Session 06 - Eating Disorders Flashcards
What is an eating disorder?
A group of conditions characterised by a disorganised pattern of food consumption, which causes emotional and physical distress.
What are the most common eating disorders?
- anorexia nervosa
- bulimia nervosa
What are the biological causes of eating disorders?
Genetics: twin studies have shown eating disorders share a large genetic component.
5-HT: altered brain serotonin contributes to disregulation of appetite, mood and impulsivity.
What are the psychological causes of eating disorders?
Personality: higher association with anxious, obsessive-compulsive and depressive traits.
Self-esteem: higher incidence in people with low self-esteem and altered body image.
What are the social causes of eating disorders?
Childhood: sexual and emotional abuse, overprotective environment, troubled family.
Media: excessive exposure to media adverts and models encouraging excessive dieting.
What are the metabolic symptoms of eating disorders?
Low T3: bradycardia, hypotension and hypothermia.
Hypercholesterolaemia and poor glucose tolerance.
Raised cortisol and growth hormone.
Hypokalaemia.
Low FSH, LH, oestrogen and testosterone.
What are the tissue symptoms of eating disorders?
Bone: osteoporosis.
Muscle: breakdown and weakness.
Enlarged salivary glands.
Lanugo hair: soft, unpigmented furry hair.
Russel’s sign: hand callouses (self-vomiting).
What is anorexia nervosa?
A disorder characterised by restrictive eating, which is due to a morbid fear of fatness.
Patients lose weight either by dieting, purging (vomiting), laxative/diuretic abuse.
Diagnosis of anorexia nervosa.
3 key features:
- low body weight (<85%)
- distorted body image
- morbid fear of fatness
Other symptoms:
- amenorrhoea
- loss of libido
Indications of NG feeding in anorexia nervosa.
Acute NG feeding tube if:
- BMI <13
- bradycardic
- K+ <3mmol/L
- clearly dehydrated
Chronic management of anorexia nervosa.
Referral for specialist care:
Adults - first line is eating disorder focussed CBT or specialist supportive clinical management (SSCM).
Children - first line is anorexia focused family therapy; second line is CBT.
Prognosis of anorexia nervosa.
40% recover.
10% mortality.
What is bulimia nervosa?
A disorder characterised by episodes of binge eating followed by intentional purgative behaviours in order to lose weight.
This can include intentional vomiting, excessive exercise and laxative / diuretic abuse.
Diagnosis of bulimia nervosa.
5 key features:
- preoccupation with body shape and weight
- recurrent binge eating
- inappropriate compensatory behaviours to stop weight gain
- occur once weekly for at least 3 months
- episodes not occurring during episode of anorexia nervosa
Note weight is typically normal.
Acute management of bulimia nervosa.
NG feeding tube if:
- BMI <13
- bradycardic
- K+ <3mmol/L
- clearly dehydrated