Autism genome-wide copy number variation reveals ubiquitin and neuronal genes.

Autism spectrum disorders (ASDs) are childhood neurodevelopmental disorders with complex genetic origins. Previous studies focusing on candidate genes or genomic regions have identified several copy number variations (CNVs) that are associated with an increased risk of ASDs. Here we present the results from a whole-genome CNV study on a cohort of 859 ASD cases and 1,409 healthy children of European ancestry who were genotyped with approximately 550,000 single nucleotide polymorphism markers, in an attempt to comprehensively identify CNVs conferring susceptibility to ASDs. Positive findings were evaluated in an independent cohort of 1,336 ASD cases and 1,110 controls of European ancestry. Besides previously reported ASD candidate genes, such as NRXN1 (ref. 10) and CNTN4 (refs 11, 12), several new susceptibility genes encoding neuronal cell-adhesion molecules, including NLGN1 and ASTN2, were enriched with CNVs in ASD cases compared to controls (P = 9.5 x 10(-3)). Furthermore, CNVs within or surrounding genes involved in the ubiquitin pathways, including UBE3A, PARK2, RFWD2 and FBXO40, were affected by CNVs not observed in controls (P = 3.3 x 10(-3)). We also identified duplications 55 kilobases upstream of complementary DNA AK123120 (P = 3.6 x 10(-6)). Although these variants may be individually rare, they target genes involved in neuronal cell-adhesion or ubiquitin degradation, indicating that these two important gene networks expressed within the central nervous system may contribute to the genetic susceptibility of ASD.

A randomized double-blind, placebo-controlled pilot trial of mirtazapine for anxiety in children and adolescents with autism spectrum disorder.

This study was a 10-week double-blind, placebo-controlled pilot trial of mirtazapine for anxiety in youth with autism spectrum disorder (ASD). Participants were ages 5 to 17 years with ASD and clinically significant anxiety (Pediatric Anxiety Rating Scale [PARS] score ≥10). Thirty participants were randomized to mirtazapine (7.5-45 mg/day) or placebo in a 2:1 ratio. The co-primary outcome measures were the PARS and the Clinical Global Impressions-Improvement subscale (CGI-I). Mirtazapine resulted in a statistically significant within group decrease in anxiety on the PARS (ES 1.76, p < 0.001). The improvement in PARS score for mirtazapine versus placebo was clinically meaningful but not statistically significant (ES = 0.63, p = 0.64). Forty-seven percent of participants assigned to mirtazapine (95% CI 22%: 74%) and 20% assigned to placebo (95% CI 2%: 60%) were rated "much improved" (CGI-I = 2) or "very much improved" (CGI-I = 1) for anxiety, p = 0.46. No statistically significant differences in mean 10-week changes between mirtazapine and placebo occurred on any outcome measure. There were no statistically significant differences in adverse effect frequency between mirtazapine and placebo. The results are consistent with mirtazapine's safety and tolerability and meet three of four pre-specified indicators of efficacy (statistically significant change in total PARS score for mirtazapine, numerically greater reduction in total PARS score for mirtazapine than placebo, numerically higher number of responders to mirtazapine than placebo, but not greater than 50% of participants receiving mirtazapine rated as responders). Implementation of a larger randomized controlled trial of mirtazapine for the treatment of anxiety in this population is supported.Clinical trial registration information: Mirtazapine Treatment of Anxiety in Children and Adolescents with Pervasive Developmental Disorders; https://clinicaltrials.gov ; NCT01302964.

Antipsychotics in the treatment of autism.

Atypical antipsychotics have become indispensable in the treatment of a variety of symptoms in autism. They are frequently used to treat irritability and associated behaviors including aggression and self injury. They may also be efficacious for hyperactivity and stereotyped behavior. This review presents the rationale for the use of this drug class in autism and reviews the most important studies published on this topic to date. Significant adverse effects, including weight gain and the possibility of tardive dyskinesia, are reviewed. Future research directions are discussed.

