Binge Eating Disorder – Diagnosis and Management

DSM-V Diagnostic Criteria [APA, 2013]

1.Recurrent episodes of binge eating:

• Eating a larger than normal volume of food within a set period of time
• Eating until uncomfortably full

2.Required to be specifically associated with at least 3 of the following:

• Rapid eating
• Eating until uncomfortably full
• Eating when not hungry
• Eating alone due to embarrassment
• Feelings of disgust and guilt about overeating

3.Marked Distress

4. Episodes of binge eating occurs:

• A minimum of 2 days per week over a 6-month period (DSM-IV)
• A minimum of 1 day per week over a 3-month period (DSM-V)

5.Binge eating does not include the following:

• Purging
• Fasting
• Excessive levels of exercise

Furthermore, the DSM-V has a severity grading (episodes per week), which includes mild (1 to 3), moderate (4 to 7), severe (8 to 13), extreme (≥14).

The assessment for a BED diagnosis is not quantitative; there is a subjective difficulty to overcome. A BED diagnosis is challenging due to the wide spectrum of people that BED affects and the difficulty patients have in distinguishing what is typical and atypical.

BED is associated with a high degree of psychiatric comorbidity, namely anxiety disorders (65%), mood disorders (46%), impulse control disorders (43%) or substance use disorders (23%).

Almost 50% of patients with BED have ≥ 3 comorbidities. [Citrome et al., 2015]

A systematic review showed that BED  is frequently comorbid with mood and anxiety disorders, as well as substance use disorders, each correlating with more severe manifestations of BED. Other psychiatric conditions commonly associated with BED include stress and adjustment-related disorders, impulse control disorders, ADHD, various personality disorders, and behavioural disorders.

Moreover, disorders related to bodily distress and perception, as well as psychotic disorders, have also shown significant associations with BED. There is also a reported link between BED and both suicidality and sleep disorders. [Kowalewska et al, 2024].

In addition, BED can evolve into anorexia nervosa or bulimia nervosa and vice versa. [Stice et al., 2013], [Allen et al., 2013]

Overall, there are several discrepancies between self-report results and investigator-based interviews. Clinicians are therefore required to detect what is objective and what is subjective, which can be done using the following, among others, eating disorder pathology assessments:

• Eating Disorder Examination (EDE) – An expert semi-structured interview that analyses the psychopathology of eating disorders including dietary restraint, eating concern, weight concern, and shape concern. [Fairburn  and Beglin, 1994], [Reas et al.,2006]
• Eating Disorder Inventory (EDI-3)– A standardised self-report measuring tool that analyses psychiatric symptoms associated with eating disorders in the general population. The EDI includes items on asceticism, body dissatisfaction, emotional dysregulation, social insecurity, and self-esteem. [Clausen et al.,2011]
• Binge Eating Scale (BES) – One of the most commonly used screening tools for detecting clinically significant binge eating behaviours. This validated and reliable structured clinical interview can also report on emotional and cognitive processes implicated in binge eating. [Timmerman,1999]
• Structured Interview for Anorexic and Bulimic Syndromes (SIAB-EX) – A reliable diagnostic assessment that has a wider approach to the EDE. The SIAB involves a semi-structured interview process that analyses general psychopathology (depression, anxieties, and phobias) as well as disordered eating. Also, it assesses and compares the current symptom expression with a patient’s historical expression of symptom. [Fichter et al., 2001]
• Three Factor Eating Questionnaire (TFEQ) – Published in 1985, this 51-item questionnaire separately measures the 3 domains of human eating behaviour: cognitive and behavioural restraint strategies towards eating, compulsive food intake, and hunger. [Stunkard and Messick, 1985]

Nevertheless, there is an element of detection bias with several individuals not quite meeting all of the BED criteria for a diagnosis. These are diagnosed as subthreshold BED:

• The sense of losing control (termed loss of control [LOC] eating) during an episode is a key diagnostic criterion of BED.
• However, LOC is also a subclinical diagnosis for patients that display LOC features but do not meet all of the criteria for BED.

For instance, post-bariatric surgery patients and children both have smaller stomachs and therefore cannot meet criteria 1a.

LOC eating is therefore used to describe binge eating episodes that involve a marked increase in the mean size and content that is contraindicated to that population subgroup. Engagement in LOC eating has been reported in:

• Up to 25% in post-bariatric surgery patients [Colles et al., 2008]
  
• Up to 32% in children who have a high risk of adult obesity [De Zwaan et al., 2010]

A summary of assessment and management is summarised in the following infographic.

