eating disorders

Chapter 9: Eating Disorders

Learning Objectives

• 9.1 Identify the clinical aspects of the three major eating disorders.

• 9.2 Compare and contrast the symptoms and diagnostic criteria across the DSM-5 eating disorders.

• 9.3 Explain the diagnostic crossover that typically occurs with eating disorders.

• 9.4 Explain the risk and causal factors of eating disorders.

• 9.5 Discuss how eating disorders are treated.
  NOTE: We will not cover the obesity section of this chapter.

DSM-5 Section on Feeding and Eating Disorders

• Feeding Disorders

  • Pica

  • Rumination Disorder

  • Avoidant/Restrictive Food Intake Disorder

• Eating Disorders

  • Anorexia Nervosa

  • Bulimia Nervosa

  • Binge-Eating Disorder

  • Other Specified, Unspecified, due to….

Clinical Aspects of Eating Disorders

• Common Characteristics of Eating Disorders

  • Intense Fear of Weight Gain: A pathological fear of becoming “overweight” or “fat” or “big.”

  • Pursuit of Thinness: A relentless and sometimes deadly pursuit of thinness.

  • Disturbed Eating Patterns: Exhibiting abnormal eating behaviors.

Major Eating Disorders

1. Anorexia Nervosa

• DSM-5 Criteria:

  • A. Food restriction leading to significantly low weight according to demographic/developmental age (For adults, BMI < 18).

  • B. Intense fear of gaining weight; intentional prevention of healthy weight gain.

  • C. Disturbance in perception of body weight/shape; impact on self-evaluation; inability to recognize the seriousness of low body weight.

• Types:

  • Restricting Type: Characterized by dieting, fasting, or excessive exercise over a period of 3+ months.

  • Binge-Eating/Purging Type: Characterized by binge eating or purging behaviors over a period of 3+ months.

2. Bulimia Nervosa

• DSM-5 Criteria:

  • A. Recurrent episodes of binge eating.

  • B. Recurrent compensatory behaviors (purging or non-purging, such as excessive exercise or fasting).

  • C. Binge eating and purging occur at least 1 time per week for 3+ months.

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

  • E. Does not occur exclusively during an episode of anorexia nervosa.

• Typical Characteristics:

  • Usually of normal weight to slightly overweight.

  • Increased likelihood of bingeing with access to “forbidden foods.”

3. Binge Eating Disorder (BED)

• DSM-5 Criteria:

  • Frequent Episodes: At least 1 time per week for 3 months.

  • Consequences: May result in becoming overweight or obese.

  • Absence of Compensatory Behaviors: No purging or similar behaviors.

  • Binge Episode Characteristics: Must have 3 or more of the following:

  1. Eating rapidly.

  2. Eating until feeling uncomfortably full.

  3. Eating a lot when not hungry.

  4. Eating alone due to embarrassment.

  5. Feeling disgusted, depressed, or guilty afterward.

Comparative Analysis of Eating Disorders

Table 9.2: Comparing Anorexia Nervosa, Bulimia Nervosa, and Binge-Eating Disorder

• Symptom Analysis

  • Body Weight:

  • Anorexia Nervosa: Markedly low.

  • Bulimia Nervosa: Markedly low.

  • Binge-Eating Disorder: Typically overweight or obese.

  • Fear of Weight Gain:

  • Present in Anorexia and Bulimia.

  • Not typically present in Binge-Eating Disorder.

  • Body Image Distortion:

  • Present in Anorexia and Bulimia.

  • Overconcerned with body and weight in Binge-Eating Disorder, but may not have distorted perception.

  • Binge Eating:

  • Absent in Anorexia Nervosa (restricting type).

  • Present in Bulimia Nervosa and Binge Eating Disorder.

  • Purging:

  • Absent in Anorexia (restricting type).

  • Present in Bulimia Nervosa.

  • Absent in Binge Eating Disorder.

Age of Onset and Gender Differences

• Age Range:

  • Anorexia Nervosa: 16-20 years.

  • Bulimia Nervosa: 21-24 years.

  • Binge Eating Disorder: 30-50 years.

• Gender Ratios: (3:1 female to male)

  • Women have higher rates than men.

  • Potential gender bias in diagnosis.

• Lifetime Prevalence Rates:

  • Anorexia: W: 0.9%, M: 0.3% (generally poor prognosis).

  • Bulimia: W: 1.5%, M: 0.5% (better prognosis than AN).

  • BED: W: 3.5%, M: 2.0% (high remission rates).

Medical Complications of Eating Disorders

• Anorexia: The body begins to consume itself for energy; fat is burned first, followed by muscle, leading to organ damage.

• Bulimia: Potential complications include:

  • Electrolyte imbalances.

  • Hypokalemia (low potassium).

  • Damage to heart, hands, throat, and teeth due to purging behaviors.

Common Comorbidities

• Eating Disorders and Other Disorders:

  • Clinical depression (~50-70% of cases).

  • Neuroticism.

  • Perfectionism.

  • Obsessive-Compulsive Disorder (associated with AN & BN).

  • Impulsivity (common in binge eating).

  • Various personality disorders (~60% of cases), including:

  • Obsessive-Compulsive Personality Disorder (predominantly associated with AN).

  • Borderline Personality Disorder (often associated with the binge/purge subtype).

Cultural Considerations in Eating Disorders

• Eating disorders are increasingly recognized globally, with cultural expressions varying, e.g.:

  • "Fat" phobia arising from Western cultures.

  • Cultural ideals around body image affecting prevalence.

  • Discussion over whether eating disorders are primarily a “Rich White Girl problem.”

Diagnostic Crossover in Eating Disorders

• Common Transitions Between Eating Disorders:

  • High bidirectional transitions between different subtypes of anorexia.

  • Transition from anorexia (binge/purge type) to bulimia once above the underweight threshold is common.

  • Less common for individuals to shift from bulimia to anorexia, especially restrictive anorexia.

  • Individuals diagnosed with binge eating disorder may fluctuate in the use of compensatory behaviors.

  • Rare transitions between BED and anorexia.

Risk Factors for Eating Disorders

Biological Factors

• Hereditary Tendency: Genes may play a role, potentially as substantial as for bipolar disorder and schizophrenia.

• Set-point Theory: Suggests a biological equilibrium that may lead to binge eating behaviors as a compensatory mechanism in response to changes.

• Serotonin: Linked to mood and appetite regulation; its dysfunction may contribute to impulsivity and eating disorders.

Sociocultural Factors

• Media Influence: Extreme body ideals propagated by media, particularly in Western cultures.

• Cross-Cultural Differences: Variations in perceptions of beauty can influence the development of eating disorders.

Family Influences

• Parental Attitudes: Family relationship dynamics and attitudes towards body image and eating may impact individual vulnerability.

Individual Risk Factors

• Demographics: Age (adolescent to young adult), gender (including LGBTQ+ identities), and sexual orientation.

• Psychological Traits: Perfectionism, impulsivity, negative body image, and past trauma (e.g., childhood sexual abuse).

Treatment of Eating Disorders

1. Treatment of Anorexia Nervosa

• Common Treatments Include:

  • Emergency procedures aimed at restoring weight.

  • Antidepressants or other medications.

  • Family-based therapy approaches.

  • Cognitive-Behavioral Therapy (CBT) and its enhanced version (CBT-E).

2. Treatment of Bulimia Nervosa and Binge Eating Disorder

• Common Treatments Include:

  • Antidepressants or other medications.

  • Cognitive-Behavioral Therapy (CBT-E).

  • Interpersonal Therapy (IPT).