ED: Anorexia Nervosa

Question 1

Define anorexia nervosa.

Answer 1

ED characterised by deliberate weight loss resulting in weight below 15% of expected or BMI <17.5, with secondary endocrine + metabolic disturbances.

Question 2

What 3 elements are the diagnosis of anorexia nervosa based on?

Answer 2

1. RESTRICTION of energy INTAKE relative to requirements leading to significantly low weight in context of age, sex, developmental trajectory, + physical health.
2. Intense FEAR of gaining weight or becoming fat, even though underweight.
3. DISTURBANCE in way in which one’s BODY weight/ shape is EXPERIENCED, undue influence of weight/ shape on self-evaluation, or denial of seriousness of current low body weight.

Question 3

Give 6 risk factors for anorexia nervosa.

Answer 3

Female
Age
Western society: Sociocultural view of thin is desirable
FH ED, depression, substance misuse
Premorbid experiences
Personality

Question 4

Give 5 premorbid experiences that are risk factors for anorexia

Answer 4

Sexual abuse
Dieting behaviour within family
Occupational/ recreational pressure to be slim- models, dancers, gymnasts
Onset of puberty
Criticism/ perceived criticism about weight/ eating

Question 5

Give 6 personal characteristics that are RFs for anorexia

Answer 5

Perfectionism
Low self-esteem
Obsessive traits
Difficulty resolving conflict
Anxiety
EUPD

Question 6

Summarise the epidemiology of anorexia nervosa.

Answer 6

90% Female

Female lifetime prevalence 2-4%

Peak 15-19y

Higher in high SES

Question 7

What are 2 behaviours of anorexia nervosa?

Answer 7

Weight loss induced by vomiting, excessive exercise, appetite suppression, diuretics + laxatives.

Morbid fear of fatness, body image distortion, loss of libido, fatigue, amenhorrea, obsessional thoughts + rituals.

Question 8

Give 7 physiological disturbances that may be seen in anorexic patients

Answer 8

Hypokalaemia
Low FSH, LH, oestrogens + testosterone
High cortisol + growth hormone
Impaired glucose tolerance
Hypercholesterolaemia
Hypercarotinaemia
Low T3

Question 9

Give 8 features of am anorexia patient appear on examination?

Answer 9

Dehydration

Proximal myopathy

Cold extremities

Bradycardia

Hypotension

Fine lanugo hair

Peripheral odema

Parotid enlargement + erosion of tooth enamel (vomiting)

Low mood likely

Question 10

What 6 physical symptoms may be experienced by an anorexic patient?

Answer 10

Amenorrhoea
GI Sx: constipation, fullness, dysphagia + abdo pain
Fatigue
Dizziness/ fainting
Cold intolerance
Delay in secondar sexual characteristics

Question 11

What should you examine in anorexia nervosa?

Answer 11

Height, weight + BMI

Basic obs + check for postural hypotension

Squat test: ask to squat + stand without using hands

Question 12

What investigations are required in anorexia nervosa?

Answer 12

FBC: ?anaemia
U+Es: disturbances caused by purging
LFTs: transaminitis
TFTs: ddx Hyperthyroidism
Hormones: monitor
Glucose, amylase, lipids, toxicology
ECG: bradycardia, QT prolongation
DEXA: very high risk of osteoporosis

Question 13

What screening tool can be used to manage anorexia nervosa?

Answer 13

MARSIPAN checklist for really sick patients with anorexia nervosa
Assess severity, refeeding + managing

Question 14

What are 8 indications for admission in a patient with AN?

Answer 14

Exceedingly low weight
Precipitous loss of weight
Significant…
Bradycardia <40 bpm/ prolonged QT
Hypotension
Hypothermia
Electrolyte abnormalities
Hypoglycaemia
Psych instability inc. suicidality

Question 15

What is the management for anorexia nervosa?

Answer 15

Correct medical complications (hydration, electrolytes)

Psychiatric admission + feeding (either controlled or NG tube if will not take food)

Negotiate dietary aims

CBT, family therapy, SSRIs may help

Dietician involvement

Question 16

What psychological therapies can be used in AN?

Answer 16

Individual eating-disorder-focused CBT (CBT-ED) (40, >once a week)
Maudsley Anorexia Nervosa Tx for Adults (MANTRA) (20- weekly for first 10)
Specialist supportive clinical Mx (SSCM) (20 weekly)

Question 17

What psychological therapies are recommended for children with AN?

Answer 17

Anorexia Focused Family Therapy (20)
2nd: CBT-ED

Question 18

What is re-feeding syndrome?

Answer 18

Potentially fatal shifts in fluids + electrolytes that occur in a malnourished patient on refeeding following a period of starvation
Hypophosphataemia
Hypomagnesaemia
Hypokalaemia

Question 19

Describe the pathophysiology of re-feeding syndrome

Answer 19

Chronic malnutrition leads to protein catabolism with total body phosphate depletion despite normal serum phosphate

Intro of carbohydrates leads to anabolic state which unmasks total body phosphate depletion + leads to precipitous drop in serum phosphate
Glucose stimulates insulin release = massive uptake of phosphate, K+ and Mg2+ into cells

Question 20

What are the complications of re-feeding syndrome?

Answer 20

Hypophosphatemia: CHF, arrhythmias, confusion, seizures
Hypomagnesemia: arrhythmias, tachycardia, diarrhoea, seizures, hypocalcaemia
Hypokalaemia: ileus, cardiac arrest, arrhythmias, paralysis, respiratory depression
Fluid excess (i.e. rapid weight gains, changes in serum sodium, increased BP + HR)
Hyperglycaemia

Question 21

What are 6 complications associated with anorexia nervosa?

Answer 21

Osteoporosis
Infertility
Arrhythmias
Electrolyte disturbances + dehydration
Infections- low WCC
Renal failure: chronic volume depletion

Pancreatitis
Hepatitis
Seizures
Peripheral neuropathies
Suicide

Question 22

What is the prognosis of anorexia nervosa?

Answer 22

46% recover completely
34% improve partially
20% develop chronic ED

Mortality 5x higher than gen pop.

Poor coutcome if older onset age, long duration of illness, low weight at presentation + poor childhood social adjustment.