Cognitive-Behavioral Therapy, Behavioral Weight Loss, and Sequential Treatment for Obese Patients with Binge Eating Disorder: A Randomized Controlled Trial

Binge-eating disorder (BED), a research category in the DSM-IV (American Psychiatric Association, 1994), is characterized by recurrent binge-eating accompanied by feelings of loss of control and marked distress in the absence of inappropriate weight compensatory behaviors. BED is a prevalent major health problem (Hudson, Hiripi, Pope, & Kessler, 2007). BED has diagnostic validity (Wonderlich, Gordon, Mitchell, Crosby, & Engel, 2009), differs from other eating disorders and obesity (Grilo et al., 2009; Grilo, Hrabosby, White, Allison, Stunkard, & Masheb, 2008), and is strongly associated with obesity and elevated risk for medical/psychiatric co-morbidity (Hudson et al., 2007; Wonderlich et al., 2009). The treatment literature for BED suggests that several medications have short-term efficacy relative to placebo (Reas & Grilo, 2008) and certain psychological treatments are effective (Wilson, Grilo, & Vitousek 2007). Cognitive-behavioral therapy (CBT) is the best-established treatment (NICE, 2004; Wilson, Wilfley, Agras, & Bryson, 2010). The National Institute of Clinical Excellence (2004) recommendation that CBT is the treatment-of-choice was assigned a “grade-of-A,” reflecting strong empirical evidence. Controlled trials have provided further support for the efficacy of CBT, including “treatment specificity” (Grilo, Masheb, & Wilson, 2005); however, studies have reported little difference between interpersonal psychotherapy (IPT) and CBT delivered via group (Wilfley et al., 2002) or CBT guided-self-help (Wilson et al., 2010). Although CBT generally produces remission rates of 40% to 60% and robust improvements in eating disorder psychopathology it fails to produce weight loss (Wilson et al., 2007). The association between BED and obesity (Hudson et al., 2007) and the possible heightened risk for developing future metabolic problems (Hudson et al., 2010) highlight the need to find methods to effectively reduce weight - in addition to eliminating binge-eating - in persons with BED. The existing literature of behavioral-weight-loss (BWL) for BED is equivocal and difficult to interpret in light of significant methodological shortcomings, particularly the reliance on self-report questionnaires for the assessment of binge-eating, inclusion of heterogeneous patients with varying sub-threshold levels of BED, and a lack of follow-up data (see Wilson et al., 2007; Wonderlich et al., 2009). Overall, CBT appears more effective for reducing binge-eating and associated psychopathology whereas BWL appears more effective for producing short-term weight loss (e.g., Agras et al.,1994; Wilson et al., 2010) although BWL studies in BED (e.g., Devlin et al., 2005; Grilo & Masheb, 2005) and “binge-eaters” (Goodrick, Poston, Kimball, Reeves, & Foreyt, 1998) often report minimal or no weight losses. Interestingly, the modest short-term weight-loss reported by most studies testing BWL for obese BED patients (see Wilson et al., 2007) is at odds with the greater magnitude of weight-losses reported for obese patients who do not binge-eat receiving BWL recruited for obesity trials (e.g., Foster et al., 2003) and with findings from one obesity treatment study in which a post-hoc re-analysis of outcomes for “binge-eaters” (determined by self-report) revealed superior short-term weight-losses relative to non-binge-eaters (Gladis, Wadden, Vogt, Foster, Kuehnel, & Bartlett, 1998). The current study, a randomized controlled trial to test the relative efficacy of CBT and BWL for BED and the durability of the outcomes over a 12-month follow-up period, was designed as a test of treatment-specificity and to help answer the clinically important question of whether BWL has efficacy for weight loss in this subgroup of obese patients. This study also tested the utility of a sequential treatment approach in which CBT is delivered first followed by BWL. Given findings from RCTs that binge remission was associated with greater weight losses (Devlin et al., 2005; Grilo et al., 2005; Wilfley et al., 2002), the comparison to the sequential CBT+BWL treatment follows the clinical hypothesis that once CBT reduces binge eating and associated psychopathology, patients will be able achieve greater weight loss with BWL.