The effect of functioning on Quality of Life Inventory-Disability measured quality of life is not mediated or moderated by parental psychological distress.

PURPOSE: The measurement of quality of life (QOL) in children with intellectual disability often relies upon proxy report via caregivers. The current study investigated whether caregiver psychological distress mediates or moderates the effects of impairment on their ratings of QOL in children with intellectual disability. METHODS: Caregivers of 447 children with an intellectual disability reported their child's day-to-day functioning, their own psychological distress using the Kessler Psychological Distress Scale, and the Quality of Life Inventory-Disability (QI-Disability), a measure of QOL for proxy report of a child's observable behaviours that indicate quality of life. Linear regression was used to assess the effects of the child's functional abilities on their QI-Disability score and causal mediation analysis to estimate the extent to which these effects were mediated by caregivers' psychological distress. RESULTS: A minority of caregivers (n = 121, 27.1%) reported no psychological distress. Lower day-to-day functional abilities, such as being fully dependent on others to manage their personal needs were associated with lower total QOL scores. There was no significant mediation effect of caregiver psychological distress on the association between child functioning and total QOL scores. Moderation analyses revealed small and largely nonsignificant interaction coefficients, indicating that caregiver psychological distress did not influence the strength of the relationship between child functioning and total QOL scores. CONCLUSION: Caregiver psychological distress did not mediate or moderate the relationship between the level of functional abilities and QOL in children with intellectual disability. QI-Disability measured observable child behaviours which may reduce the influence of caregiver factors on the accurate measure of QOL for children with intellectual disability.

Social impairments in autism spectrum disorder are related to maternal immune history profile.

Maternal immune activation has been highlighted as a factor that might increase the risk and severity of autism spectrum disorder (ASD) in children. Preclinical animal evidence shows that immune activation in mothers during pregnancy causes ASD-like behavioural traits in offspring. To this point, there has been no investigation of whether immune system activation in human mothers during pregnancy is associated with more severe symptoms in children with ASD. In this study, data from an existing ASD cohort (N=220) were analysed to investigate whether immune conditions in the mother were associated with greater severity of autism-related symptoms. Results showed that children whose mothers reported a history of immune activation (allergies and asthma) had significantly higher scores on the Social Responsiveness Scale (SRS; P=0.016), suggesting more severe social impairment symptoms in these children. This increasing severity of social impairment symptoms was further shown on the SRS cognition (P=0.007) and mannerisms (P=0.002) subscales. While immune history was associated with an increase in the severity of social impairment symptoms, history of autoimmune conditions in the mother did not have any effect in this cohort. To the best of our knowledge, this study is the first to show an association between immune activation history in the mother and increased ASD symptom severity in children with ASD. These findings support the idea of an immune system-mediated subtype in ASD, where the immune history of the mother may be an important factor.

Does otitis media in early childhood affect later behavioural development? Results from the Western Australian Pregnancy Cohort (Raine) Study.

OBJECTIVES: To examine the relationship between early life episodes of otitis media and later behavioural development with adjustment for confounders. DESIGN: Longitudinal cohort study. SETTING: The Western Australian Pregnancy Cohort (Raine) Study recruited 2900 pregnant women from King Edward Memorial Hospital (KEMH) in Perth, Western Australia, between 1989 and 1991. PARTICIPANTS: Data from the children born were collected at both the Year 3 and Year 5 follow-up. At Year 3, n = 611 were diagnosed with recurrent otitis media through parent-report and clinical examination. At Year 5, n = 299 were considered exposed to otitis media based upon tympanometry results. MAIN OUTCOME MEASURES: Performance in the Child Behaviour Checklist (CBCL), a questionnaire completed by the primary caregiver at Year 10. RESULTS: Significant associations were found between recurrent otitis media at Year 3 and internalising behaviours (P = .011), and the somatic (P = .011), withdrawn (P = .014), attention (P = .003) and thought problems domains (P = .021), and the total CBCL score (P = .010). A significant association was also found between exposure to otitis media at Year 5 and externalising behaviours (P = .026). CONCLUSIONS: A modest association was seen between recurrent otitis media at Year 3 and exposure to otitis media at Year 5 and a number of behaviour domains at Year 10.

Duration of general anaesthetic exposure in early childhood and long-term language and cognitive ability.

