(PS4-71) Self-reported Separation Anxiety and Uncertainty Are Associated with Parent-reported Restricted and Repetitive Behaviors in Autistic Youth

Anxiety is one of the most common co-occurring conditions in autism. Given its prevalence, more research is needed on the behavioral manifestation of anxiety in this population. It has been established that there is a relationship between anxiety and restricted and repetitive behaviors (RRBs), with specific associations between intolerance of uncertainty and RRBs in autistic adults. In youth samples, studies have used parent-report measures of anxiety but have yet to combine parent- and self-report measures, despite that self-report has been demonstrated to be essential for a full understanding of symptoms of anxiety, sensory sensitivities, and RRBs in autism. This study aims to expand on previous findings and address these gaps by comparing parent- and self-report measures to examine the relationship between different types of anxiety and RRBs in autistic teens.

Participants included 179 autistic individuals (35% females assigned at birth) 14-18 years old (M= 16.1, SD= 1.19), with a mean FSIQ of 103 ranging from 66 to 141. Teens completed the Anxiety Scale for Children – ASD (ASC-ASD) containing the following subscales: Performance Anxiety (PA), Anxious Arousal (AA), Separation Anxiety (SA), and Uncertainty (U). Parents completed the Parent-Rated Anxiety Scale (PRAS-ASD) and the Social Responsiveness Scale – 2^nd Edition (SRS-2), including the Restricted and Repetitive Behaviors Index (RRBI). Bivariate Pearson correlations first examined the relationship between PRAS-ASD Total Score and RRBI. Then correlations between self-reported anxiety from each of the different subscale scores and RRBs were examined. Stepwise regressions examined how the different subscales of youth anxiety predict RRBs beyond age, sex, and gender. Two regression models were used for this analysis to account for collinearity and the effects that gender versus sex may have on anxiety and RRBs in this sample.

Correlational analyses indicated that parent-rated anxiety was significantly related to parent-reported RRBs (r = .556, p = < .001). In addition, self-reported total anxiety (r = .254, p =< .001) and specifically, both SA (r = .226, p = .002), and U (r = .278, p = < .001) were significantly related to parent reported RRBI scores. The overall regression models were statistically significant for both SA (R² = 0.059, F-statistic = 6.583, p = .001) and U (R² = 0.084, F-statistic = 9.167, p = < .001), and indicated that SA (β = 0.9792, p .002) and U (β = 0.6937, p = < .001) both predicted RRBs after accounting for age, sex, or gender.

This study emphasizes the association between anxiety and RRBs in autism, specifically SA and U. Consistent significance across self- and parent-reports strengthens the credibility of these findings and highlights the value of cross-informant perspectives, as self-report measures capture unique insights into children’s thoughts and feelings. Future studies should explore this relationship bidirectionally, examining anxiety as both a predictor and outcome of RRBs. Additionally, leveraging longitudinal data is essential to explore RRBs as potential manifestations of anxiety. Such investigations can offer additional support for using anxiety treatments to understand and identify internal experiences related to RRBs in autism.