Psychopharmacological interventions in autism spectrum disorder

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.

Psychopharmacological treatments in Down syndrome and autism spectrum disorder: State of the research and practical considerations

Individuals with Down syndrome (DS) or Autism Spectrum Disorder (ASD), and especially those with both DS and co-occurring ASD (DS + ASD) commonly display behavioral and psychiatric symptoms that can impact quality of life and places increased burden on caregivers. While the mainstay of treatment in DS and ASD is focused on educational and behavioral therapies, pharmacological treatments can be used to reduce symptom burden. There is a paucity of evidence and limited clinical trials in DS and DS + ASD. Some scientific evidence is available, primarily in open label studies and case series that can guide treatment choices. Additionally, clinical decisions are often extrapolated from evidence and experience from those with ASD, or intellectual disability in those without DS. This article reviews current research in pharmacological treatment in DS, ASD, and DS + ASD, reviews co-occurring neurodevelopmental and mental health diagnoses in individuals with DS + ASD across the lifespan, and describes practical approaches to psychopharmacological management.

Vector enabled CRISPR gene editing - A revolutionary strategy for targeting the diversity of brain pathologies

Brain pathologies are considered one of the greatest contributors of death and disability worldwide. Neurodegenerative Alzheimer's disease is the second leading cause of death in adults, whilst brain cancers including glioblastoma multiforme in adults, and pediatric-type high-grade gliomas in children remain largely untreatable. A further compounding issue for patients with brain pathologies is that of long-term neuropsychiatric sequela - as a symptom or arising from high dose therapeutic intervention. The major challenge to effective, low dose treatment is finding therapeutics that successfully cross the blood-brain barrier and target aberrant cellular processes, while having minimum effect on essential cellular processes, and healthy bystander cells. Following over 30 years of research, CRISPR technology has emerged as a biomedical tour de force with the potential to revolutionise the treatment of both neurological and cancer related brain pathologies. The aim of this review is to take stock of the progress made in CRISPR technology in relation to treating brain pathologies. Specifically, we will describe studies which look beyond design, synthesis, and theoretical application; and focus instead on in vivo studies with translation potential. Along with discussing the latest breakthrough techniques being applied within the CRISPR field, we aim to provide a prospective on the knowledge gaps that exist and challenges that still lay ahead for CRISPR technology prior to successful application in the brain disease treatment field.

Appropriateness of psychopharmacological therapies to psychiatric diagnoses in persons with autism spectrum disorder with or without intellectual disabilities: a cross-sectional analytic study

BACKGROUND

Observational studies highlighted high rates of psychotropic medication in persons with autistic spectrum disorder (ASD) with or without intellectual disability, which seems to be associated with the management of problem behaviors more than co-occurrent psychiatric disorders. The purpose of the study is to investigate psychopharmacology use and diagnoses of co-occurrent psychiatric disorder (PD) in persons with ASD attending a public mental health service in Emilia Romagna, Italy.

METHODS

The present study is a multicenter, cross-sectional study.

RESULTS

275 persons out of 486 (56.5%) resulted to receive at least one psychotropic drug, compared to 74 persons (15.2%) that were diagnosed with a PD. 63.6% were on poly-pharmacotherapy (2-10 compounds), with 37.8% receiving 3 or more medications. Antipsychotics were the most frequently prescribed class of psychotropic drugs (89%), followed by antiepileptics/mood stabilizers/lithium (42.1%) and anxiolytics (BDZ) (38.5%). Most common psychiatric disorders were psychotic disorders (29.7%), followed by anxiety disorders (17.5%), bipolar disorders (12.2%), and depressive disorders (9.4%).

CONCLUSIONS

Our findings support earlier research showing that many individuals with ASD receive pharmacotherapy without being diagnosed with a co-occurring psychiatric disorder, indicating that the main reasons for prescription and the type of compound frequently have little to no link with specific psychopathology.

Efficacy and Safety of Diet Therapies in Children With Autism Spectrum Disorder: A Systematic Literature Review and Meta-Analysis

Objective

Autism Spectrum Disorder is a neurodevelopmental disorder, with a rapid increase in recognition over the past decade. Interest in alternative therapies is growing annually, such as dietary therapies including gluten-free and/or casein-free diet, and the ketogenic diet. However, there is no consensus on the efficacy and safety of dietary therapy in children with ASD up to now. This study aimed to assess the efficacy and safety of these diet interventions for children with ASD based on a meta-analysis of global data.

Methods

Seven databases (Cochrane Library, PubMed, EMBASE, Web of Science, VIP, CNKI, and Wanfang) were searched according to the established inclusion criteria, from the inception of the databases to August 18, 2021. The Cochrane Bias risk assessment tool was intended to assess the quality of the included studies. Review Manager 5.4 software was used as an efficacy analysis tool of the included studies, taking the core autistic symptoms and scales of ASD as therapeutic efficacy evaluations.

Results

In total, 7 RCTs with 338 participants were finally obtained. All studies assessed the association between core autistic symptoms and therapeutic diet, showing a statistically significant effect (standard mean difference (SMD) of −0.51, 95% confidence interval (Cl): −0.81 to −0.21), in which two studies which followed the GFD diet reported significant reductions in social behaviors (SMD of−0.41, 95% Cl: −0.75 to −0.06), showing no correlation with the length of the interventions (P < 0.05). Two studies were performed in KD diet suggested a significant effect in core symptoms (SMD of −0.67, 95% Cl: −1.04 to −0.31). No statistically significant changes were observed in the GFCF diet, GFD diet, cognition, communication, and stereotypical behaviors subgroups (all P > 0.05).

Conclusion

The results of a meta-analysis suggest that diet therapies can significantly ameliorate core symptoms of ASD, and GFD diets are conducive to improving social behaviors. Although the results suggest the effectiveness of dietary therapy for ASD, limited by the small sample size of RCTs, more well-designed, and high-quality clinical trials are needed to validate the above conclusions.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42021277565.

Nonpharmaceutical therapy for autism spectrum disorder: A protocol for systematic review and network meta-analysis

BACKGROUND

Autism spectrum disorder (ASD) is a widespread developmental disorder of the nervous system with an unclear etiology and pathogenesis. Its global incidence is currently increasing, and no effective drugs are available to improve its core symptoms. Nonpharmaceutical therapy can effectively relieve the core symptoms of autism, has fewer side effects than drugs, and is easily accepted by patients. This systematic and network meta-analysis aimed to evaluate the impact of non-pharmaceutical therapy on autism to explore preferable therapeutic options for autism.

