Potential Mechanisms Underlying Suicidality in Autistic People with Attention Deficit/Hyperactivity Disorder: Testing Hypotheses from the Interpersonal Theory of Suicide

Abstract

BackgroundAutistic people with co-occurring ADHD appear to be at heightened risk of suicide. To understand why, we explored two explanatory mechanisms from the interpersonal theory of suicide: first, that co-occurring ADHD might be associated with greater risk through greater thwarted belongingness and perceived burdensomeness; and secondly, that hyperactive/impulsive features might incur additional risk through their association with painful and provocative events, which are suggested to create 'capability' for suicide. MethodsAutistic adults (n = 314) completed an online survey including measures of thwarted belongingness, perceived burdensomeness, painful and provocative events, acquired capability for suicide, and ADHD features. Creating an overall index of likely ADHD, we examined associations between likely ADHD, suicide ideation and lifetime suicide attempts via the parallel mediators of thwarted belongingness, perceived burdensomeness, anxiety and depression. In several models, we then examined hyperactive, impulsive and inattentive features as predictors of exposure to painful and provocative events and subsequent capability for suicide, and examined whether these two variables, sequentially or individually, mediated an association with lifetime suicide attempts. ResultsLikely ADHD was associated with past-year suicide ideation via greater depression and perceived burdensomeness, which also mediated its association with more suicide attempts.Hyperactive and impulsive features were associated with exposure to painful and provocative events and through this acquired suicide capability. Both features were associated with more numerous suicide attempts via these two mediators sequentially, and via exposure to painful and provocative events alone. ConclusionsThese data suggest that suicidality in autistic people with ADHD may be partially related to perceived burdensomeness and to acquired suicide capability following exposure to painful and provocative events. However, as we observed a pathway to suicidality associated with painful and provocative events alone, it is likely that there are also other explanatory mechanisms for the influence of traumatic events on suicide risk.

Are autistic females at greater risk of suicide? A call for clarity to advance suicide prevention for the whole community

“…While studies using populationbased records based on ICD codes can miss those who have been misdiagnosed, not yet diagnosed, and/or who have limited access to the healthcare system, online convenience samples (from registries, prior participants, and/or advertised in autistic online spaces) risk overgeneralization from a biased sample (Rubenstein & Furnier, 2021). Specifically, many studies on autistic suicide risk have relied upon online convenience samples (e.g., Cassidy et al, 2018;Conner et al, 2020;Moseley et al, 2023). Although these are a convenient means to acquire large samples and eliminate access barriers (and we have ourselves utilized online samples), it is crucial to note that these studies have often recruited participants that are majority female, high education level, high socioeconomic status, and late diagnosed (Newell et al, 2023).…”