Treatment engagement and response to CBT among Latinos with anxiety disorders in primary care.

Anxiety disorders are prevalent in Latino populations. Findings from epidemiological studies based in the United States (US) suggest that lifetime rates of anxiety disorders among Latinos range from 19–30% (Burnam, Hough, Karno, Escobar, & Telles, 1987; Vega et al., 1998; Vicente et al., 2006). Data also suggest that US born Latinos, particularly those of Mexican origin, are at higher risk than immigrant Latinos, for mood, anxiety, and substance use disorders (Alegria et al., 2008; Grant et al., 2004; Vega et al., 1998). Despite the remarkable presence of anxiety and related disorders, Latinos are less likely than non-Latino Whites to use outpatient mental health services (Miranda & Green, 1999; Ojeda & McGuire, 2006) and are also less likely to receive evidence-based care (U.S. Department of Health and Human Services, 2001). These disparities underscore a treatment need for a large and growing segment of the US population. Cognitive-behavioral therapy (CBT) is the primary evidence-based psychosocial intervention for anxiety disorders (Butler, Chapman, Forman, & Beck, 2006). However, few studies have examined the efficacy of CBT with Latinos (Miranda et al., 2005; U.S. Department of Health and Human Services, 2001). Most randomized controlled trials (RCTs) for adults with anxiety disorders have only recruited small proportions of Latinos, making any kind of ethnic specific analysis impossible. As an example, in a recent review of RCTs for obsessive compulsive disorder, only 1.0% of 2,221 participants from 21 trials were Hispanic/Latino (Williams, Powers, Yun, & Foa, 2009). Studies examining the efficacy of CBT for Latino children and adolescents with anxiety disorders are more common, albeit still few. Findings from these RCTs have found comparable outcomes among Latino and non-Latino White youth on measures of clinical response, remission, symptom severity and overall functioning (Pina, Silverman, Fuentes, Kurtines, & Weems, 2003; Pina, Zerr, Villalta, & Gonzales, 2012; Silverman, Pina, & Viswesvaran, 2008). RCTs that evaluate CBT for Latinos with depression, a distinct but related disorder, are more numerous, particularly in primary care settings (Horrell, 2008; Miranda et al., 2005). Primary care based interventions may be particularly well-suited for Latinos who often experience more barriers to access, and endorse more stigma regarding seeking services from specialty mental health settings (Vega et al., 2007; Vega et al., 1999). Findings from these studies suggest that Latinos with depression, including low-income, and Spanish speaking patients, have comparable responses to CBT as other ethnic groups (Miranda, Azocar, Organista, Dwyer, & Areane, 2003; Munoz et al., 1995). In large scale quality improvement programs, which have included a CBT option, significant short and long term effects have been found for quality of care received by Latinos, African Americans and non-Latino Whites, and significant reductions in depressive symptoms have also been found for Latinos and African Americans (Miranda, Duan et al., 2003; Wells et al., 2005). In smaller, community based studies, favorable responses to CBT have also been found for various Latino ethnic subgroups (Comas-Diaz, 1981; Organista, Munoz, & Gonzalez, 1994; Rossello & Bernal, 1999). While findings offer some support for comparable clinical outcomes among Latino and non-Latino White participants who have received CBT, less attention has been devoted to engagement-related constructs, which typically reflect the extent to which a patient participates in treatment (e.g., treatment uptake, adherence, and attrition). Previous studies have found that lower engagement, as defined by fewer sessions attended, lesser homework adherence, and/or higher rates of attrition, can have negative effects on clinical outcomes (Glenn et al., 2013; O’Brien, Fahmy, & Singh, 2009). Studies which have examined differences in engagement between Latinos and non-Latino Whites have mostly focused on depression; these studies have found higher attrition rates in both pharmacological and psychosocial interventions for Latinos when compared to non-Latino Whites (Arnow et al., 2007; Organista et al., 1994). Additionally, problems with medication compliance, CBT attendance, and completion of CBT homework assignments among Latinos have been reported (Aguilera, Garza, & Munoz, 2010; Ayalon, Arean, & Alvidrez, 2005; Miranda & Cooper, 2004). To our knowledge, no studies have examined engagement outcomes for Latino adults participating in a CBT intervention for anxiety disorders. The current study addresses a gap in the literature on the impact of culture/ethnicity on treatment outcomes for patients with anxiety disorders. In this study, participants were recruited from primary care settings, and received therapist-delivered, computer-assisted CBT for anxiety disorders (“CALM: Tools for Living”) as part of the CALM (Coordinated Anxiety Learning and Management) study (Roy-Byrne et al., 2010; Craske et al., 2011). Clinical outcomes such as symptom reduction and remission as well as engagement-related outcomes including session attendance, treatment completion, homework adherence and acceptance of CBT, were examined. Based on the available literature, we hypothesized that Latinos who received CBT would have similar clinical outcomes as non-Latino Whites at the various assessment points. We also hypothesized that engagement outcomes would be less favorable among Latino compared to non-Latino Whites, however given the limited literature, analyses were somewhat exploratory in this regard.