oxytocin and Bulimia-Nervosa

Eating disorders continue to be a major public health issue and important cause of morbidity and premature mortality, particularly for young people. Yet in a concerning dialectic, this occurs in the context of an epidemic of obesity which, with its medical complications, constitutes another vexing public health challenge. While it is not an eating disorder per se obesity is often comorbid with eating disorders. Effective treatment for both eating disorders and obesity has proven to be elusive and in the search for novel therapeutic interventions, the prosocial, anxiolytic, brain plasticity and metabolic effects of oxytocin (OT) have been examined from this perspective. The availability of intranasal oxytocin (IN-OT) has led to a number of interventional treatment studies in anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), their atypical and subclinical forms and in medical and psychiatric conditions co-occurring or comorbid with these, obesity with BED would be included here. The aim of this mini review is to collate recent findings on OT as a novel therapeutic intervention in eating disorders and obesity and to identify and address some of the knowledge gaps in the use of IN-OT. The wider clinical perspective utilised here might better address some of the gaps and identify future directions of research. Clearly much remains to be done for OT to fulfil its therapeutic promise in eating disorders. OT might yet be of therapeutic promise and will be appreciated where treatment advances have been hard to come by and prevention challenging for these disorders.

Topics: Anorexia Nervosa; Binge-Eating Disorder; Bulimia Nervosa; Feeding and Eating Disorders; Humans; Obesity; Oxytocin

The neurohormone oxytocin (OXT) impacts food intake as well as cognitive, emotional, and social functioning-all of which are central to eating disorder (ED) pathology across the weight spectrum. Here, we review findings on endogenous OXT levels and their relationship to ED pathology, the impact of exogenous OXT on mechanisms that drive ED presentation and chronicity, and the potential role of genetic predispositions in the OXT-ED link.. Current findings suggest a role of the OXT system in the pathophysiology of anorexia nervosa. In individuals with bulimia nervosa, endogenous OXT levels were comparable to those of healthy controls, and exogenous OXT reduced food intake. Studies in other ED are lacking. However, genetic studies suggest a broad role of the OXT system in influencing ED pathology. Highlighting findings on why OXT represents a potential biomarker of and treatment target for ED, we advocate for a systematic research approach spanning the entire ED spectrum.

Topics: Anorexia Nervosa; Body Weight; Bulimia Nervosa; Feeding and Eating Disorders; Humans; Neuropeptides; Oxytocin

Advances in the treatment of bulimia nervosa and binge-eating disorder (BN/BED) have been marred by our limited understanding of the underpinning neurobiology. Here we measured regional cerebral blood flow (rCBF) to map resting perfusion abnormalities in women with BN/BED compared with healthy controls and investigate whether intranasal oxytocin (OT), proposed as a potential treatment, can restore perfusion in disorder-related brain circuits. Twenty-four women with BN/BED and 23 healthy women participated in a randomized, double-blind, crossover, placebo-controlled study. We used arterial spin labelling MRI to measure rCBF and the effects of an acute dose of intranasal OT (40 IU) or placebo over 18-26 min post dosing, as we have previously shown robust OT-induced changes in resting rCBF in men in a similar time-window (15-36 min post dosing). We tested for effects of treatment, diagnosis and their interaction on extracted rCBF values in anatomical regions-of-interest previously implicated in BN/BED by other neuroimaging modalities, and conducted exploratory whole-brain analyses to investigate previously unidentified brain regions. We demonstrated that women with BN/BED presented increased resting rCBF in the medial prefrontal and orbitofrontal cortices, anterior cingulate gyrus, posterior insula and middle/inferior temporal gyri bilaterally. Hyperperfusion in these areas specifically correlated with eating symptoms severity in patients. Our data did not support a normalizing effect of intranasal OT on perfusion abnormalities in these patients, at least for the specific dose (40 IU) and post-dosing interval (18-26 min) examined. Our findings enhance our understanding of resting brain abnormalities in BN/BED and identify resting rCBF as a non-invasive potential biomarker for disease-related changes and treatment monitoring. They also highlight the need for a comprehensive investigation of intranasal OT pharmacodynamics in women before we can fully ascertain its therapeutic value in disorders affecting predominantly this gender, such as BN/BED.

Topics: Binge-Eating Disorder; Brain; Bulimia Nervosa; Cross-Over Studies; Double-Blind Method; Female; Humans; Male; Oxytocin; Perfusion

The current study aimed to test the influence of oxytocin on palatable food intake, 24-h 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-h 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.

Topics: Binge-Eating Disorder; Bulimia Nervosa; Double-Blind Method; Energy Intake; Feeding Behavior; Female; Humans; Hydrocortisone; Linear Models; Oxytocin; Saliva; Stress, Psychological; Visual Analog Scale; Young Adult

Bulimia nervosa (BN) is characterized by binge eating and emotional dysregulation including increased negative affectivity (anger, anxiety). The aim of this study was to examine the effect of oxytocin on attentional processes towards anger in patients with BN.. The study design consisted of a double-blind, placebo-controlled within-subject crossover, single dose experiment. Sixty-four women (31 patients with BN and 33 healthy comparisons) completed self-reported measures to evaluate emotional difficulties and were administered a single dose of intranasal oxytocin (40IU) or placebo followed by a visual probe detection task to examine attentional orienting to angry or happy faces.. Patients with BN reported higher emotional dysregulation and more difficulties in controlling anger compared to the healthy comparison group. Patients with BN and the healthy women exhibited similar attentional bias to angry faces in the placebo condition. Intranasal oxytocin reduced the attentional bias towards angry faces in both the BN patients and the healthy women.. We found that a single dose of oxytocin reduced vigilance towards angry faces in patients with BN as well as healthy women. The results showed that patients with BN are not different from healthy women in terms of vigilance towards threat.