METHODS

Online databases, including the China National Knowledge Infrastructure [CNKI], SinoMed, Wanfang Database [WF], China Science and Technology Journal Database [VIP], MEDLINE, Web of Science, EMBASE, and the Cochrane Library will be searched for randomized controlled trials of nonpharmacological interventions for autism published before October 2021. Two researchers will be independently responsible for the literature screening, data extraction, and quality assessment. Standard paired and Bayesian network meta-analyses will be performed using RevMan 5.3 Software and GEMTC 0.14.3, to compare the efficacy and safety of different nonpharmacological regimens.

RESULTS

The results of this systematic and network meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This study provides a comprehensive and reliable evidence-based reference for the efficacy and safety of different non-pharmacological interventions for autism.

PROSPERO REGISTRATION NUMBER

CRD 42021275571.

Systemic enhancement of serotonin signaling reverses social deficits in multiple mouse models for ASD

Autism spectrum disorder (ASD) is a common set of heterogeneous neurodevelopmental disorders resulting from a variety of genetic and environmental risk factors. A core feature of ASD is impairment in prosocial interactions. Current treatment options for individuals diagnosed with ASD are limited, with no current FDA-approved medications that effectively treat its core symptoms. We recently demonstrated that enhanced serotonin (5-HT) activity in the nucleus accumbens (NAc), via optogenetic activation of 5-HTergic inputs or direct infusion of a specific 5-HT1b receptor agonist, reverses social deficits in a genetic mouse model for ASD based on 16p11.2 copy number variation. Furthermore, the recreational drug MDMA, which is currently being evaluated in clinical trials, promotes sociability in mice due to its 5-HT releasing properties in the NAc. Here, we systematically evaluated the ability of MDMA and a selective 5-HT1b receptor agonist to rescue sociability deficits in multiple different mouse models for ASD. We find that MDMA administration enhances sociability in control mice and reverses sociability deficits in all four ASD mouse models examined, whereas administration of a 5-HT1b receptor agonist selectively rescued the sociability deficits in all six mouse models for ASD. These preclinical findings suggest that pharmacological enhancement of 5-HT release or direct 5-HT1b receptor activation may be therapeutically efficacious in ameliorating some of the core sociability deficits present across etiologically distinct presentations of ASD.

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.

Implication of the social function of excessive self-grooming behavior in BTBR T+ltpr3tf/J mice as an idiopathic model of autism

Autism spectrum disorder (ASD) is defined by two core behavioral characteristics, namely, restricted repetitive behaviors and impaired social-communicative functioning. BTBR T⁺ltpr3^tf/J (BTBR) mice provide a valuable animal model for ASD to elucidate the underlying mechanisms of these two behavioral characteristics of ASD. This study examined the social function of excessive grooming behavior in BTBR mice as a phenotype of restricted repetitive behaviors. Compared to the control C57BL/6 J (B6) strain, BTBR mice showed increased self-grooming when placed alone in a test apparatus, and this behavior was even more evident when confronted with a stimulus mouse (either B6 or BTBR) in a three-chamber test apparatus. While B6 mice tended to groom their face/snout region on the empty side of the chamber, BTBR mice showed excessive grooming with frequent transitions among grooming body regions on the side of the chamber containing a social stimulus. Acute systemic injection of buspirone,a serotonin 1A receptor agonist, as an anxiolytic, facilitated approach behavior toward social stimuli in the three-chamber setting in both B6 and BTBR mice. However, this treatment did not affect grooming behavior in B6 mice and significantly enhanced self-grooming in BTBR mice. These behaviors in BTBR mice suggest a potential signaling function of grooming in response to social stimuli, in which bodywide grooming of BTBR mice expressed in the proximity of social opponents may stimulate the release of olfactory (possibly dismissive) signals. Consequently, the putative neural mechanisms underlying excessive grooming may differ from those regulating social approaches that are associated with anxiolytic mechanisms.

Regulation Of Microtubule: Current Concepts And Relevance To Neurodegenerative Diseases

Neurodevelopmental disorders (NDDs) are abnormalities linked to neuronal structure and irregularities associated with the proliferation of cells, transportation, and differentiation. NDD also involves synaptic circuitry and neural network alterations known as synaptopathies. Microtubules (MTs) and MTs-associated proteins help to maintain neuronal health as well as their development. The microtubular dynamic structure plays a crucial role in the division of cells and forms mitotic spindles, thus take part in initiating stages of differentiation and polarization for various types of cells. The MTs also take part in the cellular death but MT-based cellular degenerations are not yet well excavated. In the last few years, studies have provided the protagonist activity of MTs in neuronal degeneration. In this review, we largely engrossed our discussion on the change of MT cytoskeleton structure, describing their organization, dynamics, transportation, and their failure causing NDDs. At end of this review, we are targeting the therapeutic neuroprotective strategies on clinical priority and also try to discuss the clues for the development of new MT-based therapy as a new pharmacological intervention. This will be a new potential site to block not only neurodegeneration but also promotes the regeneration of neurons.

Risk of Substance Use Disorder and Its Associations With Comorbidities and Psychotropic Agents in Patients With Autism

IMPORTANCE

The risk of substance use disorder (SUD) in patients with autism spectrum disorder (ASD) remains unclear.

OBJECTIVE

To investigate the risk of SUD in patients with ASD and its associations with comorbidities, psychotropic agents (PAs), and mortality.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, population-based, cohort study of 1 936 512 participants used data from the Taiwan National Health Insurance Research Database and was conducted from January 1, 2000, to December 31, 2015. Included participants attended at least 3 outpatient visits within the 1-year study period for symptomatic ASD as determined by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnostic codes. Individuals diagnosed with ASD before 2000, those diagnosed with SUD before the first visit for ASD, and those with missing data were excluded from the analysis. Patients with ASD and non-ASD controls were matched 1:4 by age, sex, and index date.

EXPOSURES

Symptomatic ASD evaluated for at least 3 outpatient visits within the 1-year study period.

MAIN OUTCOMES AND MEASURES

Adjusted hazard ratios (aHRs) with 95% CIs for SUD, including alcohol use disorder (AUD) and drug use disorder (DUD), and the risk of mortality were calculated. Data were analyzed from March 1 to July 13, 2020.

