Hybrid Cognitive Behavioral Therapy Versus Relaxation Training for Co-Occurring Anxiety and Alcohol Disorder: A Randomized Clinical Trial

Individuals with an anxiety disorder are 2–4 times more likely to be dependent on alcohol than are others in the general U.S. community (Grant et al., 2004; Kessler et al., 1997; Regier et al., 1990), and up to half of all individuals being treated for alcohol dependence also have an anxiety disorder (e.g., Kushner, Sher, & Beitman, 1990). The strong correlation between anxiety disorder and alcohol dependence suggests that important etiologic and/or maintaining processes link these conditions. Consistent with this possibility, studies show that clinically elevated anxiety at the outset of alcohol treatment predicts a poor treatment response (Driessen et al., 2001; Kushner et al., 2005). A straightforward hypothesis extrapolated from these data is that effectively treating co-occurring anxiety disorders would improve alcohol use disorder (AUD) treatment outcomes. However, empirical tests of this intuitively appealing clinical hypothesis have been disappointing. For example, Bowen, D’Arcy, Keegan, and Senthilselvan (2000) found that 12 hr of standard cognitive behavioral therapy (CBT) for co-occurring panic disorder, a treatment known to be effective in psychiatric patients, produced no better alcohol outcomes than did AUD treatment without CBT. Similarly, Schade et al. (2004) found that adding CBT for co-occurring phobia (social or agoraphobia) to a standard relapse prevention program improved anxiety but did not improve alcohol outcomes compared with the relapse prevention program alone. Randall, Thomas, and Thevos (2001) found that adding a CBT treatment for social anxiety disorder to a standard AUD treatment program actually resulted in slightly worse alcohol outcomes than the standard alcohol treatment alone. Randall and colleagues (i.e., Book, Thomas, Randall, & Randall, 2008; Thomas, Randall, Book, & Randall, 2008) also reported that treatment of social phobia with paroxetine was successful (relative to placebo) in reducing social anxiety but left the level of hazardous alcohol use in their study sample unchanged after 6 weeks. Although these individual studies have not detected effects for anxiety treatment in terms of alcohol outcomes, a recent meta-analysis did identify a small (d = .22) but significant effect for anxiety treatment relative to control in improving alcohol outcomes when combining the results from all available randomized controlled trials (Hobbs, Kushner, Lee, Reardon, & Maurer, 2011). These modest results suggest that processes beyond simple anxiety reduction should be identified and targeted if the AUD treatment outcomes of patients with co-occurring anxiety disorders are to be improved substantially. Kushner, Abrams, and Borchardt (2000) described a “vicious cycle” model in which interacting biopsychosocial factors can link anxiety symptoms with alcohol use in a positive-feedback system that exacerbates both conditions. This view implies that directly modifying processes linking anxiety symptoms with alcohol use and craving in these cases could add therapeutic value beyond anxiety reduction alone. Consistent with this view, studies show that alcohol outcome expectancies modulate the extent to which anxiety symptoms correlate with alcohol use (e.g., Kushner, Abrams, Thuras, & Hanson, 2000b; Kushner, Sher, Wood, & Wood, 1994), and other studies show that such expectancies can be directly modified with a corresponding effect on level of alcohol use (e.g., Beck, Wright, Newman, & Liese, 1993; Darkes & Goldman, 1998). Additionally, whereas conditioned cues have long been considered important in promoting alcohol use and craving (e.g., Poulos, Hinson, & Siegel, 1981), more recent studies have shown that anxiety and other negative affect can serve as conditioned cues for alcohol craving and relapse and that the strength of these associations can be lessened through extinction training (e.g., Cooney, Litt, Morse, Bauer, & Gaupp, 1997; Litt, Cooney, Kadden, & Gaupp, 1990; Sinha, 2009). On the basis of these ideas, Kushner and colleagues (2006) developed and tested a prototype of a hybrid CBT treatment that integrated standard CBT-based panic disorder treatment techniques (e.g., Barlow, Craske, Cerny, & Klosko, 1989) with parallel content aimed at disrupting psychological processes linking anxiety feelings to alcohol use (e.g., Kushner, Abrams, & Borchardt, 2000). Using a quasi-experimental design, Kushner and colleagues (2006, 2009) demonstrated that standard AUD treatment augmented by the hybrid CBT resulted in better 4-month alcohol outcomes than did the AUD treatment alone. However, several potentially important limitations noted