John Wray

The prevalence of autism in Australia. Can it be established from existing data

Aim:  To assess whether existing data collection mechanisms can provide accurate and sufficient information about the prevalence of autism in Australia.

Utilization of alternative therapies in attention‐deficit hyperactivity disorder

Objective: To identify the prevalence of use, the referral patterns and the perceived benefit of alternative therapy in children with attention‐deficit hyperactivity disorder (ADHD).

Towards a molecular characterization of autism spectrum disorders: an exome sequencing and systems approach

The hypothetical ‘AXAS’ gene network model that profiles functional patterns of heterogeneous DNA variants overrepresented in autism spectrum disorder (ASD), X-linked intellectual disability, attention deficit and hyperactivity disorder and schizophrenia was used in this current study to analyze whole exome sequencing data from an Australian ASD cohort. An optimized DNA variant filtering pipeline was used to identify loss-of-function DNA variations. Inherited variants from parents with a broader autism phenotype and de novo variants were found to be significantly associated with ASD. Gene ontology analysis revealed that putative rare causal variants cluster in key neurobiological processes and are overrepresented in functions involving neuronal development, signal transduction and synapse development including the neurexin trans-synaptic complex. We also show how a complex gene network model can be used to fine map combinations of inherited and de novo variations in families with ASD that converge in the L1CAM pathway. Our results provide an important step forward in the molecular characterization of ASD with potential for developing a tool to analyze the pathogenesis of individual affected families.

Brief Report: Do the Nature of Communication Impairments in Autism Spectrum Disorders Relate to the Broader Autism Phenotype in Parents?

Extensive empirical evidence indicates that the lesser variant of Autism Spectrum Disorders (ASD) involves a communication impairment that is similar to, but milder than, the deficit in clinical ASD. This research explored the relationship between the broader autism phenotype (BAP) among parents, an index of genetic liability for ASD, and proband communication difficulties. ASD probands with at least one BAP parent (identified using the Autism Spectrum Quotient) had greater structural and pragmatic language difficulties (assessed using the Children’s Communication Checklist-2) than ASD probands with no BAP parent. This finding provides support for the position that genetic liability for ASD is associated with increased communication difficulties across structural and pragmatic domains.

Maternal phenylketonuria in Western Australia: Pregnancy outcomes and developmental outcomes in offspring

Objective:  To examine the outcomes of phenylketonuric (PKU) pregnancies in Western Australia including birth characteristics and cognitive and behavioural outcomes in offspring.

No association between early gastrointestinal problems and autistic-like traits in the general population.

Aim  The aim of this study was to determine whether gastrointestinal problems in early childhood relate to autistic‐like traits in a general population sample.

Evidence of a reduction over time in the behavioral severity of autistic disorder diagnoses

The increasing prevalence of Autism Spectrum Disorders (ASD) may in part be due to a shift in the diagnostic threshold that has led to individuals with a less severe behavioral phenotype receiving a clinical diagnosis. This study examined whether there were changes over time in the qualitative and quantitative phenotype of individuals who received the diagnosis of Autistic Disorder. Data were from a prospective register of new diagnoses in Western Australia (n = 1252). From 2000 to 2006, we examined differences in both the percentage of newly diagnosed cases that met each criterion as well as severity ratings of the behaviors observed (not met, partially met, mild/moderate and extreme). Linear regression determined there was a statistically significant reduction from 2000 to 2006 in the percentage of new diagnoses meeting two of 12 criteria. There was also a reduction across the study period in the proportion of new cases rated as having extreme severity on six criteria. There was a reduction in the proportion of individuals with three or more criteria rated as extreme from 2000 (16.0%) to 2006 (1.6%), while percentage of new cases with no “extreme” rating on any criteria increased from 58.5% to 86.6% across the same period. This study provides the first clear evidence of a reduction over time in the behavioral severity of individuals diagnosed with Autistic Disorder during a period of stability in diagnostic criteria. A shift toward diagnosing individuals with less severe behavioral symptoms may have contributed to the increasing prevalence of Autistic Disorder diagnoses. Autism Res 2017, 10: 179–187.

High use of complementary and alternative medication among children with autism is not associated with the severity of core symptoms

Abstract Background: Complementary and alternative medicine (CAM) is commonly used by individuals with autism spectrum disorder (ASD). No study has examined individual, family and clinical characteristics associated

Obesity and associated factors in youth with an autism spectrum disorder

Weight status on children and youth with autism spectrum disorder is limited. We examined the prevalence of overweight/obesity in children and youth with autism spectrum disorder, and associations between weight status and range of factors. Children and youth with autism spectrum disorder aged 2–16 years (n = 208) and their parents participated in this study. Body mass index was calculated using the Centers for Disease Control and Prevention growth charts and the International Obesity Task Force body mass index cut-offs. The Autism Diagnostic Observation Schedule was administered. Parents completed questionnaires about socio-demographics, diagnosed comorbidities, sleep disturbances, social functioning and medication of youth with autism spectrum disorder. The prevalence of overweight/obesity in participants with autism spectrum disorder was 35%. One quarter of obese children and youth (25.6%) had obese parents. There was a significant association between children and youth’s body mass index and maternal body mass index (r = 0.25, n = 199, p < 0.001). The gender and age, parental education, family income, ethnicity, autism spectrum disorder severity, social functioning, psychotropic and complementary medication use of children and youth with autism spectrum disorder were not statistically associated with their weight status. Findings suggest the need for clinical settings to monitor weight status of children and youth with autism spectrum disorder in a bid to manage or prevent overweight/obesity in this population. Incorporating a family system approach to influence health behaviours among children and youth with autism spectrum disorder especially for specific weight interventions is warranted and should be further explored.

Cytokine levels and associations with symptom severity in male and female children with autism spectrum disorder

BackgroundAutism spectrum disorders (ASDs) are complex, pervasive, and heterogeneous neurodevelopmental conditions with varying trajectories, significant male bias and largely unknown etiology. However, an understanding of the biological mechanisms driving pathophysiology is evolving. Immune system aberrations, as identified through cytokine profiles, are believed to have a role in ASD. Altered cytokine levels may facilitate identification of ASD subtypes as well as provide biological markers of response to effective treatments. Research exploring the relationship between cytokine profiles and ASD symptoms is, however, in its infancy. The objective of this study was to explore relationships between cytokine levels and the severity of ASD and other clinical traits.MethodsMultiplex assay techniques were used to measure levels of 27 cytokines in plasma samples from a cohort of 144 children diagnosed with ASD.ResultsOverall, results showed a significant negative association between platelet-derived growth factor (PDGF)-BB, and the severity of ASD symptoms. Furthermore, a significant interaction with sex suggested a different immune profile for females compared to males. ASD symptom severity was negatively associated with levels of 4 cytokines, IL-1β, IL-8, MIP-1β, and VEGF, in females, but not in males.ConclusionsResults of the present study suggest that an altered cytokine response or profile is associated with the severity of ASD-related symptoms, with sex a potential modifier of this relationship. Further research in larger populations which recognizes the importance of sex comparisons and longitudinal assessments are now required to extend and further describe the role of the immune system in ASD.