• Are Trans diagnostic models of eating disorders fit for purpose? A consideration of the evidence for food addiction

      Treasure, Janet; Leslie, Monica; Chami, Rayane; Fernández-Aranda, Fernando; King's College London; University Hospital of Bellvitge and CIBERobn (ISCIII)
      Explanatory models for eating disorders have changed over time to account for changing clinical presentations. The transdiagnostic model evolved from the maintenance model, which provided the framework for cognitive behavioural therapy for bulimia nervosa. However, for many individuals (especially those at the extreme ends of the weight spectrum), this account does not fully fit. New evidence generated from research framed within the food addiction hypothesis is synthesised here into a model that can explain recurrent binge eating behaviour. New interventions that target core maintenance elements identified within the model may be useful additions to a complex model of treatment for eating disorders.
    • The Influence of Oxytocin on Eating Behaviours and Stress in Women with Bulimia Nervosa and Binge Eating Disorder

      Leslie, Monica; Leppanen, Jenni; Paloyelis, Yannis; Treasure, Janet; King's College London (Elsevier, 2018-12-21)
      The current study aimed to test the influence of oxytocin on palatable food intake, 24-hour caloric consumption, and stress in women with bulimia nervosa and binge eating disorder. We recruited 25 women with DSM-5 bulimia nervosa or binge eating disorder, and 27 weight-matched comparison women without history of an eating disorder. We employed a double-blind, placebo-controlled crossover design in which each participant attended the lab for two experimental sessions, receiving a divided dose of 64IU intranasal oxytocin in one session and equivalent volume of placebo nasal spray in the opposite session. The order of administration was pseudo-randomised across participants. We hypothesised that a divided dose of 64IU intranasal oxytocin administration would reduce subjective hunger, the immediate consumption of palatable food, 24-hour calorie consumption, and the incidence of binge eating when compared to placebo. We also hypothesised that oxytocin administration would be associated with lower levels of stress and salivary cortisol, and that there would be an interaction with participant group such that oxytocin would reduce eating behaviour and stress to a greater degree in women with bulimia nervosa or binge eating disorder, compared to women without history of an eating disorder. We did not find a significant effect of oxytocin on any of the measurements of eating behaviour, subjective stress, or salivary cortisol. We recommend that future studies test the dose-response effect of oxytocin on eating behaviours and stress in human populations with eating disorders to further clarify the moderating factors for oxytocin’s effect on eating.
    • The Influence of Oxytocin on Risk-Taking in the Balloon Analogue Risk Task Among Women with Bulimia Nervosa and Binge Eating Disorder

      Leslie, Monica; Leppanen, Jenni; Paloyelis, Yannis; Nazar, Bruno; Treasure, Janet; King's College London; Federal University of Rio de Janeiro
      Previous theoretical models of bulimia nervosa (BN) and binge eating disorder (BED) have implicated cross-domain risk-taking behaviour as a significant maintenance factor in both disorders. The current study sought to test this hypothesis by administering the Balloon Analogue Risk Task (BART) to 25 women with BN or BED and 27 healthy comparison women without history of an eating disorder. Furthermore, we tested the effect of a divided dose of 64IU oxytocin on risk-taking behaviour in the BART. Contrary to our hypothesis, women with BN or BED did not exhibit baseline differences in performance on the BART in the placebo condition (t = 1.42, df = 50, p = .161, d = 0.39). Oxytocin did not have a main effect on performance in the BART (F = 0.01, df = 1, p = .907, η2partial < .001); however, there was an interaction such that participants in the BN/BED participant group, compared to the healthy comparison group, demonstrated safer behaviour on the BART specifically in the oxytocin condition, but not in the placebo condition (F = 4.29, df = 1, p = .044, η2partial = .082). These findings cast doubt on the common assumption that individuals with BN and BED exhibit greater risk-taking behaviour in all domains and add to evidence that oxytocin plays a functional role in modulating behaviours which entail trade-offs between reward approach and risk in humans. We recommend that future dose-response studies further investigate the effect of oxytocin on reward approach behaviour in women with recurrent binge eating behaviour and the clinical significance of this effect.
    • A Pilot Study Investigating the Influence of Oxytocin on Attentional Bias to Food Images in Women with Bulimia Nervosa or Binge Eating Disorder

