Chapter 12: Bulimia Nervosa and Binge Eating Disorder

Linda W. Craighead

Margaret A. Martinez

Kelly L. Klump

DSM-5 Changes for Eating Disorders

DSM-IV-TR: Eating Disorders (EDs):Anorexia Nervosa (AN)Bulimia Nervosa (BN)Eating Disorder Not

Otherwise Specified (EDNOS)

Separate Chapter had Disorders Usually First Diagnosed During Infancy, Childhood, or Adolescence

DSM-5: Feeding and Eating Disorders (FED):Anorexia Nervosa (AN)Bulimia Nervosa (BN)Binge Eating Disorder

(BED); in DSM-IV-TR appendix as provisional

Other specified FEDUnspecified FED

- Avoidant/restrictive food intake disorder

- Pica

- Rumination Disorder

Rationale for Changes

Changes intended to:Reduce the frequency of the unspecified diagnosisEstablish criteria appropriate for clinical presentations at

younger agesThere is some concern that the new criteria may

dramatically increase the number of individuals diagnosed with an eating disorder

DSM-5 Diagnostic Criteria for BN

BULIMIA NERVOSA

A. Recurrent episodes of binge eating. Binge eating characterized by BOTH:1. Eating an objectively large amount of food, i.e. larger than most people would eat in a similar

period of time and under similar circumstances;

2. A sense of loss of control over eating during the episode.

B. Recurrent inappropriate compensatory behavior in order to prevent weight gain (e.g. self-induced vomiting, misuse of laxatives/diuretics/enemas/other medications)

C. Binge eating and inappropriate compensatory behaviors both occur, on average, at least once a week for three months

D. Self-evaluation is unduly influenced by body shape and weight.

E. The disturbance does not occur exclusively during episodes of Anorexia Nervosa

Indicates change from DSM-IV-TR criteria

Objective Binge Episode

To be classified as an objective binge episode (OBE), individual must:Consume an objectively large amount of food, that is

more than most people would eat in a similar situation and in a discrete period of time (e.g., 2 hours)• Objectively large ≈ 3x the typical portion for that food• 1,900 calories on average (Bartholome, Raymond, Lee, Peterson, & Warren, 2006)

Experience a subjective feeling of loss of control over eating

Subjective Binge Episode

Subjective binge episode (SBE):Individual experiences loss of control while eating an

amount of food considered normal or small• For example, one bowl of ice cream (SBE) versus a gallon of ice

cream (OBE)

700 calories on average (Bartholome, Raymond, Lee, Peterson, & Warren, 2006)

Only OBEs count toward frequency criterion for diagnosis of BN/BED

Characteristics of a Binge

Typically occur when individual is aloneMay be comprised of high-calorie foods (i.e., ice

cream) or healthy foods (i.e., carrots)Restricted intake before and after binge episodeCan be spontaneous or plannedTriggered by negative/positive emotions,

interpersonal stressors, presence of tempting food, violation of a dieting rule, body image dissatisfaction, excessive hunger, and so on

Obstacles to Treatment in BN

Bulimia is often not detected until later in the course of illness, often because:Binge/purge episodes feel habitual and are perceived as

problematicFunction of binge episodes as distracting from negative

emotionsConviction that stopping purging behaviors will lead to

weight gainShame and embarrassment associated with binge/purge

behaviors

Medical Complications of BN

Medical complications typically associated with purging

Complications include:Electrolyte abnormalitiesEsophageal/gastrointestinal symptomsMenstrual irregularitiesThyroid dysfunctionDental problemsEnlarged parotid glandsDecreased stomach motility

Proposed DSM-5 Diagnostic Criteria

BINGE EATING DISORDER

A. Recurrent episodes of binge eating. Binge eating characterized by both:1. Eating an objectively large amount of food, that is an amount larger than most people would eat in

a similar period of time and under similar circumstances

2. A sense of loss of control over eating during the episode

B. Binge eating episodes are associated with at least three of the following:1. Eating more rapidly than normal;

2. Eating until uncomfortably full;

3. Eating large amounts of food when not feeling physically hungry

4. Eating alone because of being embarrassed by how much one is eating

5. Feeling disgusted with oneself, depressed, or very guilty after overeating

C. Marked distress regarding binge eating is present

D. Binge eating occurs, on average, at least once a week for 3 months

E. The disturbance does not occur exclusively during episodes of anorexia nervosa and is not accompanied by inappropriate compensatory behaviors, as in bulimia nervosa.

