Are autistic traits associated with suicidality? A test of the interpersonal-psychological theory of suicide in a non-clinical young adults sample?

Autism spectrum conditions (ASC) have been associated with increased risk of suicidality. However, no studies have explored how autistic traits may interact with current models of suicidal behaviour in a non-clinical population. The current study therefore explored how self-reported autistic traits interact with perceived burdensomeness and thwarted belonging in predicting suicidal behaviour, in the context of the Interpersonal-Psychological Theory of Suicide (IPTS). 163 young adults (aged 18-30 years) completed an online survey including measures of thwarted belonging and perceived burdensomeness (Interpersonal Needs Questionnaire), self-reported autistic traits (Autism Quotient), current depression (Centre for Epidemiological Studies Depression Scale), and lifetime suicidality (Suicidal Behaviours Questionnaire - Revised). Results showed that burdensomeness and thwarted belonging significantly mediated the relationship between autistic traits and suicidal behaviour. Autistic traits did not significantly moderate the relationship between suicidal behaviour and thwarted belonging or perceived burdensomeness. Results suggest that the IPTS provides a useful framework for understanding the influence of autistic traits on suicidal behaviour. However, the psychometric properties of these measures need to be explored in those with clinically confirmed diagnosis of ASC.