Longitudinal Predictors of Adaptive Functioning in Emerging Adults with and without Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) display heterogeneity in adaptive functioning, underscoring the need to identify predictors to inform clinical and scientific interventions. We investigated the longitudinal associations between an autism diagnosis, co-occurring psychopathology symptoms, executive functions (EF) and subsequent adaptive functioning in individuals with and without ASD (IQ > 70). Sixty-six individuals (26 with ASD, 40 without ASD) were assessed at baseline (mean age = 11.8 years, SD = 2.1) and at 10-year follow-up (mean age 21.4, SD = 2.3). The diagnostic evaluation comprised a comprehensive assessment of autism symptoms and emotional and cognitive functioning. Co-occurring psychopathology symptoms were assessed with two measures: self-reported depressive symptoms with the Short Mood and Feelings Questionnaire and parent-reported total problems with the Child Behavior Checklist 6-18. Participants completed neuropsychological tests to evaluate EF. We investigated adaptive functioning by using the Weiss Functional Impairment Rating Scale (WFIRS) which is a self-report measure of impairment in the following domains: family, work, school, life skills, self-concept, social and risk-taking. Among the emerging adults previously diagnosed with ASD, 46% reported living independently, 75% had at least one friend, and 71% were employed or in education. Individuals with ASD reported significantly lower adaptive functioning compared to individuals without ASD (WFIRS Total, Hedges' g = 0.92). Greater EF difficulties in childhood/adolescence predicted lower adaptive functioning in emerging adulthood, surpassing the influence of autism diagnosis and co-occurring symptoms. The findings highlight the influential role of EF, implying that interventions targeting EF difficulties could improve long-term outcomes for individuals with ASD.