Psychopharmacology in autism: an update

Probing heterogeneity to identify individualized treatment approaches in autism: Specific clusters of executive function challenges link to distinct co-occurring mental health problems

LAY ABSTRACT

Many autistic people struggle with mental health problems like anxiety, depression, inattention, and aggression, which can be challenging to treat. Executive function challenges, which impact many autistic individuals, may serve as a risk factor for mental health problems or make treating mental health conditions more difficult. While some people respond well to medication or therapy, others do not. This study tried to understand if there are different subgroups of autistic young people who may have similar patterns of executive function strengths and challenges-like flexibility, planning, self-monitoring, and emotion regulation. Then, we investigated whether executive function subgroups were related to mental health problems in autistic youth. We found three different types of executive function subgroups in autistic youth, each with different patterns of mental health problems. This helps us identify specific profiles of executive function strengths and challenges that may be helpful with identifying personalized supports, services, and treatment strategies for mental health conditions.

Pharmacophore modeling, molecular docking, and molecular dynamics studies to identify new 5-HT2AR antagonists with the potential for design of new atypical antipsychotics

Some important atypical antipsychotic drugs target the serotonergic receptor 2A (5-HT2AR). Currently, new therapeutic strategies are needed to offer faster onset of action with fewer side effects and, therefore, greater efficacy in a substantial proportion of patients with neuropsychological disorders such as Autism and Parkinson. The main objective of this work was to use SBDD methods to identify new hit compounds potentially useful as precursors of novel and selective 5-HT2AR antagonists. A structure-based pharmacophore screening study based on a selective antagonist was carried out in ten databases. The set obtained was refined using molecular docking, and the five most promising compounds were subjected to molecular dynamics simulations. The most stable and promising hit occupied a side pocket present in the 5-HT2AR, a site that can be explored to obtain selective ligands. Simulations against 5-HT2CR and D2R showed that the best hit could not form stable complexes with these targets, strengthening the hypothesis that the hit presents selective binding by the receptor of interest. The selected hits showed some predicted toxicity risk or violated some drug-likeness property. However, it can be concluded that the identified hits are the most promising for performing in vitro assays. Once the presence of activity is confirmed, they could become precursors of optimized and selective antagonists of 5-HT2AR. An SBDD study was carried out to identify new selective 5-HT2AR ligands potentially useful for designing selective atypical antipsychotics.

Reading ebooks and printed books with parents: A case study of children with autism spectrum disorders

Background and aims

Ebooks have become a ubiquitous presence in many classrooms today. Yet, empirical evidence on literacy development has not been well produced, especially for children with autism spectrum disorder (ASD). This mixed-method case study aimed to explore how four children with ASD interact with ebooks and printed books with parents at home.

Methods

Four children (age 5-7 years) with ASD and their parents read one animated ebook and another printed book over four separate sessions. Parents also explained preselected word meanings to their children. In this mixed-method case study, we examined multiple quantitative and qualitative sources of evidence related to reading with parents at home.

Results

Quantitatively, all four children with ASD learned more word meanings from ebook than from the printed book, and three demonstrated a higher engagement with ebook than the printed book reading. Qualitatively, the majority of parents felt their children's engagement was higher with ebook than with printed book. Children with ASD tend to have tactile-related experiences while reading the printed book and auditory-related experiences during the ebook reading. Qualitative data also demonstrated a particular feature reported to be beneficial in previous research could be distracting for some children with ASD.

Implications

When parents are trained to explain critical word meanings to their children, animated ebooks can effectively improve the meaning-making skills of children with ASD. Findings also highlight the importance of individualized attention when choosing and using ebooks for children with ASD.

Important Preliminary Insights for Designing Successful Communication between a Robotic Learning Assistant and Children with Autism Spectrum Disorder in Germany

Early therapeutic intervention programs help children diagnosed with Autism Spectrum Disorder (ASD) to improve their socio-emotional and functional skills. To relieve the children’s caregivers while ensuring that the children are adequately supported in their training exercises, new technologies may offer suitable solutions. This study investigates the potential of a robotic learning assistant which is planned to monitor the children’s state of engagement and to intervene with appropriate motivational nudges when necessary. To analyze stakeholder requirements, interviews with parents as well as therapists of children with ASD were conducted. Besides a general positive attitude towards the usage of new technologies, we received some important insights for the design of the robot and its interaction with the children. One strongly accentuated aspect was the robot’s adequate and context-specific communication behavior, which we plan to address via an AI-based engagement detection system. Further aspects comprise for instance customizability, adaptability, and variability of the robot’s behavior, which should further be not too distracting while still being highly predictable.

Improvement of the Clinical and Psychological Profile of Patients with Autism after Methylcobalamin Syrup Administration

(1) Background: Autism, also known as autism-spectrum disorder, is a pervasive developmental disorder affecting social skills and psychological status in particular. The complex etiopathogenesis of autism limits efficient therapy, which leads to problems with the normal social integration of the individual and causes severe family distress. Injectable methylcobalamin was shown to improve the clinical status of patients via enhanced cell oxidative status and/or methylation capacity. Here we tested the efficiency of a syrup form of methylcobalamin in treating autism. (2) Methods: Methylcobalamin was administered daily at 500 µg dose to autistic children and young adults (n = 25) during a 200-day period. Clinical and psychological status was evaluated by parents and psychologists and plasma levels of reduced and oxidized glutathione, vitamin B12, homocysteine, and cysteine were determined before the treatment, and at day 100 and day 200 of the treatment. (3) Results: Good patient compliance was reported. Methylcobalamin treatment gradually improved the overall clinical and psychological status, with the highest impact in the social domain, followed by the cognitive, behavioral and communication characteristics. Changes in the clinical and psychological status were strongly associated with the changes in the level of reduced glutathione and reduced/oxidized glutathione ratio. (4) Conclusion: A high dose of methylcobalamin administered in syrup form ameliorates the clinical and psychological status of autistic individuals, probably due to the improved oxidative status.

