Effect of fluoxetine on regional cerebral metabolism in autistic spectrum disorders: a pilot study

Contribution of the serotonergic system to developmental brain abnormalities in autism spectrum disorder

This review highlights a key role of the serotonergic system in brain development and in distortions of normal brain development in early stages of fetal life resulting in cascades of abnormalities, including defects of neurogenesis, neuronal migration, neuronal growth, differentiation, and arborization, as well as defective neuronal circuit formation in the cortex, subcortical structures, brainstem, and cerebellum of autistic subjects. In autism, defects in regulation of neuronal growth are the most frequent and ubiquitous developmental changes associated with impaired neuron differentiation, smaller size, distorted shape, loss of spatial orientation, and distortion of cortex organization. Common developmental defects of the brain in autism include multiregional focal dysplastic changes contributing to local neuronal circuit distortion, epileptogenic activity, and epilepsy. There is a discrepancy between more than 500 reports demonstrating the contribution of the serotonergic system to autism's behavioral anomalies, highlighted by lack of studies of autistic subjects' brainstem raphe nuclei, the center of brain serotonergic innervation, and of the contribution of the serotonergic system to the diagnostic features of autism spectrum disorder (ASD). Discovery of severe fetal brainstem auditory system neuronal deficits and other anomalies leading to a spectrum of hearing deficits contributing to a cascade of behavioral alterations, including deficits of social and verbal communication in individuals with autism, is another argument to intensify postmortem studies of the type and topography of, and the severity of developmental defects in raphe nuclei and their contribution to abnormal brain development and to the broad spectrum of functional deficits and comorbid conditions in ASD.

Sertraline for anxiety in adults with a diagnosis of autism (STRATA): study protocol for a pragmatic, multicentre, double-blind, placebo-controlled randomised controlled trial

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed to manage anxiety in adults with an autism diagnosis. However, their effectiveness and adverse effect profile in the autistic population are not well known. This trial aims to determine the effectiveness and cost-effectiveness of the SSRI sertraline in reducing symptoms of anxiety and improving quality of life in adults with a diagnosis of autism compared with placebo and to quantify any adverse effects.

METHODS

STRATA is a two-parallel group, multi-centre, pragmatic, double-blind, randomised placebo-controlled trial with allocation at the level of the individual. It will be delivered through recruiting sites with autism services in 4 regional centres in the United Kingdom (UK) and 1 in Australia. Adults with an autism diagnosis and a Generalised Anxiety Disorder Assessment (GAD-7) score ≥ 10 at screening will be randomised 1:1 to either 25 mg sertraline or placebo, with subsequent flexible dose titration up to 200 mg. The primary outcome is GAD-7 scores at 16 weeks post-randomisation. Secondary outcomes include adverse effects, proportionate change in GAD-7 scores including 50% reduction, social anxiety, obsessive-compulsive symptoms, panic attacks, repetitive behaviours, meltdowns, depressive symptoms, composite depression and anxiety, functioning and disability and quality of life. Carer burden will be assessed in a linked carer sub-study. Outcome data will be collected using online/paper methods via video call, face-to-face or telephone according to participant preference at 16, 24 and 52 weeks post-randomisation, with brief safety checks and data collection at 1-2, 4, 8, 12 and 36 weeks. An economic evaluation to study the cost-effectiveness of sertraline vs placebo and a QuinteT Recruitment Intervention (QRI) to optimise recruitment and informed consent are embedded within the trial. Qualitative interviews at various times during the study will explore experiences of participating and taking the trial medication.

DISCUSSION

Results from this study should help autistic adults and their clinicians make evidence-based decisions on the use of sertraline for managing anxiety in this population.

TRIAL REGISTRATION

ISRCTN, ISRCTN15984604 . Registered on 08 February 2021. EudraCT 2019-004312-66. ANZCTR ACTRN12621000801819. Registered on 07 April 2021.

Citalopram Did Not Significantly Improve Anxiety in Children with Autism Spectrum Disorder Undergoing Treatment for Core Symptoms: Secondary Analysis of a Trial to Reduce Repetitive Behaviors

Objective: Anxiety disorders are among the most common co-occurring conditions in autism spectrum disorder (ASD). Despite their prevalence and impact, there are no randomized controlled trials (RCTs) aimed at evaluating the efficacy of selective serotonin reuptake inhibitors (SSRIs) for anxiolysis in this population, who may have a different biological basis for anxiety. Methods: Secondary analyses of the STAART double-blind, placebo-controlled RCT of citalopram in children with ASD examined whether citalopram reduced anxiety measured on the parent-reported Child and Adolescent Symptom Inventory-4 (CASI-4) as the primary outcome. An intention-to-treat analysis involving all 149 participants used multiple imputations for missing data and included baseline stratification factors of age group and site, among others. We prespecified as clinically significant a 33% reduction in anxiety in citalopram versus placebo, coinciding with 80% power. We tested whether communicative ability on the Vineland Communication score moderated treatment effect and explored whether initial anxiety was associated with greater adverse events, which could impact on dose titration and achieving optimal dose. Results: Both groups showed substantial reduction in anxiety. Citalopram was associated with a nonsignificant 16.5% greater reduction (observed coefficient = -0.181, bootstrap standard error = 0.126, p = 0.151, confidence interval = -0.428 to 0.066). Anxiety reports were significantly lower in children with reduced communicative ability, but communicative ability did not moderate the treatment effect (interaction p = 0.294). Initial anxiety levels were not associated with increased adverse effects (interaction ps 0.162-0.954). Conclusion: Citalopram did not statistically significantly improve anxiety in children with ASD. Clinicians should be cautious in their use of SSRIs for this indication. There remains a need for well-powered clinical trials testing the efficacy of SSRIs among autistic children with anxiety disorders.

Positron Emission Tomography in the Neuroimaging of Autism Spectrum Disorder: A Review

Autism spectrum disorder (ASD) is a basket term for neurodevelopmental disorders characterized by marked impairments in social interactions, repetitive and stereotypical behaviors, and restricted interests and activities. Subtypes include (A) disorders with known genetic abnormalities including fragile X syndrome, Rett syndrome, and tuberous sclerosis and (B) idiopathic ASD, conditions with unknown etiologies. Positron emission tomography (PET) is a molecular imaging technology that can be utilized in vivo for dynamic and quantitative research, and is a valuable tool for exploring pathophysiological mechanisms, evaluating therapeutic efficacy, and accelerating drug development in ASD. Recently, several imaging studies on ASD have been published and physiological changes during ASD progression was disclosed by PET. This paper reviews the specific radioligands for PET imaging of critical biomarkers in ASD, and summarizes and discusses the similar and different discoveries in outcomes of previous studies. It is of great importance to identify general physiological changes in cerebral glucose metabolism, cerebral blood flow perfusion, abnormalities in neurotransmitter systems, and inflammation in the central nervous system in ASD, which may provide excellent points for further ASD research.

