Rationale and design of the Response to Behavioral Obesity Treatment (REBOOT) study

Background: For poorly understood reasons, individuals of lower socioeconomic status (SES) lose half as much weight in behavioral weight loss interventions as individuals of higher SES. Potential explanations for this disparity involve environmental constraints on healthy eating and physical activity, decision-making tendencies, and exposure to stress and cognitively demanding tasks. The Response to Behavioral Obesity Treatment (REBOOT) study aims to identify mechanisms that account for SES-related disparities in behavioral weight loss outcomes. Methods: Equal numbers of lower and higher SES adults with obesity are allocated to a six-month standard-of-care weight loss intervention. The primary and secondary clinical outcomes are weight change and three key weight control behaviors (dietary lapses, adherence to dietary self-monitoring, and physical activity) across six months. Ecological momentary assessments (EMA) feature embedded cognitive assessments of working memory, present-biased decision making, and processing speed to capture fluctuations in cognitive performance following exposure to adverse experiences in daily life (e.g., stress, resource scarcity). Neighborhood-level data focused on the food retail environment, walkability, and safety obtained from existing databases and self-report. Planned analyses will test whether the expected socioeconomic disparity in weight change is attributable to differential exposure to adverse experiences in daily life, decision-making tendencies, and their joint impact on adherence to weight control behaviors. Discussion: Support for study hypotheses would represent a significant advance in the conceptualization of disparities in behavioral obesity treatment outcomes and suggest the need to mitigate the adverse impact of certain daily experiences on the cognitive processes that support adherence to weight management behaviors.