Mechanistic self-regulation targets in integrated behavior therapy for obese and depressed adults: RAINBOW-ENGAGE study

Obesity and depression are top contributors to the global burden of disease and disability; when comorbid, the burden is exacerbated. Understanding the processes and mechanisms contributing to risk will facilitate the development of targeted and personalized approaches to behavior change. Self-regulation is a core construct in empirically supported behavioral interventions for these disorders and a candidate target mechanism for behavior change. Human neuroscience has identified large-scale brain circuits for key self-regulation targets: emotion regulation, cognitive control, and self-reflection. Using a target-driven, experimental medicine approach, the ENGAGE study leverages an ongoing randomized controlled trial (RAINBOW) of integrated behavior therapy for comorbid obesity and depression in primary care to measure self-regulation targets among trial participants. The study aims are to identify and refine the measures (assays), validate target engagement and malleability, and test target-driven optimization of behavior therapy for comorbid obesity and depression. The chosen assays of emotion, cognitive and self-reflective regulation involve multiple domains (neural, physiological, behavioral, and psychological) and settings (brain imaging lab, virtual reality environments, and smartphone-based passive sensing). The assays are included at baseline, 2, 6, 12 and 24 months. We will examine the relationships between assays within and between domains and settings, and how assays of self-regulation targets predict health behaviors and outcomes through 24 months. ENGAGE will provide a toolkit of validated assays of self-regulation targets important for health behavior change. Findings on how self-regulation mechanisms predict behavior and outcomes will advance the development of targeted and personalized intervention strategies for treating obesity and depression, with implications for other common lifestyle-related comorbidities.