Therapeutic intervention for autism spectrum disorder (ASD) is usually started after diagnosis, typically when a child is around three years old. In a randomized trial, researchers investigated whether a preemptive intervention in infants showing early signs of ASD would reduce the severity of symptoms and the likelihood of a diagnosis at age three.

Families were referred by community clinicians and invited to participate if their infant was between nine and 15 months old and displayed at least three of the five behaviors on a standardized checklist indicating a high likelihood of ASD. The intervention uses video feedback techniques to improve caregiver awareness of the infant's social communication and guides caregiver responses to build infant social engagement and interaction.

A total of 104 families were randomized to receive either the intervention plus usual care or usual care only. Adherence to the intervention was high, the researchers note, and no adverse effects were identified. The intervention group had a significant reduction in ASD symptom severity and lower odds of meeting ASD diagnostic criteria at three years of age. Improvements were also seen in caregiver responsiveness and language outcomes in the intervention group.

Pointing to the study's limitations, the authors note that diagnostic judgments were made when the children were three years of age, but diagnostic categories may change for a small proportion of children if they're subsequently reassessed. Follow-up of these children will be important in determining the longer-term clinical significance of the intervention effects observed in this study, the researchers say.

Whitehouse AJO, et al JAMA Pediatr 2021;175(11):e213298.