Mindfulness-Oriented Recovery Enhancement Restructures Reward Processing and Promotes Interoceptive Awareness in Overweight Cancer Survivors: Mechanistic Results From a Stage 1 Randomized Controlled Trial

Introduction: The primary aims of this Stage I pilot randomized controlled trial were to establish the feasibility of integrating exercise and nutrition counseling with Mindfulness-Oriented Recovery Enhancement (MORE), a novel intervention that unites training in mindfulness, reappraisal, and savoring skills to target mechanisms underpinning appetitive dysregulation a pathogenic process that contributes to obesity among cancer survivors; to identify potential therapeutic mechanisms of the MORE intervention; and to obtain effect sizes to power a subsequent Stage II trial. Methods: Female overweight and obese cancer survivors (N = 51; mean age = 57.92 ± 10.04; 88% breast cancer history; 96% white) were randomized to one of two 10-week study treatment conditions: (a) exercise and nutrition counseling or (b) exercise and nutrition counseling plus the MORE intervention. Trial feasibility was assessed via recruitment and retention metrics. Measures of therapeutic mechanisms included self-reported interoceptive awareness, maladaptive eating behaviors, and savoring, as well as natural reward responsiveness and food attentional bias, which were evaluated as psychophysiological mechanisms. Results: Feasibility was demonstrated by 82% of participants who initiated MORE receiving a full dose of the intervention. Linear mixed models revealed that the addition of MORE led to significantly greater increases in indices of interoceptive awareness, savoring, and natural reward responsiveness, and, significantly greater decreases in external eating behaviors and food attentional bias—the latter of which was significantly associated with decreases in waist-to-hip ratio. Path analysis demonstrated that the effect of MORE on reducing food attentional bias was mediated by increased zygomatic electromyographic activation during attention to natural rewards. Conclusions and Implications: MORE may target appetitive dysregulatory mechanisms implicated in obesity by promoting interoceptive awareness and restructuring reward responsiveness.