An exploration of concomitant psychiatric disorders in children with autism spectrum disorder.

OBJECTIVE: We explored patterns of concomitant psychiatric disorders in a large sample of treatment-seeking children and adolescents with autism spectrum disorder (ASD). METHODS: Participants were 658 children with ASD (age 3-17 years; mean = 7.2 years) in one of six federally-funded multisite randomized clinical trials (RCT) between 1999 and 2014. All children were referred for hyperactivity or irritability. Study designs varied, but all used the Child and Adolescent Symptom Inventory or Early Childhood Inventory to assess Attention Deficit Hyperactivity Disorder (ADHD), Oppositional-Defiant Disorder (ODD), Conduct Disorder (CD), Anxiety Disorders, and Mood Disorders. In addition, several measures in common were used to assess demographic and clinical characteristics. RESULTS: Of the 658 children, 73% were Caucasian and 59% had an IQ >70. The rates of concomitant disorders across studies were: ADHD 81%, ODD 46%, CD 12%, any anxiety disorder 42%, and any mood disorder 8%. Two or more psychiatric disorders were identified in 66% of the sample. Of those who met criteria for ADHD, 50% also met criteria for ODD and 46% for any anxiety disorder. Associations between types of concomitant disorders and a number of demographic and clinical characteristics are presented. CONCLUSION: In this well-characterized sample of treatment-seeking children with ASD, rates of concomitant psychiatric disorders were high and the presence of two or more co-occurring disorders was common. Findings highlight the importance of improving diagnostic practice in ASD and understanding possible mechanisms of comorbidity.

Applicability and Psychometric Properties of General Mental Health Assessment Tools in Autistic People: A Systematic Review.

In recent years, there has been a proliferation of instruments for assessing mental health (MH) among autistic people. This study aimed to review the psychometric properties of broadband instruments used to assess MH problems among autistic people. In accordance with the PRISMA guidelines (PROSPERO: CRD42022316571) we searched the APA PsycINFO via Ovid, Ovid MEDLINE, Ovid Embase and the Web of Science via Clarivate databases from 1980 to March 2022, with an updated search in January 2024, to identify very recent empirical studies. Independent reviewers evaluated the titles and abstracts of the retrieved records (n = 11,577) and full-text articles (n = 1000). Data were extracted from eligible studies, and the quality of the included papers was appraised. In all, 164empirical articles reporting on 35 instruments were included. The review showed variable evidence of reliability and validity of the various instruments. Among the instruments reported in more than one study, the Aberrant Behavior Checklist had consistently good or excellent psychometric evidence. The reliability and validity of other instruments, including: the Developmental Behavior Checklist, Emotion Dysregulation Inventory, Eyberg Child Behavior Inventory, Autism Spectrum Disorder-Comorbid for Children Scale, and Psychopathology in Autism Checklist, were less documented. There is a need for a greater evidence-base for MH assessment tools for autistic people.

Executive Function in Autism: Association with ADHD and ASD Symptoms.

There is substantial comorbidity between autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD), and there are well-documented executive functioning (EF) deficits in both populations. An important question concerns whether EF deficits in children with ASD are related to severity of ASD, ADHD, or both. We examined ADHD and ASD symptoms in relation to ratings of EF in the home and classroom. The sample comprised 64 children (55 males) diagnosed with ASD (mean age = 9.26 years; mean FSIQ = 92). Analyses indicated that parent and teacher ratings of EF (except Shift and Emotional Control) were consistently related to ADHD symptom severity, but not to ASD severity. Thus, functioning in the domains of Shift and Emotional control appear relatively spared, whereas performance in all other EF was impaired in relation to ADHD symptoms.

Population pharmacokinetic modeling of risperidone and 9-hydroxyrisperidone to estimate CYP2D6 subpopulations in children and adolescents.