Developing drugs for core social and communication impairment in autism.

There are many challenges to studying drug effects on core social and language impairment in autism. Drugs such as fenfluramine, naltrexone, and secretin do not appear to be efficacious for these core symptoms. Risperidone has led to improvement in some aspects of social relatedness when used to treat irritability in autism. More research is needed on the utility of selective serotonin reuptake inhibitors, cholinergic drugs, glutamatergic drugs, and oxytocin for core autistic symptoms.

Effects of short- and long-term risperidone treatment on prolactin levels in children with autism.

BACKGROUND: The effects of short- and long-term risperidone treatment on serum prolactin were assessed in children and adolescents with autism. METHODS: Patients with autism (N = 101, 5-17 years of age) were randomized to an 8-week trial of risperidone or placebo and 63 then took part in a 4-month open-label follow-up phase. Serum samples were obtained at Baseline and Week-8 (N = 78), and at 6-month (N = 43) and 22-month (N = 30) follow-up. Serum prolactin was determined by immunoradiometric assay; dopamine type-2 receptor (DRD2) polymorphisms were genotyped. RESULTS: Baseline prolactin levels were similar in the risperidone (N = 42) and placebo (N = 36) groups (9.3 +/- 7.5 and 9.3 +/- 7.6 ng/ml, respectively). After 8 weeks of risperidone, prolactin increased to 39.0 +/- 19.2 ng/ml, compared with 10.1 +/- 8.8 ng/ml for placebo (p < .0001). Prolactin levels were also significantly increased at 6 months (32.4 +/- 17.8 ng/ml; N = 43, p < .0001) and at 22 months (N = 30, 25.3 +/- 15.6 ng/ml, p < .0001). Prolactin levels were not associated with adverse effects and DRD2 alleles (Taq1A, -141C Ins/Del, C957T) did not significantly influence baseline levels or risperidone-induced increases in prolactin. CONCLUSIONS: Risperidone treatment was associated with two- to four-fold mean increases in serum prolactin in children with autism. Although risperidone-induced increases tended to diminish with time, further research on the consequences of long-term prolactin elevations in children and adolescents is needed.

Positive effects of methylphenidate on inattention and hyperactivity in pervasive developmental disorders: an analysis of secondary measures.

BACKGROUND: Methylphenidate has been shown elsewhere to improve hyperactivity in about half of treated children who have pervasive developmental disorders (PDD) and significant hyperactive-inattentive symptoms. We present secondary analyses to better define the scope of effects of methylphenidate on symptoms that define attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD), as well as the core autistic symptom domain of repetitive behavior. METHODS: Sixty-six children (mean age 7.5 y) with autistic disorder, Asperger's disorder, and PDD not otherwise specified, were randomized to varying sequences of placebo and three different doses of methylphenidate during a 4-week blinded, crossover study. Methylphenidate doses used approximated .125, .25, and .5 mg/kg per dose, twice daily, with an additional half-dose in the late afternoon. Outcome measures included the Swanson, Nolan, and Pelham Questionnaire revised for DSM-IV (ADHD and ODD scales) and the Children's Yale-Brown Obsessive Compulsive Scales for PDD. RESULTS: Methylphenidate was associated with significant improvement that was most evident at the .25- and .5-mg/kg doses. Hyperactivity and impulsivity improved more than inattention. There were not significant effects on ODD or stereotyped and repetitive behavior. CONCLUSIONS: Convergent evidence from different assessments and raters confirms methylphenidate's efficacy in relieving ADHD symptoms in some children with PDD. Optimal dose analyses suggested significant interindividual variability in dose response.

A retrospective study of memantine in children and adolescents with pervasive developmental disorders.