The psychopharmacology algorithm project at the Harvard South Shore Program: An algorithm for core symptoms of autism spectrum disorder in adults

Autism spectrum disorder (ASD) is characterized by impaired social communication and restricted repetitive behaviors and interests. There are no FDA-approved medications for these core symptoms, and there are limited data regarding pharmacological management of ASD in adults. Here, the literature was reviewed in an effort to develop an algorithm for pharmacological management of core symptoms of ASD in adults. The literature search was conducted using PubMed. It was very difficult to distil a plausible algorithm from these data. Not included in this review are behavioral strategies, which are first-line. For instances when medication is being considered for management of core ASD symptoms in adults, the authors suggest starting with fluvoxamine as first-line, with possible consideration of a second SSRI trial if there is an inadequate or no response to fluvoxamine. The next step, if there is comorbid irritability, is to consider a second-generation antipsychotic. If there is no comorbid irritability, in the final step of the tentative algorithm, there are possible augmenting agents: propranolol, memantine, d-cycloserine, and oxytocin. Management of the symptoms of ASD requires a comprehensive treatment approach, and treatment planning must be individualized. Treatment of core ASD symptoms is not always desired. Further studies are needed to develop a stronger evidence base to support pharmacological management of core symptoms.

Anxiety Disorders in Adults with Autism Spectrum Disorder: A Population-Based Study

Anxiety is common in children with ASD; however, the burden of specific anxiety disorders for adults with ASD is under-researched. Using the Stockholm Youth Cohort, we compared anxiety disorder diagnoses among autistic adults (n = 4049), with or without intellectual disability, and population controls (n = 217,645). We conducted additional sibling analyses. Anxiety disorders were diagnosed in 20.1% of adults with ASD compared with 8.7% of controls (RR = 2.62 [95% CI 2.47–2.79]), with greatest risk for autistic people without intellectual disability. Rates of almost all individual anxiety disorders were raised, notably obsessive–compulsive disorder and phobic anxiety disorders. Anxiety disorders were more common in full siblings and half-siblings of people with ASD. The implications of this are explored.

Gender-Specific Effect of 5-HT and 5-HIAA on Threshold Level of Behavioral Symptoms and Sex-Bias in Prevalence of Autism Spectrum Disorder

Platelet hyperserotonemia in a subset of Autism Spectrum Disorder (ASD) probands, efficacy of selective serotonin reuptake inhibitors (SSRIs) in reducing behavioral deficits and gender-bias in normal serotonin (5-hydroxy tryptamine or 5-HT) synthesis suggest disruption in stringent regulation of serotonin metabolism in ASD. Therefore, we investigated the changes in 5-HT and 5-hydroxy indole acetic acid (5-HIAA) in ASD probands to assess its effect on the behavior of male and female probands. ASD cases (n = 215) were examined using childhood autism rating scale (CARS). Platelet 5-HT (104 cases and 26 controls) and platelet/plasma 5-HIAA (73 cases and 17 controls) were estimated using high performance liquid chromatography coupled with electrochemical detector (HPLC-ECD). In male probands, we observed increase in platelet 5-HT content in association with increase in the score for adaptive responses and increase in platelet 5-HIAA levels with concomitant decline in the score for intellectual response. Age did not influence the neurochemical parameters, but imitation, listening responses and nonverbal communication scores decreased with age. Conversely in female probands, plasma 5-HIAA level significantly attenuated with age, when platelet 5-HT content remained unchanged. Interestingly, platelet/plasma 5-HT and plasma 5-HIAA were higher in female controls. Female probands displayed severe autism-associated behaviors. Overall results indicate gender-bias in 5-HT and 5-HIAA regulation, which probably increases the threshold level of ASD phenotypes in the females, thereby affecting ASD prevalence in a sex-specific manner.

Modulation of brain activation during executive functioning in autism with citalopram

Adults with autism spectrum disorder (ASD) are frequently prescribed selective serotonin reuptake inhibitors (SSRIs). However, there is limited evidence to support this practice. Therefore, it is crucial to understand the impact of SSRIs on brain function abnormalities in ASD. It has been suggested that some core symptoms in ASD are underpinned by deficits in executive functioning (EF). Hence, we investigated the role of the SSRI citalopram on EF networks in 19 right-handed adult males with ASD and 19 controls who did not differ in gender, age, IQ or handedness. We performed pharmacological functional magnetic resonance imaging to compare brain activity during two EF tasks (of response inhibition and sustained attention) after an acute dose of 20 mg citalopram or placebo using a randomised, double-blind, crossover design. Under placebo condition, individuals with ASD had abnormal brain activation in response inhibition regions, including inferior frontal, precentral and postcentral cortices and cerebellum. During sustained attention, individuals with ASD had abnormal brain activation in middle temporal cortex and (pre)cuneus. After citalopram administration, abnormal brain activation in inferior frontal cortex was 'normalised' and most of the other brain functional differences were 'abolished'. Also, within ASD, the degree of responsivity in inferior frontal and postcentral cortices to SSRI challenge was related to plasma serotonin levels. These findings suggest that citalopram can 'normalise' atypical brain activation during EF in ASD. Future trials should investigate whether this shift in the biology of ASD is maintained after prolonged citalopram treatment, and if peripheral measures of serotonin predict treatment response.

Effect of Fluoxetine on Obsessive-Compulsive Behaviors in Children and Adolescents With Autism Spectrum Disorders: A Randomized Clinical Trial

IMPORTANCE

Selective serotonin receptor inhibitors are prescribed to reduce the severity of core behaviors of autism spectrum disorders, but their efficacy remains uncertain.

OBJECTIVE

To determine the efficacy of fluoxetine for reducing the frequency and severity of obsessive-compulsive behaviors in autism spectrum disorders.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, randomized, placebo-controlled clinical trial. Participants aged 7.5-18 years with autism spectrum disorders and a total score of 6 or higher on the Children's Yale-Brown Obsessive Compulsive Scale, modified for pervasive developmental disorder (CYBOCS-PDD) were recruited from 3 tertiary health centers across Australia. Enrollment began November 2010 and ended April 2017. Follow-up ended August 2017.

INTERVENTIONS

Participants were randomized to receive fluoxetine (n = 75) or placebo (n = 71). Study medication was commenced at 4 or 8 mg/d for the first week, depending on weight, and then titrated to a maximum dose of 20 or 30 mg/d over 4 weeks. Treatment duration was 16 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcome was the total score on the CYBOCS-PDD (scores range from 0-20; higher scores indicate higher levels of maladaptive behaviors; minimal clinically important difference, 2 points) at 16 weeks postrandomization, analyzed with a linear regression model adjusted for stratification factors (site, age at baseline, and intellectual disability), with an additional prespecified model that included additional adjustment for baseline score, sex, communication level, and imbalanced baseline and demographic variables.

RESULTS

Among the 146 participants who were randomized (85% males; mean age, 11.2 years), 109 completed the trial; 31 in the fluoxetine group and 21 in the placebo group dropped out or did not complete treatment. The mean CYBOCS-PDD score from baseline to 16 weeks decreased in the fluoxetine group from 12.80 to 9.02 points (3.72-point decrease; 95% CI, -4.85 to -2.60) and in the placebo group from 13.13 to 10.89 points (2.53-point decrease; 95% CI, -3.86 to -1.19). The between-group mean difference at 16 weeks was -2.01 (95% CI, -3.77 to -0.25; P = .03) (adjusted for stratification factors), and in the prespecified model with further adjustment, it was -1.17 (95% CI, -3.01 to 0.67; P = .21).