AIM: The study aims were to characterize risperidone and (±)-9-hydroxyrisperidone pharmacokinetic (PK) variability in children and adolescents and to evaluate covariate effects on PK parameters. METHODS: Steady-state samples were drawn at predose, 1, 2, 4, and 7 hours postdose; cytochrome P450 2D6 (CYP2D6) genotypes were available for 28 subjects. A nonlinear mixed-effects model (NONMEM) modeled the PKs of risperidone and (±)-9-hydroxyrisperidone; covariates included age, weight, sex, and CYP2D6 phenotype. The model included 497 observations [risperidone (n = 163), (+) and (-)-9-hydroxyrisperidone (n = 334)] from 45 subjects aged 3-18.3 (mean 9.6 ± 3.7) years, weighing 16.8-110 (43 ± 20.2) kg. RESULTS: A 1-compartment mixture model described risperidone and (±)-9-hydroxyrisperidone clearances for 3 CYP2D6 metabolizer subpopulations: extensive, intermediate, and poor. Weight significantly affected (±)-9-hydroxyrisperidone clearance. Clearance estimates in the mixture model were poor metabolizer 9.38 L/h, intermediate metabolizer 29.2 L/h, and extensive metabolizer 37.4 L/h. CONCLUSION: Active moiety [risperidone plus (±)-9-hydroxyrisperidone] PK variability and the covariate effects were better explained with the addition of metabolite PK parameters. This model may aid the development of individualized risperidone dosing regimens in children and adolescents.

ADHD severity as a predictor of cognitive task performance in children with Autism Spectrum Disorder (ASD).

BACKGROUND: In recent years, a number of studies have begun to explore the nature of Attention-Deficit/Hyperactivity Disorder (ADHD) in children with Autism Spectrum Disorder (ASD). In this study, we examined the relationship between both symptoms of ADHD and symptoms of ASD on cognitive task performance in a sample of higher-functioning children and adolescents with ASD. Participants completed cognitive tasks tapping aspects of attention, impulsivity/inhibition, and immediate memory. AIMS: We hypothesized that children with ASD who had higher levels of ADHD symptom severity would be at higher risk for poorer sustained attention and selective attention, greater impulsivity/disinhibition, and weaker memory. METHODS AND PROCEDURES: The sample included 92 children (73 males) diagnosed with ASD (Mean Age = 9.41 years; Mean Full Scale IQ = 84.2). OUTCOMES AND RESULTS: Using regression analyses, more severe ADHD symptomatology was found to be significantly related to weaker performance on tasks measuring attention, immediate memory, and response inhibition. In contrast, increasing severity of ASD symptomatology was not associated with higher risk of poorer performance on any of the cognitive tasks assessed. CONCLUSIONS AND IMPLICATIONS: These results suggest that children with ASD who have more severe ADHD symptoms are at higher risk for impairments in tasks assessing attention, immediate memory, and response inhibition-similar to ADHD-related impairments seen in the general pediatric population. As such, clinicians should assess various aspects of cognition in pediatric patients with ASD in order to facilitate optimal interventional and educational planning.

Factor Structure of the Aberrant Behavior Checklist in Individuals with Fragile X Syndrome: Clarifications and Future Guidance.

