Co-occurring mental and substance abuse disorders: a review on the potential predictors and clinical outcomes

This article reviews the literature on co-occurring mental disorders and substance use disorders. The co-occurrence of mental disorders with substance use disorders presents a major challenge to those who provide psychiatric services. Despite the clinical and social burdens caused by this complex problem, research in this area is still insufficient. We found 18 studies showing potential predictors of co-occurring disorders (COD). Poor outcomes have been associated with: (i) COD compared to single disorders and (ii) COD with prior mental disorder compared to COD with prior substance use disorders. Poorer outcomes were reported for substance use disorder patients with comorbid major depressive disorder, and patients with substance use disorder and post-traumatic stress disorder. Furthermore, more negative outcomes were related to COD patients with temporally prior onset of mood disorders. Comorbidity between major depressive disorder or post-traumatic stress disorder and substance use disorder is suggested in the literature as a potential predictor of COD problems.