Behavioral therapies developed specifically for co-occurring disorders remain sparse (
Carroll, 2004), and such therapies that have been designed and tested among comorbid adolescents are particularly rare. Our own group of researchers previously conducted a pilot study involving open label (not double-blind) fluoxetine in combination with CBT/MET therapy in adolescents with comorbid major depressive disorder (MDD) and an alcohol use disorder (AUD). Fluoxetine is a widely prescribed selective serotonin reuptake inhibitor (SSRI), which is a type of antidepressant medication. Fluoxetine has been approved by the Food and Drug Administration (FDA) for treatment of major depressive disorder among adolescents and adults. The results of that pilot study demonstrated efficacy for treatment during the acute phase trial and also at each of the yearly follow-up assessments of the five years follow-up period (
Cornelius et al., 2001;
Cornelius et al., 2004;
Cornelius, Clark, et al., 2005;
Cornelius, Clark, et al, 2007). However, that pilot study did not include a placebo comparison group or a naturalistic comparison group that did not receive verbal therapy, so it was unclear whether the improvements in depressive symptoms and in alcohol-related symptoms noted in that pilot study resulted from the fluoxetine, from the CBT/MET therapy, or from the passage of time.
More recently, our own research group conducted a first double-blind, placebo-controlled acute phase study of fluoxetine in comorbid MDD/ AUD youth (
Cornelius, Bukstein, et al., 2009). The results of that study demonstrated large within-group improvements in both depressive symptoms and in drinking, but no significant differences were noted between the fluoxetine group and the placebo group on any of the outcome variables (
Cornelius, Bukstein, et al., 2009). Thus, no efficacy was noted for fluoxetine for treating either the depressive symptoms or the alcohol-related symptoms of that adolescent comorbid population, despite the prominent clinical improvements noted across the subjects who participated in the treatment study. Since all persons in that study received CBT/MET therapy, it appeared that the prominent clinical improvements that had been noted may have resulted from CBT/MET therapy. A naturalistic (no protocol treatment) comparison group was collected for that study, but no assessments of the participants in that comparison group were made during the acute phase of the study, so no definitive assessment of the acute phase efficacy of the CBT/MET therapy could be made. However, a two-year follow-up evaluation was conducted involving both the subjects involved in the randomized acute phase study who had all received manualized CBT/MET therapy and the naturalistic comparison group, so a preliminary evaluation of the long-term efficacy of CBT/MET among comorbid youth could be made as a secondary data analysis. The current paper is the result of that analysis.
To date, no controlled studies other than our own recently published study have been conducted involving CBT/MET therapy among adolescents with comorbid Major Depressive Disorder/Alcohol Use Disorder. However, one previous controlled study of CBT therapy (in combination with a fluoxetine) trial was conducted by
Riggs and colleagues (2007) among a broad sample of comorbid adolescents. That study by
Riggs et al (2007) did not specifically address adolescents with comorbid major depression and an alcohol use disorder, but instead addressed the more heterogeneous population of adolescents with major depression in combination with any substance use disorder. The authors of that study concluded that fluoxetine and CBT had greater efficacy than did placebo and CBT on one but not both depression measures, and was not associated with greater decline in self-reported substance use. The authors of that article speculated that CBT therapy may have decreased the depressive symptoms of their study sample, but they could not make any conclusions about the efficacy of the CBT therapy, because no comparison sample was available that had not received the CBT therapy.
Cognitive behavioral approaches, such as the CBT used in this study, are based on social learning models (
Carroll, 2005:
Deas, 2008). CBT emphasized a functional analysis of drug use, including the development of an understanding of drug use with respect to its antecedents (triggers) and consequences. CBT emphasized the recognition of high-risk situations and the acquisition of skills to cope with craving cues and other high-risk situations. CBT has been shown to be effective across a wide range of substance use disorders (
Carroll, 1996;
Irwin et al, 1999;
Carroll, 2005), including substance use disorders in the presence of co-occurring mood disorders (
Carroll, 2004) and substance use disorders involving adolescents (
Kaminer et al., 2002;
Deas, 2008).
Motivational enhancement therapy (MET), including the MET used in this study, is a brief intervention used to enhance an individual’s engagement in therapy and motivation to make changes regarding substance use and high-risk behaviors (
Miller et al., 1992;
Miller & Wibourne, 2002;
Carroll, 2004). This form of brief intervention is theoretically appealing for adolescents with substance use disorders because adolescents with those disorders are typically non-treatment-seeking, and need to be motivated to engage in treatment (
Tevyaw & Monti, 2004). Primary tenets of MET include using an empathic nonjudgmental stance, performing reflective listening, avoiding arguments, and supporting self-efficacy for change (
Deas, 2008). MET has been shown to be effective across a wide range of substance use disorders, with particularly strong support among alcohol abusing and dependent populations (
Wilk et al., 1997;
Carroll, 2005;
Carroll et al., 2006). MET has also demonstrated effectiveness for treatment of substance use disorder among persons with comorbid psychiatric disorders (
Swanson, et al, 1999;
Baker et al., 2002), and for treating substance use disorders among adolescents ((
Tevyaw & Monti, 2004).
In this report, we present data involving a two-year follow-up assessment in order to provide a first preliminary assessment of the long-term efficacy of CBT/MET among comorbid MDD/AUD youth. The outcome findings presented in this manuscript are the result of statistical comparisons between subjects who had received CBT/MET therapy versus those who had not received CBT/MET therapy during the acute phase study, but instead had received naturalistic care. Those who had received CBT/MET therapy included all subjects who had participated in the acute phase study, which included those who had received fluoxetine and those who had received placebo. We hypothesized that improvements in depressive symptoms and alcohol-related symptoms noted among the CBT/MET subjects would exceed the improvements noted in the naturalistic comparison group.