83% of children with ASDs and recent studies have begun to explore the underlying biochemical and behavioral basis of the impairment, which has bolstered treatment studies. Epilepsy is reported in up to one third of children with ASDs, and new studies have focused on identifying the genetic causes of this association.

SUMMARY

Better characterization of the phenotype, developmental trajectory and underlying pathophysiology of these neurological comorbidities will enable us to define neurological endophenotypes within the autism spectrum. Future studies must investigate the emergence of these comorbidities prospectively in order to determine whether they lie on the causal pathway to ASDs or whether they reflect epiphenomena of the disorder. As epilepsy and sleep disorders can be treated and may contribute significantly to behavioral and cognitive abnormalities in ASDs, their identification is of high clinical relevance.

Autism spectrum disorders and epilepsy: moving towards a comprehensive approach to treatment

The biological and phenotypic heterogeneity of children with autism spectrum disorders (ASD) and epilepsy presents a significant challenge to the development of effective treatment protocols. There is no single treatment or treatment protocol for children with ASD or epilepsy. Children with co-occurring ASD and epilepsy should undergo a comprehensive assessment that includes investigation of underlying biological etiologies as well assessment of cognitive, language, affective, social and behavioral function prior to initiating treatment. The comprehensive treatment of children with ASD is based on a combination of therapeutic psychosocial interventions in combination with pharmacological agents. A process-oriented approach to assessment and intervention allows careful analysis of the child's response to treatment such that treatment protocols may be revised secondary to any changes in developmental trajectory of the child with ASD and epilepsy. The possibility of developing pharmacological interventions that target both ASD and epilepsy awaits definitive evidence. The best hope for good developmental outcomes in children with ASD and epilepsy is early recognition and comprehensive treatment of both the ASD and epilepsy.

Autism and epilepsy: historical perspective

Autism spectrum disorders (ASD) and epilepsy co-occur in approximately 30% of individuals with either ASD or epilepsy. While there is no single unifying ASD-epilepsy phenotype, understanding potential commonalities in subgroups of children with an ASD-epilepsy phenotype will help us disentangle the pathophysiology of both ASD and epilepsy. Throughout this brief historical perspective we selectively review critical trends in ASD-epilepsy research and highlight challenges to clinical and research efforts including terminology, heterogeneity of both ASD and epilepsy, and lack of careful characterization of children affected with both ASD and epilepsy. These complex issues continue to burden research on the diagnosis, neurobiology and management of children with ASD and epilepsy. A key concept that has emerged during the past 40 years is the strong association between intellectual disability and a higher prevalence of epilepsy in individuals with ASD. In addition, the two peaks of seizure onset, one in early childhood and one in adolescence and continuing through adulthood may be unique to individuals with ASD. The overlap of language and autistic regression to epilepsy, EEG epileptiform activity, sleep, and to epileptic encephalopathies such as Landau-Kleffner syndrome continue to be controversial areas of research and of clinical interest. An emerging consensus is that shared developmental genetic, molecular and pathophysiological mechanisms exist and account for the common co-occurrence of ASD and epilepsy.

Sleep in children with autism with and without autistic regression

The purpose of the present investigation was to characterize and compare traditional sleep architecture and non-rapid eye movement (NREM) sleep microstructure in a well-defined cohort of children with regressive and non-regressive autism, and in typically developing children (TD). We hypothesized that children with regressive autism would demonstrate a greater degree of sleep disruption either at a macrostructural or microstructural level and a more problematic sleep as reported by parents. Twenty-two children with non-regressive autism, 18 with regressive autism without comorbid pathologies and 12 with TD, aged 5-10years, underwent standard overnight multi-channel polysomnographic evaluation. Parents completed a structured questionnaire (Childrens' Sleep Habits Questionnaire-CSHQ). The initial hypothesis, that regressed children have more disrupted sleep, was supported by our findings that they scored significantly higher on CSHQ, particularly on bedtime resistance, sleep onset delay, sleep duration and night wakings CSHQ subdomains than non-regressed peers, and both scored more than typically developing controls. Regressive subjects had significantly less efficient sleep, less total sleep time, prolonged sleep latency, prolonged REM latency and more time awake after sleep onset than non-regressive children and the TD group. Regressive children showed lower cyclic alternating pattern (CAP) rates and A1 index in light sleep than non-regressive and TD children. Our findings suggest that, even though no particular differences in sleep architecture were found between the two groups of children with autism, those who experienced regression showed more sleep disorders and a disruption of sleep either from a macro- or from a microstructural viewpoint.

