A Call for the Proper Evaluation of Treatment for Co-Occurring BD and SUD
Considerable research in psychology documents the co-occurrence of addictive behavior and mood disorders. When a person is diagnosed with both a mental illness and co-occurring substance use disorder (SUD), they are considered to have a "dual diagnosis". It is crucial for psychologists to concern themselves with both aspects of this dual diagnosis in order to research and provide effective, comprehensive, and sustainable treatment for clients. Bipolar disorder (BD), in particular, has a very high rate of dual diagnosis. Sasson, Chopra, Harrari, Amitai, and Zohar (2003) report that 60% of individuals diagnosed with bipolar disorder also exhibit symptoms of other disorders, and more than 40% report simultaneous drug use, posing a unique challenge to clinicians and researchers. For these dually diagnosed patients, response to medication is often altered by their drug habit, their symptoms are harder to detect, and they have higher rates of relapse, hospitalization, and suicide attempts (Xie, McHugo & Drake, 2009).There is a crucial need to identify the best treatment option for those who suffer from the combined effects of BD and SUD. Substantive data collected by the National Comorbidity Survey supports such necessity, suggesting psychologists need to increase outreach for patients who are dually diagnosed (Kessler et al., 1996). Although many epidemiological and descriptive studies describe the severity of the issue, very few empirical studies have evaluated possible treatment options. It is difficult to design randomized controlled experiments for this population due to ethical concerns with placing individuals in treatment groups and the breadth of potential confounding factors, such as individual differences in genetic makeup, level of drug use, and self-esteem. In the few empirical studies on aspects of treatment for individuals dually diagnosed with BD and SUD, researchers investigated the effectiveness of three aspects of dually diagnosed patients’ treatment - the way their case is managed, (Drake, Xie, McHugo, & Shumway, 2004), the training of their therapist (Grella & Stein, 2006), and the type of treatment they receive, specifically the effectiveness of medication alone versus medication paired with CBT (Schmitz et al., 2002) - on their treatment outcomes. Even in these few empirical studies that are meant to provide us with greater understanding of how to treat this dual diagnosis, flaws in their very research designs have left the psychological community unable to draw any concrete conclusions. This review hopes to shed light on the methodological flaws of these studies in order to further demonstrate the need for more conclusive research to assess treatment options for this population.
Drake, Xie, McHugo, and Shumway (2004; based on The New Hampshire Dual Diagnosis Study) empirically investigated the longitudinal (1989-1992) treatment outcomes of bipolar outpatients (N=51) based on the way their case was managed. The sample consisted of mostly White (98% White) and male (65% male) patients dually diagnosed with BD and co-occurring SUD. The sample, especially in terms of race, is not representative of the general population and leaves an enormous gap in the lack of generalizability of its findings. In this randomized controlled trial, participants were randomly assigned to receive either assertive community treatment or standard case management (Drake et al., 2004). Though the article noted that both conditions provided integrated services to address dual diagnosis, the authors failed to provide operational descriptions of either condition, making it impossible to account for any resulting significant difference in outcome as a result of management group. Though it failed to find a significant association between outcomes and case management strategy, one value of this study lies in its presentation of the success of treatment for dually diagnosed patients that integrates both aspects of their diagnoses, evident in patients’ improvement in multiple domains (e.g., employment, behavior, functionality) throughout the study.
Grella and Stein (2006) investigated the role of psychologist training and use of on-site dual diagnosis services in patients’ outcomes. Using a sample of 351 patients from 11 residential programs, researchers sought to identify which type of program had the best treatment outcome for dually diagnosed patients. The sample was evenly distributed between males and females (53% male and 47% female) and included a larger proportion of African Americans (35%) than Drake et al.’s (2004) study. It also sought to represent some of the concerns of the African American population - of the 123 African Americans patients who took part in this study, 82% had been homeless and 59% had previously been in trouble with the law. Grella and Stein (2006) found that better training for psychologists and their increased utilization of on-site dual diagnosis services in their treatment improved patients’ outcomes. The study also found higher rates of psychological distress for African Americans, both before and after treatment, as well as a reduced access to healthcare for this population. A major setback of this study is its investigation of co-morbidity in general, rather than BD and SUD specifically (only 65% of the sample suffered from a mood disorder), which means that the results may not acknowledge the unique considerations in the co-morbidity of mood disorders. Though it certainly seeks to present a case for increased dual diagnosis services, this study does not provide clinicians with a concrete idea of what these dual diagnosis services entail and which of their features are really making the difference.
