Objective: This study examines a model of treatment for substance abuse and dependence for patients with substance use disorders and concomitant psychiatric disorders. The model focuses on five interrelated sets of variables (social background, intake functioning. dual diagnosis treatment orientation, patients' change on proximal outcomes, and aftercare participation) that are hypothesized to affect dual diagnosis patients' 1-year posttreatment outcomes.
Method: A total of 981 male dual diagnosis patients completed assessment at intake, discharge and 1-year follow-up. The relative importance of each set of variables as predictors of outcome was estimated by constructing block variables and conducting path analyses.
Results: Dual diagnosis patients had a higher abstinence rate at follow-up (39%) than at intake (2%); they also improved on freedom from psychiatric symptoms (from 60% to 68%) and employment (from 20% to 29%). At follow-up, patients in programs with a stronger dual diagnosis treatment orientation showed a higher rate of freedom from psychiatric symptoms (71%) than did patients in weaker dual diagnosis treatment oriented programs (65%); they also were more likely to be employed (34% vs 25%). More change on proximal outcomes and more aftercare participation were also associated with better 1-year outcomes. Patients with less severe psychiatric disorders improved more and responded better to dual diagnosis oriented treatments than did patients with more severe psychiatric disorders.
Conclusion: Treatment programs for substance use disorders that adhere to principles of dual diagnosis treatment obtain better outcomes for dual diagnosis patients, especially for patients with less severe psychiatric disorders.