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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