Schmitz et al. (2002) investigated the role of the type of treatment dually diagnosed patients receive on their treatment outcome. In order to test the effectiveness of Cognitive Behavioral Therapy (CBT) in treating co-occurring BD and SUD, 46 patients (80% white, 47.8% male) were randomly assigned to a treatment group with either medication intervention alone or medication intervention with CBT. The medically managed group had 4 clinic visits in three months to monitor their compliance, drug-use, and mood. The CBT group had these clinic visits supplemented with 16 individual sessions of CBT. The results supported the hypothesis that CBT fostered patients’ compliance with medication and improved their mood. However, both groups showed lower rates of substance abuse at the end of the 12 weeks, leading us to believe that CBT did not create any significant difference in addictive behavior between groups. On the other hand, members of the CBT group were found to be more regular in their attendance and showed more satisfaction with their prognosis. How do we make sense of these results? Staying in treatment is linked to more positive treatment outcomes and perception of recovery, as evidenced by patients’ self-reports, so why do these encouraging outcomes not translate into a difference in behavior? Schmitz et al. (2002) acknowledged that the way in which substance use was measured and coded as well as high levels of attrition could have skewed their results. In the face of these methodological concerns, it is difficult to draw any appropriate conclusions from this study.
The review of these articles provides a small sample of the literature that is currently available on treatments for co-occurring BD and SUD. All three studies offer support for the growing consensus that dually diagnosed patients find it much more difficult than patients with a single diagnosis to recover. However, studies often present inconsistent findings and limitations imposed by biased samples, lack of operationalization, and confounding variables. It is apparent that there are not enough soundly designed experimental studies to examine the effects of different aspects of treatment on the co-morbidity of BD and SUD. Therefore, there is an urgent need to properly evaluate new treatment options available to this unique population. Further investigation using experimental techniques needs to help clarify the best aspects of treatment plans for people suffering from co-occurring BD and SUD, rather than lead us further astray.
Drake, R.E., Xie, H., McHugo, G.J., & Shumway, M. (2004). Three-year outcomes of long-term patients with co-occurring bipolar and substance use disorders. Biological Psychiatry, 56(10), 749-756. doi:10.1016/j.biosych.2004.08.020
Grella, C. E., & Stein, J. A. (2006). Impact of program services on treatment outcomes of patients with comorbid mental and substance use disorders. Psychiatric Services, 57(7), 1007-1015. doi:10.1176/appi.ps.57.7.1007
Kessler, R. C., Nelson, C. B., McGonagle, K. A., Edlund, M. J., Frank, R. G., & Leaf, P. J. (1996). The epidemiology of co-occurring addictive and mental disorders: Implications for prevention and service utilization. American Journal of Orthopsychiatry, 66(1), 17-31. Sasson, Y.,
Chopra, M., Harrari, E., Amitai, K., & Zohar, J. (2003). Bipolar comorbidity: From diagnostic dilemmas to therapeutic challenge. International Journal of Neuropsychopharmacology, 6(2), 139-144. doi:10.1017/S1461145703003432
Schmitz, J. M., Averill, P., Sayre, S., McCleary, P., Moeller, F. G., & Swann, A. (2002). Cognitive-behavioral treatment of bipolar disorder and substance abuse: A preliminary randomized study. Addictive Disorders & Their Treatment, 1(1), 17-24. doi:10.1097/00132576-200205000-00004
Xie, H., McHugo, G. J., & Drake, R. E. (2009). Subtypes of clients with serious mental illness and co-occurring disorders: Latent-class trajectory analysis. Psychiatric Services, 60(6), 804-811. doi:10.1176/appi.ps.60.6.804