CONCLUSIONS AND RELEVANCE

In this preliminary study of children and adolescents with autism spectrum disorders, treatment with fluoxetine compared with placebo resulted in significantly lower scores for obsessive-compulsive behaviors at 16 weeks. Interpretation is limited by the high dropout rate, null findings of prespecified analyses that accounted for potentially confounding factors and baseline imbalances, and CIs for the treatment effect that included the minimal clinically important difference.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12608000173392.

CRISPR/Cas9-mediated disruption of SHANK3 in monkey leads to drug-treatable autism-like symptoms

Monogenic mutations in the SHANK3 gene, which encodes a postsynaptic scaffold protein, play a causative role in autism spectrum disorder (ASD). Although a number of mouse models with Shank3 mutations have been valuable for investigating the pathogenesis of ASD, species-dependent differences in behaviors and brain structures post considerable challenges to use small animals to model ASD and to translate experimental therapeutics to the clinic. We have used clustered regularly interspersed short palindromic repeat/CRISPR-associated nuclease 9 to generate a cynomolgus monkey model by disrupting SHANK3 at exons 6 and 12. Analysis of the live mutant monkey revealed the core behavioral abnormalities of ASD, including impaired social interaction and repetitive behaviors, and reduced brain network activities detected by positron-emission computed tomography (PET). Importantly, these abnormal behaviors and brain activities were alleviated by the antidepressant fluoxetine treatment. Our findings provide the first demonstration that the genetically modified non-human primate can be used for translational research of therapeutics for ASD.

Citalopram attenuates social behavior deficits in the BTBR T+Itpr3tf/J mouse model of autism

Autism spectrum disorder (ASD) is diagnosed by two core symptoms: impaired social communication and the presence of repetitive, stereotyped behaviors and/or restricted interests. Alterations in serotonergic signaling are involved in the genesis of ASD. Selective serotonin reuptake inhibitors (SSRIs) have been reported to reduce repetitive behaviors and rescue social deficits in ASD mouse models and patients. In the present study, we examined the potential of citalopram (a representative selective serotonin reuptake inhibitor) on sociability and repetitive behaviors in the BTBR T⁺Itpr3^tf/J (BTBR) mouse model of ASD. We found that the deficits of sociability in the BTBR mice were reversed by a 20 mg/kg dose of citalopram treatment without any adverse effects on locomotor activity or anxiety level. In addition, both high (20 mg/kg) and low (10 mg/kg) doses decreased the repetitive behavior of marble burying but did not affect self-grooming behavior. Furthermore, both doses were shown to have antidepressant-like activity in both the B6 and the BTBR mice in the tail suspension test. Taken together, these findings further demonstrate that citalopram can alleviate behavioral abnormalities in the BTBR autism model and lend support to the hypothesis that SSRIs may be potential therapeutic drugs for the treatment of behavioral dysfunctions in ASD.

Autism Spectrum Disorder: Classification, diagnosis and therapy

Autism Spectrum Disorder (ASD) refers to a group of neurodevelopmental disorders including autism, Asperger's syndrome (AS) and pervasive developmental disorder-not otherwise specified (PDD-NOS). The new diagnostic criteria of ASD focuses on two core domains: social communication impairment and restricted interests/repetitive behaviors. The prevalence of ASD has been steadily increasing over the past two decades, with current estimates reaching up to 1 in 36 children. Hereditary factors, parental history of psychiatric disorders, pre-term births, and fetal exposure to psychotropic drugs or insecticides have all been linked to higher risk of ASD. Several scales such as the Childhood Autism Rating Scale (CARS), The Autism Spectrum Disorder-Observation for Children (ASD-OC), The Developmental, Dimensional, and Diagnostic Interview (3di), are available to aid in better assessing the behaviors and symptoms associated with ASD. Nearly 75% of ASD patients suffer from comorbid psychiatric illnesses or conditions, which may include attention-deficit hyperactivity disorder (ADHD), anxiety, bipolar disorder, depression, Tourette syndrome, and others. Both pharmacological and non-pharmacological interventions are available for ASD. Pharmacological treatments include psychostimulants, atypical antipsychotics, antidepressants, and alpha-2 adrenergic receptor agonists. These medications provide partial symptomatic relief of core symptoms of ASD or manage the symptoms of comorbid conditions. Non-pharmacological interventions, which show promising evidence in improving social interaction and verbal communication of ASD patients, include music therapy, cognitive behavioral therapy and social behavioral therapy. Hormonal therapies with oxytocyin or vasopressin receptor antagonists have also shown some promise in improving core ASD symptoms. The use of vitamins, herbal remedies and nutritional supplements in conjunction with pharmacological and behavioral treatment appear to have some effect in symptomatic improvement in ASD, though additional studies are needed to confirm these benefits. Developing novel disease-modifying therapies may prove to be the ultimate intervention for sustained improvement of symptoms in ASD.

Measurement properties of tools used to assess depression in adults with and without autism spectrum conditions: A systematic review

Depression is the most commonly experienced mental health condition in adults with autism spectrum conditions (ASC). However, it is unclear what tools are currently being used to assess depression in ASC, or whether tools need to be adapted for this group. This systematic review therefore aimed to identify tools used to assess depression in adults with and without ASC, and then evaluate these tools for their appropriateness and measurement properties. Medline, PsychINFO and Web of Knowledge were searched for studies of depression in: (a) adults with ASC, without co‐morbid intellectual disability; and (b) adults from the general population without co‐morbid conditions. Articles examining the measurement properties of these tools were then searched for using a methodological filter in PubMed, and the quality of the evidence was evaluated using the COSMIN checklist. Twelve articles were identified which utilized three tools to assess depression in adults with ASC, but only one article which assessed the measurement properties of one of these tools was identified and thus evaluated. Sixty‐four articles were identified which utilized five tools to assess depression in general population adults, and fourteen articles had assessed the measurement properties of these tools. Overall, two tools were found to be robust in their measurement properties in the general population—the Beck Depression Inventory (BDI‐II), and the patient health questionnaire (PHQ‐9). Crucially only one study was identified from the COSMIN search, which showed weak evidence in support of the measurement properties of the BDI‐II in an ASC sample. Implications for effective measurement of depression in ASC are discussed. Autism Res2018, 11: 738–754. © 2018 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc.

Lay Summary

Depression is the most common mental health problem experienced by adults with autism. However, the current study found very limited evidence regarding how useful tools developed for the general population are for adults with autism. We therefore suggest how these tools could be adapted to more effectively assess depression in adults with autism, and improve these individuals access to mental health assessment and support.

Pharmacological management of core and comorbid symptoms in autism-spectrum disorder

In this article we review the evidence base and practical experience supporting the use of psychopharmacological treatments for autism-spectrum disorders across the lifespan. Recent advances in knowledge are highlighted, as are the shortcomings of published data in this field. Psychosocial and educational interventions remain the core of treatment, but there is now evidence that medication management is a good option for certain domains of behaviour. We discuss the evidence in terms of symptom clusters, including the underlying social deficit of autism and common psychiatric comorbidities.

