Suicidality and Non-Suicidal Self-Injury in Adults with Autism Spectrum Conditions

Background: Recent research has shown significantly increased risk of suicidality in Autism Spectrum Conditions (ASC). However, previous studies have utilised clinical samples, lacked validated measures and failed to explore risk or protective factors. Non-suicidal self-injury, unemployment and psychiatric conditions have all been identified as risk factors for suicide in the general population. People with ASC also describe camouflaging their ASC in order to fit in in social situations, at great potential cost to their mental health. However, no study has yet explored all these factors in relation to suicidality in ASC. This is crucial to inform new suicide prevention strategies for this group.

Objectives: 1) To compare the prevalence of suicidality and NSSI between those with and without ASC; and 2) To explore risk and protective factors for suicidality in those with ASC.

Methods: A comprehensive online survey was co-designed with the help of a steering group of adults with ASC who had experienced mental health problems and/or suicidality. Adult males and females with ASC, and control females without ASC or suspected ASC, completed the survey online. Measures included the Suicide Behaviour Questionnaire-Revised (SBQ-R), the Non-Suicidal Self-Injury Assessment Tool (NSSI-AT), and the Autism Spectrum Quotient (AQ). Participants also provided details of diagnosed developmental and mental health conditions, experiences of attempting to camouflage their ASC in order to fit in in social situations, employment, education, treatment and support.

Results: The ASC group comprised 168 adults (67 male, 101 female), and 108 control females without ASC or suspected ASC, aged 20-60 years old, recruited from online adverts and the University of Cambridge Autism Research Database. Significantly more ASC females reported lifetime experience of NSSI (81.8%) than ASC males (55.4%), and control females without ASC (27.6%) (all p < .001). In the ASC group, mean SBQ-R (10.31 SD 4.2) was significantly higher than the recommended cut off for psychiatric populations (>=8); 69.8% of the ASC group scored at or above this cut off. After statistically controlling for age, education, occupational status, living arrangements, co-morbid developmental and mental health conditions, ASC females scored significantly higher on the SBQ-R than control females (10.61 (SD 4.16) vs 6.27 (SD 3.18)). In the ASC group, history of NSSI, at least one mental health condition, unemployment, and camouflaging ASC were associated with significantly higher scores on the SBQ-R (all p < 0.05).

Conclusions: Results showed that a majority of ASC adults had experienced NSSI, and scored significantly above the recommended cut off for suicide risk in psychiatric populations. After controlling for a number of factors such as mental health conditions, unemployment and living situation, ASC females scored significantly higher in suicidality than control females. Results suggest that the factors underlying increased risk of suicidality in ASC compared to the general population goes beyond co-morbid psychiatric conditions and demographic risk factors. One new autism-specific risk factor for suicidality identified was the tendency to camouflage their ASC in an attempt to cope in social situations. Implications for suicide prevention are discussed.