**Indicates change from provisional DSM-IV-TR criteria

Distinction Between BN and BED

Both BN and BED require the presence of objectively large binge episodes (at least 1x/week for 3 months) in individuals who are not significantly underweightIn BED, no inappropriate compensatory behaviorsBED does not require concern about shape/weight,

although this is often reportedBoth BN and BED can be chronic conditions

exacerbated by life stressors

Medical complications of BED

Medical complications less common in BEDMost common complaint is gastrointestinal distress

associated with binge episodesIndividuals with BED are more often affected by

complications of comorbid obesityMany (but not all) individuals with BED are also

overweight/obeseThose individuals with BED who are not overweight are

at risk of developing obesity

History of Binge Eating

Ancient Greek

physicians describe ravenous hunger, or boulimos

James (1743) described

case accounts of

overeating at times

followed by vomiting

Stunkard et al. called

attention to night-eating syndrome (1955) and

binge eating syndrome

(1959)

Boskind-Lodahl and

White (1973) published feminist

formulation of “bulimarexia”

Russell (1979)

labeled this syndrome as

“bulimia nervosa”

DSM-5 (2013) recognizes

both BN and BED

Transdiagnostic Model of Eating Disorders

Proposed by Fairburn et al., a diagnostic approach that focuses on the similarities between various types of eating disordersViews overevaluation of eating, shape, and weight as the

core pathology underlying all eating disordersHypothesizes that overevaluation leads to

restriction/dieting that, in turn, leads to disordered eatingMay explain the high rate of diagnostic crossover in eating

disordersLimitations of the transdiagnostic model:

Many individuals with BED report onset of binge eating before development of weight concerns

EpidemiologyUsing DSM-IV criteria, prevalence of BN is ~0.5%

to1.0%Prevalence of any binge eating symptoms is 5.7%Using DSM-5 criteria, prevalence of BN is ~2%~90% of those diagnosed are women

Using DSM-IV criteria, prevalence of BED is ~2% to 5%Prevalence among individuals seeking weight-loss

interventions is higher, ~30%Using DSM-5 criteria, prevalence of BED is ~3.6% in women

and 2.1% in menMore equitable gender distribution (~65% female, 35% male)

Binge eating may be more common among certain minority groups

Course

Typical age of onset for BN is late adolescence/early adulthoodIndividuals with BN often have a history of AN (~10% to

14% of community samples, ~25% to 37% of clinical samples)

Onset of OBEs may be earlier than the age at which the individual meets full diagnostic criteria for BN or BED

Both BN and BED have a chronic course and high relapse rates

Comorbidity

Common Axis I cormorbidities include:Mood disorders

• Especially major depression and dysthymia

Anxiety disorders• Posttraumatic stress disorder is more common in BN and BED than

AN

Substance abuseCommon Axis II comorbidities include:

Borderline personality disorderAvoidant, dependent, histrionic, and paranoid personality

disorders

Genetic Risk Factors

AN, BN, and BED have moderate-to-large heritabilities, similar to biologically based illnessesIn girls, genetic risk activated during pubertyIn boys, genetic risk remains constant across the lifespanEstrogen may account for difference in pubertal risk

Some genes have been implicated, including serotonin, neurotrophic, estrogen receptor, and dopamine genes

Dieting and other environmental factors may increase genetic risk

Neurobiological Risk Factors

Overactivity in opioid and dopaminergic systems in binge eating resembles that seen in substance use