RATIONALE: There are no drugs that have been shown to effectively treat the core social impairment of autism. OBJECTIVES: The purpose of this study was to examine the effectiveness and tolerability of memantine for social impairment in children and adolescents with pervasive developmental disorders (PDDs). MATERIALS AND METHODS: Medical records of 18 patients with PDDs consecutively treated with open-label memantine were retrospectively reviewed. The data reviewed included prospectively obtained assessments of severity (S) and improvement (I) using the Clinical Global Impressions Scale (CGI). Pretrial and follow-up parent ratings were also available on six patients using the Aberrant Behavior Checklist (ABC). RESULTS: Eighteen patients (15 male, 3 female; mean age=11.4 years, range 6-19 years) received memantine (mean dosage=10.1 mg/day, range 2.5-20 mg/day) over a mean duration of 19.3 weeks (range 1.5-56 weeks). Eleven of 18 (61%) patients were judged responders to memantine based on a rating of "much improved" or "very much improved" on the CGI-I. Significant improvement was also seen on the CGI-S. Improvement was primarily seen clinically in social withdrawal and inattention. Adverse effects occurred in 7 of 18 (39%) patients and led to drug discontinuation in 4 of 18 (22%) patients. Thirteen of 18 (72%) patients received stable doses of concomitant medications during the memantine trial. CONCLUSIONS: In this open-label retrospective study, memantine was effective in a number of patients with PDDs. Controlled studies are warranted to further assess the efficacy and safety of memantine in PDDs.

d-Cycloserine enhances durability of social skills training in autism spectrum disorder.

BACKGROUND: d-Cycloserine (DCS) enhances extinction learning across species, but it has proven challenging to identify consistent benefit of DCS when added to therapeutic interventions. We conducted a placebo-controlled trial of DCS to potentiate social skills training in autism spectrum disorder (ASD) but found substantial improvement in both the DCS and placebo groups at the conclusion of active treatment. Here, we assess the impact of DCS 11 weeks following active treatment to evaluate the impact of DCS on treatment response durability. METHODS: Study participants included 60 outpatient youth with ASD, ages 5-11 years, all with IQ above 70, and significantly impaired social functioning who completed a 10-week active treatment phase during which they received weekly single doses of 50 mg of DCS or placebo administered 30 min prior to group social skills training. Following the 10-week active treatment phase, blinded follow-up assessments occurred at week 11 and week 22. The primary outcome measure for our durability of treatment evaluation was the parent-rated social responsiveness scale (SRS) total raw score at week 22. RESULTS: Analysis of the SRS total raw score demonstrated significant decrease for the DCS group compared to the placebo group (p = 0.042) indicating greater maintenance of treatment effect in the DCS group. DCS was well tolerated, with irritability being the most frequently reported adverse effect in both groups. CONCLUSIONS: The findings of this study suggest that DCS may help youth with ASD to maintain skills gained during sort-term social skills training. Larger-scale studies with longer follow-up will be necessary to further understand the long-term impact of DCS paired with structured social skills training. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01086475.

Children's Yale-Brown Obsessive Compulsive Scale modified for pervasive developmental disorders.

OBJECTIVE: To examine the psychometric properties of the Children's Yale-Brown Obsessive Compulsive Scales (CYBOCS) modified for pervasive developmental disorders (PDDs). METHOD: Raters from five Research Units on Pediatric Psychopharmacology (RUPP) Autism Network were trained to reliability. The modified scale (CYBOCS-PDD), which contains only the five Compulsion severity items (range 0-20), was administered to 172 medication-free children (mean 8.2 +/- 2.6 years) with PDD (autistic disorder, n = 152; Asperger's disorder, n = 6; PDD not otherwise specified, n = 14) participating in RUPP clinical trials. Reliability was assessed by intraclass correlation coefficient (ICC) and internal consistency by Cronbach's alpha coefficient. Correlations with ratings of repetitive behavior and disruptive behavior were examined for validity. RESULTS: Eleven raters showed excellent reliability (ICC = 0.97). The mean CYBOCS score was 14.4 (+/- 3.86) with excellent internal consistency (alpha = .85). Correlations with other measures of repetitive behavior ranged from r = 0.11 to r = 0.28 and were similar to correlations with measures of irritability (r = 0.24) and hyperactivity (r = 0.25). Children with higher scores on the CYBOCS-PDD had higher levels of maladaptive behaviors and lower adaptive functioning. CONCLUSIONS: The five-item CYBOCS-PDD is reliable, distinct from other measures of repetitive behavior, and sensitive to change.