Practitioner's review: medication for children and adolescents with autism spectrum disorder (ASD) and comorbid conditions

Alleviating the multiple problems of children with autism spectrum disorder (ASD) and its comorbid conditions presents major challenges for the affected children, parents, and therapists. Because of a complex psychopathology, structured therapy and parent training are not always sufficient, especially for those patients with intellectual disability (ID) and multiple comorbidities. Moreover, structured therapy is not available for a large number of patients, and pharmacological support is often needed, especially in those children with additional attention deficit/hyperactivity and oppositional defiant, conduct, and sleep disorders.

Dopamine in Autism Spectrum Disorders-Focus on D2/D3 Partial Agonists and Their Possible Use in Treatment

Autism spectrum disorders (ASD) are a group of disorders characterized by impairment in social communication and repetitive and stereotyped behaviors. ASD etiology is very complex, including the effect of both genetic and environmental factors. So far, no specific treatment for the core symptoms of ASD has been developed, although attempts have been made for the treatment of repetitive behavior. The pharmacological treatment is aimed at treating non-specific symptoms such as irritability and aggression. Recent studies pointed out to the possible role of altered dopamine signaling in mesocorticolimbic and nigrostriatal circuits in ASD. In addition, several research pointed out to the association of dopamine receptors polymorphism and ASD, specifically repetitive and stereotyped behavior. In this paper, we will provide a review of the studies regarding dopamine signaling in ASD, existing data on the effects of D2/D3 partial agonists in ASD, possible implications regarding their individual receptor profiles, and future perspectives of their possible use in ASD treatment.

From Toddlerhood to Adolescence: Which Characteristics Among Toddlers with Autism Spectrum Disorder Predict Adolescent Attention Deficit/Hyperactivity Symptom Severity? A Long-Term Follow-Up Study

High rates of attention deficit/hyperactivity disorder (ADHD) comorbidity have been described in autism spectrum disorder (ASD). This study searched for predictors at toddlerhood of the severity of ADHD symptoms at adolescence. The study included 65 participants, (mean age = 13:8 year), diagnosed with ASD at toddlerhood. Participants underwent a comprehensive assessment of cognitive ability, adaptive skills and autism severity at toddlerhood and adolescence. More severe restricted and repetitive behaviors (RRB) in toddlerhood predicted the severity of Inattention symptoms. In addition, more severe RRB and lower adaptive skills in the toddler years significantly predicted the severity of Hyperactivity/Impulsivity symptoms. Adolescents with elevated ADHD symptoms diagnosed at toddlerhood with ASD showed lower cognitive and adaptive skills and more severe autism symptoms.

The effect of stimulants on irritability in autism comorbid with ADHD: a systematic review

Introduction: While there is a very high rate of comorbidity of autism and ADHD, there are controversies about prescribing stimulants in children with autism. This is a systematic review about the effect of stimulants on irritability in children with both autism and ADHD. Methods: A systematic review was conducted to study the possible effect of stimulants on irritability in autism and ADHD using the databases of PubMed, Scopus, EMBASE, and ScienceDirect in September 2018. Eligible clinical trials of stimulants in the treatment of Autism and ADHD without restriction of language were included. The primary outcome was irritability score. The full texts of relevant articles were studied, and their references were scanned for any possible related article. Results: Out of 1,315 citations, there were 26 relevant articles. Of the relevant articles, 16 were not interventional studies and were excluded. There were 10 interventional studies. None of them considered irritability as a main outcome. Also, none of them studied the effect of stimulants on irritability in autism plus ADHD. Current uncontrolled evidence about the association of stimulants with irritability is controversial. Conclusion: The current evidence is not enough to support or discourage the effect of stimulants on irritability in children and adolescents with both autism and ADHD. Well-designed controlled clinical trials need to be conducted for this ignored research area.

Problem behaviours and Major Depressive Disorder in adults with intellectual disability and autism

The high prevalence of Problem Behaviours (PB) in persons with intellectual disability (ID) and Autism Spectrum Disorder (ASD) has been associated by some researchers to a proportionate frequency of Major Depressive Disorder (MDD), which have a different presentation in persons with ID and ASD than in the general population, mostly as behavioural changes. Nevertheless, evidence on this behavioural equivalency is still scarce. The present study aims at evaluating the rate of MDD in persons with ID and ASD presenting PB. Two groups of persons with mild-to-moderate ID and ASD, with and without PB underwent a complex clinical (Diagnostic Manual - Intellectual Disability) and instrumental (Reiss Screen for Maladaptive Behaviour; Mini Psychiatric Assessment Schedule for Adults with Developmental Disabilities). The prevalence of MDD was found to be significantly higher in the group with PB. The severity of depressive symptoms resulted to have a strong correlation with the scores of instrumental assessment of PB. Our findings support previous literature on a high association between PB and MDD in persons with ID and ASD. The level of the equivalency between specific MDD symptoms and different PB deserves further investigations.

Propranolol for treating emotional, behavioural, autonomic dysregulation in children and adolescents with autism spectrum disorders

OBJECTIVES

To date, there is no single medication prescribed to alleviate all the core symptoms of Autism Spectrum Disorder (ASD; National Institute of Health and Care Excellence, 2016). Both serotonin reuptake inhibitors and drugs for psychosis possess therapeutic drawbacks when managing anxiety and aggression in ASD. This review sought to appraise the use of propranolol as a pharmacological alternative when managing emotional, behavioural and autonomic dysregulation (EBAD) and other symptoms.

