Preschool social interaction with children with autism improves parent-child interaction, but does not appear to offer clinically significant improvements in autism symptoms, researchers in the UK reported this week in The Lancet.

The report, written by Professor Jonathan Green, University of Manchaster and team from the *PACT Consortium is being presented at the International Meeting For Autism Research (IMFAR), 9th Annual Meeting, Philadelphia, USA, 20-22 May.

* PACT Consortium: The study, funded by the Medical Research Council, UK, was led by Professor Jonathan Green and colleagues from the University of Manchester and comprised a team of researchers from the Institute of Education, Newcastle University, King’s College and Guy’s Hospital, and the NHS Primary Care Trusts of Stockport, North Tyneside, Southwark and Lewisham.

Autism is a developmental disorder which affects approximately 1% of children in the UK, and results in a yearly UK cost in childhood of £2.7 billion ($4.1 billion) – a higher cost than diabetes or asthma.

Prompt (early) and effective intervention is an international health priority – PACT is important as it is by far the largest autism treatment trial of its type undertaken internationally so far. Results of small trials have suggested that early interventions for social communication may be effective for the treatment of childhood autism. In PACT, the authors aimed to provide a stringent test of a parent-child communication-focused intervention in children diagnosed with autism, aged 2 years to 4 years and 11 months.

The basis behind the PACT intervention was that these children would respond with improved communicative and social development if parents could adapt their communication to their child’s specific impairments.

The intervention involved:

  • 1-to-1 (1-on-1) clinic sessions with therapist and parents and the child. The aim was firstly to increase parental sensitivity and responsiveness to the autistic child’s particular pattern of communication using direct work with parents and video feedback methods.
  • Then, the additional incremental development of the child’s communication was encouraged by introducing a series of strategies such as action routines, matching language to the child’s understanding, and the utilization of pauses.
  • Following a preliminary orientation meeting, families attended 2 hour clinic sessions fortnightly for 6 months, followed by monthly booster sessions for 6 months (maximum 18).
  • Families were also asked to do 30 minutes of daily home practice between sessions.

The study involved 152 children aged between 2 years and 4 years and 11 months, in three locations in the United Kingdom.

  • 77 children received treatment as usual while
  • 75 were assigned to the PACT intervention plus treatment as usual

Treatment as usual consisted of various generic and specialist autism services provided by local health, education and social care services.

Autism symptom severity and improvement was assessed using a modification of the Autism Diagnostic Observation Schedule-Generic [ADOS-G] total social communication score. The researchers report that at the 13-month endpoint, the severity of symptoms was reduced by:

  • By 3•9 points in the group assigned to PACT and treatment as usual
  • 2•9 in the group assigned to just treatment as usual

This represented a small between-group effect size in favour of PACT, after making adjustments for centre, sex, socioeconomic status, age, and verbal and non-verbal abilities – the authors said this was not enough to call a significant clinical effect.

On the other hand, the PACT intervention did lead to improvements in the timing of parents’ communicative interactions with their child, as well as the amount that children communicated using speech and gestures (body language) when playing with their parents. According to parental reports, there were also improvements in their child’s language abilities.

The authors concluded:

On the basis of our findings, we cannot recommend the addition of this PACT intervention to treatment as usual for the purpose of reduction in autism symptoms. The intervention does, however, significantly alter parent-child dyadic social communication in ways that are associated with subsequent positive child outcomes in longitudinal studies, and are likely to be positive for parents themselves. Techniques to aid transmission of these gains in parent-child interaction to children’s communication skills in wider contexts need to be assessed.

The researchers said that their study adds to the positive evidence-base for preschool interventions for children with autism that concentrate on improving children’s social interaction and communication, and that also offer support to parents following a diagnosis.

In line with other recent studies, however, these improvements did not appear to lead to a reduction in the severity of autism symptoms. This difficulty in generalisation is a challenge for health care professionals and researchers in trying to improve interventions for autism.

In an accompanying Comment, Dr Sarah J Spence, and Dr Audrey Thurm, Pediatrics and Behavioral Neuroscience Branch, Intramural Research Program of the National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA, wrote:

This study furthers the field by setting a new bar for the minimum standards of rigorous methodology needed in trials that have potentially far-reaching service and policy implications… At the same time, today’s study exemplifies the complexity of attempting to detect change in samples of young children with such a heterogeneous condition. There are very few positive published trials in autism, for behavioural interventions, traditional pharmacotherapy, or complementary/alternative therapies. Is this due to non-efficacious treatments, lack of sensitive outcome measures, or heterogeneity of autism – or perhaps all three?

They concluded:

In addition to those [variables] examined within this study (eg, variability in diagnoses, baseline language and cognitive levels, socioeconomic status, and parent’s education, age, and sex), there remains a long list of issues that are difficult to even measure and certainly to account for in any sample of individuals with autism. These factors include environmental context, other treatments, co-morbid conditions, and as yet unknown differences in genetics and neuropathophysiology. Ultimately, the challenge is to define subtypes within this disorder. These definitions might have not only important treatment implications, but also aid in understanding aetiology.

“Parent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial”
Prof Jonathan Green FRCPsych, Prof Tony Charman PhD , Prof Helen McConachie PhD, Catherine Aldred PhD, Vicky Slonims PhD, Prof Pat Howlin PhD, Prof Ann Le Couteur FRCPsych, Kathy Leadbitter PhD, Kristelle Hudry PhD, Sarah Byford PhD, Barbara Barrett PhD, Kathryn Temple BSc, Wendy Macdonald PhD, Prof Andrew Pickles PhD, the PACT Consortium
The Lancet, Early Online Publication, 21 May 2010
doi:10.1016/S0140-6736(10)60587-9

“Testing autism interventions: trials and tribulations”
Sarah J Spence, Audrey Thurm
The Lancet, Early Online Publication, 21 May 2010
doi:10.1016/S0140-6736(10)60757-X

Written by Christian Nordqvist