RESULTS

A total of 6599 individuals with ASD (mean [SD] age, 11.9 [5.1] years; 5094 boys [77.2%]; mean [SD] follow-up period, 8.1 [8.3] years; median follow-up period, 4.3 [interquartile range [IQR], 2.3-5.3] years) and 26 396 controls (mean [SD] age, 12.1 [5.8] years; 20 376 boys [77.2%]; mean [SD] follow-up period, 8.6 [8.9] years; median follow-up period, 4.4 [IQR, 2.4-5.4] years) were enrolled in the study. According to multivariable-adjusted analysis, the aHRs for SUD (2.33; 95% CI, 1.89-2.87), AUD (2.07; 95% CI, 1.60-2.63), and DUD (3.00; 95% CI, 2.15-4.58) were significantly higher in the ASD group than in the non-ASD controls. The aHRs for SUD in the ASD subgroups with 1 PA (0.60; 95% CI, 0.43-0.66) and with multiple PAs (0.37; 95% CI, 0.28-0.49) were significantly lower than those in the ASD subgroup with no PAs. Comparisons between patients with ASD and non-ASD controls with the same comorbidities showed higher aHRs for SUD among patients with ASD (range, 1.17-2.55); moreover, the ASD subgroup not receiving any PAs had an aHR of 6.39 (95% CI, 5.11-7.87) for SUD when they had comorbid tic disorder and aHRs of 5.48 (95% CI, 5.12-5.70) for AUD and 5.42 (95% CI, 5.12-5.80) for DUD when they had comorbid impulse control disorder. The mortality risk was significantly higher in patients with ASD and concomitant SUD than in non-ASD controls without SUD (aHR, 3.17; 95% CI, 2.69-3.89).

CONCLUSIONS AND RELEVANCE

These findings suggest that patients with ASD are vulnerable to the development of SUD. Comorbid ASD and SUD were associated with an increase in mortality risk.

Neurotransmitter, Antioxidant and Anti-neuroinflammatory Mechanistic Potentials of Herbal Medicines in Ameliorating Autism Spectrum Disorder

BACKGROUND

Autism spectrum disorder (ASD) is a neurodevelopmental issue that disrupts behavior, nonverbal communication, and social interaction, impacting all aspects of an individual's social development. The underlying origin of autism is unclear, however, oxidative stress, as well as serotonergic, adrenergic and dopaminergic systems are thought to be implicated in ASD. Despite the fact that there is no effective medication for autism, current pharmacological treatments are utilized to ameliorate some of the symptoms such as selfmutilation, aggression, repetitive and stereotyped behaviors, inattention, hyperactivity, and sleep disorders.

METHODS

In accord with the literature regarding the activity of herbal medicines on neurotransmitter function, we aimed to review the most worthy medicinal herbs possessing neuroprotective effects.

RESULTS

Based on the outcome, medicinal herbs such as Zingiber officinale, Astragalus membranaceu, Ginkgo biloba, Centella asiatica and Acorus calamus, have antioxidant activity, which can influence neurotransmitter systems and are potentially neuroprotective.

CONCLUSION

Consequently, these herbs, in theory at least, appear to be suitable candidates within an overall management strategy for those on the autism spectrum.

Development of a Digital Content-Free Speech Analysis Tool for the Measurement of Mental Health and Follow-Up for Mental Disorders: Protocol for a Case-Control Study

BACKGROUND

The prevalence of mental disorders worldwide is very high. The guideline-oriented care of patients depends on early diagnosis and regular and valid evaluation of their treatment to be able to quickly intervene should the patient's mental health deteriorate. To ensure effective treatment, the level of experience of the physician or therapist is of importance, both in the initial diagnosis and in the treatment of mental illnesses. Nevertheless, experienced physicians and psychotherapists are not available in enough numbers everywhere, especially in rural areas or in less developed countries. Human speech can reveal a speaker's mental state by altering its noncontent aspects (speech melody, intonations, speech rate, etc). This is noticeable in both the clinic and everyday life by having prior knowledge of the normal speech patterns of the affected person, and with enough time spent listening to the patient. However, this time and experience are often unavailable, leaving unused opportunities to capture linguistic, noncontent information. To improve the care of patients with mental disorders, we have developed a concept for assessing their most important mental parameters through a noncontent analysis of their active speech. Using speech analysis for the assessment and tracking of mental health patients opens up the possibility of remote, automatic, and ongoing evaluation when used with patients' smartphones, as part of the current trends toward the increasing use of digital and mobile health tools.

OBJECTIVE

The primary objective of this study is to evaluate measurements of participants' mental state by comparing the analysis of noncontent speech parameters to the results of several psychological questionnaires (Symptom Checklist-90 [SCL-90], the Patient Health Questionnaire [PHQ], and the Big 5 Test).

METHODS

In this paper, we described a case-controlled study (with a case group and one control group). The participants will be recruited in an outpatient neuropsychiatric treatment center. Inclusion criteria are a neurological or psychiatric diagnosis made by a specialist, no terminal or life-threatening illnesses, and fluent use of the German language. Exclusion criteria include psychosis, dementia, speech or language disorders in neurological diseases, addiction history, a suicide attempt recently or in the last 12 months, or insufficient language skills. The measuring instrument will be the VoiceSense digital voice analysis tool, which enables the analysis of 200 specific speech parameters, and the assessment of findings using psychometric instruments and questionnaires (SCL-90, PHQ, Big 5 Test).

RESULTS

The study is ongoing as of September 2019, but we have enrolled 254 participants. There have been 161 measurements completed at timepoint 1, and a total of 62 participants have completed every psychological and speech analysis measurement.

CONCLUSIONS

It appears that the tone and modulation of speech are as important, if not more so, than the content, and should not be underestimated. This is particularly evident in the interpretation of the psychological findings thus far acquired. Therefore, the application of a software analysis tool could increase the accuracy of finding assessments and improve patient care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03700008; https://clinicaltrials.gov/ct2/show/NCT03700008.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/13852.

Identification, Evaluation, and Management of Children With Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder with reported prevalence in the United States of 1 in 59 children (approximately 1.7%). Core deficits are identified in 2 domains: social communication/interaction and restrictive, repetitive patterns of behavior. Children and youth with ASD have service needs in behavioral, educational, health, leisure, family support, and other areas. Standardized screening for ASD at 18 and 24 months of age with ongoing developmental surveillance continues to be recommended in primary care (although it may be performed in other settings), because ASD is common, can be diagnosed as young as 18 months of age, and has evidenced-based interventions that may improve function. More accurate and culturally sensitive screening approaches are needed. Primary care providers should be familiar with the diagnostic criteria for ASD, appropriate etiologic evaluation, and co-occurring medical and behavioral conditions (such as disorders of sleep and feeding, gastrointestinal tract symptoms, obesity, seizures, attention-deficit/hyperactivity disorder, anxiety, and wandering) that affect the child's function and quality of life. There is an increasing evidence base to support behavioral and other interventions to address specific skills and symptoms. Shared decision making calls for collaboration with families in evaluation and choice of interventions.  This single clinical report updates the 2007 American Academy of Pediatrics clinical reports on the evaluation and treatment of ASD in one publication with an online table of contents and section view available through the American Academy of Pediatrics Gateway to help the reader identify topic areas within the report.