MATERIALS AND METHODS

Sixteen reports examined the administration of propranolol in the context of ASD.

RESULTS

Sixteen reports broadly covered cognitive domains, neural correlates, and behavioural domains. From the eight single-dose clinical trials, propranolol led to significant improvements in cognitive performance - verbal problem solving, social skills, mouth fixation, and conversation reciprocity; and changes in neural correlates - improvement in semantic networks and functional connectivity. The remaining eight case series and single case reports showed improvements in EBAD, anxiety, aggressive, self-injurious and hypersexual behaviours. Additionally, propranolol significantly improved similar behavioural domains (aggression and self-injury) for those with acquired brain injury.

CONCLUSION

This review indicates that propranolol holds promise for EBAD and cognitive performance in ASD. Given the lack of good quality clinical trials, randomised controlled trials are warranted to explore the efficacy of propranolol in managing EBAD in ASD.

Impact of CYP2D6 Polymorphism on Steady-State Plasma Levels of Risperidone and 9-Hydroxyrisperidone in Thai Children and Adolescents with Autism Spectrum Disorder

OBJECTIVE

The purpose of this study was to investigate the influence of CYP2D6 gene polymorphisms on plasma concentrations of risperidone and its metabolite in Thai children and adolescents with autism spectrum disorder (ASD).

METHODS

All 97 autism spectrum disorder patients included in this study had been receiving risperidone at least for 1 month. The CYP2D6 genotypes were determined by real-time polymerase chain reaction (PCR)-based allelic discrimination for CYP2D6*4, *10, and *41 alleles. Plasma concentrations of risperidone and 9-hydroxyrisperidone were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

Among the 97 patients, the most important nonfunctional alleles (CYP2D6*4 and *5) were detected, whereas the most common allele was CYP2D6*10 (55.9%). CYP2D6 genotyping revealed 90 (92.78%) patients to be extensive metabolizers (EM) and 7 (7.22%) to be intermediate metabolizers (IM). Plasma levels of risperidone were significantly higher in individuals with CYP2D6*5/*10 (p = 0.02), CYP2D6*10/*10 (p = 0.04), and CYP2D6*10/*41 (p = 0.04). Additionally, the plasma concentration of risperidone/9-OH risperidone ratio in patients with a CYP2D6 activity score of 0.5 were significantly higher than those with a CYP2D6 activity score of 2 (p = 0.04). Conversely, no significant influence was found among CYP2D6 polymorphisms, plasma concentrations of 9-hydroxyrisperidone, and the total active moiety.

CONCLUSIONS

This is the first study to investigate the effects of CYP2D6 genetic polymorphisms on the plasma concentrations of risperidone in Thai children with ASD. The findings indicate that CYP2D6 polymorphisms affect the plasma concentrations of risperidone and the risperidone/9-hydroxyrisperidone ratio. Genetic screening for CYP2D6 polymorphisms could help to predict unexpected adverse events caused by the higher plasma concentration of risperidone.

Striatal cholinergic interneurons and D2 receptor-expressing GABAergic medium spiny neurons regulate tardive dyskinesia

Tardive dyskinesia (TD) is a drug-induced movement disorder that arises with antipsychotics. These drugs are the mainstay of treatment for schizophrenia and bipolar disorder, and are also prescribed for major depression, autism, attention deficit hyperactivity, obsessive compulsive and post-traumatic stress disorder. There is thus a need for therapies to reduce TD. The present studies and our previous work show that nicotine administration decreases haloperidol-induced vacuous chewing movements (VCMs) in rodent TD models, suggesting a role for the nicotinic cholinergic system. Extensive studies also show that D2 dopamine receptors are critical to TD. However, the precise involvement of striatal cholinergic interneurons and D2 medium spiny neurons (MSNs) in TD is uncertain. To elucidate their role, we used optogenetics with a focus on the striatum because of its close links to TD. Optical stimulation of striatal cholinergic interneurons using cholineacetyltransferase (ChAT)-Cre mice expressing channelrhodopsin2-eYFP decreased haloperidol-induced VCMs (~50%), with no effect in control-eYFP mice. Activation of striatal D2 MSNs using Adora2a-Cre mice expressing channelrhodopsin2-eYFP also diminished antipsychotic-induced VCMs, with no change in control-eYFP mice. In both ChAT-Cre and Adora2a-Cre mice, stimulation or mecamylamine alone similarly decreased VCMs with no further decline with combined treatment, suggesting nAChRs are involved. Striatal D2 MSN activation in haloperidol-treated Adora2a-Cre mice increased c-Fos⁺ D2 MSNs and decreased c-Fos⁺ non-D2 MSNs, suggesting a role for c-Fos. These studies provide the first evidence that optogenetic stimulation of striatal cholinergic interneurons and GABAergic MSNs modulates VCMs, and thus possibly TD. Moreover, they suggest nicotinic receptor drugs may reduce antipsychotic-induced TD.

Using venlafaxine to treat behavioral disorders in patients with autism spectrum disorder

OBJECTIVE

To test the efficacy of venlafaxine at a dose of 18.75 mg/day on the reduction of behavioral problems such as irritability and hyperactivity/noncompliance in patients with intellectual disabilities and autism spectrum disorder (ASD). Our secondary hypothesis was that the usual doses of zuclopenthixol and/or clonazepam would decrease in the venlafaxine-treated group.

METHODS

In a randomized double-blind study, we compared six patients who received venlafaxine along with their usual treatment (zuclopenthixol and/or clonazepam) with seven patients who received placebo plus usual care. Irritability, hyperactivity/noncompliance, and overall clinical improvement were measured after 2 and 8 weeks, using validated clinical scales.

