Effectiveness of integrated treatment for people with dual diagnoses

Adults with dual diagnoses of severe mental illness and substance use disorders present a unique challenge to publicly funded mental health and substance abuse treatment systems. Among adults with severe mental illness, substance use disorders are associated with greater psychiatric symptomotology, increased risk of homelessness and involvement with the criminal justice system, and a variety of other problems in living. Integrated treatment programs, that attempt to treat both disorders simultaneously, have shown promise for treating this population. This dissertation presents the results of a multi-site pilot of integrated treatment provided by publicly funded substance abuse treatment programs and community mental health centers in a large Southern state. Hierarchical linear modeling was used to examine differences between integrated treatment and standard community mental health services among 349 dually diagnosed consumers. Outcomes included substance use, retention in treatment, psychiatric symptomotology, community functioning, and stage of substance abuse treatment. In contrast to many prior studies, retention rates were quite high. Nearly 90% of clients were retained in the study for at least six months. However, the integrated and standard treatment groups did not differ significantly in terms of retention. Clients in the integrated treatment group used substances less frequently during the 30 days preceding the follow-up interview compared o those receiving standard treatment (means of 6.75 days and 10.48 days, respectively). Unfortunately, the presence of substantial missing data resulted in inadequate statistical power for testing this effect. Likewise, statistical power was insufficient for detecting differences in psychiatric symptomotolgy as measured by the Brief Psychiatric Rating Scale (BPRS). Although the main treatment effect was not significant, two diagnostic predictors—the presence of a personality disorder and the presence of a psychotic disorder—were modestly associated with greater impairment in community functioning as measured by the Multnomah Community Ability Scale (MCAS). Integrated treatment was moderately superior to standard treatment in terms of clients’ stage of substance abuse treatment as measured by the Substance Abuse Treatment Scale (SATS). Implications for integrated treatment and public mental health and substance abuse treatment are discussed. Treatment comparability, site variability, and analysis strategies are discussed in relation to multi-site evaluations.