Early genistein exposure of California mice and effects on the gut microbiota-brain axis

Human offspring encounter high amounts of phytoestrogens, such as genistein (GEN), through maternal diet and soy-based formulas. Such chemicals can exert estrogenic activity and thereby disrupt neurobehavioral programming. Besides inducing direct host effects, GEN might cause gut dysbiosis and alter gut metabolites. To determine whether exposure to GEN affects these parameters, California mice (Peromyscus californicus) dams were placed 2 weeks prior to breeding and throughout gestation and lactation on a diet supplemented with GEN (250 mg/kg feed weight) or AIN93G phytoestrogen-free control diet (AIN). At weaning, offspring socio-communicative behaviors, gut microbiota and metabolite profiles were assayed. Exposure of offspring to GEN-induced sex-dependent changes in gut microbiota and metabolites. GEN exposed females were less likely to investigate a novel female mouse when tested in a three-chamber social test. When isolated, GEN males and females exhibited increased latency to elicit their first call, suggestive of reduced motivation to communicate with other individuals. Correlation analyses revealed interactions between GEN-induced microbiome, metabolome and socio-communicative behaviors. Comparison of GEN males with AIN males revealed the fraction of calls above 20 kHz was associated with daidzein, α-tocopherol, Flexispira spp. and Odoribacter spp. Results suggest early GEN exposure disrupts normal socio-communicative behaviors in California mice, which are otherwise evident in these social rodents. Such effects may be due to GEN disruptions on neural programming but might also be attributed to GEN-induced microbiota shifts and resultant changes in gut metabolites. Findings indicate cause for concern that perinatal exposure to GEN may detrimentally affect the offspring microbiome-gut-brain axis.

Vascular RAGE transports oxytocin into the brain to elicit its maternal bonding behaviour in mice

Oxytocin sets the stage for childbirth by initiating uterine contractions, lactation and maternal bonding behaviours. Mice lacking secreted oxcytocin (Oxt^−/−, Cd38^−/−) or its receptor (Oxtr^−/−) fail to nurture. Normal maternal behaviour is restored by peripheral oxcytocin replacement in Oxt^−/− and Cd38^−/−, but not Oxtr^−/− mice, implying that circulating oxcytocin crosses the blood-brain barrier. Exogenous oxcytocin also has behavioural effects in humans. However, circulating polypeptides are typically excluded from the brain. We show that oxcytocin is transported into the brain by receptor for advanced glycation end-products (RAGE) on brain capillary endothelial cells. The increases in oxcytocin in the brain which follow exogenous administration are lost in Ager^−/− male mice lacking RAGE, and behaviours characteristic to abnormalities in oxcytocin signalling are recapitulated in Ager^−/− mice, including deficits in maternal bonding and hyperactivity. Our findings show that RAGE-mediated transport is critical to the behavioural actions of oxcytocin associated with parenting and social bonding.

Yasuhiko Yamamoto et al. show that oxytocin is transported into the brain by the receptor for advanced glycation end-products (RAGE) on the blood-brain barrier. This study explains how circulating oxytocin crosses the blood-brain barrier, which is important to manifest oxytocin’s maternal bonding effects.

ADHD in children and youth: Part 3-Assessment and treatment with comorbid ASD, ID, or prematurity

Attention-deficit hyperactivity disorder (ADHD) is a chronic neurodevelopmental disorder. Three position statements have been developed by the Canadian Paediatric Society, following systematic literature reviews. Statement objectives are to: 1) Summarize the current clinical evidence regarding ADHD,2) Establish a standard for ADHD care, and3) Assist Canadian clinicians in making well-informed, evidence-based decisions to enhance care of children and youth with this condition. Specific topics reviewed in Part 3, which focuses on associated autism spectrum disorder, intellectual disability, and prematurity, include the challenges of diagnostic assessment, common presentations, the role of genetics, and treatment, including the benefits of physical activity. Recommendations are based on current guidelines, evidence from the literature, and expert consensus.

Characterization of Medication Use in a Multicenter Sample of Pediatric Inpatients with Autism Spectrum Disorder

Nearly 11% of youth with Autism Spectrum Disorder (ASD) undergo psychiatric hospitalization, and 65% are treated with psychotropic medication. Here we characterize psychotropic medication usage in subjects enrolled in the Autism Inpatient Collection. Participant psychotropic medication usage rates topped 90% at admission and discharge, though there was a decline at 2-month follow-up. Antipsychotics, ADHD medications, and sleep aids were the most commonly reported classes of medications. The impact of age, gender, and non-verbal IQ on medication usage rates was minimal, though age and IQ may play a role in prescribing practices. Future work is indicated to explore medication usage trends, the impact of clinical factors on medication use rates, and the safety of psychotropic medications in youth with ASD.

Using Pupillometry to Assess the Atypical Pupillary Light Reflex and LC-NE System in ASD

With recent advances in technology, there has been growing interest in use of eye-tracking and pupillometry to assess the visual pathway in autism spectrum disorder (ASD). Within emerging literature, an atypical pupillary light reflex (PLR) has been documented, holding potential for use as a clinical screening biomarker for ASD. This review outlines dominant theories of neuropathology associated with ASD and integrates underlying neuroscience associated with the atypical PLR through a reciprocal model of brainstem involvement and cortical underconnectivity. This review draws from animal models of ASD demonstrating disruption of cranial motor nuclei and brain imaging studies examining arousal and the influence of the locus coeruleus norepinephrine (LC-NE) system on the pupillary response. Pupillometry methods are explained in relation to existing data examining the PLR in ASD and pupillary parameters of constriction latency and tonic pupil diameter as key parameters for investigation. This focused review provides preliminary data toward future work developing pupillometry metrics and offers direction for studies aimed at rigorous study replication using pupillometry with the ASD population. Experimental conditions and testing protocol for capturing pupil parameters with this clinical population are discussed to promote clinical research and translational application.

5-HT release in nucleus accumbens rescues social deficits in mouse autism model

Dysfunction in prosocial interactions is a core symptom of autism spectrum disorder. However, the neural mechanisms that underlie sociability are poorly understood, limiting the rational development of therapies to treat social deficits. Here we show in mice that bidirectional modulation of the release of serotonin (5-HT) from dorsal raphe neurons in the nucleus accumbens bidirectionally modifies sociability. In a mouse model of a common genetic cause of autism spectrum disorder-a copy number variation on chromosome 16p11.2-genetic deletion of the syntenic region from 5-HT neurons induces deficits in social behaviour and decreases dorsal raphe 5-HT neuronal activity. These sociability deficits can be rescued by optogenetic activation of dorsal raphe 5-HT neurons, an effect requiring and mimicked by activation of 5-HT1b receptors in the nucleus accumbens. These results demonstrate an unexpected role for 5-HT action in the nucleus accumbens in social behaviours, and suggest that targeting this mechanism may prove therapeutically beneficial.

