Substance use disorders are highly prevalent among people with schizophrenia. Dually diagnosed patients present with unfavorable course and poor long-term outcomes. Integrated, motivation-based treatment for both disorders in the same setting is considered the treatment of choice. However, integrated treatment programs are not readily available and effect sizes of the programs are modest.

To evaluate an integrated psychosocial treatment program for people with schizophrenia and substance use disorders in the setting of a community psychiatric hospital.

100 in-patients with schizophrenia and substance use disorders were randomized to Integrated Treatment (IT) or Treatment as usual (TAU). The IT group was initially treated in a specialized open ward; upon discharge they were offered treatment in a specialized out-patient program of the hospital. The TAU group was initially treated in another non-specialized open ward; upon discharge they were offered treatment in the non-specialized out-patient unit of the hospital. TAU included pharmacotherapy, medical treatment, supportive psychotherapy and further aids by nursing staff and social workers. IT included all elements of TAU plus manualized group therapy with motivational interviewing, psychoeducation and cognitive-behavioral approaches. Assessments were performed at baseline and after 3, 6 and 12 months.

The IT group had slightly less drop-outs in the follow-up period (non-significant). The IT group was more satisfied with treatment and they developed a higher motivation to reduce substance use. Both groups succeeded in reducing substance use during follow-up, whereas the IT group did slightly better (non-significant).