Reevaluating Cue Exposure and Response Prevention in a Pilot Study: An Updated Treatment for Binge Eating Disorder

Modified cue exposure for adolescents with binge eating behaviour: study protocol of a randomised pilot trial called EXI(ea)T

INTRODUCTION

Binge eating (BE) behaviour is highly prevalent in adolescents, and can result in serious metabolic derangements and overweight in the long term. Weakened functioning of the behavioural inhibition system is one potential pathway leading to BE. Food cue exposure focusing on expectancy violation (CE_EV) is a short intervention for BE that has proven effective in adults but has never been tested in adolescents. Thus, the current randomised pilot trial evaluates the feasibility of CE_EV for adolescents and its efficacy in reducing eating in the absence of hunger (EAH) of binge food items.

METHODS AND ANALYSIS

The trial will include N=76 female adolescents aged between 13 and 20 years with a diagnosis of bulimia nervosa, binge eating disorder (BED) or their subthreshold forms based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Participants will be randomly assigned to two sessions of CE_EV or behavioural analysis (BA), a classical cognitive-behavioural therapy-based intervention. The primary endpoint is the change in EAH measured according to ad libitum consumption of personally preferred binge food in a bogus taste test at post-test based on the intention-to-treat population. Key secondary endpoints are changes in EAH of standardised binge food at post-test, in EAH at 3-month follow-up (FU) and in food craving after induction of food cue reactivity at post-test and FU. To identify further valid outcome parameters, we will assess effects of CE_EV compared with BA on global ED psychopathology, BE frequency within the last 28 days, body weight, response inhibition and emotion regulation abilities. Treatment groups will be compared using analysis of covariance with intervention as fixed factor and body mass index at baseline as covariate.

ETHICS AND DISSEMINATION

This clinical trial has been approved by the Ethics Review Committee of the Medical Association of Rhineland-Palatinate and the Medical Faculty of the Ruhr-University Bochum. The collected data will be disseminated locally and internationally through publications in relevant peer-reviewed journals and will be presented at scientific and clinical conferences. Participants data will only be published in an anonymised form.

TRIAL REGISTRATION NUMBER

DRKS00024009.

A mechanistic staging model of reward processing alterations in individuals with binge-type eating disorders

Altered reward processing is thought to characterize binge-type eating disorders, but the exact nature of these alterations is unclear. A more fine-grained understanding of whether specific aspects of reward processing contribute to the development or maintenance of binge eating may point to new therapeutic targets and personalized treatments. The incentive sensitization theory of addiction proposes that repeated use of a substance increases the desire to approach a reward ('wanting') but not pleasure when consuming the reward ('liking'), suggesting that reward processes driving addiction change over time. We hypothesize that the same may be true for binge eating. Further, consistent with the maladaptive scaling hypothesis, reward processing may be heightened for multiple reinforcers in at-risk individuals but become tuned toward food once binge eating is initiated. In this article, we propose a mechanistic staging model of reward processing in binge-type eating disorders that synthesizes existing data and posits that alterations of reward processing depend on illness stage and reward type. We outline translational methods for testing key hypotheses and discuss clinical implications. Considering reward processing alterations in relation to illness stage has the potential to improve treatment outcomes by ensuring that the mechanisms targeted are personalized to the individual patient. PUBLIC SIGNIFICANCE: Individuals with binge-type eating disorders experience alterations in their desire for, and pleasure from, food. We believe that the exact nature of these alterations in reward processing change over the course of illness-from the at-risk state to an established illness. If true, treatments for binge-type eating disorders that target reward processing should be personalized to the illness stage of the patient.