in that work included (a) many interested patients who reported drinking to manage social or generalized anxiety symptoms could not participate in the study because they did not have panic disorder; (b) many patients who did participate in the study also experienced significant social and/or generalized anxiety symptoms that, unlike panic disorder symptoms, were not specifically addressed in the prototype hybrid CBT; and (c) use of a nonrandomized quasi-experimental design with AUD treatment as usual as the control group precluded the drawing of strong conclusions regarding the specific treatment effects of the hybrid CBT. The prototype hybrid CBT tested by Kushner and colleagues (2006, 2009) focused on AUD treatment patients with co-occurring panic disorder. However, the scientific literature on which the vicious cycle model was based (cf. Kushner, Abrams, & Borchardt, 2000) did not specify important differences between various domains of internalizing psychopathology in terms of their association with AUD. Consistent with this, Menary, Kushner, Maurer, and Thuras (2011) showed that the increased risk for AUD associated with drinking to manage anxiety was not restricted to any single anxiety disorder subtype. Similarly, Kushner, Wall, et al. (2012) showed that the variance shared by common anxiety (and depression) disorders relate more strongly to AUD risk than does variance that is unique to a single anxiety disorder. Underlying these scientific findings is the high intercorrelation among various internalizing disorders in those with AUDs (e.g., Andrews, Slade, & Issakidis, 2002; Boyd et al., 1984; T. A. Brown, Campbell, Lehman, Grisham, & Mancill, 2001; Kushner et al., 2005; Kushner, Krueger, Frye, & Peterson, 2008; Magee, Eaton, Wittchen, McGonagle, & Kessler, 1996). On the basis of the empirical and theoretical indications that the core processes linking anxiety and AUD transcend specific anxiety diagnoses, along with the practical implications of highly intercorrelated internalizing disorders (above), we concluded that the panic-centric hybrid CBT prototype of Kushner et al. (2006) could and should be expanded to include patients with other common internalizing disorders. In the present study, individuals undergoing a standard community-based AUD treatment with either panic, social, or generalized anxiety disorder were randomized to also receive either the expanded hybrid CBT or an active comparison control treatment, Progressive Muscle Relaxation Training (PMRT; Bernstein & Borkovec, 1973; Jacobson, 1938). PMRT is a widely disseminated program for managing a broad spectrum of anxiety and stress problems that can be easily administered by nonspecialists (e.g., Conrad & Roth, 2007; Jorm et al., 2004; Manzoni, Pagnini, Castelnuovo, & Molinari, 2008; Siev & Chambless, 2007). Features of PMRT that made it attractive as a comparison to the CBT include (a) credibility as a treatment for anxiety in this population, (b) a transdiagnostic focus that could be reasonably applied to any of the qualifying anxiety disorders, (c) a time frame and intensity level that could easily be made to match those of the hybrid CBT, and (d) a focus on anxiety/stress management without any reference to the association of stress or anxiety to alcohol use. This latter feature, in particular, helps to experimentally isolate treatment elements aimed at anxiety reduction (both the CBT and PMRT programs) from those aimed at decoupling anxiety experiences from alcohol use and craving (the CBT program only). The primary aim of this study was to test whether the hybrid CBT, relative to PMRT, improves 4-month alcohol outcomes in AUD treatment patients with any of several common co-occurring anxiety disorders. A secondary aim of this work was to explore whether anxiety outcomes at the posttreatment assessment mediate or moderate group effects on alcohol outcomes at the 4-month assessment. Note that mediation analyses use anxiety outcomes from the posttreatment assessment (just prior to discharge from the residential AUD program) and alcohol outcomes from the 4-month assessment in order to (a) establish the temporal priority of the putative mediator relative to the outcome and (b) avoid the potential for the confounding of anxiety outcomes with alcohol relapse. (Here, it was presumed that participants could not have relapsed to drinking by the posttreatment assessment because they had not yet been discharged from the closely monitored residential program.) Finally, we evaluated whether differences on clinical variables related to either anxiety (e.g., the particular qualifying anxiety diagnosis) or alcohol (e.g., severity of use prior to treatment) moderated the association between treatment group and alcohol outcomes.