People who have problems with substance misuse often have other mental health challenges. Depression is a commonly co-occurring psychological condition among individuals with substance use problems. Although it has yet to be determined if substance use precedes depressive reoccurrence or depressive symptoms precede substance relapse, it is well known that these co-occurring conditions (COD) are more treatment resistant and result in poorer outcomes than having one condition alone. Research suggests that cognitive behavioral therapy is an effective approach for reducing depressive symptoms. Therefore, Sarah B. Hunter of the RAND Corporation in Santa Monica, California, theorized that addressing depressive symptoms as part of a substance use treatment plan could minimize negative moods, which would reduce the need for negative coping strategies such as substance use.
Hunter and her colleagues administered 16 sessions of group cognitive behavioral therapy for depression (GCBT-D) to 140 individuals being treated at an inpatient facility for substance addiction and compared the outcome to that of 159 individuals receiving usual care. The team assessed the participants at treatment conclusion, 3 months and 6 months posttreatment.
The results revealed significant decreases in substance use, depressive symptoms, and negative outcomes in the GCBT-D group. These results were maintained consistently at both the 3- and 6-month follow-ups. The findings of this study demonstrate that depressive symptoms contribute to substance misuse in this sample. Additionally, Hunter believes that this study clearly shows that efforts aimed at reducing negative affect and depression in substance users can increase abstinence and improve the outcome of treatment in residential settings. Although many of the participants of this study continued to receive therapy at follow-up, the differences in the GCBT-D group and the treatment as usual group at the conclusion of therapy show that it is important for clinicians to address depression in individuals trying to overcome substance addiction. She added that the results suggest the intervention may be effective because it weakens the relationship between depressive symptoms and substance use outcomes.