BACKGROUND: The anaesthetic dose causing neurotoxicity in animals has been evaluated, but the relationship between duration of volatile anaesthetic (VA) exposure and neurodevelopment in children remains unclear. METHODS: Data were obtained from the Western Australian Pregnancy Cohort (Raine) Study, with language (Clinical Evaluation of Language Fundamentals: Receptive [CELF-R] and Expressive [CELF-E] and Total [CELF-T]) and cognition (Coloured Progressive Matrices [CPM]) assessed at age 10 yr. Medical records were reviewed, and children divided into quartiles based on total VA exposure duration before age three yr. The association between test score and exposure duration quartile was evaluated using linear regression, adjusting for patient characteristics and comorbidity. RESULTS: Of 1622 children with available test scores, 148 had documented VA exposure and were split into the following quartiles: ≤25, >25 to ≤35, >35 to ≤60 and >60 min. Compared with unexposed children, CELF-T scores for children in the first and second quartiles did not differ, but those in the third and fourth quartiles had significantly lower scores ([3 rd quartile - Unexposed] -5.3; 95% confidence interval [CI], (-10.2 - -0.4), [4 th quartile - Unexposed] -6.2; 95% CI, (-11.6 - -0.9). CELF-E showed similar findings, but significant differences were not found in CELF-R or CPM for any quartile. CONCLUSIONS: Children with VA exposures ≤35 min did not differ from unexposed children, but those with exposures >35 min had lower total and expressive language scores. It remains unclear if this is a dose-response relationship, or if children requiring longer exposures for longer surgeries have other clinical reasons for lower scores.

Protective benefit of predominant breastfeeding against otitis media may be limited to early childhood: results from a prospective birth cohort study.

OBJECTIVES: To examine the long-term effects of predominant breastfeeding on incidence of otitis media. DESIGN: Prospective birth cohort study. SETTING: The West Australian Pregnancy Cohort (Raine) Study recruited 2900 mothers through antenatal clinics at the major tertiary obstetric hospital in Perth, Western Australia, between 1989 and 1992. PARTICIPANTS: In total, 2237 children participated in a 6-year cohort follow-up, and a subset of 1344 were given ear and hearing assessments. MAIN OUTCOME MEASURES: OM diagnosis at 6 years of age (diagnosed by low-compliance tympanograms, 0-0.1 mmho). This was compared to OM diagnosed at the 3-year cohort follow-up using parent-report measures. Main exposure measures were duration of predominant breastfeeding (defined as the age other milk was introduced) and duration of partial (any) breastfeeding (defined as the age breastfeeding was stopped). RESULTS: There was a significant, independent association between predominant breastfeeding (OR = 1.33 [1.04, 1.69]; P = 0.02) and OM, and breastfeeding duration (OR = 1.35 [1.08, 1.68]; P = 0.01) with OM at 3 years of age. However, at 6 years of age, this relationship was no longer statistically significant (predominant breastfeeding OR = 0.78 [0.48, 1.06]; P = 0.09; duration of breastfeeding, OR = 1.34 [0.81, 2.23]; P = 0.25). CONCLUSIONS: Our findings are in line with a number of epidemiological studies which show a positive association between breastfeeding and OM in early childhood. However, the long-term follow-up of these children revealed that by 6 years of age, there was no significant influence of breastfeeding on presence of OM. These results suggest that the protective effect of predominant breastfeeding for at least 6 months does not extend to school-age children, where other social and environmental factors may be stronger predictors of OM.

Difficulties in developmental follow-up of preterm neonates in a randomised-controlled trial of Bifidobacterium breve M16-V - Experience from Western Australia.