Autism spectrum disorder: Consensus guidelines on assessment, treatment and research from the British Association for Psychopharmacology

An expert review of the aetiology, assessment, and treatment of autism spectrum disorder, and recommendations for diagnosis, management and service provision was coordinated by the British Association for Psychopharmacology, and evidence graded. The aetiology of autism spectrum disorder involves genetic and environmental contributions, and implicates a number of brain systems, in particular the gamma-aminobutyric acid, serotonergic and glutamatergic systems. The presentation of autism spectrum disorder varies widely and co-occurring health problems (in particular epilepsy, sleep disorders, anxiety, depression, attention deficit/hyperactivity disorder and irritability) are common. We did not recommend the routine use of any pharmacological treatment for the core symptoms of autism spectrum disorder. In children, melatonin may be useful to treat sleep problems, dopamine blockers for irritability, and methylphenidate, atomoxetine and guanfacine for attention deficit/hyperactivity disorder. The evidence for use of medication in adults is limited and recommendations are largely based on extrapolations from studies in children and patients without autism spectrum disorder. We discuss the conditions for considering and evaluating a trial of medication treatment, when non-pharmacological interventions should be considered, and make recommendations on service delivery. Finally, we identify key gaps and limitations in the current evidence base and make recommendations for future research and the design of clinical trials.

Psychopharmacological interventions in autism spectrum disorder

INTRODUCTION

Individuals with autism spectrum disorder (ASD) commonly present for treatment of emotional and behavioral disturbances associated with ASD's "core" symptoms. Psychotropic medications are widely utilized in alleviating associated emotional and behavioral symptoms.

AREAS COVERED

Emotional and behavioral disturbances associated with ASD include irritability/severely disruptive behavior, which comprises the heaviest symptom burden; hyperactivity and other Attention-Deficit-Hyperactivity-Disorder (ADHD)-type symptoms; repetitive/stereotyped behaviors; and social withdrawal. Existing evidence for medications for each of these symptom clusters will be examined in this review.

EXPERT OPINION

Psychopharmacological treatment of core and associated symptoms in ASD is challenging, in large part because of the heterogeneity in the presentation of ASD. Furthermore, children and adolescents with ASD are more vulnerable to the side effects of psychopharmacological intervention than their age-matched, typically developing counterparts. Currently, risperidone and aripiprazole are the only medications that have been (relatively) reliably shown to help treat certain symptom clusters associated with ASD, namely severely disruptive behavior and hyperactivity. Recent studies have begun to look at medications with mechanisms that are novel in the treatment of ASD and that may address underlying pathophysiology and/or core symptoms such as glutamate-modulating agents. Overall, randomized, placebo-controlled studies of medications for the treatment of ASD are scarce.

Translational Mouse Models of Autism: Advancing Toward Pharmacological Therapeutics

Animal models provide preclinical tools to investigate the causal role of genetic mutations and environmental factors in the etiology of autism spectrum disorder (ASD). Knockout and humanized knock-in mice, and more recently knockout rats, have been generated for many of the de novo single gene mutations and copy number variants (CNVs) detected in ASD and comorbid neurodevelopmental disorders. Mouse models incorporating genetic and environmental manipulations have been employed for preclinical testing of hypothesis-driven pharmacological targets, to begin to develop treatments for the diagnostic and associated symptoms of autism. In this review, we summarize rodent behavioral assays relevant to the core features of autism, preclinical and clinical evaluations of pharmacological interventions, and strategies to improve the translational value of rodent models of autism.

Inverse Effect of Fluoxetine on Medial Prefrontal Cortex Activation During Reward Reversal in ADHD and Autism

Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) share brain function abnormalities during cognitive flexibility. Serotonin is involved in both disorders, and selective serotonin reuptake inhibitors (SSRIs) can modulate cognitive flexibility and improve behavior in both disorders. Thus, this study investigates shared and disorder-specific brain dysfunctions in these 2 disorders during reward reversal, and the acute effects of an SSRI on these. Age-matched boys with ADHD (15), ASD (18), and controls (21) were compared with functional magnetic resonance imaging (fMRI) during a reversal task. Patients were scanned twice, under either an acute dose of Fluoxetine or placebo in a double-blind, placebo-controlled randomized design. Repeated-measures analyses within patients assessed drug effects. Patients under each drug condition were compared with controls to assess normalization effects. fMRI data showed that, under placebo, ASD boys underactivated medial prefrontal cortex (mPFC), compared with control and ADHD boys. Both patient groups shared decreased precuneus activation. Under Fluoxetine, mPFC activation was up-regulated and normalized in ASD boys relative to controls, but down-regulated in ADHD boys relative to placebo, which was concomitant with worse task performance in ADHD. Fluoxetine therefore has inverse effects on mPFC activation in ASD and ADHD during reversal learning, suggesting dissociated underlying serotonin abnormalities.

Outcome measures in intervention trials for adults with autism spectrum disorders; a systematic review of assessments of core autism features and associated emotional and behavioural problems

A systematic review was conducted of outcome measures used in treatment trials for older adolescents and adults with autism spectrum disorders (ASDs). Of 818 titles only 30 articles (19 of which involved pharmacological treatments) were identified that met inclusion criteria (sample size > 5; mean age of group > 15 years; mean IQ > 30; ASD diagnosis confirmed; use of objective ASD outcome measures; focus on symptoms core to or typically associated with ASDs). Selected studies included randomized and placebo-controlled trials, retrospective assessment studies, case series and open label or case-control trials. Use of outcome measures varied with frequent use of non-standardized assessments, very little use of measures designed specifically for individuals with ASD or of instruments focusing on core ASD deficits, such as communication or social functioning. Most commonly used were the Clinical Global Impression (CGI) rating scale and the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The strengths or deficiencies of the outcome measures used were not systematically evaluated. Although there are now many well controlled treatment trials for children with ASDs, adult intervention research is very limited. The lack of valid and reliable outcome measures for adults with ASDs compromises attempts at treatment evaluation.

Disorder-dissociated effects of fluoxetine on brain function of working memory in attention deficit hyperactivity disorder and autism spectrum disorder

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are often co-morbid and share performance and brain dysfunctions during working memory (WM). Serotonin agonists modulate WM and there is evidence of positive behavioural effects in both disorders. We therefore used functional magnetic resonance imaging (fMRI) to investigate shared and disorder-specific brain dysfunctions of WM in these disorders, and the effects of a single dose of the selective serotonin reuptake inhibitor (SSRI) fluoxetine.

METHOD

Age-matched boys with ADHD (n = 17), ASD (n = 17) and controls (n = 22) were compared using fMRI during an N-back WM task. Patients were scanned twice, under either an acute dose of fluoxetine or placebo in a double-blind, placebo-controlled randomized design. Repeated-measures analyses within patients assessed drug effects on performance and brain function. To test for normalization effects of brain dysfunctions, patients under each drug condition were compared to controls.

RESULTS

Under placebo, relative to controls, both ADHD and ASD boys shared underactivation in the right dorsolateral prefrontal cortex (DLPFC). Fluoxetine significantly normalized the DLPFC underactivation in ASD relative to controls whereas it increased posterior cingulate cortex (PCC) deactivation in ADHD relative to control boys. Within-patient analyses showed inverse effects of fluoxetine on PCC deactivation, which it enhanced in ADHD and decreased in ASD.

CONCLUSIONS

The findings show that fluoxetine modulates brain activation during WM in a disorder-specific manner by normalizing task-positive DLPFC dysfunction in ASD boys and enhancing task-negative default mode network (DMN) deactivation in ADHD.

