8. Eating Disorders

Question 1

DSM-5 diagnostic criteria for Anorexia Nervosa

Answer 1

• Restriction of input relative to exact requirements leading to significantly low body weight
• Marked and excessive fear of putting on weight/becoming fat: repetitive behaviours to prevent weight gain
• Distortions in self-perception of body weight/shape associated with lack of recognition of serious consequences of current low body weight

Question 2

Subtypes of Anorexia Nervosa

Answer 2

Restricting: weight loss over the last 3 months achieved mainly by means of dieting, fasting or excessive exercise

Binge-eating/Purging: recurrent episodes of binge-eating or purging behaviours over the last 3 months

Question 3

Management for AN

Answer 3

Pharmaco (no drugs proven effective):
- Fluoxetine (improvement in mood)
- Mirtazapine (can promote weight gain)

Non-pharmo:
- CBT
- Interpersonal psychotherapy
- AN focused family therapy

Question 4

Reasonable target weight gain

Answer 4

Increment of 0.5-1kg per week

Question 5

Poor prognostic factors in Anorexia Nervosa

Answer 5

• Relatively late age of onset
• Presence of severe vomiting and weight loss
• Dysfunctional family
• Extreme treatment avoidance
• Longer duration of illness
• Personality disorder
• Male gender
• Very low BMI

Question 6

Favourable prognostic factors in Anorexia Nervosa

Answer 6

• Early onset
• Absence of severe weight loss and serious medical conditions
• Supportive family
• Good motivation to change

Question 7

Necessary investigations for AN patients

Answer 7

FBC, LFT, RP, electrolytes, hormone profiles, fasting venous glucose, ECG, EEG
Cognitive assessment and further risk assessment

Question 8

Refeeding syndrome symptoms

Answer 8

Dependent edema, aches and pains
Electrolyte deficiencies
Cardiac decompensation (CHF)

Question 9

DSM-5 diagnostic criteria for Bulimia Nervosa

Answer 9

• Recurrent episodes of binge eating: lack of control and eat till excessively full
• Repetitive compensatory behaviour: self-induced vomiting, usage of laxatives
• Duration: at least once a week for 3 months
• Self-esteem

Question 10

What is Russell’s sign?

Answer 10

Abrasions over dorsal part of the hand (interphalangeal joints) because fingers are used to induce vomiting
- more commonly seen in BN

Question 11

Management of Bulimia nervosa

Answer 11

Pharmaco:
- Antidepressant: Fluoxetine (improvement in mood)
- Mood stabilisers

Non-pharmo:
- CBT
- Interpersonal psychotherapy

Question 12

Note that in AN the BMI is very very low while in BN the BMI can be normal or high

Answer 12

-

Question 13

Indications to hospitalisation for anorexia nervosa

Answer 13

1. BMI < 15kg/m^2
2. Bradycardia < 40bpm
3. Failure of outpatient treatment
4. High self-harm/suicide risk

Question 14

Reason for parotid gland swelling in Bulimia nervosa

Answer 14

Frequent self-induced vomiting in BN leads to reflux of gastric acid and causes inflammation in the parotid gland

Question 15

Laxative use can cause

Answer 15

metabolic acidosis

Question 16

Repeated vomiting can cause

Answer 16

Hypokalemic, hypochloremic metabolic alkalosis

Question 17

Objective signs to establish diagnosis of AN

Answer 17

Low BMI
Amenorrhea

Question 18

Physical findings in patient with AN

Answer 18

Low weight, bradycardia, hypotension, amenorrhea, breast atrophy, muscle weakness, peripheral neuropathy, increase in body hair (lanugo hair), dry skin, alopecia

Question 19

Electrolyte abnormalities in Anorexia nervosa

Answer 19

• Low Ca2+
• Low Mg2+
• Low PO4
• Low Na+
• Low K+
• High amylase
• Low albumin
• Low glucose
• Low insulin
• High lipid
• Metab acidosis (diarrhoea)
• Metab alkalosis (vomiting)

Question 20

Hormonal changes in anorexia nervosa

Answer 20

• Low oestrogen
• Low testosterone
• Low T4/T3
• Low FSH/LH
• High cortisol
• High growth hormone

Question 21

What is considered purging?

Answer 21

Self induced vomiting
Excessive use of laxatives
Excessive use of diuretic
Excessive use of enema

(purging: evacuation of GI or urinary system hence excessive exercise is not considered purging)

Question 22

Factors influencing prognosis for bulimia nervosa

Answer 22

● Good
- Ability to engage in treatment
- Motivation for change
● Bad
- Childhood obesity
- Low self esteem
- Associated personality disorder
- Substance abuse

Question 23

What happens if lots of nutritional supplement is given to an ED patient

Answer 23

Refeeding syndrome

Question 24

What happens during refeeding syndrome?

Answer 24

Worsens electrolyte deficiencies:
- Hypophosphotemia
- Hypokalaemia
- Hypomagnesemia
Seizures
Congestive heart failure
Peripheral oedema
Respiratory insufficiency
Aches and pains
Rhabdomyolysis
Haemolysis

*During early stages of refeeding, a resting heart rate of >70bpm may suggest heart failure and refeeding syndrome

Question 25

Severity markers based on BMI

Answer 25

Mild: >17
Moderate: 16-16.9
Severe: 15-15.9
Extreme: <15

Question 26

Signs of repeated self-induced vomiting

Answer 26

• Russell’s sign
• Parotid gland enlargement
• Erosion of tooth enamel
• Dental caries

Question 27

Hallmark manifestation of refeeding syndrome

Answer 27

Hypophosphatemia

Question 28

Which antiD should be avoided for patients with eating disorder and why?

Answer 28

Bupropion
- higher incidence of seizures
- weight loss

Question 29

Binge Eating Disorder

Answer 29

Characterised primarily by episodes of recurrent binge eating episodes without compensatory purging behaviours. It was a/w 3 or more of the following:

• Eating rapidly until uncomfortably full
• Eating large amounts despite lack of hunger
• Eating in solitude to avoid embarrassment
• Feelings of disgust or guilt following the episode