Autism characteristics and behavioural disturbances in children with Down syndrome in England and Wales

Student thesis: Doctoral ThesisDoctor of Philosophy


Background: Despite initial beliefs that the association was very rare, recent research indicates that a substantial proportion of children with Down syndrome (DS) also meet diagnostic criteria for an autism spectrum disorder (ASD). Often it is the case that behavioural difficulties faced by these children are attributed to their existing diagnosis of DS and many parents experience major difficulties in obtaining an autism diagnostic assessment. In order to best advise families of children with the co-morbidity, a specific behavioural profile needs to be established.
Aims: (i) To ascertain how many children with DS in England and Wales screen positive for ASD (ii) To examine the behavioural phenotype of DS and co-morbid ASD (iii) To determine the impact of raising a child with DS and co-morbid ASD on the family.
Method: A questionnaire survey, conducted through the Down’s Syndrome Association, screened 485 6-15 year old children with DS in England and Wales for autism characteristics and evaluated their emotional and behavioural profiles. From this sample, 50 children with DS (23 with ASD and 27 without) were assessed using adaptive behaviour, autism profile and challenging behaviour outcome measures. Fifty parents were assessed using stress, psychological morbidity and perceived support outcome measures. Thirty-five siblings were assessed using an emotional and behavioural outcome measure.
Results: The proportion of children with DS in England and Wales who screen positive for ASD is substantially higher than in the general population. However, these children show an atypical autism profile when compared with individuals with idiopathic ASD. These children also experience significantly greater behavioural problems than children with DS only and their parents report higher levels of stress than the parents of children with DS only.
Conclusions: Early detection of autism characteristics is important for appropriate intervention. However, the unusual autism profile of this group may affect the recognition of the disorder and hinder the implementation of appropriate interventions. Interventions that focus on challenging behaviours could help reduce difficulties for the children and stress in the parents.
Date of Award2014
Original languageEnglish
Awarding Institution
  • King's College London
SupervisorPatrick Smith (Supervisor)

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