Social exclusion partially mediates the association of autistic traits and anxiety in young adults

Adverse childhood experiences (ACE) are well-established risk factors for mental illness, including anxiety. Recent research also indicates that social exclusion can also lead to adverse psychological outcomes. Subclinical autistic traits (AT) have been associated with increased reports of ACE, social exclusion, and heightened anxiety, yet the interplay of these variables remains underexplored. This study examined (a) the degree to which ACE and social exclusion contribute to the association of AT and anxiety, and (b) whether the relationships between ACE and anxiety, and social exclusion and anxiety, are contingent on levels of AT. A total of 691 young adults completed self-report measures of AT, anxiety, ACE, and social exclusion experiences. Bootstrapped moderated mediation analysis using structural equation modelling revealed that social exclusion, but not ACE, significantly mediated the association between AT and anxiety. Additionally, AT did not significantly moderate the relationship between ACE and anxiety, nor between social exclusion and anxiety. Our findings suggest that social exclusion may be a mechanism underlying the co-occurrence of AT and anxiety, but not necessarily a more potent factor in the anxiety of individuals with greater AT. • Greater social exclusion mediated the association between autistic traits (AT) and anxiety. • Social exclusion may drive the mediating role of childhood adversity between AT and anxiety. • The link between social exclusion and anxiety did not significantly differ by AT.