Deconstructing the repetitive behaviour phenotype in autism spectrum disorder through a large population-based analysis

Mirko Uljarević; Matthew N Cooper; Keely Bebbington; Emma J Glasson; Murray T Maybery; Kandice Varcin; Gail A Alvares; John Wray; Susan R Leekam; Andrew J O Whitehouse

doi:10.1111/jcpp.13203

Deconstructing the repetitive behaviour phenotype in autism spectrum disorder through a large population-based analysis

J Child Psychol Psychiatry. 2020 Sep;61(9):1030-1042. doi: 10.1111/jcpp.13203. Epub 2020 Feb 10.

Authors

Affiliations

¹ Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry, and Health Sciences, University of Melbourne, Melbourne, VIC, Australia.
² Department of Psychiatry and Behavioural Sciences, School of Medicine, Stanford Autism Center, Stanford University, Stanford, CA, USA.
³ Telethon Kids Institute, The University of Western Australia, Perth, WA, Australia.
⁴ School of Psychological Science, University of Western Australia, Perth, WA, Australia.
⁵ Child Development Service, WA Department of Health, Perth, WA, Australia.
⁶ Wales Autism Research Centre, School of Psychology, Cardiff University, Cardiff, UK.

PMID: 32037582
DOI: 10.1111/jcpp.13203

Abstract

Objective: Restricted and repetitive pattern of behaviours and interests (RRB) are a cardinal feature of autism spectrum disorder (ASD), but there remains uncertainty about how these diverse behaviours vary according to individual characteristics. This study provided the largest exploration to date of the relationship between Repetitive Motor Behaviours, Rigidity/Insistence on Sameness and Circumscribed Interests with other individual characteristics in newly diagnosed individuals with ASD.

Method: Participants (N = 3,647; 17.7% females; Mage = 6.6 years [SD = 4.7]) were part of the Western Australian (WA) Register for ASD, an independent, prospective collection of demographic and diagnostic data of newly diagnosed cases of ASD in WA. Diagnosticians rated each of the DSM-IV-TR criteria on a 4-point Likert severity scale, and here we focused on the Repetitive Motor Behaviours, Insistence on Sameness and Circumscribed Interests symptoms.

Results: The associations between RRB domains, indexed by Kendall's Tau, were weak, ranging from non-significant for both Circumscribed Interests and Repetitive Motor Behaviours to significant (.20) for Insistence on Sameness and Repetitive Motor Behaviours. Older age at diagnosis was significantly associated with lower Circumscribed Interests and significantly associated with higher Insistence on Sameness and Repetitive Motor Behaviours. Male sex was significantly associated with higher Repetitive Motor Behaviours but not Insistence on Sameness or Circumscribed Interests.

Conclusions: The pattern of associations identified in this study provides suggestive evidence for the distinctiveness of Repetitive Motor Behaviours, Insistence on Sameness and Circumscribed Interests, highlighting the potential utility of RRB domains for stratifying the larger ASD population into smaller, more phenotypically homogeneous subgroups that can help to facilitate efforts to understand diverse ASD aetiology and inform design of future interventions.

Keywords: Repetitive behaviours; autism; social and communication impairments.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Autism Spectrum Disorder / diagnosis
Autism Spectrum Disorder / epidemiology
Autism Spectrum Disorder / psychology*
Child
Diagnostic and Statistical Manual of Mental Disorders
Female
Humans
Male
Phenotype*
Prospective Studies
Western Australia