The synthetic hormone oxytocin helps improve social interaction in children with autism, according to a study published in Molecular Psychiatry
Researchers at the University of Sydney’s brain and mind centre used a double-blind, randomised, clinical crossover trial to assess the efficacy, tolerability and safety of an oxytocin nasal spray in 31 children (aged between three and eight years) with autism.
Lead author Adam Guastella says that after oxytocin treatment “parents reported their child to be more socially responsive at home, and our own blind independent clinician ratings also supported improved social responsiveness in the therapy rooms of the brain and mind centre”.
Autism, a lifelong developmental disorder characterised by impaired social interaction and communication, affects around 1% of the population, and the diagnosed incidence in children is 1 in 68, according to background information in the study. Behavioural interventions can lead to significant improvements in impairments, but they are time consuming and expensive. Although effective drug treatment options are limited, the neuropeptide oxytocin has a role in social cognition and the enhancement of bonding and has shown promising results in adults with autism.
The treatment protocol in the Australian study followed a crossover model, with participants randomly allocated to receive oxytocin (12IU) or placebo nasal spray twice daily for five weeks, at the end of which behavioural assessments were made. Following a four-week washout period, participants were reassessed and switched to the other treatment arm (either oxytocin or placebo), with further assessments at week 14. There were two primary outcome measures: change in the caregiver-rated social responsiveness; and change in caregiver-rated severity of repetitive behaviour.
The researchers found that among children with autism a five-week course of oxytocin significantly improved caregiver-rated social responsiveness. The treatment also scored higher than placebo for experimenter-rated impressions of symptom improvement. However, oxytocin had no effect on caregiver-rated severity of repetitive behaviour. Although recent studies have debated the safety of oxytocin treatment for children, the nasal spray was generally well tolerated, and the most common adverse events were thirst, urination and constipation.
Simon Baron-Cohen, director of the autism research centre at the University of Cambridge, says the research extends findings from a study conducted by his research group that showed administering oxytocin nasal spray leads to benefits for people with autism
. “What’s new here is that whereas our study was in adults, this one tests the effects of this ‘social hormone’ in children,” he says.
The research has a strong biological justification from animal, endocrine, cognitive and genetic research, implicating a role for oxytocin in autism, says Baron-Cohen. “Future research needs to consider safety issues, unwanted side effects, and how the oxytocin spray could be used in conjunction with psychological interventions,” he adds.
Frank Pollick, professor of psychology at the University of Glasgow, says the benefits of oxytocin for social processing have always been compelling “so it’s nice to see this study where evidence for these benefits are shown in a group of children on the autism spectrum”.
 Yatawara CJ, Einfeld SL, Hickie IB et al. The effect of oxytocin nasal spray on social interaction deficits in young children with autism: a randomized clinical crossover trial. Molecular Psychiatry 2015. doi:10.1038/mp.2015.162
 Auyeung B, Lombardo MV, Heinrichs M et al. Oxytocin increases eye contact during real-time, naturalistic social interaction in males with and without autism. Translational Psychiatry 2015. doi:10.1038/tp.2014.146