Pharmacogenomic medicine in autism: challenges and opportunities

Autism spectrum disorder (ASD) affects 1 in 68 children in the US and is distinguished by core deficits in social interactions. Developing pharmacologic treatments for ASD is complicated by clinical and genetic heterogeneity. Although pharmacological treatments have not been shown to be effective in treating the core symptoms of ASD (i.e., social deficits), there is evidence that the burden of emotional and behavioral problems can be reduced with pharmacotherapy. Numerous randomized clinical trials of treatments for the core ASD deficits have been conducted; however, most have provided inconclusive results due to the substantial variation in treatment response. Variation also exists in the considerable metabolic side effects of many of the current treatments. Some of this variation may be explained by differences in the underlying genetic pathways. Exploiting the link between genetic heterogeneity and clinical variation associated with behavioral problems may provide an opportunity for targeted treatment of ASD. In this review, we summarize the recent findings from pharmacogenomics studies of ASD and suggest further how understanding how genetic liability modifies the effect of drugs may present an opportunity to address the challenges of personalized medicine in autism.

A systematic review of molecular imaging (PET and SPECT) in autism spectrum disorder: current state and future research opportunities

Non-invasive positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are techniques used to quantify molecular interactions, biological processes and protein concentration and distribution. In the central nervous system, these molecular imaging techniques can provide critical insights into neurotransmitter receptors and their occupancy by neurotransmitters or drugs. In recent years, there has been an increase in the number of studies that have investigated neurotransmitters in autism spectrum disorder (ASD), while earlier studies mostly focused on cerebral blood flow and glucose metabolism. The underlying and contributing mechanisms of ASD are largely undetermined and ASD diagnosis relies on the behavioral phenotype. Discovery of biochemical endophenotypes would represent a milestone in autism research that could potentially lead to ASD subtype stratification and the development of novel therapeutic drugs. This review characterizes the prior use of molecular imaging by PET and SPECT in ASD, addresses methodological challenges and highlights areas of future opportunity for contributions from molecular imaging to understand ASD pathophysiology.

Distinctive behavioral and cellular responses to fluoxetine in the mouse model for Fragile X syndrome

Fluoxetine is used as a therapeutic agent for autism spectrum disorder (ASD), including Fragile X syndrome (FXS). The treatment often associates with disruptive behaviors such as agitation and disinhibited behaviors in FXS. To identify mechanisms that increase the risk to poor treatment outcome, we investigated the behavioral and cellular effects of fluoxetine on adult Fmr1 knockout (KO) mice, a mouse model for FXS. We found that fluoxetine reduced anxiety-like behavior of both wild-type and Fmr1 KO mice seen as shortened latency to enter the center area in the open field test. In Fmr1 KO mice, fluoxetine normalized locomotor hyperactivity but abnormally increased exploratory activity. Reduced brain-derived neurotrophic factor (BDNF) and increased TrkB receptor expression levels in the hippocampus of Fmr1 KO mice associated with inappropriate coping responses under stressful condition and abolished antidepressant activity of fluoxetine. Fluoxetine response in the cell proliferation was also missing in the hippocampus of Fmr1 KO mice when compared with wild-type controls. The postnatal mRNA expression of serotonin transporter (SERT) was reduced in the thalamic nuclei of Fmr1 KO mice during the time of transient innervation of somatosensory neurons suggesting that developmental changes of SERT expression were involved in the differential cellular and behavioral responses to fluoxetine in wild-type and Fmr1 mice. The results indicate that changes of BDNF/TrkB signaling contribute to differential behavioral responses to fluoxetine among individuals with ASD.

Psychopharmacological interventions in autism spectrum disorder

After participating in this educational activity, the physician should be better able to1. Prescribe the appropriate psychotropic medication to treat symptoms of ASD.2. Identify the side effects of the psychotropic medications used to treat ASD.Autism spectrum disorders (ASDs) are characterized by core deficits in social communication and language, and restrictive and repetitive behaviors that cause significant functional impairment and distress for affected individuals and their caregivers. The increasing prevalence of ASD, most recently estimated as 1 in 88 children, presents an ever-increasing burden on families, schools, medical systems, and society at large. Individuals with ASD commonly present for treatment of associated emotional and behavioral disturbances that include anxiety, symptoms of ADHD, compulsions and other repetitive behaviors, mood lability, irritability, aggression, and sleep disturbance. Psychotropic medications are widely utilized in alleviating these symptoms, though rigorous clinical trials in ASD are lacking for most areas of impairment. Strong evidence from randomized, placebo-controlled trials supports the use of atypical antipsychotics, particularly risperidone and aripiprazole, for managing severe irritability and aggression in ASD. Serotonin reuptake inhibitors are commonly used to treat anxiety and compulsions, though reports of efficacy in the literature are mixed, and behavioral side effects in children are common. Minimal evidence supports the utility of anticonvulsants and traditional mood stabilizers in managing mood lability and aggression. Stimulant and nonstimulant ADHD medications can be effective for reducing hyperactivity, inattention, and impulsivity, though to a lesser degree than in ADHD populations without ASD and with greater risk of adverse effects. Psychopharmacological interventions in development for core symptoms of autism include those that target the glutamatergic and GABAergic neurotransmitter systems and the neuropeptide oxytocin. Further research is needed to establish evidence-based interventions in ASD populations.

[Pharmacological treatments in patients with pervasive developmental disorders: A review]

BACKGROUND

Pervasive developmental disorders (PDD) are neurodevelepmental disorders that are characterized by severe deficits in socialisation and communication, and the existence of repetitive and stereotyped interests and behaviours. It is estimated more than 60/100,000 children are suffering from PDD. Comorbid disorders are common in people with PDD, including intellectual deficiency, symptoms of attention deficit-hyperactivity, aggression and disruption, and pervasive repetitive behaviours or thoughts. These symptoms have a negative impact on the outcome and quality of life of the patients and their caregivers. The first-line management of comorbid disorders in PDD is behavioural intervention, but sometimes this is not sufficient, and the use of pharmacological treatment is needed.

METHOD

We conducted a review of studies of medical treatments used in patients with PDD to establish which treatments show good evidence of efficacy in PDD. We used the Medline database and the following keywords "pervasive development disorders" or "autism spectrum disorders" or "autistic disorder" and "therapy" or "treatment".

RESULTS

The treatments that showed the best efficacy on irritability in well-designed studies are second generation antipsychotics, risperidone and aripiprazole. Some studies indicate that haloperidol is efficient as well, but the very high frequency of extra-pyramidal effects limits its use. Methylphenidate has shown some efficacy on impulsivity and hyperactivity in randomised placebo-controlled studies. First data concerning atomoxetine are promising but better-designed studies are needed. Selective serotonin re-uptake inhibitors: fluvoxamine and fluoxetine have shown some efficacy in the treatment of serious and pervasive repetitive behaviours. Alpha-adrenergic treatments, clonidine and guanfacine, can help in the management of disruptive behaviours in patients with PDD. Data concerning naltrexone are contradictory, indeed many case reports of its efficacy on aggressive (mostly auto-aggressive) behaviours are reported in the literature, but well-designed studies do not find any improvement in patients treated with naltrexone compared with patients treated with placebo. First data concerning ocytocin are promising, indeed, if they were to be confirmed, that would be the first treatment efficient on the core symptoms of PDD.