      Leslie, Monica; Leppanen, Jenni; Paloyelis, Yannis; Treasure, Janet; King's College London
      Background: Previous research has found that exogenous oxytocin administration has the potential to modulate attentional biases in women with anorexia nervosa. Recent work has indicated that attentional biases to food may reinforce the recurrent binge eating behaviour which characterises bulimia nervosa and binge eating disorder. To date, however, no study has yet investigated the effect of oxytocin on attentional biases to palatable food in women with bulimia nervosa and binge eating disorder. Methods: This study employed a single-session crossover design to test the hypothesis that a divided dose of 64IU intranasal oxytocin, administered as one intranasal dose of 40IU oxytocin followed by a top-up of 24IU oxytocin 80 minutes later, versus placebo administration administered in the same dosing schedule, would reduce attentional biases towards food images in a dot probe task. We hypothesised that oxytocin administration would reduce vigilance towards food to a greater degree in women with bulimia nervosa or binge eating disorder, versus healthy comparison women. Twenty-five women with bulimia nervosa or binge eating disorder and 27 comparison women without history of an eating disorder were recruited to take part in the study. Results: Contrary to our hypothesis, there was no main effect of diagnosis on attentional bias to food (fixed effect = 5.70, p = .363), nor a significant interaction between diagnosis and drug condition (fixed effect = -14.80, p = .645). There was a main effect of drug condition, such that oxytocin increased vigilance towards food, versus neutral, images in the dot probe task (fixed effect = 10.42, p = .044). A correlation analysis revealed that this effect was moderated by attentional bias in the placebo condition, such that greater avoidance of food stimuli in the placebo condition was associated with a greater increase in vigilance induced by oxytocin. Conclusion: The current findings add to a mixed body of literature investigating the therapeutic effects of oxytocin in women. Future research would benefit from dose-response studies investigating the optimal dose of oxytocin for modulating the attentional processing of palatable food in populations with eating disorders.
    • Testing the addictive appetite model of binge eating: The importance of craving, coping, and reward enhancement

      Leslie, Monica; Turton, Robert; Burgess, Emilee; Nazar, Bruno; Treasure, Janet; King's College London; University of Alabama at Birmingham; Federal University of Rio de Janeiro
      In the current study, we examine components of the “addictive appetite” model of recurrent binge eating. Specifically, we tested the influence of addictive processes and the influence of emotional regulation processes on recurrent binge eating behaviour. We recruited 79 women in total for the current study; 22 with bulimia nervosa, 26 weight-matched lean comparison women, 15 women with binge eating disorder, and 16 weight-matched overweight/obese comparison women. Participants completed questionnaire assessments of food craving and motivations for eating. Compared to weight-matched comparison women, women with binge-type eating disorders endorse significantly greater levels of food craving, eating for purposes of coping, and eating for purposes of reward enhancement. A cluster analysis revealed that these three traits distinguish women with binge-type eating disorders from weight-matched comparison women. These findings provide support for the addictive appetite model of binge eating behaviour, and highlight addictive and emotional regulation processes as potential targets for treatment.
    • Towards a Translational Approach to Food Addiction: Implications for Bulimia Nervosa

      Leslie, Monica; Lambert, Ellen; Treasure, Janet; King's College London
      Purpose of review: In recent years, the food addiction hypothesis of loss-of-control eating has gained traction in the field of eating disorders. In particular, the neural process of food addiction plays a dominant role in the recently formulated “addictive appetite” model of bulimia nervosa and binge eating disorder. Nonetheless, several components of the food addiction hypothesis, including the presence of withdrawal and tolerance effects, as well as the proposition that some foods possess “addicting” properties, remain highly controversial. In response, the current review synthesises existing evidence for withdrawal and tolerance effects in people with bulimia nervosa. Recent findings: The recent development of a validated tool to measure withdrawal from highly processed foods will aid in measuring withdrawal symptoms and testing hypotheses related to withdrawal in the context of food addiction. We subsequently describe preclinical and human evidence for a central insulin- and dopamine-mediated pathway by which recurrent loss-of-control binge eating is maintained in bulimia nervosa. Summary: Evidence in populations with bulimia nervosa and loss-of-control eating provides preliminary support for the role of food addiction in the maintenance of bulimia nervosa. Future longitudinal research is needed to develop a clearer profile of illness progression and to clarify the extent to which dysregulation in glucose metabolism contributes to food craving and symptom maintenance in bulimia nervosa.
    • The use of a positive mood induction video-clip to target eating behaviour in people with bulimia nervosa or binge eating disorder: An experimental study

      Cardi, Valentina; Leppanen, Jenni; Leslie, Monica; Esposito, Mirko; Treasure, Janet; King's College London; University College London
      Recent theoretical models and empirical research have indicated that momentary negative affect increases the likelihood of binge eating episodes for individuals with bulimia nervosa and binge eating disorder. However, relatively little research has explored the potential for positive mood to serve a protective effect in reducing the likelihood of overeating behaviour in bulimia nervosa and binge eating disorder. The current study included 30 women with bulimia nervosa or binge eating disorder in a within-subjects crossover design. Following exposure to a video designed to induce food craving, we found that a positive mood vodcast was associated with significantly lower levels of negative mood and food consumption in a taste test meal, when compared to a neutral vodcast (p = .002). These findings support a role for decreasing negative mood in reducing the likelihood of binge eating behaviour in women with bulimia nervosa and binge eating disorder.