Exploring the Applicability of Models Explaining Development of Suicidal Thoughts and Behaviours in the General Population to the Case of Autism: A Systematic Review

Background: Recent theoretical frameworks have been developed to explain why those who experience suicidal ideation may or may not go on to attempt suicide in the general population. However, despite growing evidence that suicidality is more prevalent in adults with Autism Spectrum Conditions (ASC) compared to the general population, these theoretical models have not been considered in relation to ASC.

Objectives: This systematic review aimed to identify models conceptualising the movement from suicidal thoughts to suicidal behaviours within the general population and consider their potential application to our understanding of suicide in ASC.

Methods: A systematic search of online databases (Psycinfo, PsycArticles, MEDline, EbscoAcademic Complete, CINAHL and Web of Science) was carried out to identify articles relating to models explaining the movement from suicidal thoughts to behaviours, in the general and ASC populations. In the general population, 385 articles were considered against the search strategy criteria and 7 studies were included in the final qualitative synthesis. The search was repeated to include ASC search terms and no relevant articles were returned.

Results: Three relevant models were identified through the general population search; the Interpersonal-psychological theory, the Integrated Motivational-Volitional model and the Three-Step theory.  Characteristics of ASC were found to overlap with risk factors for both suicidal thoughts and behaviours in the general population. Reported difficulties in ASC including social cognition, and memory biases were represented as factors contributing to suicidal ideation in the general population, particularly within the integrated motivational-volitional model. All three models implicated some ASC symptoms including impulsivity and sensory sensitivities, as conferring increased capability for progressing from suicidal ideation to suicidal behaviours. 

Conclusions: Although the search uncovered no current models of suicidality in people with ASC, findings from general population models generate hypotheses for future research to systematically explore suicidality within ASC populations. The general population models also provide an initial basis for developing ASC specific frameworks which take account of increased risk due to ASC symptomology. Findings of the systematic review and qualitative evidence synthesis provide a useful framework for future research exploring suicidality in ASC.