Objective: The Aberrant Behavior Checklist (ABC) is a standardized rating scale used for assessing problematic behavior of individuals with developmental disabilities. It has five subscales: Irritability, Social Withdrawal, Stereotypic Behavior, Hyperactivity, and Inappropriate Speech. A previous study in individuals with fragile X syndrome (FXS) reported six factors, with the Social Withdrawal factor bifurcating into Socially Unresponsive and Social Avoidance factors, suggesting a different factor structure in people with FXS. Methods: We assessed the ABC's factor structure (with both exploratory and confirmatory analyses) in 797 people with FXS and we compared these findings with exploratory factors derived from an independent sample of 357 individuals with FXS. In an ancillary analysis, we compared the overlap of the traditional ABC's Social Withdrawal scores with the Social Avoidance scores from the FXS-derived newer scale to determine whether overlap between these was very high and essentially redundant. Finally, we computed norms using both the traditional and the FXS-specific algorithms. Results: In confirmatory factor analyses, the FXS-specific algorithm produced the most consistent factor structure for the sample of 797 participants, but model fit was only marginally better than that derived by the original ABC scoring algorithm. Comparisons of factor structures from separate exploratory analyses revealed no consistent advantage of the FXS algorithm over the traditional algorithm. While a Social Avoidance subscale did emerge in some analyses, in other analyses, this was accompanied by loss of coherence on other domains of interest, such as the Socially Unresponsive/Social Withdrawal subscale. Conclusion: We question whether the newer FXS scoring algorithm contributes data that are consistently helpful in evaluating behavior of people with FXS. In general, we recommend continued use of the original ABC algorithm for scoring behavior of clients with FXS. However, we acknowledge that there may be circumscribed times when the new algorithm may be appropriate for scoring, namely when anxiety and/or social avoidance constructs are the central and unequivocal domains of interest.

Clinical Validation of the Autism Behavior Inventory: Caregiver-Rated Assessment of Core and Associated Symptoms of Autism Spectrum Disorder.

There is a need for measures to track symptom change in autism spectrum disorder (ASD). We conducted a validation study on a revised version of the Autism Behavior Inventory (ABI), and a short form (ABI-S). Caregivers of individuals (6-54 years) with confirmed diagnoses of ASD (N = 144) completed the ABI and other rating scales at 4 time points. Scale consistency for each domain, 3-5 day test-retest reliability, and construct validity, determined by comparison to pre-specified scales, were all good. Change in the ABI was congruent with changes in other instruments. Collectively, results suggest incipient suitability of the ABI as a measure of changes in core and associated symptoms of ASD.Trial Registration NCT02299700.

Development of a Composite Primary Outcome Score for Children with Attention-Deficit/Hyperactivity Disorder and Emotional Dysregulation.

Objective: Study goals were to (1) provide a rationale for developing a composite primary outcome score that includes symptom severity for attention-deficit/hyperactivity disorder (ADHD) and emotional dysregulation, plus symptom-induced impairment; (2) demonstrate weighting methods to calculate the composite score using a sample of children diagnosed with ADHD and aggression; and (3) identify the optimal weighting method most sensitive to change, as measured by effect sizes. Methods: We conducted secondary data analyses from the previously conducted Treatment of Severe Childhood Aggression (TOSCA) study. Children aged 6-12 years were recruited through academic medical centers or community referrals. The composite primary outcome comprised the ADHD, oppositional defiant disorder, disruptive mood dysregulation disorder, and peer conflict subscales from the Child and Adolescent Symptom Inventory (CASI), a DSM (Diagnostic and Statistical Manual)-referenced rating scale of symptom severity and symptom-induced impairment. Five weighting methods were tested based on input from senior statisticians. Results: The composite score demonstrated a larger (Cohen's d) effect size than the individual CASI subscales, irrespective of the weighting method (10%-55% larger). Across all weighting methods, effect sizes were similar and substantial: approximately a two-standard deviation symptom reduction (range: -1.97 to -2.04), highest for equal item and equal subscale weighting, was demonstrated, from baseline to week 9, among all TOSCA participants. The composite score showed a medium positive correlation with the Clinical Global Impressions-Severity scores, 0.46-0.47 for all weighting methods. Conclusions: A composite score that included severity and impairment ratings of ADHD and emotional dysregulation demonstrated a more robust pre-post change than individual subscales. This composite may be a more useful indicator of clinically relevant improvement in heterogeneous samples with ADHD than single subscales, avoiding some of the statistical limitations associated with multiple comparisons. Among the five similar weighting methods, the two best appear to be the equal item and equal subscale weighting methods.

Standardized Observation Analogue Procedure in the Treatment of Severe Childhood Aggression Study.