RESULTS

Univariate analyses showed that the symptom of irritability improved in the entire sample (p = 0.023 after 2 weeks, p = 0.061 at study endpoint), although no difference was observed between the venlafaxine and placebo groups. No significant decrease in hyperactivity/noncompliance was observed during the study. At the end of the study, global improvement was observed in 33% of participants treated with venlafaxine and in 71% of participants in the placebo group (p = 0.29). The study found that decreased cumulative doses of clonazepam and zuclopenthixol were required for the venlafaxine group. Multivariate analyses (principal component analyses) with at least three combinations of variables showed that the two populations could be clearly separated (p b 0.05). Moreover, in all cases, the venlafaxine population had lower values for the Aberrant Behavior Checklist (ABC), Behavior Problems Inventory (BPI), and levels of urea with respect to the placebo group. In one case, a reduction in the dosage of clonazepam was also suggested. For an additional set of variables (ABC factor 2, BPI frequency of aggressive behaviors, hematic ammonia at Day 28, and zuclopenthixol and clonazepam intake), the separation between the two samples was statistically significant as was the Bartlett's test, but the Kaiser–Meyer–Olkin Measure of Sampling Adequacy was below the accepted threshold. This set of variables showed a reduction in the cumulative intake of both zuclopenthixol and clonazepam.

CONCLUSION

Despite the small sample sizes, this study documented a statistically significant effect of venlafaxine. Moreover, we showed that lower doses of zuclopenthixol and clonazepam were needed in the venlafaxine group, although this difference was not statistically significant. This was confirmed by multivariate analyses, where this difference reached statistical significance when using a combination of variables involving zuclopenthixol. Larger-scale studies are recommended to better investigate the effectiveness of venlafaxine treatment in patients with intellectual disabilities and ASD.

Comparative analysis of self-injury in people with psychopathology or neurodevelopmental disorders

Self-injury is a complex and poorly understood behavior observed in people with psychopathology or neurodevelopmental disorders (NDD). Despite the differences in etiology and progression of these distinct disease domains, it is possible that overlapping molecular pathways underlie the expression of self-injurious behaviors (SIBs). This review outlines the similarities and differences at the behavioural and molecular level, where SIBs in both conditions may involve opioid, nucleoside, and dopamine signalling. These points of convergence have important implications for treatment and research of SIB in both populations.

Risperidone and the 5-HT2A receptor antagonist M100907 improve probabilistic reversal learning in BTBR T + tf/J mice

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interactions with restricted interests and repetitive behaviors (RRBs). RRBs can severely limit daily living and be particularly stressful to family members. To date, there are limited options for treating this feature in ASD. Risperidone, an atypical antipsychotic, is approved to treat irritability in ASD, but less is known about whether it is effective in treating "higher order" RRBs, for example cognitive inflexibility. Risperidone also has multiple receptor targets in which only a subset may be procognitive and others induce cognitive impairment. 5HT2A receptor blockade represents one promising and more targeted approach, as various preclinical studies have shown that 5HT2A receptor antagonists improve cognition. The present study investigated whether risperidone and/or M100907, a 5HT2A receptor antagonist, improved probabilistic reversal learning performance in the BTBR T + tf/J (BTBR) mouse model of autism. The effects of these treatments were also investigated in C57BL/6J (B6) mice as a comparison strain. Using a spatial reversal learning test with 80/20 probabilistic feedback, similar to one in which ASD individuals exhibit impairments, both risperidone (0.125 mg) and M100907 (0.01 and 0.1 mg) improved reversal learning in BTBR mice. Risperidone (0.125 mg) impaired reversal learning in B6 mice. Improvement in probabilistic reversal learning performance resulted from treatments enhancing the maintenance of the newly correct choice pattern. Because risperidone can lead to unwanted side effects, treatment with a specific 5HT2A receptor antagonist may improve cognitive flexibility in individuals with ASD while also minimizing unwanted side effects.

The co-occurrence of autism and attention deficit hyperactivity disorder in children - what do we know?

Symptoms of attention deficit hyperactivity disorder (ADHD) and autistic spectrum disorder (ASD) often co-occur. The DSM-IV had specified that an ASD diagnosis is an exclusion criterion for ADHD, thereby limiting research of this common clinical co-occurrence. As neurodevelopmental disorders, both ASD and ADHD share some phenotypic similarities, but are characterized by distinct diagnostic criteria. The present review will examine the frequency and implications of this clinical co-occurrence in children, with an emphasis on the available data regarding pre-school age. The review will highlight possible etiologies explaining it, and suggest future research directions necessary to enhance our understanding of both etiology and therapeutic interventions, in light of the new DSM-V criteria, allowing for a dual diagnosis.

Effectiveness and tolerability of switching to aripiprazole from risperidone in subjects with autism spectrum disorders: a prospective open-label study

BACKGROUND

Subjects with autism spectrum disorders (ASDs) often exhibit behavioral symptoms such as aggressiveness and irritability. The purpose of this study was to examine the efficacy and the tolerability of aripiprazole switched from risperidone in children and adolescents with ASD.

METHODS

This prospective, 12-week, open-label study included 9 male subjects with ASD (age range, 9-22 years; mean ± SD age, 14.8 ± 4.0 years) followed up for 12 weeks after switching to aripiprazole from risperidone. The primary outcome measures were the Clinical Global Impression-Improvement scales and the irritability subscale of the Aberrant Behavior Checklist.

