Are Autistic Traits Associated with Suicidality in General Population Young Adults? a Test of the Interpersonal-Psychological Theory of Suicide.

Background: Autism Spectrum Conditions (ASC) have recently been associated with increased risk of suicidality. However, no studies have explored how autistic traits may interact with current models of suicidal behaviour in the general population. This limits our understanding of possible risk and protective factors for suicide among those with ASC, and impedes development of appropriate risk assessments and suicide prevention strategies. The Interpersonal-Psychological Theory of Suicide (IPTS) is potentially a strong candidate for conceptualising the movement from suicidal thoughts to behaviours in relation to autistic traits, given its focus on difficulties which are commonly associated with ASC.

Objectives: To establish how self-reported autistic traits interact with perceived burdensomeness and thwarted belongingness in predicting suicidal behaviour, in the context of the Interpersonal-Psychological Theory of Suicide (IPTS).

Methods: The sample was comprised of 163 general population young adults (aged 18-30 years). Participants completed an online survey including self-report measures of thwarted belonging and perceived burdensomeness (Interpersonal Needs Questionnaire), autistic traits (Autism Spectrum Quotient), current depression (Centre for Epidemiological Studies Depression Scale), and lifetime suicidality (Suicide Behaviour Questionnaire-Revised).

Results: Results showed that burdensomeness and thwarted belonging significantly mediated the relationship between autistic traits and suicidal behaviour. Both depression and autistic traits significantly predicted thwarted belonging and perceived burdensomeness. Autistic traits did not significantly moderate the relationship between suicidal behaviour and thwarted belonging or perceived burdensomeness.

Conclusions: Results suggest that the IPTS provides a useful framework for understanding the influence of autistic traits on suicidal behaviour. Autistic traits present in the general population are associated with increased risk of suicidality. Feelings of not belonging in the world, being a burden on friends and family, and depression are all associated with autistic traits, and account for the association between autistic traits and suicidality. The psychometric properties of these measures need be explored in those with clinically confirmed diagnosis of ASC, in order to replicate and extend these findings. However, clinicians need to be aware of increased risk of suicidality in those with high autistic traits, and when present, screen for suicidal thoughts, behaviours, and feelings of belonging, burden and low mood.