Neural patterns may vary over course of illnessHypothesized that overactive reward networks may

increase risk for developing binge eating……once binge eating develops, binge behaviors may

result in down-regulation and hyposensitivity of neural reward pathways

Personality Traits

ImpulsivityImpulsivity associated with binging and purgingImpulsivity abates with recovery

ObsessionalityIndividuals with eating disorders tend to have obsessive-

compulsive traitsPerfectionism

May mediate the relationship between eating disorders and obsessive-compulsive symptoms

Emotion Dysregulation

Binge eating conceptualized as emotion regulation strategy

Negative affect precedes and maintains onset of binge eatingNegative affect also associated with body dissatisfaction and

dieting behaviors, which may compound the relationship between negative affect and binge eating

Although binge eating may momentarily reduce negative affect, episode is often followed by increased negative affect

Compensatory behaviors may reduce negative affect and thus increase as a result of negative reinforcement

Cognitive Dysfunction

Cognitive symptoms of BN include:Appearance overvaluation

• Self-worth is disproportionately affected by body shape and weight

Internalization of the thin ideal• Thin cultural standard is fully adopted

Cognitive biases• Attention and memory biased towards information regarding food,

weight, and shape

Rigid and obsessive thinking patterns• Thinking characterized by strict and dichotomous patterns

Risk Factors

Body dissatisfactionLeads to negative affect and dieting behavior, which in turn

may produce disordered eatingDieting

Excessive caloric deprivation may trigger binge eatingInteroceptive awareness

Deficits in ability to monitor internal states predicts onset of eating disorder symptoms

Body massHigher body mass may contribute to disordered eating

through increased body dissatisfaction and dieting behaviors

Environmental Factors

Sociocultural pressureNo clear causal relationship between media exposure

and onset of eating disordersFamily

Family attitudes and behavior may contribute to thin ideal internalization and the failure to develop effective coping strategies

Childhood sexual abuseHistory of abuse is a risk factor for general

psychopathology, not specific to eating disorders

Assessment

Interview measure of eating disorder symptomsEating Disorder Examination (EDE): Assesses disordered

attitudes and behaviors over past 4 weeks• Four subscales assess restraint, concern about eating, concern

about shape, and concern about weight• Structured format ensures assessment of a variety of constructs

are assessed• Takes time to complete interview and the extensive training

required to use it limits use in clinical settings

Assessment, cont

Self-report measures of eating disorder symptomsQuestionnaire version of EDE (EDE-Q)

• Can be used for diagnostic purposes or to assess dimensions of eating pathology

Eating Disorder Inventory (EDI) and Bulimia Test–Revised (BULIT-R)• Global measures with multiple subscales, often used to assess

treatment outcome

Children’s Eating Attitudes Test (Ch-EAT)• Used to assess eating disorders in children

Treatment of BN

Psychological interventionsClinical trials have established Cognitive Behavioral Therapy

(CBT) and Interpersonal Therapy (IPT) as optimal treatments• Although CBT may initially be more effective, individuals receiving IPT

continue to show improvement over follow-up so no difference in long run

Interventions may be delivered in guided self-help format to increase treatment access

Pharmacological interventionsAntidepressant medications to prevent relapse when

medication stopped effective but best to use in combination with CBT

Further research required to determine best treatments for males, older women, and adolescents

Treatment of BED

Psychological interventionsAs with BN, CBT and IPT are effective treatmentsSelf-help treatments also effectiveBehavioral Weight Loss (BWL) often used to treat

comorbid obesity, but weight loss is minimalPharmacological interventions

Fluoxetine may reduce binge episodes in BED, as in BN, but does not contribute to weight loss

Topirimate thought to control impulsive tendenciesMedications do not seem to confer additional benefit

beyond psychotherapy

Prevention of Eating Disorders

Programs targeting high-risk individuals more effective than those implemented universally

Prevention programs generally effective in raising awareness of eating disordered symptoms, less effective in reducing risk factors

Novel programs capitalize on cognitive dissonance by asking participants to critique the thin ideal