Nanoparticle delivery of CRISPR into the brain rescues a mouse model of fragile X syndrome from exaggerated repetitive behaviours

Technologies that can safely edit genes in the brains of adult animals may revolutionize the treatment of neurological diseases and the understanding of brain function. Here, we demonstrate that intracranial injection of CRISPR-Gold, a nonviral delivery vehicle for the CRISPR-Cas9 ribonucleoprotein, can edit genes in the brains of adult mice in multiple mouse models. CRISPR-Gold can deliver both Cas9 and Cpf1 ribonucleoproteins, and can edit all of the major cell types in the brain, including neurons, astrocytes and microglia, with undetectable levels of toxicity at the doses used. We also show that CRISPR-Gold designed to target the metabotropic glutamate receptor 5 (mGluR5) gene can efficiently reduce local mGluR5 levels in the striatum after an intracranial injection. The effect can also rescue mice from the exaggerated repetitive behaviours caused by fragile X syndrome, a common single-gene form of autism spectrum disorders. CRISPR-Gold may significantly accelerate the development of brain-targeted therapeutics and enable the rapid development of focal brain-knockout animal models.

Dried Blood Spots Combined With Ultra-High-Performance Liquid Chromatography-Mass Spectrometry for the Quantification of the Antipsychotics Risperidone, Aripiprazole, Pipamperone, and Their Major Metabolites

BACKGROUND

Risperidone, aripiprazole, and pipamperone are antipsychotic drugs frequently prescribed for the treatment of comorbid behavioral problems in children with autism spectrum disorders. Therapeutic drug monitoring (TDM) could be useful to decrease side effects and to improve patient outcome. Dried blood spot (DBS) sample collection seems to be an attractive technique to develop TDM of these drugs in a pediatric population. The aim of this work was to develop and validate a DBS assay suitable for TDM and home sampling.

METHODS

Risperidone, 9-OH risperidone, aripiprazole, dehydroaripiprazole, and pipamperone were extracted from DBS and analyzed by ultra-high-performance liquid chromatography-tandem mass spectrometry using a C18 reversed-phase column with a mobile phase consisting of ammonium acetate/formic acid in water or methanol. The suitability of DBS for TDM was assessed by studying the influence of specific parameters: extraction solution, EDTA carryover, hematocrit, punching location, spot volume, and hemolysis. The assay was validated with respect to conventional guidelines for bioanalytical methods.

RESULTS

The method was linear, specific without any critical matrix effect, and with a mean recovery around 90%. Accuracy and imprecision were within the acceptance criteria in samples with hematocrit values from 30% to 45%. EDTA or hemolysis did not skew the results, and no punching carryover was observed. No significant influence of the spot volume or the punch location was observed. The antipsychotics were all stable in DBS stored 10 days at room temperature and 1 month at 4 or -80°C. The method was successfully applied to quantify the 3 antipsychotics and their metabolites in patient samples.

CONCLUSIONS

A UHPLC-MS/MS method has been successfully validated for the simultaneous quantification of risperidone, 9-OH risperidone, aripiprazole, dehydroaripiprazole, and pipamperone in DBS. The assay provided good analytical performances for TDM and clinical research applications.

Factors Associated with Developmental Behavioral Pediatricians Prescribing Psychotropic Medication to Children with Autism Spectrum Disorder: A Study of Three DBPNet Sites

OBJECTIVE

Psychotropic medications are frequently prescribed to children with autism spectrum disorder (ASD), but little is known about the prescribing practices of developmental-behavioral pediatricians (DBPs). Our objective was to determine whether clinical site, age, insurance, or comorbidities influenced DBPs prescribing psychotropic medication for children with ASD.

METHODS

A retrospective analysis was performed using electronic health record data of all patients with ASD seen at 3 academic developmental-behavioral pediatrics (DBP) clinical programs from January 2010 to December 2011. Data included age, diagnoses, primary insurance, and medications prescribed. Factors associated with prescribing psychotropic medication were examined using generalized estimating equations.

RESULTS

Sites varied in the frequency with which they prescribed psychotropic medication for children with ASD (site 1: 33.1%, site 2: 49.3%, site 3: 4.0%; p < .001). We found that the following factors predicted prescribing of psychotropic medications: comorbidities (odds ratio [OR]: 2.87; 95% confidence interval [CI], 2.58-3.18), age, and primary insurance. However, the impact of insurance depended on age. For 3- to 5-year-old children, those on Medicaid were more likely to be prescribed psychotropic medications than those with private insurance (OR: 1.65; 95% CI, 1.29-2.12). This was particularly true for alpha-2-adrenergic agonists (OR: 2.48; 95% CI, 1.56-3.92) and atypical antipsychotics (OR: 2.57; 95% CI, 1.46-4.55).

CONCLUSION

There are large variations in prescribing psychotropic medication to children with ASD at 3 academic DBP programs. Further research is needed to understand factors that contribute to higher use of psychotropic medication in young children with Medicaid.

Tryptophan status in autism spectrum disorder and the influence of supplementation on its level

Recent reports show that the worldwide incidence of autism spectrum disorder (ASD) is dramatically increasing, although ASD etiology and pathogenesis are still far to be fully elucidated. Some dietary-derived essential compounds, such as the amino acid tryptophan, appear to be impaired in patients with ASD. Tryptophan (Trp) plays a significant role in the human organism and serves as a precursor for a wide range of bioactive compounds, including major neurotransmitters. Research indicates that tryptophan might be deficient in subjects with ASD. Deficiency in the tryptophan level can be retrieved by investigating Trp levels or its major metabolite kynurenine in urines. The purpose of the present study is to quantify tryptophan content in urine samples (n = 236) of ASD patients, who underwent a supplemented dietary panel with B vitamins and magnesium, compared to controls (without this diet regimen). The samples were analyzed with gas chromatography-mass spectrometry. Additionally, the correlation between body mass index (BMI) and the level of this amino acid in urine was accomplished. Basic parameters of urine samples were also evaluated. Statistical evaluations in the concentration of tryptophan in ASD patients with different severity of symptoms were reported. A significant difference in tryptophan levels in all groups was observed. Supplementation with B vitamins and magnesium has an influence on the Trp concentration. Furthermore, no correlation between BMI and tryptophan levels was found. These results assess that the Trp level in ASD subjects is critical and that intake of B vitamins and magnesium with diet might influence its metabolic homeostasis.