RESULTS

The mean ± SD maintenance dosages of risperidone and aripiprazole were 0.6 ± 0.4 mg/d and 4.8 ± 4.0 mg/d, respectively. The mean ± SD scores of the irritability subscale of the Aberrant Behavior Checklist before switching to aripiprazole (baseline) and 12 weeks after switching to aripiprazole (end point) were 14.8 ± 7.6 and 13.1 ± 8.0, respectively. The mean ± SD Clinical Global Impression-Improvement score, a comparison from baseline to end point, was 2.4 ± 0.7. Mild somnolence was observed only in 1 subject. No significant changes in vital signs, weight, electrocardiogram, or laboratory measures occurred during switching to aripiprazole. Serum prolactin levels decreased significantly from 17.3 ± 9.4 ng/mL (baseline) to 2.3 ± 1.7 ng/mL (end point).

CONCLUSIONS

The results show that aripiprazole might be generally well tolerated and might constitute an alternative treatment of subjects with ASD who experience poor efficacy or tolerability issues with risperidone treatment. Additional long-term controlled studies are needed to evaluate the efficacy and the safety of switching to aripiprazole from other antipsychotics in subjects with ASD.

The need for a comprehensive molecular characterization of autism spectrum disorders

Autism spectrum disorders (ASD) are a heterogeneous group of disorders which have complex behavioural phenotypes. Although ASD is a highly heritable neuropsychiatric disorder, genetic research alone has not provided a profound understanding of the underlying causes. Recent developments using biochemical tools such as transcriptomics, proteomics and cellular models, will pave the way to gain new insights into the underlying pathological pathways. This review addresses the state-of-the-art in the search for molecular biomarkers for ASD. In particular, the most important findings in the biochemical field are highlighted and the need for establishing streamlined interaction between behavioural studies, genetics and proteomics is stressed. Eventually, these approaches will lead to suitable translational ASD models and, therefore, a better disease understanding which may facilitate novel drug discovery efforts in this challenging field.

Habituation of exploratory behaviour in VPA rats: animal model of autism

Autism is a neurodevelopmental disorder with multifactorial aetiology, represented as impairment in social behaviour, communication and the occurrence of repetitive activities, which can be observed in the early life. The core features are frequently accompanied by other manifestations, including limited environmental exploration. The aim of the presented study, realised on an animal model of autism – VPA rats, i.e. animals prenatally affected with valproic acid on gestation day 12.5, was to investigate the habituation process of exploratory activity (manifested by a gradual decrease in the intensity of locomotor activity), which reflects the stage of the central nervous system. VPA rats were tested in open-field in three developmental periods – weaning (postnatal day 21 – PND 21), puberty (PND 42) and adulthood (PND 72). In each period of ontogenesis, the rapidity of habituation was evaluated by using the method of linear regression. Compared to controls, VPA rats showed a significant decrease in the intensity and an increase in the rapidity of exploratory activity habituation during puberty and adulthood. Our results indicate that the animal model of autism, i.e. VPA rats, showed disabilities in the development of the nervous system. These findings can help confirm not only the validity of this animal model of autism but can also help better understand neuronal changes in humans with autism.

Acetylcholine elevation relieves cognitive rigidity and social deficiency in a mouse model of autism

Autism spectrum disorders (ASD) are defined by behavioral deficits in social interaction and communication, repetitive stereotyped behaviors, and restricted interests/cognitive rigidity. Recent studies in humans and animal-models suggest that dysfunction of the cholinergic system may underlie autism-related behavioral symptoms. Here we tested the hypothesis that augmentation of acetylcholine (ACh) in the synaptic cleft by inhibiting acetylcholinesterase may ameliorate autistic phenotypes. We first administered the acetylcholinesterase inhibitor (AChEI) Donepezil systemically by intraperitoneal (i.p.) injections. Second, the drug was injected directly into the rodent homolog of the caudate nucleus, the dorsomedial striatum (DMS), of the inbred mouse strain BTBR T+tf/J (BTBR), a commonly-used model presenting all core autism-related phenotypes and expressing low brain ACh levels. We found that i.p. injection of AChEI to BTBR mice significantly relieved autism-relevant phenotypes, including decreasing cognitive rigidity, improving social preference, and enhancing social interaction, in a dose-dependent manner. Microinjection of the drug directly into the DMS, but not into the ventromedial striatum, led to significant amelioration of the cognitive-rigidity and social-deficiency phenotypes. Taken together, these findings provide evidence of the key role of the cholinergic system and the DMS in the etiology of ASD, and suggest that elevated cognitive flexibility may result in enhanced social attention. The potential therapeutic effect of AChEIs in ASD patients is discussed.

Self-injurious behaviour in autistic children: a neuro-developmental theory of social and environmental isolation

RATIONALE

Self-injurious behaviour is not one of the three core symptoms that define autism. However, children on the autism spectrum appear to be particularly vulnerable. Afflicted children typically slap their faces, punch or bang their heads, and bite or pinch themselves. These behaviours can be extremely destructive, and they interfere with normal social and educational activities. However, the neurobiological mechanisms that confer vulnerability in children with autism have not been adequately described.

OBJECTIVES

This review explores behavioural and neurobiological characteristics of children with autism that may be relevant for an increased understanding of their vulnerability for self-injurious behaviour.

METHODS

Behavioural characteristics that are co-morbid for self-injurious behaviour in children with autism are examined. In addition, the contributions of social and environmental deprivation in self-injurious institutionalized orphans, isolated rhesus macaques, and additional animal models are reviewed.

RESULTS

There is extensive evidence that social and environmental deprivation promotes self-injurious behaviour in both humans (including children with autism) and animal models. Moreover, there are multiple lines of convergent neuroanatomical, neurophysiological, and neurochemical data that draw parallels between self-injurious children with autism and environmentally deprived humans and animals.

CONCLUSIONS

A hypothesis is presented that describes how the core symptoms of autism make these children particularly vulnerable for self-injurious behaviour. Relevant neurodevelopmental pathology is described in cortical, limbic, and basal ganglia brain regions, and additional research is suggested.