Topics: Administration, Intranasal; Adult; Anger; Anxiety; Anxiety Disorders; Attention; Attentional Bias; Bulimia Nervosa; Cross-Over Studies; Double-Blind Method; Emotions; Facial Expression; Female; Humans; Oxytocin; Pattern Recognition, Visual; Reaction Time; Young Adult

Social difficulties and problems related to eating behaviour are common features of both anorexia nervosa (AN) and bulimia nervosa (BN). The aim of this study was to examine the impact of intranasal oxytocin on consummatory behaviour and emotional recognition in patients with AN and BN in comparison to healthy controls.. A total of 102 women, including 35 patients with anorexia nervosa (AN), 34 patients with bulimia nervosa (BN), and 33 healthy university students of comparable age and intelligence, participated in a double-blind, single dose placebo-controlled cross-over study. A single dose of intranasal administration of oxytocin (40 IU) (or a placebo) was followed by an emotional recognition task and an apple juice drink. Food intake was then recorded for 24 hours post-test.. Oxytocin produced no significant change in appetite in the acute or 24 hours free living settings in healthy controls, whereas there was a decrease in calorie consumption over 24 hours in patients with BN. Oxytocin produced a small increase in emotion recognition sensitivity in healthy controls and in patients with BN, In patients with AN, oxytocin had no effect on emotion recognition sensitivity or on consummatory behaviour.. The impact of oxytocin on appetite and social cognition varied between people with AN and BN. A single dose of intranasal oxytocin decreased caloric intake over 24 hours in people with BN. People with BN showed enhanced emotional sensitivity under oxytocin condition similar to healthy controls. Those effects of oxytocin were not found in patients with AN.. ClinicalTrials.gov KCT00000716.

Topics: Administration, Intranasal; Adolescent; Adult; Analysis of Variance; Anorexia Nervosa; Bulimia Nervosa; Cross-Over Studies; Emotions; Facial Expression; Feeding and Eating Disorders; Feeding Behavior; Female; Humans; Oxytocin; Young Adult

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 characterising 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.. The present study employed a single-session cross-over design to test the hypothesis that a divided dose of 64 IU of intranasal oxytocin, administered as one intranasal dose of 40 IU of oxytocin followed by a top-up of 24 IU of oxytocin 80 minutes later, vs 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 vs 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.. In contrast to our hypothesis, there was no main effect of diagnosis on attentional bias to food (fixed effect = 5.70, P = 0.363), nor a significant interaction between diagnosis and drug condition (fixed effect =-14.80, P = 0.645). There was a main effect of drug condition, such that oxytocin increased vigilance towards food vs neutral images in the dot probe task (fixed effect = 10.42, P = 0.044). 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.. The findings of the present study 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.

Topics: Administration, Intranasal; Adolescent; Adult; Attentional Bias; Binge-Eating Disorder; Bulimia Nervosa; Cross-Over Studies; Female; Food; Humans; Oxytocin; Photic Stimulation; Pilot Projects; Young Adult

Published studies suggested an implication of oxytocin in some temperament characteristics of personality. Therefore, we measured oxytocin secretion in 23 women with anorexia nervosa (AN), 27 with bulimia nervosa (BN) and 19 healthy controls and explored the relationships between circulating oxytocin and patients' personality traits. Plasma oxytocin levels were significantly reduced in AN women but not in BN ones. In healthy women, the attachment subscale scores of the reward dependence temperament and the harm avoidance (HA) scores explained 82% of the variability in circulating oxytocin. In BN patients, plasma oxytocin resulted to be negatively correlated with HA, whereas no significant correlations emerged in AN patients. These findings confirm a dysregulation of oxytocin production in AN but not in BN and show, for the first time, a disruption of the associations between hormone levels and patients' temperament traits, which may have a role in certain deranged behaviours of eating disorder patients.

Topics: Adolescent; Adult; Anorexia Nervosa; Bulimia Nervosa; Case-Control Studies; Female; Humans; Oxytocin; Temperament; Young Adult

Oxytocin circuits are implicated in the regulation of appetite and weight. Variants in the oxytocin receptor (OXTR) gene have been associated with bulimic behaviour. This study aimed to investigate the association between the OXTR gene and eating disorders.. We genotyped six single nucleotide polymorphisms, rs53576, rs237879, rs2228485, rs13316193, rs2254298 and rs1042778, located within the OXTR gene in Korean patients with eating disorders using the single-base extension method. We studied a total of 262 women, including 69 patients with anorexia nervosa, 90 patients with bulimia nervosa (BN), and 103 healthy women.. We found a positive association between the G allele of OXTR rs53576 and BN. In the BN group, the G carriers showed a high score on the behavioural inhibition system.. These findings suggest the involvement of the oxytocinergic system in the mechanism that underlies BN.

Topics: Adult; Anorexia Nervosa; Body Weight; Bulimia Nervosa; Female; Genotype; Humans; Middle Aged; Oxytocin; Polymorphism, Single Nucleotide; Receptors, Oxytocin; Young Adult