Potential Role of Microtubule Stabilizing Agents in Neurodevelopmental Disorders

Neurodevelopmental disorders (NDDs) are characterized by neuroanatomical abnormalities indicative of corticogenesis disturbances. At the basis of NDDs cortical abnormalities, the principal developmental processes involved are cellular proliferation, migration and differentiation. NDDs are also considered “synaptic disorders” since accumulating evidence suggests that NDDs are developmental brain misconnection syndromes characterized by altered connectivity in local circuits and between brain regions. Microtubules and microtubule-associated proteins play a fundamental role in the regulation of basic neurodevelopmental processes, such as neuronal polarization and migration, neuronal branching and synaptogenesis. Here, the role of microtubule dynamics will be elucidated in regulating several neurodevelopmental steps. Furthermore, the correlation between abnormalities in microtubule dynamics and some NDDs will be described. Finally, we will discuss the potential use of microtubule stabilizing agents as a new pharmacological intervention for NDDs treatment.

Pharmacogenomics and Efficacy of Risperidone Long-Term Treatment in Thai Autistic Children and Adolescents

The purpose of this study was to evaluate the association of pharmacogenomic factors and clinical outcome in autistic children and adolescents who were treated with risperidone for long periods. Eighty-two autistic subjects diagnosed with DSM-IV and who were treated with risperidone for more than 1 year were recruited. Pharmacogenomics and clinical outcome (CGI-I, aggressive, overactivity and repetitive score) were evaluated. Almost all patients showed stable symptoms on aggressive behaviour (89.02%), overactivity (71.95%), repetitive (70.89%) behaviour and all clinical symptoms (81.71%). Only 4.48% of patients showed minimally worse CGI-I score. Patients in the non-stable symptom group had DRD2 Taq1A non-wild-type (TT and CT) frequencies higher than the clinically stable group (p = 0.04), whereas other gene polymorphisms showed no significant association. Haplotype ACCTCAT (rs6311, rs1045642, rs1128503, rs1800497, rs4436578, rs1799978, rs6280) showed a significant association with non-stable clinical outcome (χ²  = 6.642, p = 0.010). Risperidone levels showed no association with any clinical outcome. On the other hand, risperidone dose, 9-OH risperidone levels and prolactin levels were significantly higher in the non-stable compared to the stable symptom group (p = 0.013, p = 0.044, p = 0.030). Increased appetite was the most common adverse drug reaction and associated with higher body-weight, whereas it was not significantly associated with genetic variations and non-genetic information. In conclusion, risperidone showed efficacy to control autism, especially aggressive symptoms in long-term treatment. However, Taq1A T - carrier of dopamine 2 receptor gene - is associated with non-stable response in risperidone-treated patients. This study supports pharmacogenomics testing for personalized therapy with risperidone in autistic children and adolescents.

The Association Between Comorbid Autism Spectrum Disorders and Antipsychotic Treatment Failure in Early-Onset Psychosis: A Historical Cohort Study Using Electronic Health Records

OBJECTIVE

In a sample of children and adolescents with first-episode psychosis, we investigated whether multiple treatment failure (MTF, defined as the initiation of a third trial of novel antipsychotic due to nonadherence, adverse effects, or insufficient response) was associated with comorbid autism spectrum disorders.

METHODS

Data were from the electronic health records of 638 children (51% male) aged from 10 to 17 years with first-episode psychosis (per ICD-10 criteria) from January 1, 2008, to November 1, 2014, referred to mental health services in South London, United Kingdom; data were extracted using the Clinical Record Interactive Search (CRIS) system. The effect of autism spectrum disorder comorbidity on the development of MTF during a 5-year period was modeled using Cox regression.

RESULTS

There were 124 cases of MTF prior to the age of 18 (19.4% of the sample). Comorbid autism spectrum disorders were significantly associated with MTF (adjusted hazard ratio = 1.99; 95% CI, 1.19-3.31; P = .008) after controlling for a range of potential confounders. Other factors significantly associated with MTF included higher age at first presentation (P = .001), black ethnicity (P = .03), and frequency of clinical contact (P < .001). No significant association between other comorbid neurodevelopmental disorders (hyperkinetic disorder or intellectual disability) and MTF was found.

CONCLUSIONS

Children with first-episode psychosis and comorbid autism spectrum disorders at first presentation are less likely to have a beneficial response to antipsychotics.

Lurasidone for the Treatment of Irritability Associated with Autistic Disorder

The aim of this study was to evaluate the short-term efficacy and safety of lurasidone in treating irritability associated with autistic disorder. In this multicenter trial, outpatients age 6–17 years who met DSM-IV-TR criteria for autistic disorder, and who demonstrated irritability, agitation, and/or self-injurious behaviors were randomized to 6 weeks of double-blind treatment with lurasidone 20 mg/day (N = 50), 60 mg/day (N = 49), or placebo (N = 51). Efficacy measures included the Aberrant Behavior Checklist Irritability subscale (ABC-I, the primary endpoint) and the Clinical Global Impressions, Improvement (CGI-I) scale, and were analyzed using a likelihood-based mixed model for repeated measures. Least squares (LS) mean (standard error [SE]) improvement from baseline to Week 6 in the ABC-I was not significantly different for lurasidone 20 mg/day (−8.8 [1.5]) and lurasidone 60 mg/day (−9.4 [1.4]) versus placebo (−7.5 [1.5]; p = 0.55 and 0.36, respectively). CGI-I scores showed significantly greater LS mean [SE] improvement at Week 6 for lurasidone 20 mg/day versus placebo (2.8 [0.2] vs. 3.4 [0.2]; p = 0.035) but not for lurasidone 60 mg/day (3.1 [0.2]; p = 0.27). Discontinuation rates due to adverse events were: lurasidone 20 mg/day, 4.1 %; 60 mg/day, 3.9 %; and placebo, 8.2 %. Adverse events with an incidence ≥10 % (lurasidone combined, placebo) included vomiting (18.0, 4.1 %) and somnolence (12.0, 4.1 %). Modest changes were observed in weight and selected metabolic parameters. In this study, once-daily, fixed doses of 20 and 60 mg/day of lurasidone were not demonstrated to be efficacious compared to placebo for the short-term treatment of children and adolescents with moderate-to-severe irritability associated with autistic disorder.

