6.35 Behavioral and Neural Mechanisms of Trauma Symptomatology in Youth With Autism Spectrum Disorder

Abstract

Previous research has demonstrated that youth with autism spectrum disorders (ASD) are more likely to experience adverse childhood experiences (ACEs) and may be at greater risk for developing PTSD following such events. Our research aimed to utilize the longitudinal ABCD study to assess the prevalence and underlying mechanisms of increased risk of ACEs, trauma, and PTSD in youth with ASD. Youth with ASD (n = 196) were identified and a typically developing control (CTL) group was established using nearest neighbor propensity score matching on age, sex, MRI scanner, IQ, and socioeconomic status (SES). Using data from the Family Environment Scales, K-SADS, Family History, Short Social Responsiveness Scale, Youth Life Events Scale, and Longitudinal Parent Demographics Survey, we compared the relationship between ACEs and PTSD symptoms between groups using negative binomial regression and moderation analyses of functional connectivity (FC) MRI measures provided by the ABCD consortium seeded in the amygdala. Youth with ASD had significantly more ACEs compared to CTL peers and met DSM-5 criteria for PTSD (per K-SADS-5) at nearly twice the rate (9.9%) of their CTL peers (5.2%, p = 0.020). Poor social skills were associated with more PTSD in CTL compared to ASD and externalizing and internalizing behaviors predicted PTSD above and beyond ACEs differently for the two groups. More positive right amygdala FC with the visual, auditory and sensory-motor hand networks predicted more PTSD symptoms in ASD youth with high ACEs (visual & auditory) or all levels of ACEs (SM hand). This is the first study to examine the prevalence of PTSD in a community sample of youth with ASD who did not come to study attention through clinical interactions and confirmed the higher rate of PTSD in ASD. Alterations in FC in the ASD group suggest underlying ASD-related abnormalities may be risk factors for development of PTSD and that youth with ASD respond differently to ACEs and/or develop different compensatory mechanisms. The differential expression of internalizing and externalizing behaviors associated with PTSD underlines the importance of assessing for ACEs and post-traumatic symptoms in youth with ASD as these youth may have greater difficulty mounting appropriate resiliency responses and therefore need further intervention.