Objective: To explore blinded observational outcomes in the Treatment of Severe Childhood Aggression (TOSCA) study. Methods: During a 9-week acute trial, children with severe physical aggression and attention-deficit/hyperactivity disorder received parent training + titrated psychostimulant for 3 weeks, and those who failed to show an optimal response during Week 4 through Week 6 received in addition either randomly assigned placebo (Basic treatment) or titrated risperidone (Augmented treatment). Child and parent behaviors were videotaped in a Standardized Observation Analogue Procedure (SOAP) designed to elicit problems and strengths in child and parent interactions. SOAPs were collected at baseline and Week 9 and 52 follow-up. Results: During the acute 9-week trial, augmented treatment was associated with better outcomes than basic treatment for 3 of 13 measures: increased Child Compliance (p = 0.004; significant after correction for multiple tests), greater use of positive Parent Reinforcement (p = 0.03), and more Shared Enjoyment (p = 0.04). At follow-up, when medication was no longer by randomized assignment, parents used more Alpha Commands and displayed fewer Parent Negative Behaviors, and the dyads showed more Shared Enjoyment regardless of original randomization. Thus, there were better parent-child interactions with Augmented treatment, and interactions improved overall at follow-up regardless of original treatment assignment. Conclusions: The SOAP demonstrated sensitivity to behavior changes between short-term treatments for a few (but not most) measures. The acute treatment differences for Child Compliance and Child Negative Behavior are generally consistent with the moderate superiority of Augmented over Basic treatment previously reported for the primary study outcome.

Effects of Extended-Release Methylphenidate Treatment on Cognitive Task Performance in Children with Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder.

Objective: To examine the effectiveness of four doses of psychostimulant medication, combining extended-release methylphenidate (ER-MPH) in the morning with immediate-release MPH (IR-MPH) in the afternoon, on cognitive task performance. Method: The sample comprised 24 children (19 boys and 5 girls) who met the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition Text Revision (DSM-IV-TR) criteria for an autism spectrum disorder (ASD) on the Autism Diagnostic Interview-R and the Autism Diagnostic Observation Schedule, and had significant symptoms of attention-deficit/hyperactivity disorder (ADHD). This sample consisted of elementary school-age, community-based children (mean chronological age = 8.8 years, SD = 1.7; mean intelligence quotient = 85; SD = 16.8). Effects of placebo and three dose levels of ER-MPH (containing 0.21, 0.35, and 0.48 mg/kg equivalent of IR-MPH) on cognitive task performance were compared using a within-subject, crossover, placebo-controlled design. Each of the four MPH dosing regimens (placebo, low-dose MPH, medium-dose MPH, and high-dose MPH) was administered for 1 week; the dosing order was counterbalanced across children. Results: MPH treatment was associated with significant performance gains on cognitive tasks tapping sustained attention, selective attention, and impulsivity/inhibition. Dose/response was generally linear in the dose range studied, with no evidence of deterioration in performance at higher MPH doses in the dose range studied. Conclusion: The results of this study suggest that MPH formulations are associated with significant improvements on cognitive task performance in children with ASD and ADHD.

Validity of the aberrant behavior checklist in a clinical sample of toddlers.

We investigated the congruent and criterion validity of the Aberrant Behavior Checklist (ABC) in a clinical sample of toddlers seen over 1 year in Turkey. All consecutive patients (N=93), 14-43 months old (mean, 30.6 mos.), in a child psychiatry outpatient clinic were included. The ABC, Autism Behavior Checklist (AuBC), and Child Behavior Checklist 2/3 (CBCL) were completed by the children's parents. Internal consistency for ABC subscales was moderate to high. The total ABC score, which is interdependent with subscales (e.g., Irritability, Social Withdrawal) of the ABC, was significantly correlated with the CBCL-total (r= .73) and AuBC-total (r= .71) scores. Subscales of the ABC revealed significant differences between diagnostic groups. ABC Total, and the Irritability and Hyperactivity subscale scores, were significantly higher in children with externalizing disorders; the Lethargy/Social Withdrawal and Stereotypic Behavior subscale scores were significantly higher in toddlers with autism. The ABC appears to be capable of discriminating several syndromes, such as disruptive behavior disorders and autism in early childhood.

