Exploring the relationship between ADHD symptoms and suicide risk through the lens of the Integrated Motivational-Volitional Model of suicidal behaviour

Attention Deficit-Hyperactivity Disorder (ADHD) is associated with increased vulnerability to suicide. However, understanding of the psychological factors associated with increased risk is limited. Therefore, we investigated the extent to which psychological factors from the Integrated Motivational–Volitional (IMV) model of suicidal behaviour were associated with suicide risk. 696 adults who were recruited to a study on ADHD, mental health and suicide risk completed validated measures that assessed components of the IMV model, ADHD symptoms and mental health history. 642 (92.2%) participants scored 4 or more on the Adult ADHD Self-Report screener (ASRS; Kessler et al., 2005 ), indicating recent ADHD symptoms. Analyses of IMV model factors were conducted in this subgroup. More than nine out of ten (93%) participants reported lifetime suicidal thoughts (n= 597), and 41.7% (n=268) reported a history of suicide attempts. Multivariable analyses showed higher defeat, internal entrapment and perceived burdensomeness were associated with recent suicidal thoughts, while mental imagery distinguished those with suicide attempt from suicidal thought histories. Perceived burdensomeness moderated the entrapment-to-suicidal thoughts relationship. Exploratory mediation analysis indicated entrapment may mediate the defeat-to-suicidal thoughts relationship. This is the first study to apply the IMV model to understanding the ADHD-suicide risk relationship. Psychological factors from the IMV model warrant investigation longitudinally as potentially targets for suicide prevention in people with ADHD. Study highlights • Study used IMV model to explore suicide risk in people scoring ≥4 on ASRS • Defeat, entrapment, burdensomeness were linked to recent suicidal ideation • Perceived burdensomeness moderated the entrapment–ideation relationship • Mental imagery distinguished suicide ideation from suicide attempt history • Entrapment partially mediated defeat–suicidal ideation relationship