The Effects of Prospectively Following High-Risk Infant Siblings with ASD: Observation Positively Alters Outcome
Objectives: Measure the effects of prospectively following infants later diagnosed with ASD on parent-reported first concerns, clinical presentation, and service utilization.
Methods: Children were selected to form two groups: 1) a prospectively-followed cohort (children who completed a prospective infant sibling study that included 10 visits from birth to 36 months); and 2) a community-referred cohort (children referred to the center for clinical assessment at a single time point). All children in each cohort: 1) received a clinical best-estimate diagnosis of ASD at 24-36 months; 2) had an older sibling already diagnosed with ASD; and 3) had completed measures of child demographics, development, and service use patterns. Cohorts were then matched on sex, race, cognitive ability, maternal age, maternal history of infertility, pregnancy complications, and gestational age (all factors known to impact parent-reported age of first concern), to yield final samples of n=18 prospectively-followed and n=18 community-referred.
Results: Parent-Reported First Concerns: Age of first concern was significantly earlier in the prospectively-followed cohort (11.7 months) than the community-referred cohort (15.5 months), p = .039. Furthermore, domains of first concern were more diverse in the prospectively-followed cohort (Figure 1). Clinical Presentation: The prospectively-followed cohort had lower ADOS severity scores (p = .027), and higher receptive (p = .013) and expressive (p = .011) language abilities relative to the community-referred cohort. Service Utilization: Although there were no differences in age at therapy onset, community-referred children were often enrolled in speech and occupational therapy, whereas prospectively-followed children were more often enrolled in comprehensive early intervention (p = .026). See Table 1b for all between-group comparisons.
Conclusions: Compared to a community-referred cohort, matched on age of diagnosis, sibling status, and other factors known to influence parent-reported first concerns (Table 1a), children enrolled in the longitudinal study had earlier and more diverse parent concerns, a higher enrollment rate into early intervention, and a less severe clinical presentation of autism symptom severity and language ability. These differences were observed despite similarities in nonverbal cognitive levels and parents’ experience with a child on the spectrum. These findings support early developmental surveillance as a framework in which to aid parents in early identification of a broad range of ASD symptoms, and to aid in accessing early intervention services for their children, likely to have profound positive cascading effects on future development.
See more of: Interventions - Non-pharmacologic - Preschool & Infant