Standardised Observation Analogue Procedure (SOAP) for assessing parent and child behaviours in clinical trials.

BACKGROUND: Observational measures of parent and child behaviours have a long history in child psychiatric and psychological intervention research, including the field of autism and developmental disability. We describe the development of the Standardised Observational Analogue Procedure (SOAP) for the assessment of parent-child behaviour before and after a structured parent training program for children with pervasive developmental disorders (PDD). We report on the use of this procedure in a pilot study of 12 participants with PDD. RESULTS: Inter-rater reliability across behaviours coded ranged from 75-100% agreement. Blindly scored observations of behaviour showed medium effect sizes for changes in inappropriate child behaviour. Analyses of baseline scores revealed a moderate positive correlation between inappropriate child behaviours as measured in all four SOAP conditions and parent ratings of child noncompliance (r(s) = .66, p < .05). By contrast, the correlations of SOAP scores with parent ratings of irritability was lower (r(s) = .40, p >.05). CONCLUSIONS: As our treatment targeted compliance, these preliminary results suggest that the SOAP provides a valid measure of noncompliant behaviour in children with PDD and is sensitive to treatment effects on inappropriate child behaviours.

Pharmacogenetics of Metformin for Medication-Induced Weight Gain in Autism Spectrum Disorder.

Objectives: We recently found that metformin attenuated weight gain due to mixed dopamine and serotonin receptor antagonists, commonly termed atypical antipsychotics, in children and adolescents with autism spectrum disorder (ASD). Previous studies have found that genetic variation predicts response to metformin in diabetes. In this study, we aimed to assess whether response to metformin for weight gain in this population is associated with variants in five genes previously implicated in metformin response in diabetes. Methods: Youth with ASD who experienced significant weight gain while taking mixed receptor antagonist medications were randomly assigned to metformin or placebo for 16 weeks, followed by open-label metformin treatment for 16 weeks. In the 53 participants with available DNA samples, we used a linear, mixed model analysis to assess response in the first 16 weeks of metformin treatment, whether in the randomized or open-label period, based upon genotypes at polymorphisms in five genes previously associated with metformin response in diabetes: ATM, SLC2A2, MATE1, MATE2, and OCT1. Results: In the primary analysis, both ATM and OCT1 showed significant effects of genotype on change in body mass index z-scores, the primary outcome measure, during the first 16 weeks of treatment with metformin. No other polymorphism showed a significant difference. Conclusion: As has been shown for metformin treatment in diabetes, genetic variation may predict response to metformin for weight gain in youth with ASD treated with mixed receptor antagonists. Further work is needed to replicate these findings and evaluate whether they can be used prospectively to improve outcomes.

Development of the Parent-Rated Anxiety Scale for Youth With Autism Spectrum Disorder.

