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. Autistic people are more likely to think about and die by suicide than non-autistic people. Understanding why autistic people experience suicidal thoughts and behaviors could help develop better suicide prevention strategies. We wanted to examine how well an existing model for understanding suicide applies to autistic people. We explored the integrated motivational–volitional (IMV) model of suicide. This model suggests that feeling entrapped in an impossible situation with no escape route and feeling defeated by life increase the risk of experiencing suicidal thoughts in non-autistic people. We wanted to know whether feeling entrapped and defeated are also relevant for autistic people experiencing suicidal thoughts. We also wanted to observe whether the IMV model could be tailored to include experiences that are more relevant to autistic people. Therefore, we also looked at camouflaging, or masking autistic traits to fit in social situations, and intolerance of uncertainty as potential contributors to suicidal thoughts in autistic adults. We recruited 374 autistic adults (aged 18–63 years) to complete online questionnaires measuring the feelings of defeat, entrapment, camouflaging, intolerance of uncertainty, and suicidal thoughts and behaviors. Our results suggest that autistic adults who feel defeated also tend to feel entrapped and suicidal. These results support the IMV model in autistic adults. Autistic adults who reported high levels of camouflaging or intolerance of uncertainty were more likely to score highly on the measure of suicidal thoughts and behaviors. However, camouflaging and intolerance of uncertainty alone were not able to predict suicidal thoughts in autistic adults. Our study is the first to explore this well-supported model of suicide in autistic adults. Our findings provide some insight into some of the reasons underpinning suicidality in autistic adults. This is important as lots of previous research has focused on what the problem is, that is, reporting rates of suicidal thoughts and behaviors. Our study also identifies a number of questions to pursue in future work and shows that it is important for researchers to include experiences that are relevant and important to autistic adults. Data were collected at one time point, and therefore, it is not possible to comment on causal relationships across the information collected. We did not ask participants to confirm their diagnosis or complete an autism screening tool. This was driven by a wish to respect self-identification as well as in response to feedback on completing screening tools. The questionnaires we used were not all developed or tested for use in autistic groups. We did not measure socioeconomic status, which is commonly associated with suicide risk. Understanding why autistic people are at risk of suicide is important for informing clinical approaches to care and support as well as informing suicide prevention strategies. This study expands the current understanding of suicide in autism and provides further avenues for future research to build upon and broaden the evidence base.