Focusing on Cause or Cure?: Priorities and Stakeholder Presence in Childhood Psychiatry Research

BACKGROUND

Biomedical research is influenced by many factors, including the involvement of stakeholder groups invested in research outcomes. Stakeholder involvement in research efforts raise questions of justice as their specific interests and motivations play a role in directing research resources that ultimately produce knowledge shaping how different conditions (and affected individuals) are understood and treated by society. This issue is highly relevant to child psychiatry research where diagnostic criteria and treatment strategies are often controversial. Biological similarities and stakeholder differences between attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) provide an opportunity to explore this issue by comparing research foci and stakeholder involvement in these conditions.

METHODS

A subset of ADHD and ASD research articles published between 1970-2010 were randomly selected from the PubMed database and coded for research focus, funding source(s), and author-reported conflicts of interest (COIs). Chi-square analyses were performed to identify differences between and within ADHD and ASD research across time.

RESULTS

The proportion of ADHD research dedicated to basic, description, and treatment research was roughly similar and remained stable over time, while ASD research showed a significant increase in basic research over the past decade. Government was the primary research funder for both conditions, but for-profit funders were a notable presence in ADHD research, while joint-funding efforts between non-profit and government funders were a notable presence in ASD research. Lastly, COIs were noted more frequently in ADHD than in ASD research.

CONCLUSIONS

Our study shows significant differences in research foci and funding sources between the conditions, and identifies the specific involvement of for-profit and non-profit groups in ADHD and ASD, respectively. Our findings highlight the relationship between stakeholders outside the research community and research trajectories and suggest that examinations of these relationships must be included in broader considerations of biomedical research ethics.

Arousal and attention re-orienting in autism spectrum disorders: evidence from auditory event-related potentials

The extended phenotype of autism spectrum disorders (ASD) includes a combination of arousal regulation problems, sensory modulation difficulties, and attention re-orienting deficit. A slow and inefficient re-orienting to stimuli that appear outside of the attended sensory stream is thought to be especially detrimental for social functioning. Event-related potentials (ERPs) and magnetic fields (ERFs) may help to reveal which processing stages underlying brain response to unattended but salient sensory event are affected in individuals with ASD. Previous research focusing on two sequential stages of the brain response-automatic detection of physical changes in auditory stream, indexed by mismatch negativity (MMN), and evaluation of stimulus novelty, indexed by P3a component,-found in individuals with ASD either increased, decreased, or normal processing of deviance and novelty. The review examines these apparently conflicting results, notes gaps in previous findings, and suggests a potentially unifying hypothesis relating the dampened responses to unattended sensory events to the deficit in rapid arousal process. Specifically, "sensory gating" studies focused on pre-attentive arousal consistently demonstrated that brain response to unattended and temporally novel sound in ASD is already affected at around 100 ms after stimulus onset. We hypothesize that abnormalities in nicotinic cholinergic arousal pathways, previously reported in individuals with ASD, may contribute to these ERP/ERF aberrations and result in attention re-orienting deficit. Such cholinergic dysfunction may be present in individuals with ASD early in life and can influence both sensory processing and attention re-orienting behavior. Identification of early neurophysiological biomarkers for cholinergic deficit would help to detect infants "at risk" who can potentially benefit from particular types of therapies or interventions.

Obesity in children with autism spectrum disorder

Research suggests that the prevalence of obesity in children with autism spectrum disorder (ASD) is at least as high as that seen in typically developing children. Many of the risk factors for children with ASD are likely the same as for typically developing children, especially within the context of today's obesogenic environment. The particular needs and challenges that this population faces, however, may render them more susceptible to the adverse effects of typical risk factors, and they may also be vulnerable to additional risk factors not shared by children in the general population, including psychopharmacological treatment, genetics, disordered sleep, atypical eating patterns, and challenges for engaging in sufficient physical activity. For individuals with ASD, obesity and its sequelae potentially represent a significant threat to independent living, self-care, quality of life, and overall health.

Behavioral approaches to managing severe problem behaviors in children with autism spectrum and related developmental disorders: a descriptive analysis

Severe problem behaviors such as aggression, self-injury, and property destruction can result in injury, and require specialized and expensive treatment. This article reviews outcome research published since 1995 that used behavioral techniques to decrease severe problem behaviors among children and adolescents with autism spectrum disorder and/or intellectual disability. Many relatively simple interventions were reported to significantly reduce severe problem behavior, which offers hope for practitioners. Nonetheless, these studies also reveal a risk for injury and a need for specialized assessment and placement, careful tracking, and high-quality treatment that few agencies could likely replicate without increases in training and support.

Autism spectrum disorders: a pediatric overview and update

PURPOSE OF REVIEW

To provide an updated overview of autism spectrum disorders (ASDs), with particular attention to the pediatrician's role in assessing and managing patients with ASDs.

RECENT FINDINGS

Clinical perspectives on ASDs continue to evolve. The prevalence of ASDs in the United States continues to rise, and pediatricians are being tasked with the responsibility for universal screening. Further changes in its epidemiology will undoubtedly result from anticipated changes in the diagnostic criteria put forth in the upcoming revision to the Diagnostic and Statistical Manual (5th edition). Although there have been considerable advances in identifying a genetic cause in many more cases, the cause remains elusive in most cases. Recent studies of concordant twins suggest there is a stronger environmental component than previously believed. Research suggests earlier diagnosis may be feasible in some cases, and a new treatment approach has been shown to be effective in very young children. Although there have not been any large-scale advances in the medical treatment, some isolated successes have been reported and other promising therapies are now being investigated.

SUMMARY

Clinical guidelines for ASDs are evolving, with updated diagnostic criteria expected and revised recommendations for evaluation also imminent. This article provides pediatricians with a clinical overview of ASD - with an emphasis on the clinical considerations relating to screening, evaluation, and management.

