The aim of this study was three-fold: to compare the rates for suicidal behaviors based on the problem substance, to look at the association between addiction severity and suicidal behaviors, and to identify the components of addiction severity associated with suicidal behaviors. Addiction Severity Index databases from three public rehabilitation centers were merged for analyses, yielding 6,551 evaluations. The rates for suicidal behaviors among those who have a problem with both alcohol and a drug are higher than for those who have a problem with any single substance. The effect of addiction severity on suicidal behaviors persists even when other problem areas are taken into account. Thus, clinicians must pay closer attention to persons with both alcohol and drug problem.
Keywords: alcohol addiction; drug addiction; substance use disorder; suicidal behaviors; treatment.