BACKGROUND: Probiotics may be neuroprotective for preterm neonates due to their anti-inflammatory effects and ability to facilitate nutrition. AIM: To assess long-term effects of early probiotic supplementation on neuropsychological development in preterm infants. STUDY DESIGN: Follow up study. SUBJECTS: Children at age 3 to 5 years who had participated as preterm infants (<33 week) in the randomised controlled trial. OUTCOMES: Primary: Continuous early learning composite measure derived from the Mullen's Scale of Early Learning (MSEL). Other outcomes were assessed by the Developmental, Dimensional and Diagnostic Interview, Developmental NEuroPSYchological assessment-2nd Edition, Parental questionnaires using children's communication checklist-2nd edition, social responsiveness scale, and Vineland Adaptive Behavioural Scales-2nd edition. MEASURES: Continuous scores derived from all the measures. RESULTS: 67 children of the 159 participants (42%) (Probiotic: 36/79, Placebo: 31/80) were followed-up for at least one neuropsychological assessment. All six assessments were completed in 18/31 (58.1%) of the control vs. 11/36 (30.6%) probiotic group children. Multivariable analysis of MSEL composite score showed no evidence of probiotic effect univariately, or after adjustment for gestation, intrauterine growth restriction, Apgar <7 at 5 min and age at assessment (adjusted mean effect in probiotic group: -2.7, 95% CI -8.5-3.0, p = 0.349). CONCLUSION: There was no significant effect on neurodevelopment of children assessed at the age of 3 to 5 years who participated as preterm neonates in the RCT of B. breve M-16V. The validity of these results is limited by the reduced sample size due to high rate of loss to follow up.

Lack of replication for the myosin-18B association with mathematical ability in independent cohorts.

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance. We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible. We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities.

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.

Autism spectrum disorder in children born preterm-role of exposure to perinatal inflammation.

Autism Spectrum Disorder (ASD) is the collective term for neurodevelopmental disorders characterized by qualitative impairments in social interaction, communication, and a restricted range of activities and interests. Many countries, including Australia, have reported a dramatic increase in the number of diagnoses over the past three decades, with current prevalence of ASD at 1 in every 110 individuals (~1%). The potential role for an immune-mediated mechanism in ASD has been implicated by several studies, and some evidence suggests a potential link between prenatal infection-driven inflammation and subsequent development of ASD. Furthermore, a modest number of contemporary studies have reported a markedly increased prevalence of ASD in children born preterm, who are at highest risk of exposure to perinatal inflammation. However, the mechanisms that underpin the susceptibility to infection-driven inflammation during pregnancy and risk of preterm birth, and how these intersect with the subsequent development of ASD in the offspring, is not understood. This review aims to summarize and discuss the potential mechanisms and evidence for the role of prenatal infection on the central nervous system, and how it may increase the susceptibility for ASD pathogenesis in children born preterm.

Analysis of dyslexia candidate genes in the Raine cohort representing the general Australian population.

Several genes have been suggested as dyslexia candidates. Some of these candidate genes have been recently shown to be associated with literacy measures in sample cohorts derived from the general population. Here, we have conducted an association study in a novel sample derived from the Australian population (the Raine cohort) to further investigate the role of dyslexia candidate genes. We analysed markers, previously reported to be associated with dyslexia, located within the MRPL19/C2ORF3, KIAA0319, DCDC2 and DYX1C1 genes in a sample of 520 individuals and tested them for association with reading and spelling measures. Association signals were detected for several single nucleotide polymorphisms (SNPs) within DYX1C1 with both the reading and spelling tests. The high linkage disequilibrium (LD) we observed across the DYX1C1 gene suggests that the association signal might not be refined by further genetic mapping.

CNTNAP2 variants affect early language development in the general population.

Early language development is known to be under genetic influence, but the genes affecting normal variation in the general population remain largely elusive. Recent studies of disorder reported that variants of the CNTNAP2 gene are associated both with language deficits in specific language impairment (SLI) and with language delays in autism. We tested the hypothesis that these CNTNAP2 variants affect communicative behavior, measured at 2 years of age in a large epidemiological sample, the Western Australian Pregnancy Cohort (Raine) Study. Singlepoint analyses of 1149 children (606 males and 543 females) revealed patterns of association which were strikingly reminiscent of those observed in previous investigations of impaired language, centered on the same genetic markers and with a consistent direction of effect (rs2710102, P = 0.0239; rs759178, P = 0.0248). On the basis of these findings, we performed analyses of four-marker haplotypes of rs2710102-rs759178-rs17236239-rs2538976 and identified significant association (haplotype TTAA, P = 0.049; haplotype CGAG, [corrected] P = .0014). Our study suggests that common variants in the exon 13-15 region of CNTNAP2 influence early language acquisition, as assessed at age 2, in the general population. We propose that these CNTNAP2 variants increase susceptibility to SLI or autism when they occur together with other risk factors.