Overlap of clusters of psychiatric symptoms among clients of a comprehensive addiction treatment service.

This article describes the prevalence and overlap of psychiatric symptoms among 2,784 clients of the outpatient programs at a comprehensive addictions treatment facility. The psychiatric symptoms were assessed by a computer-based questionnaire, and the analysis focused on the overlap of symptom clusters (multimorbidity) and their relation to selected intake variables known to be predictors of treatment outcome. Of all clients, 27.4% scored positive for 1, 18.9% for 2, and 22.3% for 3 or more clusters, the most frequent being depression, anxiety, and history of conduct disorder. Multimorbidity was significantly correlated with female gender, unemployment, less social support, cannabis problems, fewer legal problems, and increased treatment engagement. Clients with more substance use disorders presented more psychiatric symptoms.