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Diets of children and adolescents on the autism spectrum often differ when compared to their non-autistic peers. Most dietary studies have been limited by small sample sizes and rarely assess the heterogeneity of autism. Addressing this gap, this study compared the anthropometrics, dietary composition, dietary quality, and food variety of 154 Australian children and adolescents on the spectrum and 213 non-autistic children (71 siblings and 142 unrelated controls). Beyond the case-control approach, within-group comparisons assessed the influence of autism clinical presentations and sensory processing styles on body mass index (BMI) and measures of dietary intake among those on the spectrum. In this word first study of diet that included between-group comparisons with non-autistic peers (siblings and an unrelated comparison group) and within-autism group comparisons, we found that children on the spectrum consumed limited variety and lower quality of food and non-autistic siblings also ate comparably higher levels of energy-dense, nutrient poor food, and less diary. This may be due to autistic traits influencing family's diets or shared sensory sensitivities driving dietary intake. Within the autism group, higher autistic traits were associated with lower BMIs and a specific dietary pattern higher in simple carbohydrates and lower in unprocessed protein. Contrastingly, greater sensitivity to sensory stimuli was associated with a healthier diet. Increased age was linked to more varied diets but also diets higher in saturated fats and energy-dense, nutrient poor foods. Overall, this research highlights that potential mediators of dietary intake, such as familial influences, autistic traits, sensory processing styles, age and sex, need to be considered when assessing diet in the autistic population. LAY SUMMARY: In this study of dietary differences linked to autism, children, and teenagers on the spectrum ate fewer different foods and were less likely to eat recommended amounts of fruits and vegetables when compared to non-autistic siblings and unrelated children and teenagers. There were also family differences, in that those on the spectrum and their siblings ate more unhealthy foods and less dairy. Among those on the spectrum, dietary differences were linked to age, sex, autistic traits and sensory processing styles.

Background Autism spectrum disorder (ASD) is a complex neurodevelopmental condition whose biological basis is yet to be elucidated. The Australian Autism Biobank (AAB) is an initiative of the Cooperative Research Centre for Living with Autism (Autism CRC) to establish an Australian resource of biospecimens, phenotypes and genomic data for research on autism. Methods Genome-wide single-nucleotide polymorphism genotypes were available for 2,477 individuals (after quality control) from 546 families (436 complete), including 886 participants aged 2 to 17 years with diagnosed (n = 871) or suspected (n = 15) ASD, 218 siblings without ASD, 1,256 parents, and 117 unrelated children without an ASD diagnosis. The genetic data were used to confirm familial relationships and assign ancestry, which was majority European (n = 1,964 European individuals). We generated polygenic scores (PGS) for ASD, IQ, chronotype and height in the subset of Europeans, and in 3,490 unrelated ancestry-matched participants from the UK Biobank. We tested for group differences for each PGS, and performed prediction analyses for related phenotypes in the AAB. We called copy-number variants (CNVs) in all participants, and intersected these with high-confidence ASD- and intellectual disability (ID)-associated CNVs and genes from the public domain. Results The ASD (p = 6.1e−13), sibling (p = 4.9e−3) and unrelated (p = 3.0e−3) groups had significantly higher ASD PGS than UK Biobank controls, whereas this was not the case for height—a control trait. The IQ PGS was a significant predictor of measured IQ in undiagnosed children (r = 0.24, p = 2.1e−3) and parents (r = 0.17, p = 8.0e−7; 4.0% of variance), but not the ASD group. Chronotype PGS predicted sleep disturbances within the ASD group (r = 0.13, p = 1.9e−3; 1.3% of variance). In the CNV analysis, we identified 13 individuals with CNVs overlapping ASD/ID-associated CNVs, and 12 with CNVs overlapping ASD/ID/developmental delay-associated genes identified on the basis of de novo variants. Limitations This dataset is modest in size, and the publicly-available genome-wide-association-study (GWAS) summary statistics used to calculate PGS for ASD and other traits are relatively underpowered. Conclusions We report on common genetic variation and rare CNVs within the AAB. Prediction analyses using currently available GWAS summary statistics are largely consistent with expected relationships based on published studies. As the size of publicly-available GWAS summary statistics grows, the phenotypic depth of the AAB dataset will provide many opportunities for analyses of autism profiles and co-occurring conditions, including when integrated with other omics datasets generated from AAB biospecimens (blood, urine, stool, hair).

