Binge Eating Disorder

Binge eating disorder is a psychiatric eating disorder characterised by recurrent episodes of binge eating, occurring at least weekly over a sustained period. A binge is consumption of an objectively large amount of food within a discrete period, with a subjective sense of loss of control.

It occurs without the regular compensatory purging or restrictive behaviour of bulimia nervosa or anorexia nervosa. It is the commonest specific eating disorder overall.

It is frequently, though not universally, associated with overweight or obesity, because there is no compensatory behaviour. The medical risk relates mainly to the metabolic consequences of the eating pattern, not to the malnutrition or purging related complications of the other major eating disorders.

Pathophysiology

• Binge eating episodes share proposed psychological mechanisms with those described under bulimia nervosa, including mood regulation function and loss of normal inhibitory control over eating.
• There is no subsequent compensatory behaviour. Sustained binge eating therefore contributes to a net positive caloric balance, with weight gain in the majority of, though not all, affected individuals.
• The condition carries significant psychological distress and impaired quality of life, independent of weight status.
• This matters because the condition has historically been viewed through its metabolic and weight related consequences. The binge eating pattern itself causes significant, independent psychological morbidity.

• Recurrent binge eating episodes characterise the core behavioural and psychological pattern.
• Episodes are typically associated with eating more rapidly than normal, eating until uncomfortably full, and eating large amounts when not physically hungry.
• Patients often eat alone because of embarrassment about the quantity eaten, and feel disgusted, depressed or guilty afterwards.
• Unlike bulimia nervosa, there is no regular compensatory behaviour (vomiting, laxative misuse, excessive exercise) after binges.
• Body weight is therefore frequently, though not invariably, in the overweight or obese range. Where it is, there is a risk of the recognised medical complications of excess weight: type two diabetes, hypertension, dyslipidaemia and other components of the metabolic syndrome.
• Significant psychological distress, shame and impaired quality of life related to the binge eating pattern itself are important components of the presentation. Depression and anxiety frequently coexist.
• This psychological burden warrants direct clinical attention, independent of any weight related medical assessment.

• Diagnosis rests on a detailed clinical history of the pattern and frequency of binge eating episodes and the associated psychological features.
• Confirm the absence of regular compensatory behaviour, which distinguishes the condition from bulimia nervosa. The general principles are those detailed under eating disorders.
• Assess for metabolic complications where clinically indicated, relevant to the individual's weight status and risk profile. Screen for type two diabetes, hypertension and dyslipidaemia, following standard principles for the broader overweight and obese population.
• Screen for coexisting depression and anxiety, given the frequent association and the significant, independent psychological burden of the condition.
• Ask directly and sensitively about weight stigma and previous unsuccessful dieting attempts. Both are common contributing and perpetuating factors.

• Cognitive behavioural therapy adapted for binge eating disorder is the first line, most strongly evidence supported psychological treatment. It addresses the binge eating pattern and its psychological drivers.
• Structured, guided self help cognitive behavioural approaches also show efficacy. They are a more accessible, lower intensity option, particularly suitable as an initial step given resource constraints in many services.
• Lisdexamfetamine, a stimulant, is approved for moderate to severe binge eating disorder in some jurisdictions. It reduces binge eating frequency but needs the standard stimulant safety checks: cardiovascular assessment and monitoring for misuse potential.
• Topiramate has shown efficacy in clinical trials, with the generally welcome effect of modest weight loss. It is a further pharmacological option, particularly where significant obesity coexists.
• Consider the adverse effect profile of topiramate, including cognitive slowing. Teratogenicity requires effective contraception counselling in women of childbearing potential.
• Manage psychological distress and any coexisting depression or anxiety by standard principles, alongside the eating disorder focused treatment. Mood and binge eating are closely interrelated.
• A weight neutral, non-stigmatising approach is generally recommended as the initial framework. It focuses on the binge eating pattern and associated distress, not primarily on weight loss.
• A premature or excessive focus on weight loss in isolation can perpetuate the eating disorder psychopathology and shame.
• Any weight management intervention, where clinically relevant and desired by the patient, is better addressed once the binge eating pattern has been meaningfully treated.