6 year follow-up supports early autism intervention
Authors: Jeff Sigafoos, Hannah Waddington
Journal: The Lancet (2016)

There have been few large randomised controlled trials of early intervention for children with autism spectrum disorder, even fewer with follow-up data, and none with such a lengthy follow-up period as that reported by Andrew Pickles and colleagues1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar in The Lancet. These researchers assessed long-term outcomes for children who had received a parent-mediated intervention versus treatment as usual nearly 6 years earlier. That earlier study from 20102Green J Charman T McConachie H et al.the PACT ConsortiumParent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial.Lancet. 2010; 375: 2152-2160Summary Full Text Full Text PDF PubMed Scopus (516) Google Scholar was notable for its rigorous methodology.3Spence SJ Thurm A Testing autism interventions: trials and tribulations.Lancet. 2010; 375: 2124-2125Summary Full Text Full Text PDF PubMed Scopus (17) Google Scholar The present follow-up study is also worthy of note. To appreciate its importance, some background is needed on the 2010 study. That study was a large randomised controlled trial in which young children (aged from 2 years to 4 years and 11 months) were assigned to receive treatment as usual (n=75) or treatment as usual plus the manual-based Pre-School Autism Communication Trial (PACT) programme (n=77). The PACT intervention is grounded in developmental principles and aims to increase parent sensitivity and responsiveness to child communication through various strategies such as improving parent observation, responsiveness, and focused communication. Compared with other early intervention approaches for young children with autism,4Dawson G Rogers S Munson J et al.Randomized controlled trial of an intervention for toddlers with autism: The Early Start Denver Model.Pediatrics. 2010; 125: 17-23Crossref PubMed Scopus (1492) Google Scholar, 5Estes A Munson J Rogers S et al.Long-term outcomes of early intervention in 6-year-old children with autism spectrum disorders.J Am Acad Child Adolesc Psychiatry. 2015; 54: 580-587Summary Full Text Full Text PDF PubMed Scopus (248) Google Scholar, 6Kasari C Gulsrud AC Wong C et al.Randomized controlled caregiver mediated joint engagement intervention for toddlers with autism.J Autism Dev Disord. 2010; 40: 1045-1056Crossref PubMed Scopus (441) Google Scholar the PACT intervention reported in 2010 was a relatively low-intensity programme. Parents received 2 h clinical sessions every 2 weeks for the first 6 months, followed by monthly booster sessions during the final 6 months. Parents were also asked to implement their newly acquired sensitivity and responsivity skills at home for 20–30 min each day. The treatment effect was initially viewed as modest,2Green J Charman T McConachie H et al.the PACT ConsortiumParent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial.Lancet. 2010; 375: 2152-2160Summary Full Text Full Text PDF PubMed Scopus (516) Google Scholar but the updated analysis reported in this follow-up study1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar reveals greater improvements in the intervention group than in the treatment-as-usual group. The improvements seen from the initial PACT trial are consistent with results from other randomised controlled trials of early autism interventions.4Dawson G Rogers S Munson J et al.Randomized controlled trial of an intervention for toddlers with autism: The Early Start Denver Model.Pediatrics. 2010; 125: 17-23Crossref PubMed Scopus (1492) Google Scholar, 5Estes A Munson J Rogers S et al.Long-term outcomes of early intervention in 6-year-old children with autism spectrum disorders.J Am Acad Child Adolesc Psychiatry. 2015; 54: 580-587Summary Full Text Full Text PDF PubMed Scopus (248) Google Scholar, 6Kasari C Gulsrud AC Wong C et al.Randomized controlled caregiver mediated joint engagement intervention for toddlers with autism.J Autism Dev Disord. 2010; 40: 1045-1056Crossref PubMed Scopus (441) Google Scholar The follow-up study1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar sought to establish the long-term durability of these initial treatment gains. Follow-up was done at 5·75 years after the trial endpoint and included nearly 80% of the original sample. The resulting data, which were analysed with repeated measures approaches, showed sustained treatment effects. Specifically, the severity of autism symptoms was significantly lower for children in the intervention group than for children in the treatment-as-usual group. These differences were evident at the trial endpoint and at this 5·75 year follow-up. Secondary analyses showed that changes in social communication and restricted and repetitive behaviour, which are the two core features of autism, contributed to the overall treatment effect. Although this finding is encouraging, comparison of the results of the initial PACT trial with those in this follow-up reveals conflicting conclusions between the two publications. Specifically, whereas there initially appeared to be no value-added effect for the PACT intervention,2Green J Charman T McConachie H et al.the PACT ConsortiumParent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial.Lancet. 