Risperidone and adaptive behavior in children with autism.

OBJECTIVE: To evaluate the impact of risperidone on adaptive behavior in children with autistic disorder who have serious behavior problems and to examine different methods of scoring the Vineland Adaptive Behavior Scales to measure change. METHOD: Forty-eight children (5 years to 16 years, 5 months) who showed behavioral improvement during acute treatment with risperidone were followed for 6 months and assessed with the Vineland Scales. RESULTS: Raw scores, age-equivalents, and special norm percentile scores all showed significant increases in adaptive behavior in the areas of communication, daily living skills, and socialization (p <.01). During a period of 6 to 8 months, children gained an average of 7.8 age-equivalent months in the area of socialization, a > 6% improvement beyond what would be expected based on baseline growth rates. CONCLUSIONS: Although limited by the absence of a control group, these results suggest that risperidone may improve adaptive skills in children with autistic disorder accompanied by serious behavioral problems. Vineland age-equivalent scores appear to be most useful in assessing change with treatment over time.

Ramelteon for insomnia in two youths with autistic disorder.

OBJECTIVE: The aim of this study was to report preliminary data on the effectiveness and tolerability of ramelteon for the treatment of insomnia in youth with autistic disorder (autism). METHOD: Two youths, ages 7 and 18 years, with autism and significant insomnia characterized by problems with sleep onset and maintenance received an open-label trial of ramelteon (4-8 mg) over a duration of 16-18 weeks. RESULTS: Target symptoms of delayed sleep onset and/or frequent nocturnal awakening improved significantly, as determined by Clinical Global Impressions-Improvement (CGI-I) scale ratings of either "much improved" or "very much improved." Ramelteon was well tolerated. No daytime sedation was reported. CONCLUSIONS: This case report illustrates the potential effectiveness and tolerability of ramelteon for sleep disturbances in 2 patients with autism. Further research is needed to verify its safety, tolerability, and efficacy in children and adolescents with autism.

The use of selective serotonin reuptake inhibitors in autism and related disorders.

This paper reviews the published literature on the use of selective serotonin reuptake inhibitors (SSRIs) for the treatment of symptoms associated with autistic disorder and other pervasive developmental disorders (PDDs) in both children and adults. To date, placebocontrolled studies of SSRIs have involved only fluvoxamine (in children and adults) and fluoxetine (in children). Open-label and retrospective studies of all other SSRIs in PDDs have also been published that suggest effectiveness. Despite these positive reports, there continues to be questions about the tolerability and appropriate dosing of SSRIs in children with PDDs. Because of the limited number of placebo-controlled studies, definitive conclusions about the role SSRIs should play in the clinical treatment of children with PDDs cannot be drawn. Larger, placebo-controlled studies of SSRIs are needed to guide clinical treatment.

Open-label atomoxetine for attention-deficit/ hyperactivity disorder symptoms associated with high-functioning pervasive developmental disorders.

