Adverse childhood events as risk factors for substance dependence: Partial mediation by mood and anxiety disorders

Aims: Adverse childhood events (ACEs) are associated with negative health outcomes. We examined ACEs as risk factors for substance dependence (SD) and the mediating effects of mood and anxiety disorders on the relations between ACEs and SD risk. Design: We compared early life experiences in 2061 individuals with a lifetime diagnosis of alcohol, cocaine, or opioid dependence and 449 controls. Measurements: Diagnostic and ACE data were obtained using the Semi-Structured Assessment for Drug Dependence and Alcoholism. Findings: Childhood abuse or exposure to violent crime was positively related to the number of lifetime mood and anxiety disorders and to SD risk. Mood and anxiety disorders had their first onset a mean of nearly 3 years before the first SD diagnosis and partially mediated the effect of ACEs on SD risk. Conclusion: ACEs appear to contribute additively to the risk of SD, with mood and anxiety disorders in the causal path for a portion of this risk. The identification and effective treatment of mood and anxiety disorders associated with ACEs could reduce the risk of developing SD. (C) 2009 Elsevier Ltd. All rights reserved.