1. Charman T, Jones CR, Pickles A, Simonoff E, Baird G, Happe F. {{Defining the cognitive phenotype of autism}}. {Brain Res} (Oct 25)
Although much progress has been made in determining the cognitive profile of strengths and weaknesses that characterise individuals with autism spectrum disorders (ASDs), there remain a number of outstanding questions. These include how universal strengths and deficits are; whether cognitive subgroups exist; and how cognition is associated with core autistic behaviours, as well as associated psychopathology. Several methodological factors have contributed to these limitations in our knowledge, including: small sample sizes, a focus on single domains of cognition, and an absence of comprehensive behavioural phenotypic information. To attempt to overcome some of these limitations, we assessed a wide range of cognitive domains in a large sample (N=100) of 14 to 16year old adolescents with ASDs who had been rigorously behaviourally characterised. In this review, we will use examples of some initial findings in the domains of perceptual processing, emotion processing and memory, both to outline different approaches we have taken to data analysis and to highlight the considerable challenges to better defining the cognitive phenotype(s) of ASDs. Enhanced knowledge of the cognitive phenotype may contribute to our understanding of the complex links between genes, brain and behaviour, as well as inform approaches to remediation.
2. Fountain C, King MD, Bearman PS. {{Age of diagnosis for autism: individual and community factors across 10 birth cohorts}}. {J Epidemiol Community Health} (Oct 25)
Background The incidence of autism rose dramatically between 1992 and 2001, while the age at which children were first diagnosed declined. During this period the size and composition of the autism caseload has changed, but little is known about whether the factors associated with the timing of diagnosis may also have shifted. Using a multilevel analysis strategy, the individual and community-level factors associated with age of diagnosis were modelled across 10 birth cohorts of California children. Methods Linked birth and administrative records on 17 185 children with diagnoses of autistic disorder born in California between 1992 and 2001 and enrolled with the California Department of Developmental Services (DDS) were analysed. Information on cases, their parents and their residential location were extracted from birth and DDS records. Zip codes of residence were matched to census data to create community-level measures. Multilevel linear models were estimated for each birth cohort, with individual-level effects for sex, race, parental characteristics, poverty status, birth order and symptom expression. At the community level measures of educational and economic composition, local autism prevalence and the presence of a child psychiatrist were included. Results Children with highly educated parents are diagnosed earlier, and this effect has strengthened over time. There is a persistent gap in the age of diagnosis between high and low socioeconomic status (SES) children that has shrunk but not disappeared over time. Conclusion Routine screening for autism in early childhood for all children, particularly those of low SES, is necessary to eliminate disparities in early intervention.
3. Harrington JW. {{The Actual Prevalence of Autism: Are We There Yet?}}. {Pediatrics} (Oct 25)
4. Mack H, Fullana MA, Russell AJ, Mataix-Cols D, Nakatani E, Heyman I. {{Obsessions and compulsions in children with Asperger’s syndrome or high-functioning autism: a case-control study}}. {Aust N Z J Psychiatry} (Oct 25)
Objective: To compare the clinical characteristics and symptom severity of children with obsessive disorder (OCD) plus autism spectrum disorders (ASD) with those of children with OCD plus Tourette’s syndrome (TS) or OCD alone. Method: Children with OCD and ASD (OCD/ASD) (n = 12, mean age = 14.33, range: 12-18) were compared to children with OCD and TS (OCD/TS) (n = 12, mean age = 13.92, range: 9-17) and children with OCD-alone (OCD) (n = 12, mean age = 12.92, range: 9-17) on measures of obsessive-compulsive (OC) symptom frequency, severity, interference and other clinical variables. Results: Patients from the OCD/ASD group rated their OC symptoms as equally distressing, time consuming and contributing to a similar level of interference in functioning as patients in the OCD/TS and OCD groups. The types of symptoms were similar across groups but patients with OCD/TS reported greater frequency of ordering and arranging compulsions, and a trend towards more sexual obsessions. Patients with OCD/ASD reported more peer relationship problems compared with the other two groups. Conclusions: Children with ASD may experience a similar level of impairment from OC symptoms as children with TS plus OCD and children with OCD only. It is suggested that it is useful to establish both diagnoses given that obsessions and compulsions may respond to treatment, and their alleviation may improve functioning in children on the autism spectrum.
5. Maenner MJ, Durkin MS. {{Trends in the Prevalence of Autism on the Basis of Special Education Data}}. {Pediatrics} (Oct 25)
Objective: The goal was to determine whether the increasing prevalence of autism, on the basis of educational data, in Wisconsin between 2002 and 2008 was uniform in all school districts or was greatest in districts with lower baseline (2002) prevalence. Methods: Special education counts were obtained for all Wisconsin elementary school districts from 2002 through 2008. The annual prevalence of children being served under the autism category was calculated for each district, districts were grouped into 8 categories (octiles) according to their baseline prevalence, and prevalence trends were plotted according to octile. Results: The overall prevalence of use of the autism category in Wisconsin elementary schools increased from 4.9 to 9.0 cases per 1000 children between 2002 and 2008. The magnitude of this increase was not uniform across districts and was inversely associated with baseline prevalence. Prevalence in the lowest octile increased from 0.5 cases per 1000 students in 2002 to 7.0 cases per 1000 students in 2008 (P < .0001), whereas no significant trend was seen for the octile with the highest baseline prevalence (range: 11.2-12.3 cases per 1000 students; P = .11). The highest-octile/lowest-octile prevalence ratio decreased from 24.6 (95% confidence interval: 16.2-37.3) in 2002 to 1.8 (95% confidence interval: 1.6-2.1) in 2008. Conclusions: The prevalence of use of the autism special education category in Wisconsin seems to be leveling off in the school districts with the highest prevalence rates, at approximately 12 cases per 1000 students, whereas the gap in prevalence between districts overall has narrowed.
6. Pivac N, Knezevic A, Gornik O, Pucic M, Igl W, Peeters H, Crepel A, Steyaert J, Novokmet M, Redzic I, Nikolac M, Novkovic Hercigonja V, Dodig-Curkovic K, Cacute Urkovic M, Nedic G, Muck-Seler D, Borovecki F, Rudan I, Lauc G. {{Human plasma glycome in attention-deficit hyperactivity disorder and autism spectrum disorders}}. {Mol Cell Proteomics} (Oct 25)
Over a half of all proteins are glycosylated, and their proper glycosylation is essential for normal function. Unfortunately, due to structural complexity of nonlinear branched glycans and the absence of genetic template for their synthesis, the knowledge about glycans is lagging significantly behind the knowledge about proteins or DNA. Using a recently developed quantitative high throughput glycan analysis methods we quantified components of the plasma N-glycome in 99 children with attention-deficit hyperactivity disorder (ADHD), 81 child and 5 adults with autism spectrum disorder (ASD) and total of 340 matching healthy controls. No changes in plasma glycome were found to associate with ASD, but several highly significant associations were observed with ADHD. Further structural analysis of plasma glycans revealed that ADHD is associated with increased antennary fucosylation of biantennary glycans and decreased levels of some complex glycans with three or four antennas. The design of this study prevented any functional conclusions about the observed associations, but specific differences in glycosylation appears to be strongly associated with ADHD what warrants further studies into this direction.
