Longitudinal associations between types of childhood trauma and suicidal behavior among substance users: A cohort study

Objectives. We examined the longitudinal associations between different types and severities of childhood trauma and suicide attempts among illicit drug users. Methods. Data came from 2 prospective cohort studies of illicit drug users in Vancouver, Canada, in 2005 to 2010. We used recurrent event proportional means models to estimate adjusted and weighted associations between types and severities of childhood maltreatment and suicide attempts. Results. Of 1634 participants, 411 (25.2%) reported a history of suicidal behavior at baseline. Over 5 years, 80 (4.9%) participants reported 97 suicide attempts, a rate of 2.6 per 100 person-years. Severe to extreme levels of sexual abuse (adjusted hazard ratio [AHR] = 2.5; 95% confidence interval [CI] = 1.4, 4.4), physical abuse (AHR = 2.0; 95% CI = 1.1, 3.8), and emotional abuse (AHR = 3.5; 95% CI = 1.4, 8.7) predicted suicide attempts. Severe forms of physical and emotional neglect were not significantly associated with an increased risk of suicidal behavior. Conclusions. Severe sexual, physical, and emotional childhood abuse confer substantial risk of repeated suicidal behavior in adulthood. Illicit drug users require intensive secondary suicide prevention efforts, particularly among those with a history of childhood trauma.