Residual Social and Communication Deficits In Optimal Outcome Children and Adolescents with a History of Autism Spectrum Disorders

Background: A study is currently following children and adolescents who have a history of autism spectrum disorder (ASD), but who no longer meet diagnostic criteria for the disorder. These individuals have achieved social and language skills within the average range for their ages and receive little or no school support. Several recent studies suggest that this small subset of children, once diagnosed with ASD, achieve an "optimal outcome (OO)" (Sutera et al., 2007, Kelley et al., 2010, and Helt et al., 2008).

Objectives: Despite no longer meeting diagnostic criteria for an ASD, OO individuals may exhibit subtle deficits.  This study examines social and communication functioning in a group of OO individuals.

Methods: The Autism Diagnostic Observation Schedule (ADOS) was conducted with 30 OO individuals (M(age)=13.1), 29 individuals with high-functioning autism (HFA) (M(age)=12.8), and 25 typically developing (TD) peers (M(age)=14.4).  The groups were matched on age, sex and nonverbal IQ; however the groups differed significantly on verbal IQ (M(TD)=111.8, M(OO)=113.2, M(HFA)=103.5, p<.05).  Due to limited variability in this high-functioning sample, ADOS scores for each item were collapsed so that behaviors were coded as either present (0) or absent (1).  The groups were compared on individual items of the ADOS Communication and Social domains, which contain 10 and 11 items respectively, and on a summation of all scores within each domain 

Results: None of the OO individuals met diagnostic criteria for ASD on the ADOS.  T-tests were conducted to determine whether OO individuals differed from TD individuals on the summation score for all items in each ADOS domain.  The groups were not significantly different on the Communication domain (M(OO)=1.70, M(TD)=2.12, p=.35), but were significantly different on the Social domain (M(OO)=2.47, M(TD)=.84, p<.05).  A subsequent t-test comparing the OO individuals to the HFA individuals on the Social domain was also significant (M(OO)=2.47, M(HFA)=9.31, p<.05).  Exploratory chi-square tests were conducted to determine whether OO individuals presented any minor residual deficits as evidenced by the individual ADOS items.  As compared to TD individuals, a significantly greater percentage of OO individuals exhibited restricted range of facial expressions (χ²(1,N=55)=4.10, p<.05), and limited insight into social relationships (χ²(1,N=55)=4.10, p<.05).  There was a marginally higher percentage of individuals in the OO group who had trouble communicating their affect (χ²(1,N=35)=3.58, p=.06), showed a limited number of social overtures (χ²(1,N=55)=3.60, p=.06), and had poorer rapport with the examiner (χ²(1,N=55)=3.44, p=.06).  Follow-up chi-square tests were conducted to compare the OO individuals to HFA individuals on these items.  OO individuals had as much trouble as HFA individuals communicating their own affect.  However, HFA individuals exhibited a higher rate of all the other deficits. 

Conclusions: These results suggest that, relative to TD peers, OO individuals continue to exhibit subtle deficits in specific aspects of social interaction. Additional research with larger samples that includes information about peer relationships will be important to examine this question further. Future research should also examine age effects on these deficits through adolescence, to see if the difficulties abate or worsen with development.