OBJECTIVE: Anxiety is common in youth with autism spectrum disorder (ASD). There is no accepted outcome measure for anxiety in this population. METHOD: Following a series of focus groups with parents of youth with ASD, we generated 72 items (scored 0-3). Parents of 990 youth with ASD (aged 5-17 years; 80.8% male) completed an online survey. Factor analysis and item response theory analyses reduced the content to a single factor with 25 items. Youth with at least mild anxiety (n = 116; aged 5-17 years; 79.3% male) participated in a comprehensive clinical assessment to evaluate the validity and reliability of the 25-item Parent-Rated Anxiety Scale for ASD (PRAS-ASD). RESULTS: In the online sample, the mean PRAS-ASD score was 29.04 ± 14.9 (range, 0-75). The coefficient α was 0.93. The item response theory results indicated excellent reliability across a wide range of scores with low standard errors. In the clinical sample (n = 116), the PRAS-ASD mean was 31.0 ± 15.6 (range, 1-65). Pearson correlations with parent ratings of ASD symptom severity, repetitive behavior, and disruptive behavior ranged 0.33 to 0.66, supporting divergent validity of the PRAS-ASD. Pearson correlation with a parent-rated measure of anxiety used in the general pediatric population of 0.83 supported convergent validity. A total of 40 participants (32 boys, 8 girls; mean age, 11.9 ± 3.4 years) returned at time 2 (mean, 12.2 days) and time 3 (mean, 24.2 days). Intraclass correlation showed test-retest reliabilities of 0.88 and 0.86 at time 2 and time 3, respectively. CONCLUSION: The 25-item PRAS-ASD is a reliable and valid scale for measuring anxiety in youth with ASD.

Efficacy and safety of memantine in children with autism spectrum disorder: Results from three phase 2 multicenter studies.

Three phase 2 trials were conducted to assess the efficacy and long-term safety of weight-based memantine extended release (ER) treatment in children with autism spectrum disorder. MEM-MD-91, a 50-week open-label trial, identified memantine extended-release treatment responders for enrollment into MEM-MD-68, a 12-week randomized, double-blind, placebo-controlled withdrawal trial. MEM-MD-69 was an open-label extension trial in which participants from MEM-MD-68, MEM-MD-91, and open-label trial MEM-MD-67 were treated ⩽48 weeks with memantine extended release. In MEM-MD-91, 517 (59.6%) participants were confirmed Social Responsiveness Scale responders at week 12; mean Social Responsiveness Scale total raw scores improved two to three times a minimal clinically important difference of 10 points. In MEM-MD-68, there was no difference between memantine and placebo on the primary efficacy parameter, the proportion of patients with a loss of therapeutic response (defined as ⩾10-point increase from baseline in Social Responsiveness Scale total raw score). MEM-MD-69 exploratory analyses revealed mean standard deviation improvement in Social Responsiveness Scale total raw score of 32.4 (26.4) from baseline of the first lead-in study. No new safety concerns were evident. While the a priori-defined efficacy results of the double-blind trial were not achieved, the considerable improvements in mean Social Responsiveness Scale scores from baseline in the open-label trials were presumed to be clinically important.

Parent-rated anxiety symptoms in children with pervasive developmental disorders: frequency and association with core autism symptoms and cognitive functioning.

BACKGROUND: In addition to the core symptoms, children with Pervasive Developmental Disorders (PDD) often exhibit other problem behaviors such as aggression, hyperactivity, and anxiety, which can contribute to overall impairment and, therefore, become the focus of clinical attention. Limited data are available on the prevalence of anxiety in these children. We examined frequency and correlates of parent-rated anxiety symptoms in a large sample of children with PDD. METHODS: The goals of this study were to examine the frequency and correlates of parent-rated anxiety symptoms in a sample of 171 medication-free children with PDD who participated in two NIH-funded medication trials. Twenty items of the Child and Adolescent Symptom Inventory (CASI) were used to measure anxiety. RESULTS: Forty three percent of the total sample met screening cut-off criteria for at least one anxiety disorder. Higher levels of anxiety on the 20-item CASI scale were associated with higher IQ, the presence of functional language use, and with higher levels of stereotyped behaviors. In children with higher IQ, anxiety was also associated with greater impairment in social reciprocity. CONCLUSION: Anxiety is common in PDD and warrants consideration in clinical evaluation and treatment planning. This study suggests that parent ratings could be a useful source of information about anxiety symptoms in this population. Some anxiety symptoms such as phobic and social anxiety may be closer to core symptoms of PDD. Further efforts to validate tools to ascertain anxiety are needed, as are studies to empirically test approaches to treat anxiety in PDD.

Treatment of inattention, overactivity, and impulsiveness in autism spectrum disorders.