Selective serotonin reuptake inhibitors (SSRIs) for autism spectrum disorders (ASD)

BACKGROUND

Autism spectrum disorders (ASD) are characterised by abnormalities in social interaction and communication skills, as well as stereotypic behaviours and restricted activities and interests. Selective serotonin reuptake inhibitors (SSRIs) are prescribed for the treatment of conditions often comorbid with ASD such as depression, anxiety and obsessive-compulsive behaviours.

OBJECTIVES

To determine if treatment with an SSRI:1. improves the core features of autism (social interaction, communication and behavioural problems);2. improves other non-core aspects of behaviour or function such as self-injurious behaviour;3. improves the quality of life of adults or children and their carers;4. has short- and long-term effects on outcome;5. causes harm.

SEARCH METHODS

We searched the following databases up until March 2013: CENTRAL, Ovid MEDLINE, Embase, CINAHL, PsycINFO, ERIC and Sociological Abstracts. We also searched ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP). This was supplemented by searching reference lists and contacting known experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any dose of oral SSRI compared with placebo, in people with ASD.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, extracted data and appraised each study's risk of bias.

MAIN RESULTS

Nine RCTs with a total of 320 participants were included. Four SSRIs were evaluated: fluoxetine (three studies), fluvoxamine (two studies), fenfluramine (two studies) and citalopram (two studies). Five studies included only children and four studies included only adults. Varying inclusion criteria were used with regard to diagnostic criteria and intelligence quotient of participants. Eighteen different outcome measures were reported. Although more than one study reported data for Clinical Global Impression (CGI) and obsessive-compulsive behaviour (OCB), different tool types or components of these outcomes were used in each study. As such, data were unsuitable for meta-analysis, except for one outcome (proportion improvement). One large, high-quality study in children showed no evidence of positive effect of citalopram. Three small studies in adults showed positive outcomes for CGI and OCB; one study showed improvements in aggression, and another in anxiety.

AUTHORS' CONCLUSIONS

There is no evidence of effect of SSRIs in children and emerging evidence of harm. There is limited evidence of the effectiveness of SSRIs in adults from small studies in which risk of bias is unclear.

Psychopharmacology of autism spectrum disorders: a selective review

While there is no cure for autism spectrum disorder, psychopharmacologic agents are often used with behavioral and educational approaches to treat its comorbid symptoms of hyperactivity, irritability, and aggression. Studies suggest that at least 50% of persons with autism spectrum disorder receive psychotropic medications during their life span. This selective review examines recent studies about the use of psychotropic medications in persons with autism spectrum disorder. The aim was to focus on randomized controlled trials conducted from 1990 to 2010 on this topic. A comprehensive literature search was performed using PubMed and Cochrane databases. Out of 105 studies identified for the review, only 24 were randomized controlled trials. Thus, despite the common use of these medications in autism spectrum disorder, more controlled studies are needed to determine their long-term efficacy and safety.

Reward circuitry dysfunction in psychiatric and neurodevelopmental disorders and genetic syndromes: animal models and clinical findings

This review summarizes evidence of dysregulated reward circuitry function in a range of neurodevelopmental and psychiatric disorders and genetic syndromes. First, the contribution of identifying a core mechanistic process across disparate disorders to disease classification is discussed, followed by a review of the neurobiology of reward circuitry. We next consider preclinical animal models and clinical evidence of reward-pathway dysfunction in a range of disorders, including psychiatric disorders (i.e., substance-use disorders, affective disorders, eating disorders, and obsessive compulsive disorders), neurodevelopmental disorders (i.e., schizophrenia, attention-deficit/hyperactivity disorder, autism spectrum disorders, Tourette's syndrome, conduct disorder/oppositional defiant disorder), and genetic syndromes (i.e., Fragile X syndrome, Prader-Willi syndrome, Williams syndrome, Angelman syndrome, and Rett syndrome). We also provide brief overviews of effective psychopharmacologic agents that have an effect on the dopamine system in these disorders. This review concludes with methodological considerations for future research designed to more clearly probe reward-circuitry dysfunction, with the ultimate goal of improved intervention strategies.

The effects of antidepressants on human brain as detected by imaging studies. Focus on major depression

Recent brain imaging studies have shed light on understanding the pathogenesis of mood disorders. Evidence of structural, chemical, and functional brain changes, particularly in prefrontal cortex, cingulate, and amygdala, has been revealed in major depressive disorder (MDD). Furthermore, imaging techniques have been applied to monitor the effects of antidepressants (ADs) both in the brains of healthy volunteers and MDD patients. Although with some discrepancies due to the differences in study designs and patient samples, imaging findings have shown that ADs, particularly those having effects on the serotonergic system, modulate the volumes, functions and biochemistry of brain structures, i.e. dorsolateral prefrontal cortex, anterior cingulate and amygdala, which have been demonstrated abnormal in MDD by earlier imaging studies. This paper reviews imaging studies conducted in MDD patients and healthy controls treated with different ADs.

Selective serotonin reuptake inhibitors (SSRIs) for autism spectrum disorders (ASD)

BACKGROUND

Autism spectrum disorders (ASD) are characterised by abnormalities in social interaction and communication skills, as well as stereotypic behaviours and restricted activities and interests. Selective serotonin reuptake inhibitors (SSRIs) are prescribed for the treatment of co-morbidity associated with ASD such as depression, anxiety and obsessive-compulsive behaviours.

OBJECTIVES

To determine if treatment with an SSRI: 1. improves the core features of autism (social interaction, communication and behavioural problems); 2. improves other non-core aspects of behaviour or function such as self-injurious behaviour; 3. improves the quality of life of children and their carers; 4. has short and long term effects on outcome; 5. causes harms.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 4), MEDLINE ( December 2009), EMBASE (December 2009), CINAHL (December 2009), PsycINFO (December 2009) and ERIC (December 2009), without language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any dose of oral SSRI compared with placebo, in participants with autism spectrum disorders. Trials must have included at least one standardised outcome measure.

DATA COLLECTION AND ANALYSIS

Two authors independently selected and appraised studies for inclusion and risk of bias. All data were continuous. Meta-analysis, where possible, used a random-effects model.

MAIN RESULTS

Seven RCTs with a total of 271 participants were included. Four SSRIs were evaluated: fluoxetine (two studies), fluvoxamine (two studies), fenfluramine (two studies) and citalopram (one study). Five studies included only children and two studies included only adults. Varying inclusion criteria were used with regard to diagnostic criteria and intelligence of participants. Seventeen different outcome measures were reported. Although more than one study reported data for Clinical Global Impression (CGI) and obsessive-compulsive behaviour (OCB), different tool types or components of these outcomes were used in each study. As such, data were unsuitable for meta-analysis. One large, high quality study in children showed no evidence of positive effect of citalopram. Two small studies in adults showed positive outcomes for CGI and OCB; one study showed improvements in aggression and another in anxiety.

