Correlates of Middle Adult Outcome: A Follow-up Study of Children Diagnosed with ASD from 1970-1999

Background: While there is a developing literature on Autism Spectrum Disorder (ASD) in adulthood, few longitudinal studies from childhood to adulthood have been conducted. The majority of these studies have focused on the transition years from adolescence to young adulthood or focused on describing adult outcomes. Thus, there is little research on autism in middle adulthood or predictors of positive outcome in this age group.

Objectives: This research capitalizes on a unique dataset of individuals diagnosed with ASD as children by the TEACCH Autism Program from 1970-1999. A caregiver survey was conducted to: (1) Document outcomes (employment, social connectedness, mental health, quality of life) in middle adulthood; (2) Examine current predictors of adult outcome; (3) Examine childhood predictors of adult outcome.

Methods: Thus far, surveys have been completed for 81 adults with ASD in middle adulthood (21-64 years of age, Mean = 34 years) diagnosed during childhood (initial diagnoses from 21 months to 17 years, Mean = 6.5 years). Adult outcome was measured by employment status (Taylor & Seltzer Vocational Index), quality of life (Schalock & Keith Quality of Life Questionnaire), social isolation (NLTS-2 items), and mental health (Anxiety Depression and Mood Scale).  Current predictors included autism symptom severity (Social Responsiveness Scale, SRS-2), adaptive behavior (Waisman Activities of Daily Living), and language ability (NLTS-2 items). Childhood predictors included symptom severity (Childhood Autism Rating Scale), adaptive behavior (Vineland), and IQ.

Results: Seventy-eight percent of adults with ASD had moderate to severe autism on the SRS-2. Despite significant ASD symptoms, a range of developmental level is represented (e.g., little to no difficulty with conversations were reported for 42% of adults). With regards to adult outcome, caregivers reported that only 43% of adults with ASD were employed and 36% were described as being social isolated (no contact with peers in the past 12 months). Regression analyses were conducted to examine predictors of adult outcome. Current adaptive behavior was the single best correlate of adult outcome. Controlling for both current symptom severity and language skills, adaptive behavior was significantly related to employment (partial r=+.55), social isolation (pr=-.30), depression (pr=-.26), and quality of life (pr=+.36). When controlling for adaptive behavior, symptom severity and language ability had little to no impact on adult outcome. Similar analyses were conducted for childhood predictors.  Adaptive behavior in childhood controlling for childhood IQ and symptom severity was an equally strong predictor of employment (pr=+.38), social isolation (pr=-.29), depression (pr=-.28), and quality of life (pr=+.38). The contributions of current and childhood adaptive behavior were largely independent; each significantly predicted outcome when the other was used as a covariate.

Conclusions: Both childhood and adult adaptive behavior were strong, independent predictors of a wide variety of adult outcomes.  The contribution of adaptive behavior went beyond that of either symptom severity or intellectual/language functioning. Interventions targeting adaptive behavior skills are often overlooked; however, these findings emphasize the importance of improving adaptive behavior across the lifespan regardless of symptom severity and communication skills.