OBJECTIVE: The aim of this study was to conduct an initial evaluation of the efficacy of atomoxetine for attention-deficit/hyperactivity disorder (ADHD) symptoms in children with pervasive developmental disorders (PDDs). METHOD: Children with PDDs and a nonverbal IQ of >or=70 received atomoxetine (target dose 1.2-1.4 mg/kg/day) during the course of an 8-week, open-label, prospective study. Standardized assessments of efficacy and tolerability were collected at regular intervals during the trial. RESULTS: Sixteen children and adolescents (mean age 7.7 +/- 2.2 years, age range 6-14 years) with autistic disorder (n = 7), Asperger's disorder (n = 7), or PDD not otherwise specified (n = 2) received atomoxetine (mean dose 1.2 +/- 0.3 mg/kg/day). Twelve participants (75%) were rated as "much" or "very much improved" on the Clinical Global Impressions-Improvement scale. The most significant improvement was seen in the area of ADHD symptoms as measured by the SNAP-IV and Aberrant Behavior Checklist (effect size = 1.0-1.9). Improvements of lesser magnitude (effect size = 0.4-1.1) were seen in irritability, social withdrawal, stereotypy, and repetitive speech. There were no significant changes on the Conners' Continuous Performance Test. Atomoxetine was well tolerated with the exception of 2 participants (13 %) who stopped medication due to irritability. Weight decreased by a mean of 0.8 kg during the 8-week trial. CONCLUSIONS: Placebo-controlled studies are indicated to determine atomoxetine's efficacy for ADHD symptoms in PDDs.

Validity of the autism diagnostic interview-revised.

The factor structure, internal consistency, and convergent validity of the Autism Diagnostic Interview-Revised (ADI-R) algorithm items were examined in a sample of 226 youngsters with pervasive developmental disabilities. Exploratory factor analyses indicated a three-factor solution closely resembling the original algorithm and explaining 38% of the variance, with one significant discrepancy: Unlike the algorithm, all nonverbal communication items were associated with the Social factor. Internal consistencies of domain scores ranged from .54 to .84. Correlations between ADI-R domain and total scores and instruments assessing adaptive behavior, psychopathology, and autism were examined. They indicated some similarities between constructs, but also that the ADI-R measures autism in a unique fashion.

A randomized placebo-controlled pilot study of N-acetylcysteine in youth with autism spectrum disorder.

BACKGROUND: Social impairment is a defining feature of autism spectrum disorder (ASD) with no demonstrated effective pharmacologic treatments. The goal of this study was to evaluate efficacy, safety, and tolerability of oral N-acetylcysteine (NAC), an antioxidant whose function overlaps with proposed mechanisms of ASD pathophysiology, targeting core social impairment in youth with ASD. METHODS: This study was a 12-week randomized, double-blind, placebo-controlled trial of oral NAC in youth with ASD. Study participants were medically healthy youth age 4 to 12 years with ASD, weighing ≥15 kg, and judged to be moderately ill based on the Clinical Global Impressions Severity scale. The participants were randomized via computer to active drug or placebo in a 1:1 ratio, with the target dose of NAC being 60 mg/kg/day in three divided doses. The primary outcome measure of efficacy was the Clinical Global Impressions Improvement (CGI-I) scale anchored to core social impairment. To investigate the impact of NAC on oxidative stress markers in peripheral blood, venous blood samples were collected at screen and week 12. RESULTS: Thirty-one patients were enrolled (NAC = 16, placebo = 15). Three participants were lost to follow-up, and three left the trial due to adverse effects. The average daily dose of NAC at week 12 was 56.2 mg/kg (SD = 9.7) with dose ranging from 33.6 to 64.3 mg/kg. The frequency of adverse events was so low that comparisons between groups could not be conducted. At week 12, there was no statistically significant difference between the NAC and placebo groups on the CGI-I (p > 0.69) but the glutathione (GSH) level in blood was significantly higher in the NAC group (p < 0.05). The oxidative glutathione disulfide (GSSG) level increased in the NAC group, however only at a trend level of significance (p = 0.09). There was no significant difference between the NAC and placebo groups in the GSH/GSSG ratio, DNA strand break and oxidative damage, and blood homocysteine levels at week 12 (ps > 0.16). CONCLUSIONS: The results of this trial indicate that NAC treatment was well tolerated, had the expected effect of boosting GSH production, but had no significant impact on social impairment in youth with ASD. TRIAL REGISTRATION: Clinicaltrials.gov NCT00453180.

A randomized, placebo-controlled trial of D-cycloserine for the enhancement of social skills training in autism spectrum disorders.