AUTHORS' CONCLUSIONS

There is no evidence of effect of SSRIs in children and emerging evidence of harm. There is limited evidence of the effectiveness of SSRIs in adults from small studies in which risk of bias is unclear.

fMRI tracks reductions in repetitive behaviors in autism: two case studies

Autism is characterized by abnormal prefrontal brain activation during cognitive control, a potential biomarker of repetitive behaviors. In this proof-of-principle study, functional magnetic resonance imaging (fMRI) was used to examine brain activity during an oddball task in two high-functioning males with autism before and after 12 weeks of treatment with citalopram, a selective serotonin reuptake inhibitor. One participant showed marked reductions in repetitive behaviors whereas the other showed mild worsening. Brain activation in relevant prefrontal regions increased in only the participant whose repetitive behavior symptoms improved. These findings suggest that fMRI may elucidate potential mechanisms of action of targeted autism interventions.

A pharmacogenetic study of escitalopram in autism spectrum disorders

OBJECTIVE

To determine the effect of serotonin transporter polymorphism promoter region (5-HTTPLR) genotypic variation (low, intermediate, and high expression groups) on response to escitalopram treatment of children and adolescents with autism spectrum disorders (ASDs).

METHOD

The study used a forced titration, open label design, with genotype blind until study completion. Participants were children and adolescents aged 4-17 years of age with a confirmed ASD (autistic disorder, Asperger's disorder, or pervasive developmental disorder, not otherwise specified).

RESULTS

There was an interaction between genotype group and time on the Aberrant Behavior Checklist (ABC) Irritability Subscale (primary outcome variable) (linear maximum marginal likelihood estimation=-4.84, Z=-2.89, SE=1.67, P=0.004). Examination of baseline to last visit revealed that a genotype grouping based on a previous study of platelet 5-HT uptake revealed less response in the genotype group that had S/S genotype for 5-HTTLPR and did not have a diplotype in intron 1 previously shown to be associated with increased platelet 5-HT uptake.

CONCLUSION

This genotype-blind, prospective pharmacogenetic study found the group of subjects with associated with the lowest platelet 5-HT uptake from previous study had the smallest reduction in ABC-Irritability scores after open label treatment with escitalopram. Replication is necessary to confirm these findings.

Laboratory induced aggression: a positron emission tomography study of aggressive individuals with borderline personality disorder

BACKGROUND

Borderline personality disorder (BPD) is often associated with symptoms of impulsive aggression, which poses a threat to patients themselves and to others. Preclinical studies show that orbital frontal cortex (OFC) plays a role in regulating impulsive aggression. Prior work has found OFC dysfunction in BPD.

METHODS

We employed a task to provoke aggressive behavior, the Point Subtraction Aggression Paradigm (PSAP), which has never previously been used during functional brain imaging. Thirty-eight BPD patients with intermittent explosive disorder (BPD-IED) and 36 age-matched healthy control subjects (HCs) received (18)fluoro-deoxyglucose positron emission tomography ((18)FDG-PET) on two occasions with a provocation and nonprovocation version of the PSAP. Mean relative glucose metabolism was measured throughout the cortex, and difference scores (provoked - nonprovoked) were calculated. A whole brain exploratory analysis for the double difference of BPD-IED - HC for provoked - nonprovoked was also conducted.

RESULTS

BPD-IED patients were significantly more aggressive than HCs on the PSAP. BPD-IED patients also increased relative glucose metabolic rate (rGMR) in OFC and amygdala when provoked, while HCs decreased rGMR in these areas. However, HCs increased rGMR in anterior, medial, and dorsolateral prefrontal regions during provocation more than BPD-IED patients.

CONCLUSIONS

Patients responded aggressively and showed heightened rGMR in emotional brain areas, including amygdala and OFC, in response to provocation but not in more dorsal brain regions associated with cognitive control of aggression. In contrast, HCs increased rGMR in dorsal regions of PFC during aggression provocation, brain regions involved in top-down cognitive control of aggression, and, more broadly, of emotion.

Neurological considerations: autism and Parkinson's disease

Within the spectrum of disorders that manifest obsessive-compulsive (OC) features lies a sub-cluster of neurological conditions. Autism and Parkinson's disease (PD) are examples of two such neurological disorders that seem quite dissimilar on the surface. Yet, both conditions can include repetitive behaviors of a compulsive-impulsive nature. Furthermore, while autism and PD differ in other associated symptom domains that shape the course of each disorder, both disorders share some phenomenology in the core domain of repetitive behaviors and involve basal ganglia and frontal lobe dysfunction, similar to OC disorder (OCD). Accordingly, examination of the similarities and differences between autism and PD may provide insight into the pathophysiology and treatment of OC spectrum disorders. The current review focuses on the phenomenology, comorbidity, course of illness, family history, brain circuitry, and treatment of autism and PD, as they relate to OCD and OC spectrum disturbances.

Retrial of selective serotonin reuptake inhibitors in children with pervasive developmental disorders: a retrospective chart review

BACKGROUND

Youths with pervasive developmental disorders (PDDs) often have symptoms that fail to respond to selective serotonin reuptake inhibitor (SSRI) treatment. These children may be given a subsequent trial of another SSRI. This study reports on the outcome of PDD youths who received a second SSRI trial after an initial treatment failure.

METHODS

Clinic charts were reviewed for 22 outpatient youths with a DSM-IV diagnosis of a PDD who were treated with an SSRI after an initial failure with a previous SSRI. Response for the second SSRI trial was determined using the Clinical Global Impressions-Improvement Scale (CGI-I). Treatment indications, symptom severity, demographic data, and side effects were recorded.

RESULTS

For the second SSRI trial, 31.8% of the subjects were rated as much improved on the CGI-I scale and determined to be responders, with 68.2% of the subjects demonstrating activation side effects. 90% of subjects demonstrated activation side effects when data from both SSRI trials were combined. There were no statistically significant associations between outcome of the second SSRI trial and clinical/demographic variables.

CONCLUSIONS

A second trial of an SSRI after an initial SSRI treatment failure was often unsuccessful in children and adolescents with PDDs. Activation side effects were common. Because alternative treatments in this population are limited, a second trial of an SSRI may still be considered. The study was limited by its retrospective design and by its small sample size.

Psychopharmacologic interventions for repetitive behaviors in autism spectrum disorders

This article provides an overview of psychopharmacological treatments for repetitive behaviors in autism spectrum disorders (ASDs) in the context of current conceptualizations of this understudied core symptom domain. The available literature on the widely used selective serotonin reuptake inhibitors (SSRIs), including fluvoxamine, fluoxetine, citalopram, escitalopram, and sertraline, are reviewed. In addition to SSRIs, research on effects of other pharmacologic interventions such as divalproex sodium, risperidone, and the neuropeptide oxytocin are presented. To date, data are mixed for interventions commonly prescribed in clinical practice and suggest several areas of investigation in advancing research on the medication management of repetitive behaviors.

The neurobiology of autism

Improving clinical tests are allowing us to more precisely classify autism spectrum disorders and diagnose them at earlier ages. This raises the possibility of earlier and potentially more effective therapeutic interventions. To fully capitalize on this opportunity, however, will require better understanding of the neurobiological changes underlying this devastating group of developmental disorders. It is becoming clear that the normal trajectory of neurodevelopment is altered in autism, with aberrations in brain growth, neuronal patterning and cortical connectivity. Changes to the structure and function of synapses and dendrites have also been strongly implicated in the pathology of autism by morphological, genetic and animal modeling studies. Finally, environmental factors are likely to interact with the underlying genetic profile, and foster the clinical heterogeneity seen in autism spectrum disorders. In this review we attempt to link the molecular pathways altered in autism to the neurodevelopmental and clinical changes that characterize the disease. We focus on signaling molecules such as neurotrophin, Reelin, PTEN and hepatocyte growth factor, neurotransmitters such as serotonin and glutamate, and synaptic proteins such as neurexin, SHANK and neuroligin. We also discuss evidence implicating oxidative stress, neuroglial activation and neuroimmunity in autism.

