Autism Spectrum Disorder is a neurodevelopmental disorder characterized by two domains of symptoms; social communicative impairments, and fixed interests and repetitive behaviors (FIRBs; APA, 2011). However, ASD often incorporates a wide variety of additional phenotypes making diagnostic accuracy and designing intervention programs difficult (Bellini, 2004). Anxiety symptoms are one of the most frequently reported phenotypes described in children with ASD (Bauminger, 2010, Oswald, Ollendick, & Scahill, 2009). Several studies have measured prevalence of anxiety symptoms among ASD individuals across age groups. The research available on anxiety in this population has demonstrated elevated levels of anxiety compared to other populations of children (Gillott et al., 2001; Kim et al., 2000). One popular suggestion why anxiety is a commonly reported feature in children with ASD is that this population lacks the coping mechanisms needed to manage stress (Groden et al, 2002). Anxiety has been described as an outcome of FIRBS, such that characteristic behaviours like insistence on sameness may lead to anxiety in children with autism (Muris, 1998) or that FIRBS are a way of coping with stress. In either case, increased levels of FIRBS would predict increased levels of anxiety.
Objectives:
The main objective of the current study is to examine the ability of FIRBs at baseline to predict anxiety 12-months later. Additionally, we examined whether the relationship between FIRBs and anxiety is influenced by child variables characteristics such as gender, age, IQ, and other ASD symptoms (i.e., social communication deficits).
Methods:
The sample consists of 68 preschool children who met clinical criteria for ASD according to the DSM-IV. A hierarchical linear regression was conducted to investigate whether FIRBs (as indexed by the Repetitive Behaviour Scale- Revised (RBS-R) overall score mean) at baseline predicts anxiety (as indexed by the Child Behaviour Checklist (CBCL) 1.5-5 anxious/depressed t-score) 12-months later over and above all child variables (age, sex, IQ) and other behaviour measures (ADOS module 1 social and communication raw scores).
Results:
FIRBs at baseline significantly predicted anxiety 12-months later (r2=0.49, p=0.001) over and above all child variables (Age, sex, IQ and other behaviour measures). None of the child variables were significant predictors of anxiety.
Conclusions:
The current study proposes that FIRBs are a predictive measure of later anxiety in preschool children with ASD. This finding provides important clinical implications in terms of a clinical acknowledgement that early FIRBS may be an early manifestation of later anxiety or of treating FIRBs at an early age to prevent the onset of anxiety. Furthermore, these results combined with previous literature inform us that anxiety covaries with FIRBs and provide new information with regards to the way in which anxiety interacts with the core diagnostic features of ASD.
See more of: Clinical Phenotype
See more of: Symptoms, Diagnosis & Phenotype