Brain oscillations and connectivity in autism spectrum disorders (ASD): new approaches to methodology, measurement and modelling

Although atypical social behaviour remains a key characterisation of ASD, the presence of sensory and perceptual abnormalities has been given a more central role in recent classification changes. An understanding of the origins of such aberrations could thus prove a fruitful focus for ASD research. Early neurocognitive models of ASD suggested that the study of high frequency activity in the brain as a measure of cortical connectivity might provide the key to understanding the neural correlates of sensory and perceptual deviations in ASD. As our review shows, the findings from subsequent research have been inconsistent, with a lack of agreement about the nature of any high frequency disturbances in ASD brains. Based on the application of new techniques using more sophisticated measures of brain synchronisation, direction of information flow, and invoking the coupling between high and low frequency bands, we propose a framework which could reconcile apparently conflicting findings in this area and would be consistent both with emerging neurocognitive models of autism and with the heterogeneity of the condition.

Impact of antipsychotic medication on physical activity and physical fitness in adolescents: An exploratory study

Antipsychotics are used increasingly in adolescents for a range of psychiatric disorders. The aim of the current study was to investigate whether physical activity levels and physical fitness of adolescent inpatients treated with antipsychotic medication, differs from either (i) antipsychotic naïve adolescents with mental health problems and, (ii) healthy controls. All participants completed the Physical Activity Questionnaire for Adolescents, the Positive-and-Negative-Affect-Schedule and performed the Eurofit test battery. Adolescents with mental health problems (irrespective of antipsychotic medication) were significantly (P<0.05) less physically active and had an impaired whole body balance, running speed and cardiovascular endurance compared to healthy controls (n=15, 8♂, 15.9±1.3 years). Adolescents treated with antipsychotic medication (n=15, 8♂, 15.5±1.3 years) were less physically active and had an impaired whole body balance compared with antipsychotic naïve adolescents (n=15, 8♂, 15.7±1.4 years). Given the overwhelming deleterious impact of physical inactivity and low physical fitness on physical and mental health outcomes, interventions specifically targeting physical activity and physical fitness among adolescents experiencing mental illness, both treated with, and not treated with antipsychotic medication are warranted as a priority. Antipsychotic medication should be considered as a risk factor for physical inactivity and poor physical fitness.

Head-to-Head Comparison of Aripiprazole and Risperidone in the Treatment of ADHD Symptoms in Children with Autistic Spectrum Disorder and ADHD: A Pilot, Open-Label, Randomized Controlled Study

BACKGROUND

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are frequently overlapping neurodevelopmental disorders. Individuals in whom the disorders are comorbid show more severe impairment because of deficits in the processing of social situations, adaptive functioning, and executive control than individuals with either disorder alone.

OBJECTIVE

This open-label pilot study aimed to evaluate and compare the efficacy and tolerability of risperidone and aripiprazole for treating ADHD symptoms in patients with both ASD and ADHD over the course of 24 weeks of treatment.

METHODS

Patients (n = 44) were randomly assigned to start treatment with risperidone (22 patients) or aripiprazole (22 patients). Children were evaluated before starting treatment (T0), and after 12 weeks (T1) and 24 weeks (T2) of treatment. At each visit, specific psychiatric clinical scales were administered to assess the efficacy of the two drugs.

RESULTS

The mean age was 8.4 ± 2.9 years in the aripiprazole group and 7.8 ± 2.3 years in the risperidone group. A total of 37 children (29 boys and 8 girls) completed the study (18 in the aripiprazole group and 19 in the risperidone group). Aripiprazole and risperidone appeared to have similar benefits in terms of efficacy and tolerability, although there were slight differences between the two drugs. Both groups showed a significant improvement in ADHD symptoms after 24 weeks of treatment (ADHD Rating Scale, Conners Parent Rating Scale-Hyperactivity, and Clinical Global Improvement-Severity Scale). No significant difference between the two drugs on any parameters at 24 weeks were found. Prolactin levels were decreased in the aripiprazole group. Both drugs were well tolerated, with no serious adverse events detected.

CONCLUSIONS

Our study confirms the efficacy of both aripiprazole and risperidone in ameliorating ADHD symptoms of children also presenting with ASD.

Aripiprazole for treating irritability in children & adolescents with autism: A systematic review

BACKGROUND & OBJECTIVES

No clear therapeutic benefits of antipsychotics have been reported for the treatment of behavioural symptoms in autism. This systematic review provides an assessment of evidence for treating irritability in autism by aripiprazole.

METHODS

The databases of MEDLINE/PubMed and Google Scholar were searched for relevant articles about the effect of aripiprazole in children with autism. The articles were searched according to the inclusion and exclusion criteria specifed for this review. All the double-blind, controlled, randomized, clinical trials examining the efficacy of aripiprazole for treating children and adolescents with autism were included.

RESULTS

From the 93 titles identified, 26 were irrelevant and 58 were evaluated for more details. Only five articles met the inclusive criteria. The evidence from precise randomized double blind clinical trials of aripiprazole for the treatment of autism in children and adolescents was convincing enough to recommend aripiprazole. Adverse effects were not very common and were usually mild.

INTERPRETATION & CONCLUSIONS

Current evidence suggests that aripiprazole is as effective and safe as risperidone for treating irritability in autism. However, further studies with larger sample size and longer duration are required.

Assessment and Treatment of Anxiety in Youth With Autism Spectrum Disorders

OBJECTIVES

Anxiety is one of the most prevalent co-occurring symptoms in youth with autism spectrum disorder (ASD). The assessment and treatment recommendations proposed here are intended to help primary care providers with the assessment and treatment of anxiety in ASD.

METHODS

The Autism Speaks Autism Treatment Network/Autism Intervention Research on Physical Health Anxiety Workgroup, a multidisciplinary team of clinicians and researchers with expertise in ASD, developed the clinical recommendations. The recommendations were based on available scientific evidence regarding anxiety treatments, both in youth with ASD and typically developing youth, and clinical consensus of the workgroup where data were lacking.

RESULTS

Assessment of anxiety requires a systematic approach to evaluating symptoms and potential contributing factors across various developmental levels. Treatment recommendations include psychoeducation, coordination of care, and modified cognitive-behavioral therapy, particularly for children and adolescents with high-functioning ASD. Due to the limited evidence base in ASD, medications for anxiety should be prescribed cautiously with close monitoring of potential benefits and side effects.

CONCLUSIONS

Assessment and treatment of clinical anxiety in youth with ASD require a standardized approach to improve outcomes for youth with ASD. Although this approach provides a framework for clinicians, clinical judgment is recommended when making decisions about individual patients.

