The effect of early life stress on the cognitive phenotype of children with an extra X chromosome (47,XXY/47,XXX).

Studies on gene-environment interactions suggest that some individuals may be more susceptible to life adversities than others due to their genetic profile. This study assesses whether or not children with an extra X chromosome are more vulnerable to the negative impact of early life stress on cognitive functioning than typically-developing children. A total of 50 children with an extra X chromosome and 103 non-clinical controls aged 9 to 18 years participated in the study. Cognitive functioning in domains of language, social cognition and executive functioning were assessed. Early life stress was measured with the Questionnaire of Life Events. High levels of early life stress were found to be associated with compromised executive functioning in the areas of mental flexibility and inhibitory control, irrespective of group membership. In contrast, the children with an extra X chromosome were found to be disproportionally vulnerable to deficits in social cognition on top of executive dysfunction, as compared to typically-developing children. Within the extra X group the number of negative life events is significantly correlated with more problems in inhibition, mental flexibility and social cognition. It is concluded that children with an extra X chromosome are vulnerable to adverse life events, with social cognition being particularly impacted in addition to the negative effects on executive functioning. The findings that developmental outcome is codependent on early environmental factors in genetically vulnerable children also underscores opportunities for training and support to positively influence the course of development.

Cross-sectional evidence for a decrease in cognitive function with age in children with autism spectrum disorders?

Autism spectrum disorders (ASD) are associated with early disturbances in brain maturation processes and these interferences presumably have their consequences for the progressive emergence of cognitive deficits later in life, as expressed in intelligence profiles. In this study, we addressed the impact of age on cognitive functioning of 6- to 15-year-old children and adolescents with ASD. Intelligence profiles were measured by the Wechsler Intelligence Scale for Children and compared among four consecutive age cohorts (children aged 6.17-8.03 years, 8.04-9.61 years, and 9.68-11.50 years and adolescents aged 11.54-15.85 years) of 237 high-functioning boys with ASD. The results clearly demonstrated that the global intelligence level was lower in children aged 8 years and older, when compared with 6- and 7-year-old children with ASD. This is mostly due to the Freedom From Distractibility factor, suggesting that older children were less able to sustain their attention, they were more distractible, or had more graph motor difficulties. Moreover, an effect of age was also found with respect to the relatively poor performance on the subtest Comprehension when compared with other verbal comprehension subtests, indicating that specifically the impairments in verbal comprehension and social reasoning abilities were more profound in older children when compared with 6- and 7-year-old children with ASD. Findings of this cross-sectional study showed that it is relevant to take age into account when evaluating the impact of cognitive impairments on intelligence in children with ASD, because the impact of these developmental disorders might be different at different ages.

Quality of life: a case-controlled long-term follow-up study, comparing young high-functioning adults with autism spectrum disorders with adults with other psychiatric disorders diagnosed in childhood.

BACKGROUND: Long term outcome in childhood autism spectrum disorders (ASD) was evaluated by studying quality of life (QoL) in young adulthood in comparison to the outcome of other child psychiatric disorders. METHODS: In this follow-up study, objective and subjective QoL of 169 high-functioning (IQ>70) adults with ASD (19 to 30 years) was contrasted with QoL data of age matched adults diagnosed with attention deficit/hyperactivity disorder (N=85), disruptive behaviour disorders (N=83), and affective disorders (N=85) during childhood. The mean follow-up period of the ASD patients was 13.9 years. Objective QoL included marital status, living arrangements, level of education, employment, and usage of mental health care. Subjective QoL included satisfaction concerning living arrangements, work or education, physical condition, partner relationship, social relationships, state of mind, and future perspective. RESULTS: QoL was more compromised in adults diagnosed with ASD in childhood than in adults with other psychiatric disorders in childhood. A relatively large proportion of the adults with ASD were single, few lived with a partner or a family and many of them were institutionalized. Adults with ASD had lower educational levels, relatively few had paid employment and many were social security recipients, as compared to the other psychiatric patients. In case the adults with ASD used medication, 47% used anti-psychotics. Regarding the subjective QoL, the adults with ASD were less satisfied about their work or education, partner relationship, and future perspective than the other groups. Even when highly educated adults with ASD were compared to highly educated adults diagnosed with other childhood disorders, the QoL appeared to be more disadvantageous in adults with ASD. CONCLUSION: Many studies have shown that QoL is threatened in psychiatric patients, but findings of this study indicate that young high-functioning adults diagnosed with ASD in childhood are at relatively high risk for poor QoL compared to other childhood psychiatric disorders.

Impaired response inhibition in autism spectrum disorders, a marker of vulnerability to schizophrenia spectrum disorders?

In this study, we addressed the relation between specific deficits in cognitive control and schizotypal symptomatology in adolescents with autism spectrum disorders (ASD) diagnosed in childhood. We aimed to identify cognitive control deficits as markers of vulnerability to the development of schizophrenia spectrum pathology in ASD. Symptoms of autism and the risk for schizotypal symptomatology were assessed in 29 high-functioning adolescents with ASD, and compared with 40 typically developing adolescents. Cognitive control (response inhibition, mental flexibility, visuo-motor control, interference control, and perseveration) was evaluated for specific association with schizotypal symptomatology. Impaired response inhibition appeared to be strongly and specifically associated with schizotypal symptomatology in adolescents with ASD, especially those with positive and disorganized symptoms. Response inhibition problems could indicate vulnerability to the development of schizotypal symptomatology in ASD.

Overlap of autistic and schizotypal traits in adolescents with Autism Spectrum Disorders.

This study addresses the unraveling of the relationship between autism spectrum and schizophrenia spectrum traits in a population of adolescents with Autism Spectrum Disorders (ASD). Recent studies comparing isolated symptoms of both spectrum disorders as well as diagnostic criteria for each (DSM-IV-TR) suggest resemblances in the clinical phenotype. A group of 27 adolescents with ASD (11 to 18 years) and 30 typically developing adolescents, matched for age and gender, participated in this study. Within the ASD group 11 adolescents satisfied DSM-IV-TR criteria for schizotypal personality disorders. Autistic and schizotypal traits were identified by means of well validated questionnaires (Autism Questionnaire, AQ and Schizotypal Personality Questionnaire-Revised, SPQ). Significantly more schizotypal traits in adolescents with ASD were found than in typically developing controls. Besides high levels of negative symptoms, adolescents with ASD also displayed high levels of positive and disorganized symptoms. There appeared to be a relationship between the mean level of autistic symptoms and schizotypal traits, as well as specific associations between autistic symptoms and negative, disorganized and positive schizotypal symptoms within individuals. Schizotypal symptomatology in all sub dimensions that are reflected by the SPQ scores, was most prominently associated with attention switching problems of the autism symptoms from the AQ. These findings indicate that patients diagnosed with an ASD show schizophrenia spectrum traits in adolescence. Although other studies have provided empirical support for this overlap in diagnostic criteria between both spectrum disorders, the present findings add to the literature that behavioral overlap is not limited to negative schizotypal symptoms, but extends to disorganized and positive symptoms as well.