The mediating effects of personality traits on the relationship of youth conduct problems and mood disorders with adulthood suicidality

Identifying the relevant factors for suicidality in individuals with conduct problems is a public health concern, especially if they were under the influence of mood disorders later in life. This study investigates the relationship between youth conduct problems and mood disorders and adulthood suicidality, and to further explore the mediating effects of personality on this relationship. A retrospective cohort study was administered to 308 individuals aged 20–65 years, with or without mood disorders diagnosed by psychiatrists. The Composite International Diagnosis Interview was used to evaluate conduct problems in youth and suicidality (i.e., suicide plan and suicide attempt) in the past year. Personality traits were assessed using Eysenck Personality Questionnaire-Revised for extraversion and neuroticism. Multiple-mediator analysis was used to investigate the mediation effects of personality traits on the relationship between conduct problems and suicidality. The average age of enrolled participants was 31.6 years, and 42.5% of them were female. 39.2% reported suicidality and 43.2% reported conduct problems in youth. Participants who were diagnosed with mood disorders (p < 0.001) and reported having conduct problems (p = 0.004) were associated with high suicidality. Multiple-mediator analysis showed that conduct problems in youth increased the risk of adulthood suicidality through the indirect effects of higher neuroticism (suicide plan: OR = 1.30, BCA 95% CI = 1.04–1.83; suicide attempt: OR = 1.27, BCA 95% CI = 1.05–1.66). Neuroticism mediates the association between youth conduct problems and adulthood suicidality. This finding raises our attention to assess personality traits in individuals with youth conduct problems for designing proper intervention strategies to reduce the risk of suicide.