Identifying essential cell types and circuits in autism spectrum disorders

Autism spectrum disorder (ASD) is highly genetic in its etiology, with potentially hundreds of genes contributing to risk. Despite this heterogeneity, these disparate genetic lesions may result in the disruption of a limited number of key cell types or circuits-information which could be leveraged for the design of therapeutic interventions. While hypotheses for cellular disruptions can be identified by postmortem anatomical analysis and expression studies of ASD risk genes, testing these hypotheses requires the use of animal models. In this review, we explore the existing evidence supporting the contribution of different cell types to ASD, specifically focusing on rodent studies disrupting serotonergic, GABAergic, cerebellar, and striatal cell types, with particular attention to studies of the sufficiency of specific cellular disruptions to generate ASD-related behavioral abnormalities. This evidence suggests multiple cellular routes can create features of the disorder, though it is currently unclear if these cell types converge on a final common circuit. We hope that in the future, systematic studies of cellular sufficiency and genetic interaction will help to classify patients into groups by type of cellular disruptions which suggest tractable therapeutic targets.

A randomised controlled trial of bumetanide in the treatment of autism in children

Gamma aminobutyric acid (GABA)-mediated synapses and the oscillations they orchestrate are altered in autism. GABA-acting benzodiazepines exert in some patients with autism paradoxical effects, raising the possibility that like in epilepsies, GABA excites neurons because of elevated intracellular concentrations of chloride. Following a successful pilot study,(1) we have now performed a double-blind clinical trial using the diuretic, chloride-importer antagonist bumetanide that reduces intracellular chloride reinforcing GABAergic inhibition. Sixty children with autism or Asperger syndrome (3-11 years old) received for 3 months placebo or bumetanide (1 mg daily), followed by 1-month wash out. Determination of the severity of autism was made with video films at day 0 (D0) and D90 by blind, independent evaluators. Bumetanide reduced significantly the Childhood Autism Rating Scale (CARS) (D90-D0; P<0.004 treated vs placebo), Clinical Global Impressions (P<0.017 treated vs placebo) and Autism Diagnostic Observation Schedule values when the most severe cases (CARS values above the mean ± s.d.; n=9) were removed (Wilcoxon test: P-value=0.031; Student's t-test: P-value=0.017). Side effects were restricted to an occasional mild hypokalaemia (3.0-3.5 mM l(-1) K(+)) that was treated with supplemental potassium. In a companion study, chronic bumetanide treatment significantly improved accuracy in facial emotional labelling, and increased brain activation in areas involved in social and emotional perception (Hadjikhani et al., submitted). Therefore, bumetanide is a promising novel therapeutic agent to treat autism. Larger trials are warranted to better determine the population best suited for this treatment.

Novel treatments in autism spectrum disorders: from synaptic dysfunction to experimental therapeutics

Recent discoveries and advances in genetics and neuroscience have provided deeper understanding of the complex neurobiology of ASD. The development of novel treatments is strictly dependent on these findings in order to design new strategies in the pharmacotherapy of ASD. At this time, therapeutics are limited to treating associated core, symptoms. Studies of single gene disorders, such as Phelan-McDermid syndrome, Fragile X and Tuberous Sclerosis, might be of significant help since the neurobiology of these disorders is clearer and clinical trials are already underway for these conditions. The pathogenesis paradigm shift of ASD towards synaptic abnormalities has led to current research of the pathways to disease, which involves multiple dynamic systems. Interest in oxytocin is growing as it has been recognized to be implicated in social development and affiliative behaviours. In the future, progress is expected in possible new options for therapeutics in ASD. Children and adolescents with ASD and their families can provide vital information about their experiences with new treatments, which should be a priority for future research.

Therapeutic drug monitoring of common antipsychotics

The aim of this review is to provide information for interpreting outcome results from monitoring of antipsychotics in biological samples. A brief overview of the working mechanisms, pharmacological effects, drug interactions, and analytical methods of classical and atypical antipsychotics is given. Nineteen antipsychotics were selected based on their importance in the worldwide market as follows: amisulpride, aripiprazole, asenapine, bromperidol, clozapine, flupenthixol, haloperidol, iloperidone, lurasidone, olanzapine, paliperidone, perphenazine, pimozide, pipamperone, quetiapine, risperidone, sertindole, sulpiride, and zuclopenthixol. A straightforward relationship between administered dose, plasma or serum concentration, clinical outcome, or adverse effects is often lacking. Nowadays, focus lies on therapeutic drug monitoring and individualized therapy to find adequate treatment, to explain treatment failure or nonresponse, and to check patient compliance. However, extensive research in this field is still mandatory.

Autism spectrum disorders: a review of measures for clinical, health services and cost-effectiveness applications

Autism spectrum disorders (ASDs) are characterized by impairments in social interaction, communication and behavioral functioning that can affect the health-related quality-of-life outcomes of the affected child and the family. ASDs have increased in prevalence, leading to a demand for improved understanding of the comparative effectiveness of different pharmacologic, behavioral, medical and alternative treatments for children as well as systems for providing services. This review describes outcome instruments that can be used for clinical, health services and cost-effectiveness applications. There is a pressing need to identify the most appropriate instruments for measuring health-related quality-of-life outcomes in this population. Studies evaluating the cost-effectiveness of interventions or treatments for children with ASDs using the cost per quality-adjusted life year metric are lacking. Researchers have the potential to contribute greatly to the field of autism by quantifying outcomes that can inform optimal treatment strategies.

