Targeting Obesity Among Cancer Patients with Mindfulness-Oriented Recovery Enhancement: Results from a Randomized Controlled Trial

Background and Purpose:  Obesity is an important public health issue and a recognized risk factor for various comorbid conditions including depression, anxiety, Type 2 diabetes, cardiovascular disease, and cancer.  These negative correlates of obesity are further compounded by weight discrimination, which matches and in some cases exceeds the prevalence of discrimination based on gender and race but remains a socially acceptable and legal form of bias.  In order to address the increased risks associated with obesity for cancer patients, Huntsman Cancer Hospital developed a program that includes dietary counseling and exercise prescription.  Similar programs have achieved successful short-term weight loss, but do not target the underlying causes of obesity, resulting in over 85% of individuals regaining weight lost or even exceeding pretreatment weight.  Neurobiological research indicates that obesity is associated with a blunted ability to experience reward from food and other natural healthy pleasures, resulting in decreased sensitivity of the brain reward system and signs of addiction including tolerance, dependence, and food-attentional bias – a hyperfixation of attention on food-related thoughts and cues.  Mindfulness-based interventions have emerged as empirically supported therapeutic approaches for disorders of appetitive self-regulation by targeting stress- and cue-induced appetitive processes, ameliorating intrusive thoughts and cravings.  Mindfulness-Oriented Recovery Enhancement (MORE), a novel social work intervention, is distinct among mindfulness-based interventions in that it incorporates savoring, which has been shown to target reward-processing deficits and enhance responsiveness to natural rewards.  In this pilot randomized controlled trial (RCT) we assessed the efficacy and feasibility of MORE as an added component to a traditional weight loss program.  We hypothesized that participants in the MORE condition would show greater therapeutic benefits, including decreased attentional bias to food cues, which would be mediated by increased responsiveness to natural reward. 

Methods:

Participants (N=51) were obese female patients recruited through oncologist referrals and randomized to 10 weeks of either MORE and twice weekly exercise groups and nutrition counseling, or the exercise and nutrition components alone.  Licensed clinical social workers led the weekly MORE group.  Measures included a physical health assessment, self-report scales, cognitive tasks, and psychophysiological measurements.  Data were analyzed using mixed effects linear models in order to determine time x treatment interactions on outcome measures, and subsequent path analyses examined the therapeutic mechanisms of treatment effects. 

Results:  A mixed effect linear model revealed a significant time x treatment interaction on food-attentional bias (F = 9.67, p < .01), indicating that MORE significantly decreased attentional bias to food cues. Subsequent path analyses demonstrated that the effect of MORE on reducing food-attentional bias was mediated by increased responsiveness to natural rewards, measured by zygomatic electromyography (EMG).  MORE was significantly associated with increases in reward responsiveness (β = .47, p < .05), which was significantly associated with decreased food-attentional bias (β = -.42, p < .05). 

 

Conclusions and Implications:  Findings indicate that MORE may be reduce addictive tendencies towards food by increasing sensitivity to natural rewards. Savoring may be a key therapeutic technique in ameliorating obesity.