We reviewed the recent literature on medicines used to manage inattention, impulsiveness, and overactivity in children with pervasive developmental disorders (autistic disorder, pervasive developmental disorder not otherwise specified, Asperger's disorder) using computer searches of pharmacologic studies. A substantial number of reports were identified and summarized. The literature tends to be dominated by uncontrolled studies, although the number of controlled trials is growing. Findings are described for psychostimulants, noradrenergic reuptake inhibitors, antipsychotics, alpha adrenergic agonists, antidepressants, anxiolytics, cholinesterase inhibitors, N-methyl-D-aspartate receptor blockers, and antiepileptic mood stabilizers. Evidence for a positive effect is strongest for psychostimulants, noradrenergic reuptake inhibitors, antipsychotics, and alpha adrenergic agonists. Evidence for efficacy seems weakest for newer antidepressants, anxiolytics, and mood stabilizers.

Clinical Relevance Versus Statistical Significance: Aman and Colleagues Respond to Editorial.

We would like to respond to the thought-provoking editorial by Dr. Jon McClellan1 regarding our article "Clinical Implications from the Treatment of Severe Childhood Aggression (TOSCA) Study: A Re-Analysis and Integration of Findings," published in the December 2017 issue of JAACAP.2 We address some issues on which we partially disagree, and comment on convergence of opinion.

Dr. Handen et al. Reply.

We thank Dr. Higdon et al. for their interest in our article on metformin and children with autism spectrum disorders (ASD) and for providing information about the MOBILITY study (a Patient-Centered Outcomes Research Institute (PCORI)-funded pragmatic clinical trial to examine the relative effectiveness of metformin plus healthy lifestyle instruction versus healthy lifestyle instruction alone).1 In our October 2017 article,2 we reported the results of a 16-week open-label extension study of a group of 61 children and adolescents with ASD prescribed second-generation antipsychotic medications (SGAs) who previously participated in a randomized controlled trial (RCT) of metformin for management of weight gain. Although Higdon et al. indicated that our study results were encouraging, they believed that the conclusion of the accompanying JAACAP editorial3 stating metformin be considered as an adjunct treatment for any child who is overweight and prescribed SGAs was premature. Instead, they recommended that the results of their current pragmatic trial for children with bipolar disorder (which includes some children with ASD and intellectual disability) would better provide information on relevant moderators and mediators of metformin's effects. Such information would be of use to clinicians in determining whether to prescribe metformin to their patients or to focus on lifestyle changes (or a combination of the 2).

Testing genetic modifiers of behavior and response to atomoxetine in autism spectrum disorder with ADHD.

BACKGROUND: Frequent non-pathogenic genetic variants may act as moderators of phenotypic severity for complex disorders such as autism spectrum disorder (ASD). We previously identified polymorphisms affecting mRNA expression of candidate genes, including tryptophan hydroxylase 2 (TPH2), dopamine beta hydroxylase (DBH), and dopamine transporter (DAT, SLC6A3). METHOD: We compare genotypes and (1) clinical response to atomoxetine, (2) scores from the Autism Diagnostic Interview-Revised (ADI-R), and (3) severity of Attention Deficit Hyperactivity Disorder (ADHD) symptoms in a cohort of patients with ASD from multiple study sites. RESULTS: There was no association between CYP2D6 metabolizer status and atomoxetine response. TPH2 rs7305115 genotype was associated with ADI-R Restrictive/Repetitive Behavior score (p=0.03). DBH rs1611115 genotype was associated with ADI-R Social score (p=0.002) and Restrictive/Repetitive Behavior score (p=0.04). The DAT intron 8 5/6 repeat was associated with ADHD symptoms (ABC Hyperactivity p=0.01 and SNAP ADHD p=0.03), replicating a previous finding. CONCLUSIONS: We find associations between ASD phenotypes and regulatory variants in catecholamine biosynthesis genes. This work may help guide future genetics studies related to ASD.