There is limited evidence base regarding mental health issues in people with intellectual disability (ID), and hence, findings from the general population are often applied to ID groups. Available evidence suggests that individuals with ID experience higher rates of mental health disorders than the general population, although findings are mixed with regard to the determinants of this increased prevalence. Further, the consequences of this comorbidity for individuals, families, and the wider community are often overlooked including the multiple challenges in identifying and managing these concerns. Accurate diagnosis and effective intervention are currently hindered by factors including the applicability of standardized psychiatric classification systems, gaps in service delivery models and access to such services, as well as unmet training needs. It is critical that further research is carried out to examine the specific challenges facing individuals with ID along with facilitating appropriate mental health services to individuals with ID.

There is increasing interest in the potential contribution of the gut microbiome to autism spectrum disorder (ASD). However, previous studies have been underpowered and have not been designed to address potential confounding factors in a comprehensive way. We performed a large autism stool metagenomics study (n = 247) based on participants from the Australian Autism Biobank and the Queensland Twin Adolescent Brain project. We found negligible direct associations between ASD diagnosis and the gut microbiome. Instead, our data support a model whereby ASD-related restricted interests are associated with less-diverse diet, and in turn reduced microbial taxonomic diversity and looser stool consistency. In contrast to ASD diagnosis, our dataset was well powered to detect microbiome associations with traits such as age, dietary intake, and stool consistency. Overall, microbiome differences in ASD may reflect dietary preferences that relate to diagnostic features, and we caution against claims that the microbiome has a driving role in ASD.

BACKGROUND Previous research suggests that parents raising a child with autism experience higher levels of psychological distress than parents of typically developing children and parents of children with other developmental disorders. Little is known, however, about the intersection between the effects of socioeconomic status (SES) on the wellbeing and sense of parental competency of parents of pre-schoolers with autism and how it relates to child symptom severity. AIM To examine the relationship between their child’s symptom severity, SES, as measured by neighbourhood advantage and occupational status, on the psychological wellbeing and perceived parenting competence among parents of preschoolers with autism. METHODS Parents of 117 preschool-aged children with a diagnosis of autism spectrum disorder (ASD), 107 mothers and 54 fathers, completed questionnaires about their child’s symptoms of ASD and functioning, their own perceptions of their wellbeing and parental competence on entry to an early intervention program in Sydney, Australia. Parents also provided demographic information pertaining to their occupation, level of education attained and address (postcode). All children were also assessed for their severity of symptoms using the Autism Diagnostic Observation Schedule. The Australian Socioeconomic Index of occupational status as a measure of familial SES and the Index of Relative Socio-economic Advantage and Disadvantage as a measure of neighbourhood advantage were used to examine the impact of SES on parental sense of competence and wellbeing. RESULTS Compared to normative populations, both mothers and fathers in our sample reported significantly higher levels of parenting sense of efficacy but lower levels of interest in the parenting role. Mothers also displayed higher levels of satisfaction. Both mothers and fathers displayed higher levels of depression than normative populations with mothers also reporting greater levels of stress and anxiety. Child symptom severity was associated with maternal parenting competency with these relationships amplified among mothers with higher familial SES and who lived in areas of greater neighbourhood advantage. Increased adaptive functioning was associated with better maternal wellbeing, particularly among mothers who lived in areas of greater neighbourhood advantage. Contrastingly, paternal parenting competence was generally not influenced by child adaptive functioning or symptom severity, although for those in higher familial SES brackets, children’s symptom severity and maladaptive symptoms were negatively related to paternal sense of parenting efficacy. There was a trend towards moderate relationships between lower familial SES and greater depression, stress and anxiety among fathers, but no relationship with their child’s ASD symptom severity or functioning. CONCLUSION SES differentially impacts wellbeing and sense of parenting competence and its relationship to the impact of child symptoms for mothers and fathers of preschoolers with autism.