Sleep in children with autistic spectrum disorder

Children and adolescents with autistic spectrum disorders (ASD) suffer from sleep problems, particularly insomnia, at a higher rate than typically developing children, ranging from 40% to 80%. Sleep problems in ASD might occur as a result of complex interactions between biological, psychological, social/environmental, and family factors, including child rearing practices that are not conducive to good sleep. Interestingly, children with a history of developmental regression have a more disturbed sleep pattern than children without regression. Even though regulation of sleep in children with ASD is still poorly understood, circadian abnormalities in autism might be the result of genetic abnormalities related to melatonin synthesis and melatonin's role in modulating synaptic transmission. Recently a bifurcation of the sleep/wake cycle with increased sensitivity to external noise and short sleep duration causing irregular sleep onset and wake up times has been suggested. Identifying and treating sleep disorders may result not only in improved sleep, but also impact favorably on daytime behavior and family functioning. Several studies have also demonstrated effectiveness of behavioral interventions for sleep onset and maintenance problems in these populations. When behavioral interventions are not effective or lead only to a partial response, pharmacological treatment options should be considered. Studies of melatonin use in children with ASD provide evidence for its effectiveness and safety in the long run. The clinician assessing a child with an ASD should screen carefully for sleep disorders and make referrals as indicated.

Medical treatment of autism spectrum disorders

PURPOSE OF REVIEW

There are several common medical conditions occurring in people with autism spectrum disorders (ASD) that can benefit from treatment and can in turn improve the health and quality of life of people with ASD. This review will primarily focus on these medical comorbidities, with a brief review of potential future treatments.

RECENT FINDINGS

There continues to be disagreement regarding the exact prevalence and etiological significance of gastrointestinal conditions, epilepsy and other abnormal electroencephalographic findings, and sleep problems. It is not clear whether gastrointestinal conditions occur more frequently than in typically developing children, and whether there are distinct conditions that occur more often in ASD than in non-ASD populations. Abnormal electroencephalographic findings have been reported in up to 60% of children with ASD, and some believe that these abnormalities may be responsible for parts of the ASD phenotype. Sleep problems are reported more frequently than in the general population, and effective treatments are available. Future medical treatments for ASD may be directed at underlying core symptoms and have greater impact than today's symptomatic approach.

SUMMARY

Further research in these areas is needed to better guide diagnosis and treatment of a variety of medical conditions experienced by people with ASD.

Epidemiology and management of insomnia in children with autistic spectrum disorders

Insomnia is the predominant sleep concern in children with autistic spectrum disorder (ASD), and its nature is most likely multifactorial, with neurochemical (abnormalities in serotonergic transmission or melatonin levels), psychiatric (anxiety), and behavioral (poor sleep habits) etiological factors involved. Children with ASD experience sleep problems similar to those of typically developing children, although the prevalence is markedly higher, occurring in 44-83% of school-aged children with ASD. Caregivers usually report that insomnia is the most frequent sleep disorder, described as disorders of initiating and maintaining sleep, restless sleep, bedtime resistance, co-sleeping, alterations of sleep hygiene, and early awakenings in the morning. Many actigraphic studies have added information on sleep disorders, confirming the questionnaire findings in the majority of cases. There are relatively few polysomnographic data for ASD, compared with questionnaire studies, and most of these studies reported a reduction in total sleep time and more undifferentiated sleep in the youngest patients. These findings were associated with several sleep microstructure alterations during rapid eye movement (REM) sleep, and with non-REM (NREM) sleep microstructure changes that appeared to be related to cognitive impairment rather than to the autistic core. Moreover, few data about other less frequent sleep disorders, such as periodic limb movements disorder and obstructive sleep apnea syndrome, bruxism, and the influence of epilepsy and EEG abnormalities, are available. Both pharmacologic and behavioral interventions have been suggested for the treatment of sleep problems in autistic children. The most common types of behavioral interventions are complete extinction (removing reinforcement to reduce a behavior) and various forms of graduated extinction. Melatonin has shown promising results in the treatment of insomnia in children with ASD. Although controlled studies are limited, there are more data demonstrating the safety and effectiveness of melatonin in ASD than for other sedative/hypnotic drugs. Finally, a dual treatment for insomnia in ASDs with melatonin and behavioral techniques has been suggested. A recent study using a combination of genetic and functional experimental techniques reported evidence that low melatonin concentration caused by a primary deficit in acetylserotonin methyltransferase activity is a risk factor for ASD. Sleep problems usually start at the same age as developmental regression, suggesting a higher vulnerability at this period of life. Further studies, beginning at younger ages, are necessary to better investigate these aspects and the role of melatonin in insomnia in children with ASD.

