Why Are Autistic People More Likely to Experience Suicidal Thoughts? Applying the Integrated Motivational-Volitional Model with Autistic Adults.

Background: Autistic people are at considerably greater risk of suicidality than non-autistic people, and the reasons behind this are not fully understood. Current suicide theories may be useful to help further our understanding of the mechanisms behind autistic suicidality. We aimed to test the key predictors of suicidal ideation-defeat and entrapment-as described in the integrated motivational-volitional (IMV) model of suicide behavior, in an autistic group. We also looked to extend the IMV model by including autism-related constructs of camouflaging and intolerance of uncertainty (IU).

Methods: We recruited 374 autistic adults from the community (female 42.5%; 18-63 years of age), who completed a cross-sectional online survey between August 2020 and January 2021. We collected data on lifetime suicidality, depression symptoms, defeat, entrapment, camouflaging, and IU.

Results: We found that entrapment significantly mediated the relationship between defeat and suicidal ideation. Camouflaging and IU were not found to moderate this pathway but were found to be significantly associated with suicidal ideation.

Conclusions: We found that entrapment mediates the relationship between defeat and suicidality in autistic adults. This is consistent with the predictions in the motivational phase of the IMV model of suicidal behavior, suggesting that this model is useful for understanding autistic suicidality. We did not find evidence that camouflaging and IU act as moderators within the mediated model. Nevertheless, there is some evidence that camouflaging and IU are worthwhile constructs to be aware of for future work researching autistic suicidality.