An Exploratory Analysis of Intolerance of Uncertainty in the Response to CBT Intervention for Anxiety in Children and Adolescents with Autism Spectrum Disorder

Background:  Anxiety is a common co-occurring disorder in children and adolescent with autism spectrum disorder (ASD; White et al., 2009).  Although there is growing evidence that cognitive-behavioral therapy (CBT) may be efficacious in reducing anxiety in some children with ASD (Wood et al., 2014; Storch et al., 2013; Reaven et al., 2012), little is known regarding the mechanisms underlying treatment response.  Intolerance of uncertainty (IU) is a dispositional factor in which individuals experience distress in response to uncertain situations (Buhr and Dugas, 2009).  IU has been identified as a correlate of worry and anxiety in neurotypical youth (Laugesen et al., 2003; Fialko et al., 2012; Comer et al., 2009), and CBT treatments targeting IU have reduced anxiety symptoms in adults and children (Ladouceur et al., 2000; Wilkinson et al. 2011; Leger et al. 2003; Payne et al. 2011).  There is emerging evidence that children with ASD experience increased physiological response to uncertainty (Chamberlain et al., 2013) and that IU mediates the relationship between ASD and anxiety (Boulter et al., 2014).  However, no studies have examined the role of IU in response to CBT interventions in the ASD population.    

Objectives:  This study has two objectives: 1) To examine if pre-intervention IU level predicts response to an established CBT intervention targeting anxiety.  We hypothesize that higher levels of IU will predict lower response to the intervention. 2) To examine if change in IU predicts change in worry and anxiety severity following intervention.  We hypothesize that greater change in IU will result in greater change in worry and anxiety severity.

Methods:  Participants were youth aged 8 to 14 years with ASD, recruited from multiple sites, who completed the Facing Your Fears CBT group therapy program for children and their parents (Reaven et al., 2011) targeting DSM-IV anxiety disorders (GAD, Social Anxiety, SAD).  Diagnosis of ASD was confirmed using the ADOS (Lord et al., 1999).  Anxiety disorder was established using the ADIS-P (Silverman & Albano, 1996).  Approximately 36 children and their parents completed the Intolerance of Uncertainty Scale - Children (Comer et al., 2009) and the Penn State Worry Questionnaire (Pestle et al., 2008), both modified for ASD youth, and the SCARED (Birmaher et al., 1999) preceding and following intervention. 

Results:  Data collection will be completed by December 2014.  Exploratory analysis will include descriptive statistics using t-tests and chi-square tests. Paired t-tests will be used to examine the distribution and change in IU and anxiety across the two time points. We will use robust linear regression models to examine the relationship between change in IU and treatment response, controlling for pre-intervention anxiety levels and to investigate change in anxiety and worry following intervention.  Analyses will also investigate the role of age and ASD severity by controlling for them in the linear regression model.

Conclusions:  This novel study examines the role of IU in treatment response to CBT in youth with ASD.  Results will provide critical direction to enhance the efficacy of psychosocial assessment and treatment of anxiety in individuals with ASD.