6. Eating disorders

Question 1

Describe the pathophysiology of eating disorders (3)

Answer 1

• Eating disorders arise from the interplay between genetic, psychological, and social factors.
• The exact pathophysiology is unknown.

Question 2

Name: Conditions associated with weight loss (Figure)

Answer 2

Question 3

Describe HX of eating disorder (6)

Answer 3

• A thorough history is essential to determine if a psychiatric Dx weight loss
  
  • Psychosocial stressors are particularly important to elicit.
• Weight loss can be part of a wide range of illness including the major psychiatry illness such as major depression or schizophrenia, which are important to rule out. In these causes, the weight loss is a symptom and not the key feature.
• In eating disorders, there is a disturbed eating pattern that can lead to significant weight loss.
  
  • It is important to elicit the details around the disordered eating to see if the key features of Anorexia Nervosa or Bulimia Nervosa are present.
    
    • Eating in secrecy (Bulimia Nervosa), calorie counting
  • Pica and avoidant/restrictive food intake disorder are typically diagnoses of childhood.
  • Anorexia Nervosa and Bulimia Nervosa typically start in adolescent but onset can be at any age.
• There is high comorbidity of other psychiatric illnesses, so it is important to do a thorough psychiatric screen.
• Eating disorders have an associated increased risk of suicide, so it is essential to screen for suicidal ideation.
• A thorough ROS screening should be done to determine any medical problems such as amenorrhea, constipation, etc.

Question 4

Describe physical exam of eating disorder (3)

Answer 4

• Important to document the BMI:
  
  • BMI may determine Anorexia Nervosa versus Bulimia Nervosa.
  • To assess current severity and follow the course of the eating disorder
• Signs of purging
• Signs of starvation

Question 5

Name Signs of purging (2)

Answer 5

• Teeth changes: enamel erosion, chipped/ragged, dental caries
• Salivary gland hypertrophy, especially parotid

Question 6

Name Signs of starvation (3)

Answer 6

• Lanugo hair (fine downy)
• Emaciation
• Peripheral edema

Question 7

Describe investigations: Eating disorders (5)

Answer 7

• There are no investigations to diagnose an eating disorder.
• Investigations are important to:
  
  • rule out any medical illnesses causing the weight loss; and
  • determine any physiologic comorbidities induced by the disordered eating.
• Basic investigations:
  
  • CBC
  • basic and extended electrolytes
  • LFTs
  • TSH
  • ECG
• Dx of an eating disorder is based on the history and presenting features.
• It is important to rule out causes of weight loss from medical illness, medications, or substance use.

Question 8

Describe Dx of eating disorders (Figure)

Answer 8

Question 9

Name key features of Anorexia Nervosa (5)

Answer 9

• Persistent restriction of energy intake relative to requirements, leading to significantly low body weight, less than that minimally expected (for age, gender, and developmental trajectory)
• Intense fear of gaining weight or of becoming fat, or persistent behavior that interferes with weight gain
• Distorted self-perception (thin girl perceiving herself as a fat person in mirror), overvalued significance of body weight and shape on self-evaluation, or lack of insight into significance of low body weight
• Can Specify Restricting Type or Binge-Eating/Purging Type
  
  • Restricted Type - in past 3 months no binge eating or purging behavior
  • Binge-Eating Purging Type - in past 3 months has had recurrent binge eating or purging behavior
• Mild - BMI > 17, moderate - BMI 16–16.9, severe - BMI 15–15.9, and extreme - BMI < 15

Question 10

Name key features of Bulimia Nervosa (4)

Answer 10

• Recurrent episodes of binge eating, consuming more than a normal person and which is accompanied by a sense of lack of control
• Recurrent inappropriate compensatory behaviors to prevent weight gain (e.g., vomiting, laxatives, excessive exercise, restricting intake)
• Self-evaluation that is unduly influenced by body shape and weight
• Episodes inappropriate compensatory behaviors occur on average- 1–3 × a week for mild, 4–7 × a week for moderate, 8–13 × a week for severe, and 14 or more × a week for extreme severity.

Question 11

Describe management: Eating disorder (5)

Answer 11

• Outpatient psychotherapy is the cornerstone of clinical care for eating disorders.
  
  • CBT treatment of choice for eating disorders
• Medications, such as SSRIs and antipsychotics, play a limited role in the clinical treatment of Anorexia Nervosa due to limited evidence.
• Some evidence of SSRIs in Bulimia Nervosa to decrease binge and purge episodes, as well as relapse
  
  • Combo of SSIRs + psychotherapy best outcomes
• Management of complications, such as osteoporosis, may be warranted.
• Hospitalization or day-hospital treatments may be required to restore weight and to address medical complications.