There is strong evidence for the therapeutic treatment of BED.

Clinicians that regularly encounter patients with mood, anxiety, or substance abuse disorders are ideally placed to assess, diagnose, and apply eating disorder interventions.

Pharmacotherapy

The primary aim of the management of BED is to reduce the frequency of binge eating episodes and to achieve a state of abstinence. Given that many patients are also overweight or obese, then sustainable weight loss is also a target.

• Second-generation antidepressants – The most studied are fluoxetine (average dose: 71.3 mg/day) and fluvoxamine (average dose: 239 mg/day), which have been shown to reduce binge episode frequency as well as reduce BMI. Sertraline and citalopram have also shown similar efficacy profiles. [Crow, 2014]
• Anticonvulsants –  Topiramate (average dose: 212 mg/day) improved binge eating compulsion scores as well as significantly reducing binge days per week. Zonisamide (average daily dose of 436 mg /day) was also shown to be effective with weight loss.  [Crow, 2014]
• Sibutramine – A drug marketed for obesity that has shown reductions in binge frequency and self-reported depression at an average dose of 15 mg/day compared to placebo. Sibutramine was withdrawn from the US due to the risk of cardiovascular events. [Appolinario et al., 2003]
• Lisdexamfetamine dimesylate – Is the only FDA approved agent for BED. The recommended starting dose is 30 mg/day, which is gradually titrated to a target dose of 50-70mg/day. [Citrome et al., 2015]

Lisdexamfetamine (LDX) treatment in moderate to severe binge eating disorder (BED) has shown substantial symptom reduction or remission in 97% of patients after eight weeks, as observed through fMRI imaging. Interestingly, the neural connectivity changes linked to LDX improvement displayed minimal overlap with those traditionally distinguishing BED patients from healthy controls. LDX appears to exert its effect by targeting the interoceptive network, crucial for internal state awareness, which addresses the primary symptom of control loss in BED. [Donnelly & Hay , 2024]

Behavioural therapy

Behavioural weight loss (BWL)

• Behavioural weight loss has been shown to diminish the frequency of binge eating and may lead directly to weight loss.
• The extent of weight loss is limited (5–10% is commonly observed) and the maintenance of this weight loss is difficult.

Psychological Therapy

Cognitive Behavioural Therapy

• CBT for BED is a method that attempts to restructure patient’s binge-triggering thoughts for inappropriate food consumption by modifying psychological aspects such as inaccurate body shape and image beliefs. CBT can also facilitate weight loss and improve weight management in the long term. [Bulik et al., 2007]
• CBT reduces binge frequency, psychological aspects of binge eating, depressed mood and ratings of illness severity.
• CBT may also increase the likelihood of abstinence.

Dialectical Behaviour Therapy

• DBT for BED aims to improve mindfulness and emotional regulation that provides the patient with principles such as mindful eating, interpersonal effectiveness, and distress tolerance.
• DBT was studied in a 20 week trial and compared against a wait-list control in 44 women. DBT resulted in a greater reduction in binge days and binge episodes as well as reduction in weight, shape and eating concerns. [Telch et al., 2001]
• However, there does not seem to be a long term impact of DBT in BED. [Safer and Jo, 2010]

Interpersonal psychotherapy

• A form of psychodynamic therapy that focuses on a patient’s current relationships and can improve psychosocial and interpersonal functioning. Research shows that it has equivalent effectiveness as CBT at reducing binge episode frequency.

CBT in combination with a weight loss drug such as orlistat has shown greater efficacy than CBT plus placebo. [Grilo et al., 2005]

Augmentation of CBT with certain medications may provide additional benefit over CBT alone or medication alone.  The long term benefit of combined approaches remains to be studied. [Bulik et al., 2007]

A recent systematic review and meta-analysis showed that among adults with BED, there is strong evidence that therapist-led CBT, lisdexamfetamine, and second generation antidepressants (mainly selective serotonin reuptake inhibitors) reduce the frequency of binge eating, increase the likelihood of achieving abstinence from binge eating, and improve other eating-related psychological outcomes. [Brownley et al., 2016]

BED is a distinct eating disorder which is associated with marked functional impairment and psychological distress. It is highly comorbid with other psychiatric conditions.

BED may go undetected for many years as patients do not specifically complain about their eating behaviours and clinicians may not ask about eating behaviours.

Further research is required to elucidate the neurobiology of BED along with the optimal medication and psychological approaches for BED.