Treatment for co-occurring attention deficit/hyperactivity disorder and autism spectrum disorder

Interest in the co-occurrence of attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) has grown in the last decade. Research on clinical populations supports the frequent co-occurrence of ADHD traits (e.g., hyperactivity) in individuals with ASD and ASD traits (e.g., social communication deficits) in individuals with ADHD. Similar trends in co-occurring traits have been observed in population-based samples, as well as family and genetic studies of affected individuals. Despite increased interest in co-occurring ADHD and ASD, relatively little research has been devoted to treatment considerations. The vast majority of intervention research has examined pharmacological treatment using traditional ADHD medications. Relatively few psychosocial interventions have directly addressed co-occurring symptoms. Treatment development will benefit from enhanced understanding of the phenomenon of co-occurring ADHD and ASD. Key topics for future research include examining developmental trajectories of co-occurring disorders, comorbid psychiatric conditions, deficits in social skills, and the nature of executive functioning impairment in individuals with co-occurring ADHD and ASD. In the current review, research in these areas is reviewed along with recommendation for future study. Given that clinicians are routinely observing and treating individuals with co-occurring symptoms, further research will yield needed information to inform intervention development and maximize benefits for affected individuals.

New directions in the treatment of autism spectrum disorders from animal model research

INTRODUCTION

Currently, there is not an effective pharmacotherapy for the core symptoms of the autism spectrum disorders (ASD), which include aberrant social behavior, delayed communication and repetitive behavior and/or restricted interests. There are several drugs that treat the symptoms associated with autism including irritability, aggressiveness and hyperactivity. Current drug research is based on the ongoing genetic, animal model and neuropathologic research. Two areas in particular, the glutamate and oxytocin systems, provide exciting new avenues for drug discovery.

AREAS COVERED

This review examines what approaches have been used for the drugs that are currently being used to treat people with ASD. For the most part, drugs that treat other neuropsychiatric disorders have been examined to treat the people with ASD, unfortunately with little effect on the core symptoms.

EXPERT OPINION

Until recently, there was not a plethora of knowledge about the neurobiological substrates of social behavior, pragmatic language usage and repetitive and/or restricted behaviors. Therefore, drug discovery has used the tools available for other neuropsychiatric disorders. Now that more biological information is available, there are many avenues for research for drug targets for ASD.

The use of omega-3 fatty acids in mental illness

PURPOSE

This article will summarize the current evidence on the effects of omega-3 fatty acids on prevention and treatment of mental illness.

BACKGROUND

Omega-3 fatty acids are involved in many physiologic processes. Since they cannot be made de novo in the body, they are considered essential nutrients. As the Western diet evolved, dietary intake of fatty acids has shifted to increased omega-6 fatty acids and decreased omega-3 fatty acids intake. These changes have been correlated with numerous differences in prevalence and course of mental illnesses.

METHODS

A MEDLINE search from 1966 to December 2010 was completed to identify studies comparing changes in symptoms, functioning, other outcomes, and/or side effects in patients treated with omega-3 fatty acids for mental illness. The studies were reviewed and reported by specific psychiatric disorder studied.

CONCLUSIONS

Omega-3 fatty acids play a role in many biologic functions. Epidemiologic data implicate omega-3 fatty acid deficiencies in many mental illnesses. Data are most robust for omega-3 fatty acids' role in affective disorders. However, data are conflicting, negative, or absent for most mental illnesses.

Issues in the management of challenging behaviours of adults with autism spectrum disorder

Autism spectrum disorder (ASD) is a particularly important risk factor for challenging behaviours such as aggression, tantrums, self-injury and pica. Adults with ASD have rarely been studied with respect to these problems. This is particularly disconcerting since there are far more adults than children with ASD. In addition, because of adults' increased physical size and longer history of these problems, treating these behaviours effectively is important. Psychological methods, particularly applied behaviour analysis, and pharmacotherapy have been the most frequently addressed treatments for challenging behaviours associated with ASD in the research literature. In many cases, challenging behaviours have clear environmental antecedents. In these cases, behavioural interventions, such as applied behaviour analysis, should be used to reduce the behaviours. When environmental factors cannot be identified or when challenging behaviours are very severe, pharmacological treatments may be necessary in combination with behavioural interventions. Newer antipsychotics are the most researched medications for use with this population. Currently, risperidone and aripiprazole are the only medications that have US FDA approval for the treatment of behaviours associated with ASD, specifically irritability; however, they are indicated for use in children not adults. It is important not to use medications unnecessarily, due to possible side effects associated with their use. Based on available research, some recommendations for the treatment of challenging behaviours of adults (and children) with ASD include the use of functional assessment, side-effect monitoring of medications and behavioural methods whenever possible. Additionally, future research in this area needs to focus more on adults, as most current research has used child samples.

The neurochemical basis for the treatment of autism spectrum disorders and Fragile X Syndrome

Autism spectrum disorders (ASD) and Fragile X Syndrome (FXS) are neurodevelopmental disorders that share overlapping behavioral characteristics. While FXS is known to result from a specific genetic mutation, the causes of the majority of cases of ASD are unknown. Animal models of FXS have revealed new insight into the cellular and biochemical changes that occur in the central nervous system in this disorder, while human genetic studies on individuals with autism have identified sets of genes that may increase susceptibility to the disorder. Together these discoveries suggest overlapping biochemical characteristics and reveal new directions for the potential development of pharmacological therapies that might prove useful in the treatment of both FXS and ASD. In particular, delayed synaptic maturation, abnormal synaptic structure and/or function and alterations in intracellular signaling pathways have been linked to the pathogenesis of FXS and ASD. Aberrations in GABA(A) receptor ion channels and the G-protein coupled metabotropic glutamate and GABA(B) transmitter systems are also linked to both disorders and these receptors are currently at the forefront of preclinical and clinical research into treatments for both autism and Fragile X Syndrome.