Eating Disorders

Question 1

What is required for a diagnosis of anorexia nervosa?

Answer 1

1. Weight loss, or in children a lack of weight gain, leading to a body weight of at least 15% below the normal or expected weight for age and height.
2. The weight loss is self-induced by avoidance of “fattening foods”.
3. A self-perception of being too fat, with an intrusive dread of fatness, which leads to a self-imposed low weight threshold.
4. A widespread endocrine disorder involving the hypothalamic-pituitary- gonadal axis, manifest in the female as amenorrhoea, and in the male as a loss of sexual interest and potency (an apparent exception is the persistence of vaginal bleeds in anorexic women who are on replacement hormonal therapy, most commonly taken as a contraceptive pill).

Question 2

What occurs in anorexia nervosa if the onset is pre-pubertal?

Answer 2

The sequence of pubertal events is delayed or even arrested (growth ceases; in girls the breasts do not develop and there is a primary amenorrhoea; in boys the genitals remain juvenile). With
recovery, puberty is often completed normally, but the menarche is late.

Question 3

What is required for a diagnosis of Bulimia Nervosa?

Answer 3

1. Recurrent episodes of overeating (at least two times per week over a period of three months) in which large amounts of food are consumed in short periods of time.
2. Persistent preoccupation with eating and a strong desire or a sense of compulsion to eat (craving).
3. The patient attempts to counteract the fattening effects of food by one or more of the following:
   (1) self-induced vomiting;
   (2) self-induced purging;
   (3) alternating periods of starvation; use of drugs such as appetite suppressants, thyroid preparations or diuretics. (When bulimia occurs in diabetic patients they may choose to neglect their insulin treatment)
4. A self-perception of being too fat, with an intrusive dread of fatness
   (usually leading to underweight).

Question 4

What is an episode of binge eating characterised by?

Answer 4

Eating, in a discrete period of time (e.g. within any 2-hour period), an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances.
A sense of lack of control over eating during the episode (e.g. a feeling that one cannot stop eating or control what or how much one is eating).

Question 5

What are binge eating episodes associated with in a BE disorder (BED)?

Answer 5

3 or more of:
eating much more rapidly than normal
eating until feeling uncomfortably full
eating large amounts of food when not feeling physically hungry
eating alone because of feeling embarrassed by how much one is eating
feeling disgusted with oneself, depressed or very guilty afterward

Question 6

What is the sex ratio in eating disorders?

Answer 6

1:2 M:F

Question 7

When does AN usually present?

Answer 7

18 (but pubertal onset typical of 7-15yo)

Question 8

When does BN usually present?

Answer 8

20yo (more common in younger people)

Question 9

What are the behavioural features in the evolution of AN?

Answer 9

High Risk: Feeding problems, decreased BMI, social difficulties
Prodromal: Coping, avoidance, perfectionism
Full syndrome: Increased control of eating, weight control behaviours
Severe Enduring: Social isolation, impaired physica and mental QOL

Question 10

What are the psychosocial features in the evolution of AN?

Answer 10

High Risk: Decreased reward and increased threat, sensitivity, social cognition problems, cognitive rigidity
Prodromal: Compulsivity, anxiety
Full syndrome: Cognitive control over drives, emotional avoidance, ability to delay reward
Severe enduring: Habits not goal directed behaviours, threat sensitivity, decreased social cognition

Question 11

What are the behavioural features in the evolution of BED/BN?

Answer 11

High Risk: Robust feeding, increased BMI
Prodromal: Poor problem solving, increased attention to food
Full syndrome: Loss of control of eating
Severe enduring: Impaired physical and mental QOL

Question 12

What are the psychosocial features in the evolution of BED/BN?

Answer 12

High Risk: Increased reward sensitivity, decreased response inhibition to food
Prodromal: Emotional suppression
Full syndrome: Decreased cognitive control over drives, decreased ability to delay reward
Severe enduring: Habits not goal directed behaviour, addiction proneness

Question 13

What is the genetic link in eating disorders?

Answer 13

50-75% heritability, 10x risk in affected families

Question 14

What is the snowball metaphor for severe enduring eating disorders?

Answer 14

Over time neuroprogression causes a snowball effect: symptoms and complexity increase

Question 15

What is the mortality for AN?

Answer 15

5.86 SMR

1 in 5 AN deaths by suicide

Question 16

What are some comorbidities related to ED’s?

Answer 16

Depression
OCD
Substance misuse
DM

Question 17

What are the effects of starvation on the brain?

Answer 17

Loss of grey and white matter
Increased compulsive behaviour
Enhanced response to hedonic and nutrostat  signals
Reduced social skills
Focus on food
Poor concentration and decision making
New learning stunted

Question 18

What is refeeding syndrome?

Answer 18

Caused by depletion of already inadequate stores of nutrients e.g. magnesium, potassium, phosphate which are quickly used up as body starts to repair itself.

Question 19

How is refeeding syndrome prevented?

Answer 19

Prevent by frequent blood monitoring and slow pace of initial refeeding.

Question 20

What are the metabolic medical complications of refeeding syndrome?

Answer 20

Hypothermia
Dehydration
Electrolyte disturbance (low potassium,  magnesium, calcium, phosphate)
Hypoglycaemia
Raised LFTs

Question 21

What is the risk assessment in refeeding syndrome related to BMI?

Answer 21

Low-moderate: BMI 17.5-16
Moderate: 16-15
High: 14.9-13
Very high: <13

Question 22

What is included in the risk assessment of refeeding syndrome other than BMI?

Answer 22

Rate of weight loss
Blood results
Circulation
Muscle strength
Temperature
ECG abnormalities