The impulsivity-aggressiveness-hostility triad mediates the relationship between stressful life events and completed suicide

Abstract

Background and Objectives: The Interpersonal Theory of Suicide outlines a range of dynamic factors that heighten an individual's susceptibility to displaying suicidal tendencies. Among these factors lies the acquired capacity for suicidal behaviours, which denotes a person's desensitization to pain (both physical and psychological), and fearless to death, cultivated through exposure to adverse life circumstances. Stressful life events (SLE), in conjunction with certain personal traits, notably contribute to this capacity for suicidal behaviour. Traits such as impulsivity, aggression, and hostility are linked to a heightened likelihood of engaging in risky behaviours over one's lifetime, thereby fostering an increased propensity for suicidal acts. The objective of this study, is to introduce the concept of an "I-A-H triad” (“Activating triad”) comprising impulsiveness, aggressiveness, and hostility, as a pivotal intermediary between SLE and suicidal tendencies. Method: Data were gathered from 399 deceased individuals (274 suicides, 125 non-suicides) through psychological autopsy methods. Adapted versions of the Paul Ramsey Life Experience Scale, Barrat Impulsivity Scale (BIS-11), and Buss-Durkee Hostility Inventory (BDHI) were employed to collect information. Findings: Results from comparative analyses between the two groups revealed significant distinctions in key variables of interest (SLE: t = 7.280; BDHI: t = 4.201; BIS-11: t = 3.812; I-A-H Triad: t = 4.84). Mediation analysis affirmed the mediating function of the "I-A-H Triad" in connecting SLE with suicide. Discussion: In conclusion, elevated levels of impulsivity, aggression, and hostility amplify the risk of suicide, particularly in the presence of stressful life events.