Management of children with autism spectrum disorders

Pediatricians have an important role not only in early recognition and evaluation of autism spectrum disorders but also in chronic management of these disorders. The primary goals of treatment are to maximize the child's ultimate functional independence and quality of life by minimizing the core autism spectrum disorder features, facilitating development and learning, promoting socialization, reducing maladaptive behaviors, and educating and supporting families. To assist pediatricians in educating families and guiding them toward empirically supported interventions for their children, this report reviews the educational strategies and associated therapies that are the primary treatments for children with autism spectrum disorders. Optimization of health care is likely to have a positive effect on habilitative progress, functional outcome, and quality of life; therefore, important issues, such as management of associated medical problems, pharmacologic and nonpharmacologic intervention for challenging behaviors or coexisting mental health conditions, and use of complementary and alternative medical treatments, are also addressed.

The status of pharmacotherapy for autism spectrum disorders

The use of pharmacologic agents as a component of treatment for children and adults with autism spectrum disorders is common and a substantial body of literature describing controlled and open-label clinical trials now exists to guide clinical practice. Empiric evidence of efficacy of risperidone, methylphenidate and some selective serotonin re-uptake inhibitors for maladaptive behaviors commonly associated with autism spectrum disorders has increased substantially in recent years. Preliminary controlled trials of valproate, atomoxetine, alpha-2 adrenergic agonists and olanzapine are promising. In addition to traditional psychotropic medications, investigators have examined the potential role of a variety of agents with glutamatergic or cholinergic mechanisms, and the results warrant further investigation. Although psychotropic medications are effective in treating some important associated behaviors, evidence of significant impact on the core features of autism spectrum disorders is very limited.

FDG-PET in never-previously medicated psychotic adolescents treated with olanzapine or haloperidol

We acquired Positron emission tomography with 18-F-deoxyglucose (FDG-PET) and anatomical MRI in 30 never-previously medicated psychotic adolescents (ages 13-20). (FDG-PET) was obtained at baseline and after 8-9 weeks of a randomized double-blind trial of either olanzapine or haloperidol. Neuropsychological tests of executive function were also obtained. Patients carried out the serial verbal learning task, a modification of the California Verbal Learning Test, during the uptake of the FDG. PET scans were coregistered with spoiled gradient MRI (TR=24, TE=5, flip angle 40 degrees, slice thickness 1.2 mm, field of view 230 mm) for accurate anatomical identification of regions of interest traced on the MRI. Twenty-two of the thirty patients completed the second PET and clinical evaluation. Individuals treated with olanzapine increased relative metabolic rates in the frontal lobe more than the occipital lobe while patients treated with haloperidol failed to increase frontal metabolic rates and did not show an anteroposterior gradient in medication response. Haloperidol increased striatal metabolic rate more than olanzapine. Both drugs increased thalamic metabolic rates and this increase was significantly larger in younger (age 13-15) than older (16-21) patients.

Amygdala-prefrontal disconnection in borderline personality disorder

Abnormal fronto-amygdala circuitry has been implicated in impulsive aggression, a core symptom of borderline personality disorder (BPD). We examined relative glucose metabolic rate (rGMR) at rest and after m-CPP (meta-chloropiperazine) with (18)fluorodeoxyglucose (FDG) with positron emission tomography (PET) in 26 impulsive aggressive (IED)-BPD patients and 24 controls. Brain edges/amygdala were visually traced on MRI scans co-registered to PET scans; rGMR was obtained for ventral and dorsal regions of the amygdala and Brodmann areas within the prefrontal cortex (PFC). Correlation coefficients were calculated between rGMR for dorsal/ventral amygdala regions and PFC. Additionally, amygdala volumes and rGMR were examined in BPD and controls. Correlations PFC/amygdala Placebo: Controls showed significant positive correlations between right orbitofrontal (OFC) and ventral, but not dorsal, amygdala. Patients showed only weak correlations between amygdala and the anterior PFC, with no distinction between dorsal and ventral amygdala. Correlations PFC/amygdala: m-CPP response: Controls showed positive correlations between OFC and amygdala regions, whereas patients showed positive correlations between dorsolateral PFC and amygdala. Group differences between interregional correlational matrices were highly significant. Amygdala volume/metabolism: No group differences were found for amygdala volume, or metabolism in the placebo condition or in response to meta-chloropiperazine (m-CPP). We demonstrated a tight coupling of metabolic activity between right OFC and ventral amygdala in healthy subjects with dorsoventral differences in amygdala circuitry, not present in IED-BPD. We demonstrated no significant differences in amygdala volumes or metabolism between BPD patients and controls.

Response monitoring, the error-related negativity, and differences in social behavior in autism

Children with autism not only display social impairments but also significant individual differences in social development. Understanding the source of these differences, as well as the nature of social impairments, is important for improved diagnosis and treatments for these children. Current theory and research suggests that individual differences in response monitoring, a specific function of the anterior cingulate cortex (ACC), may contribute to social-emotional and social-cognitive impairments and individual differences in autism. To examine this hypothesis, we used a modified flanker task to assess an ERP index of response monitoring, the error-related negativity (ERN), in a sample of higher function children with autism (HFA) and an IQ-matched control sample. The results revealed a significant Diagnostic group by Verbal IQ interaction on ERN amplitude indicating that the most verbally capable HFA children displayed significantly larger ERN amplitudes than did the control children. Within the HFA sample, greater ERN amplitude was also related to parent reports of fewer symptoms of social interaction impairments, fewer internalizing problems, but more externalizing problems, although these associations were reduced to nonsignificance when medication status was controlled. The latter results complement previous observations from imaging studies of a significant association between ACC activity and social symptoms and impairments in autism. The implications of these results for future research on brain-behavior relations, as well as treatment related research with children with autism are discussed.

Treatment outcome and outcome associations in children with pervasive developmental disorders treated with selective serotonin reuptake inhibitors: a chart review

PURPOSE

The aim of this study was to determine the outcome and predictors of outcome with selective serotonin reuptake inhibitors (SSRIs) in outpatient children and adolescents with pervasive developmental disorders (PDDs).

METHOD

Clinic charts were reviewed for 89 outpatient youths with a Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) diagnosis of a PDD who were treated with SSRIs. Response was determined using the Clinical Global Impressions (CGI) scale. Side-effect and demographic data, including family history, were recorded.

RESULTS

Forty-four point nine percent (44.9%) were determined to be much improved and considered responders. Fifty-four percent (54%) of the subjects demonstrated activation side effects. In 35.4% of these subjects, the activation side effects led to drug discontinuation. Pearson chi-squared and regression analysis demonstrated an association between SSRI response and a family history of PDD. There were no significant associations between clinical variables and activation side effects.

CONCLUSIONS

SSRI treatment led to modest response rate in this group of youths with PDDs. Activation side effects were frequent, often leading to treatment dropouts. Potential outcome associations include a family history of PDDs.