Mindfulness and Binge Eating from a Transdiagnostic Framework: Findings from a Randomised Control Trial

Abstract

Abstract: Bulimia Nervosa and Binge Eating Disorder are chronic disorders which significantly impact on the quality of life of individuals who suffer from them. There remains considerable diagnostic, etiological and treatment uncertainty regarding them and the ED-NOS category, which is thought to be the most common clinical presentation. This thesis has introduced a Transdiagnostic Process Model of Binge Eating which has provided a parsimonious explanation for the development and maintenance of BN, BED and ED-NOS. This thesis has identified the need for more effective group treatments for BN and BED, as current group treatments have demonstrated modest success. The relatively new area of mindfulness-based treatments has shown encouraging findings on bingeing and psychological variables for BED. There are as yet no known mindfulness-based treatment studies for BN. Further, proposed mindfulness components target the processes outlined in the Transdiagnostic Process Model of Binge Eating. The aim of the thesis was to investigate the effectiveness of a mindfulness group treatment for BN, BED, and ED-NOS. Measures of both primary (eating disorder behaviours) and secondary (psychological factors) variables were included, and clinical significance was assessed. A randomised-controlled trial was conducted, in which 126 females (aged 19 to 66 years) were randomly assigned to an eight session group-mindfulness treatment (n = 61) or waitlist condition (n = 65), of which 45 women completed the active treatment. Results showed that the mindfulness treatment resulted in significant reductions on both primary and secondary variables, with large effect sizes, compared to a Waitlist control group, with the exception of purging behaviours. A substantial proportion of participants evidenced clinically significant change, and mean post-treatment frequencies of bingeing and compensatory behaviours no longer met diagnostic criteria. These improvements were maintained at one-month follow-up. Pre to post treatment increases in mindfulness significantly predicted symptom change, whereas group cohesion and homework mindfulness practice was not significantly related to outcome. The findings of the current study have suggested that mindfulness may be an effective treatment for binge eating, and tentative support has been provided for the Transdiagnostic Process Model of Binge Eating.