2010; 375: 2152-2160Summary Full Text Full Text PDF PubMed Scopus (516) Google Scholar Pickles and colleagues1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar now conclude that the addition of PACT to treatment as usual produces sustained reductions in the severity of autism symptoms. This apparent discrepancy stems from a change in how the severity of autism symptoms was scored. In the 2010 trial, scores were derived from a social communication algorithm from the Autism Diagnostic Observation Schedule-Generic (ADOS-G).7Lord C Risi S Lambrecht L Cook Jr, EH et al.The autism diagnostic observation schedule-generic: a standard measure of social and communication deficits associated with the spectrum of autism.J Autism Dev Disord. 2000; 30: 205-223Crossref PubMed Scopus (5609) Google Scholar However, for the follow-up study, these scores were updated by calculating ADOS Comparative Severity Scores for the full range of autism symptoms.8Gotham K Pickles A Lord C Standardizing ADOS scores for a measure of severity in autism spectrum disorders.J Autism Dev Disord. 2009; 39: 693-705Crossref PubMed Scopus (1084) Google Scholar The updated scoring scheme seems reasonable and the re-analysed data support the more optimistic conclusions of the follow-up study. Indeed, these new follow-up data raise the intriguing possibility that a 12 month, relatively low-intensity intervention has the potential to produce long-term improvements in autism symptoms. Overall, Pickles and colleagues1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar have made a major contribution to autism research by providing new high-quality evidence to support the potential value of adding the PACT intervention to educational services for young children with autism spectrum disorder. Future research of this type could advance science by attempting to isolate the critical treatment components and mechanisms underlying sustained treatment gains. Pickles and colleagues1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar suggest that their positive long-term outcomes stemmed from optimisation of parent–child social communicative interactions, which then become self-sustaining. Another possibility is that early interventions of this type enable neural development and normalise brain activity.9Dawson G Jones EJH Merkle K et al.Early behavioral intervention is associated with normalized brain activity in young children with autism.J Am Acad Child Adolesc Psychiatry. 2012; 51: 1150-1159Summary Full Text Full Text PDF PubMed Scopus (415) Google Scholar Of course these two possible mechanisms are neither mutually exclusive nor exhaustive. Still, the emerging evidence favouring the PACT intervention1Pickles A Le Couteur A Leadbitter K et al.Long-term symptom reduction following a randomised controlled trial of preschool autism treatment.Lancet. 2016; (published online Oct 25.)http://dx.doi.org/10.1016/S0140-6736(16)31229-6Google Scholar, 2Green J Charman T McConachie H et al.the PACT ConsortiumParent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial.Lancet. 2010; 375: 2152-2160Summary Full Text Full Text PDF PubMed Scopus (516) Google Scholar and similar programmes4Dawson G Rogers S Munson J et al.Randomized controlled trial of an intervention for toddlers with autism: The Early Start Denver Model.Pediatrics. 2010; 125: 17-23Crossref PubMed Scopus (1492) Google Scholar, 5Estes A Munson J Rogers S et al.Long-term outcomes of early intervention in 6-year-old children with autism spectrum disorders.J Am Acad Child Adolesc Psychiatry. 2015; 54: 580-587Summary Full Text Full Text PDF PubMed Scopus (248) Google Scholar, 6Kasari C Gulsrud AC Wong C et al.Randomized controlled caregiver mediated joint engagement intervention for toddlers with autism.J Autism Dev Disord. 2010; 40: 1045-1056Crossref PubMed Scopus (441) Google Scholar suggests that some major, yet undetermined, developmental mechanism might be involved. We declare no competing interests. Parent-mediated social communication therapy for young children with autism (PACT): long-term follow-up of a randomised controlled trialThe results are the first to show long-term symptom reduction after a randomised controlled trial of early intervention in autism spectrum disorder. They support the clinical value of the PACT intervention and have implications for developmental theory. Full-Text PDF Open Access