Update on autism: a review of 1300 reports published in 2008

This publication, by reviewing 1300 studies published on autism in 2008, represents an update on this topic. Results include possible parental influences, maternal conditions, and studies on genes and chromosomes. Possible etiological factors involve the "extreme male brain," defects in the mirror neuron system, vaccines, underconnectivity, disorders of central coherence, and many other more specific etiologies. Assessments or tests for autism are also reviewed. Characteristics of autistic individuals include repetitive behavior, language disorders, sleep disturbances, social problems, joint attention disorders, seizures, allergic reactions, and various behavioral changes. Cognitive changes involve IQ, reasoning, and verbal and language disorders. The savant syndrome is a fascinating phenomenon, at times seen in autistic individuals. Neurophysiological and neuroanatomical changes are also reviewed, as are comorbid conditions. Finally, treatment involves various medications including risperidone, ziprasidone, and antipsychotic drugs, as well as different procedures such as magnetic stimulation, acupuncture, and hyperbaric oxygen therapy. As mentioned in the 2007 survey, nearly every conceivable problem that a child can have may be found in these unfortunate children and nearly every conceivable etiology has been mentioned to account for this serious disorder.

Sleep patterns in autism spectrum disorders

Like children with other developmental disabilities, children with autism spectrum disorders suffer from sleep problems at a greater rate than typically developing children. It is increasingly recognized that addressing these sleep problems may improve daytime functioning and decrease family stress. The sleep problems experienced by children with autism spectrum disorders are presented in this article.

CSWS-related autistic regression versus autistic regression without CSWS

Continuous spike-waves during slow-wave sleep (CSWS) and Landau-Kleffner syndrome (LKS) are two clinical epileptic syndromes that are associated with the electroencephalography (EEG) pattern of electrical status epilepticus during slow wave sleep (ESES). Autistic regression occurs in approximately 30% of children with autism and is associated with an epileptiform EEG in approximately 20%. The behavioral phenotypes of CSWS, LKS, and autistic regression overlap. However, the differences in age of regression, degree and type of regression, and frequency of epilepsy and EEG abnormalities suggest that these are distinct phenotypes. CSWS with autistic regression is rare, as is autistic regression associated with ESES. The pathophysiology and as such the treatment implications for children with CSWS and autistic regression are distinct from those with autistic regression without CSWS.

Six-month persistence of sleep problems in young children with autism, developmental delay, and typical development

OBJECTIVE

This study examined the persistence of sleep problems in preschool children with autism and two matched comparison groups: children with developmental delay without autism and typically developing children. Sleep problems were defined subjectively by parent report, by the Children's Sleep Habits Questionnaire (CSHQ), and objectively by quantitative Research Diagnostic Criteria (RDC) derived from actigraphic recordings.

METHOD

Children were studied on three occasions, each separated by a 3-month interval. At each assessment, the children were recorded actigraphically for 1 week, and parents completed sleep-wake diaries and the CSHQ. Descriptive statistics and odds ratios were used to assess the occurrence and stability of sleep problems within children and across groups and to explore how actigraph- and CSHQ-defined sleep problems affect parental sleep problem reports.

RESULTS

Parent reports of a generic sleep problem were more prevalent than RDC- and CSHQ-defined sleep problems, especially for children with neurodevelopmental disorders. For all groups, objectively measured sleep problems were rarely persistent during the 6-month period. The children in both neurodevelopmental groups, however, had more sleep problems on one or two occasions, using actigraph and the CSHQ, than typically developing children.

CONCLUSIONS

Objective and subjective measures of sleep problems in preschool-aged children produce different results. In a community sample, the rate of actigraph- and CSHQ-defined sleep problems in children with autism did not differ from rates for typically developing children, although the parent report of a generic sleep problem was significantly greater.

The role of epilepsy and epileptiform EEGs in autism spectrum disorders

Autism is a neurodevelopmental disorder of unknown etiology characterized by social and communication deficits and the presence of restricted interests/repetitive behaviors. Higher rates of epilepsy have long been reported, but prevalence estimates vary from as little as 5% to as much as 46%. This variation is probably the result of sample characteristics that increase epilepsy risk such as sample ascertainment, lower intelligence quotient (IQ), the inclusion of patients with nonidiopathic autism, age, and gender. However, critical review of the literature reveals that the rate in idiopathic cases with normal IQ is still significantly above the population risk suggesting that autism itself is associated with an increased risk of epilepsy. Recently, there has been interest in the occurrence of epileptiform electroencephalograms (EEGs) even in the absence of epilepsy. Rates as high as 60% have been reported and some investigators propose that these abnormalities may play a causal role in the autism phenotype. Although this phenomenon is still not well understood and risk factors have yet to be determined, the treatment implications are increasingly important. We review the recent literature to elucidate possible risk factors for both epilepsy and epileptiform EEGs. We then review existing data and discuss controversies surrounding treatment of EEG abnormalities.