3p22.1p21.31 microdeletion identifies CCK as Asperger syndrome candidate gene and shows the way for therapeutic strategies in chromosome imbalances

Background

In contrast to other autism spectrum disorders, chromosome abnormalities are rare in Asperger syndrome (AS) or high-functioning autism. Consequently, AS was occasionally subjected to classical positional cloning. Here, we report on a case of AS associated with a deletion of the short arm of chromosome 3. Further in silico analysis has identified a candidate gene for AS and has suggested a therapeutic strategy for manifestations of the chromosome rearrangement.

Results

Using array comparative genomic hybridization, an interstitial deletion of 3p22.1p21.31 (~2.5 Mb in size) in a child with Asperger’s syndrome, seborrheic dermatitis and chronic pancreatitis was detected. Original bioinformatic approach to the prioritization of candidate genes/processes identified CCK (cholecystokinin) as a candidate gene for AS. In addition to processes associated with deleted genes, bioinformatic analysis of CCK gene interactome indicated that zinc deficiency might be a pathogenic mechanism in this case. This suggestion was supported by plasma zinc concentration measurements. The increase of zinc intake produced a rise in zinc plasma concentration and the improvement in the patient’s condition.

Conclusions

Our study supported previous linkage findings and had suggested a new candidate gene in AS. Moreover, bioinformatic analysis identified the pathogenic mechanism, which was used to propose a therapeutic strategy for manifestations of the deletion. The relative success of this strategy allows speculating that therapeutic or dietary normalization of metabolic processes altered by a chromosome imbalance or genomic copy number variations may be a way for treating at least a small proportion of cases of these presumably incurable genetic conditions.

Unmet needs in paediatric psychopharmacology: Present scenario and future perspectives

Paediatric psychopharmacology holds great promise in two equally important areas of enormous biomedical and social impact, namely the treatment of behavioural abnormalities in children and adolescents, and the prevention of psychiatric disorders with adolescent- or adult-onset. Yet, in striking contrast, pharmacological treatment options presently available in child and adolescent psychiatry are dramatically limited. The most important currently unmet needs in paediatric psychopharmacology are: the frequent off-label prescription of medications to children and adolescents based exclusively on data from randomized controlled studies involving adult patients; the frequent lack of age-specific dose, long-term efficacy and tolerability/safety data; the lack of effective medications for many paediatric psychiatric disorders, most critically autism spectrum disorder; the scarcity and limitations of randomized placebo-controlled trials in paediatric psychopharmacology; the unexplored potential for the prevention of psychiatric disorders with adolescent- and adult-onset; the current lack of biomarkers to predict treatment response and severe adverse effects; the need for better preclinical data to foster the successful development of novel drug therapies; and the effective dissemination of evidence-based treatments to the general public, to better inform patients and families of the benefits and risks of pharmacological interventions during development. Priorities and strategies are proposed to overcome some of these limitations, including the European Child and Adolescent Clinical Psychopharmacology Network, as an overarching Pan-European infrastructure aimed at reliably carrying out much needed psychopharmacological trials in children and adolescents, in order to fill the identified gaps and improve overall outcomes.

Acute dietary tryptophan manipulation differentially alters social behavior, brain serotonin and plasma corticosterone in three inbred mouse strains

Clinical evidence indicates brain serotonin (5-HT) stores and neurotransmission may be inadequate in subpopulations of individuals with autism, and this may contribute to characteristically impaired social behaviors. Findings that depletion of the 5-HT precursor tryptophan (TRP) worsens autism symptoms support this hypothesis. Yet dietetic studies show and parents report that many children with autism consume less TRP than peers. To measure the impact of dietary TRP content on social behavior, we administered either diets devoid of TRP, with standard TRP (0.2 g%), or with 1% added TRP (1.2 g%) overnight to three mouse strains. Of these, BTBRT(+)Itpr3(tf)/J and 129S1/SvImJ consistently exhibit low preference for social interaction relative to C57BL/6. We found that TRP depletion reduced C57BL/6 and 129S social interaction preference, while TRP enhancement improved BTBR sociability (p < 0.05; N = 8-10). Subsequent marble burying did not differ among diets or strains. After behavior tests, brain TRP levels and plasma corticosterone were higher in TRP enhanced C57BL/6 and BTBR, while 5-HT levels were reduced in all strains by TRP depletion (p < 0.05; N = 4-10). Relative hyperactivity of BTBR and hypoactivity of 129S, evident in self-grooming and chamber entries during sociability tests, were uninfluenced by dietary TRP. Our findings demonstrate mouse sociability and brain 5-HT turnover are reduced by acute TRP depletion, and can be enhanced by TRP supplementation. This outcome warrants further basic and clinical studies employing biomarker combinations such as TRP metabolism and 5-HT regulated hormones to characterize conditions wherein TRP supplementation may best ameliorate sociability deficits.

Toward an immune-mediated subtype of autism spectrum disorder

A role for immunological involvement in autism spectrum disorder (ASD) has long been hypothesized. This review includes four sections describing (1) evidence for a relationship between familial autoimmune disorders and ASD; (2) results from post-mortem and neuroimaging studies that investigated aspects of neuroinflammation in ASD; (3) findings from animal model work in ASD involving inflammatory processes; and (4) outcomes from trials of anti-inflammatory/immune-modulating drugs in ASD that have appeared in the literature. Following each section, ideas are provided for future research, suggesting paths forward in the continuing effort to define the role of immune factors and inflammation in the pathophysiology of a subtype of ASD. This article is part of a Special Issue entitled SI: Neuroimmunology in Health And Disease.

Clinical and pharmacokinetic evaluation of risperidone for the management of autism spectrum disorder

INTRODUCTION

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is often accompanied by psychiatric comorbidity. Although there is no medication currently available to treat the core symptoms of ASD, risperidone was the first drug to be approved for use in ASD and is still the best established psychopharmacological option for the treatment of irritability and behavioral problems in ASD.

AREAS COVERED

This article gives an overview of the pharmacokinetic profile of risperidone and a comprehensive review of treatment studies regarding the use of risperidone in ASD.

EXPERT OPINION

Ample evidence supports the short-term use of risperidone for treating irritability and behavioral problems in ASD. Risperidone also shows promise in treating symptoms often associated with ASD, such as stereotypical behavior, social difficulties, hyperactivity and cognitive problems. However, several adverse effects have been identified; most are mild or moderate and well manageable, but weight gain and metabolic changes are a considerable concern. Therefore, risperidone should in our view be seen as 'a last resort', only justified for the short-term treatment of serious behavioral problems, which have failed to respond sufficiently to behavioral interventions. Future studies should investigate long-term effects of risperidone and factors that facilitate individual risk-benefit analyses before treatment.