Social Subtypes In High-Functioning ASD

Background:  

Autism Spectrum Disorders (ASD) are characterized by a high degree of clinical heterogeneity (e.g., Jones & Klin, 2009; Mundy, 2007). This heterogeneity complicates diagnostic assessments and the development of effective interventions. A possibly fruitful approach to this issue is to distinguish subtypes for ASD based on the style of children’s approaches and responses in social interactions: aloof, passive and active-but-odd (cf. Wing & Gould, 1979). Studies show that the active-but-odd group is characterized by higher intelligence when compared to passive or aloof children (e.g., Borden & Ollendick, 1994; Waterhouse et al., 1996), but also by larger deficits in attention and motor control (Bonde, 2000). However, most of these findings are based on samples consisting of low-functioning children and adolescents with ASD (IQ < 70), making generalization to a high-functioning group with ASD difficult (HFASD: IQ > 70).

Objectives:  

Our goal is to explore differences between social subtypes in HFASD regarding symptoms of autism, cognitive skills and comorbid problems.

Methods:  

One-hundred and sixty Dutch children and adolescents diagnosed with HFASD (aged 6 to 18 years) and 53 typically developing controls participated in the study. Additional information on autistic symptoms was obtained with the Autism Diagnostic Observation Scale and the Social Responsiveness Scale. Children completed several competence tasks (e.g., advanced Theory of Mind task) and questionnaires, while parents and teachers completed questionnaires about the child’s behavior. Social subtype of the children was assessed with the Wing Subtypes Questionnaire (WSQ) (Castelloe & Dawson, 1994).

Results:  

Based on the WSQ most children with HFASD were indicated as active-but-odd (41.2%) or without an ASD social subtype (36.6%), followed by passive (19.6%) and aloof (2.6%). Note that HFASD children without an ASD social subtype still had significantly higher (more autistic) SRS-scores than control group children. The Wing subtypes did not differ in age, gender ratio, verbal IQ, clinical diagnosis, or Theory of Mind task performance (p’s >.10). . However, the aloof subtype showed more symptoms of autism (ADOS and SRS) than the other subtypes, while the active-but-odd subtype showed stronger deficits in executive functioning (BRIEF), and higher levels of hyperactivity and problem behaviors at school when compared to the passive subtype (p’s <.05). Data analysis on data collected on the Embedded Figures Test, the Pediatric Quality of Life Inventory and the Interpersonal Reactivity Index is still in progress.

Conclusions:  

This study corroborates the heterogeneity observed in children and adolescents with ASD. Despite non-significant differences between the different social subtypes in age, verbal IQ and clinical diagnosis, aloof children clearly showed most autistic symptoms, while active-but-odd children showed more symptoms of hyperactivity, more behavior problems and more problems with executive functioning. These findings suggest that the social interaction styles as represented by the subtypes may originate from or interact with different problem areas such as deficits in executive functioning or impaired Theory of Mind. Unraveling the dimensions along which children with HFASD differ from each other, such as their social interaction style, may offer entries for enhancement of diagnosis and differential treatment.