BACKGROUND: Researchers have demonstrated that d-cycloserine (DCS) can enhance the effects of behavioral interventions in adults with anxiety and enhances prosocial behavior in animal models of autism spectrum disorders (ASD). This study extended upon this background by combining DCS with behavioral social skills therapy in youth with ASD to assess its impact on the core social deficits of ASD. We hypothesized that DCS used in combination with social skills training would enhance the acquisition of social skills in children with ASD. METHODS: A 10-week, double-blind, placebo-controlled trial of DCS (50 mg) given 30 min prior to weekly group social skills training was conducted at two sites. Children with ASD were randomized to receive 10 weeks (10 doses) of DCS or placebo in a 1:1 ratio. RESULTS: No statistically significant difference attributable to drug treatment was observed in the change scores for the primary outcome measure, the Social Responsiveness Scale (SRS), total score (p = 0.45), or on secondary outcome measures. CONCLUSIONS: The results of this trial demonstrated no drug-related short-term improvement on the primary outcome measure, or any of the secondary outcome measures. However, an overall significant improvement in SRS total raw score was observed from baseline to end of treatment for the entire group of children with ASD. This suggests a need to further study the efficacy of the social skills training protocol. Limitations to the current study and areas for future research are discussed. TRIAL REGISTRATION: ClinicalTrials.govNCT01086475.

Risperidone for the core symptom domains of autism: results from the study by the autism network of the research units on pediatric psychopharmacology.

OBJECTIVE: Risperidone has been found efficacious for decreasing severe tantrums, aggression, and self-injurious behavior in children and adolescents with autistic disorder (autism). The authors report on whether risperidone improves the core symptoms of autism, social and communication impairment and repetitive and stereotyped behavior. METHOD: The database from an 8-week double-blind, placebo-controlled trial (N=101) and 16-week open-label continuation study (N=63) of risperidone for children and adolescents with autism was used to test for drug effects on secondary outcome measures: scores on the Ritvo-Freeman Real Life Rating Scale, the Children's Yale-Brown Obsessive Compulsive Scale, and the maladaptive behavior domain of the Vineland Adaptive Behavior Scales. RESULTS: Compared to placebo, risperidone led to a significantly greater reduction in the overall score on the Ritvo-Freeman Real Life Rating Scale, as well as the scores on the subscales for sensory motor behaviors (subscale I), affectual reactions (subscale III), and sensory responses (subscale IV). No statistically significant difference was observed, however, on the subscale for social relatedness (subscale II) or language (subscale V). Risperidone also resulted in significantly greater reductions in scores on the Children's Yale-Brown Obsessive Compulsive Scale and Vineland maladaptive behavior domain. This pattern of treatment response was maintained for 6 months. CONCLUSIONS: Risperidone led to significant improvements in the restricted, repetitive, and stereotyped patterns of behavior, interests, and activities of autistic children but did not significantly change their deficit in social interaction and communication. Further research is necessary to develop effective treatments for the core social and communicative impairments of autism.

Neurochemistry in the pathophysiology of autism.

Significant progress has been made in the search for underlying pathophysiologic mechanisms in autism over the past 50 years. The cause of the disorder, however, remains largely unknown. This article reviews neurochemical contributions to the pathophysiology of autism with a focus on monoamines, glutamate/gamma-aminobutyric acid systems, and neuropeptides. As these efforts move forward, it will be important to begin to integrate genetic studies with those involving neuroimaging and postmortem research in each of these 3 areas, as well as with pharmacologic treatment approaches.

Gastrointestinal factors in autistic disorder: a critical review.

Interest in the gastrointestinal (GI) factors of autistic disorder (autism) has developed from descriptions of symptoms such as constipation and diarrhea in autistic children and advanced towards more detailed studies of GI histopathology and treatment modalities. This review attempts to critically and comprehensively analyze the literature as it applies to all aspects of GI factors in autism, including discussion of symptoms, pathology, nutrition, and treatment. While much literature is available on this topic, a dearth of rigorous study was found to validate GI factors specific to children with autism.