Eating Disorders Flashcards
ICD-10 for Anorexia Nervosa
All of:
a) Low body weight, BMI 15% less of what it should be(in adults <17.5 kg/m²)
b) Self-induced weight loss(poor caloric intake, vomiting, overexercise, etc)
c) Overvalued idea: dreading fatness, self-perception of being too fat, low target W
d) Endocrine disturbance(amenorrhoea, loss of libido, impotency;raised cortisol, growth hormone;low T3 etc)
*Prepubertal: failure to make expected weight gains, delayed pubertal events.
ICD-10 for Bulimia Nervosa
All of:
- Binge eating
- Strong cravings for food.
- Methods to counteract weight gain(vomiting, laxatives, fasting, exercise)
- Overvalued idea: dread of fatness, self-perception of being too fat, low target weight)
MEDICAL COMPLICATIONS RELATED TO STARVATION:
a) Complications, features
b) Lab tests
a) - lanugo: fine, downy hair
- cardiomyopathy, bradycardia, hypotension, arrhytymia, heart failure
- proximal myopathy, muscle-wasting
- amenorrhoea, infertility, reproductive system atrophy
- emaciation
- osteoporosis, fractures
- seizures, impaired conc., depression
- constipation, abdominal pain
- cold intolerance, lethargy
b) - hypercholesterolaemia, hypercarotenemia
- hypoglycemia, impaired glucose tolerance
- low T3
- reduced FSH and LH, oestrogen and testosterone
- raised growth hormone, cortisol
- raised urea
- abn. LFT
- normocytic anemia, leucopenia
MEDICAL COMPLICATIONS RELATED TO VOMITING:
a) Clinical features
b) Lab tests
a) - Russell’s sign
- Oesophageal tears, gastric rupture
- Enlarged parotids
- Dental cavities, erosion of enamel
- chronic abdominal problems with laxative use: slowed transit time, obstruction, perforation
b) - hypokalaemic, hypochloraemic alkalosis
- hyponatraemia
- hypomagnesaemia
- raised serum amylase
INVESTIGATIONS
- ECG
- FBC, U&E’s, LFT, serum glucose and lipids
- *not routinely: cortisol, FSH, LH, insulin, growth hormone
- Consider bone density(DXA) scan
DDx for Weight loss:
- Anorexia nervosa
- may retain appetite until later stages of disease
- retain interest in food-related subjects ie low-calorie recipes - Bulimia nervosa
- Depression
- associated loss of appetite
- can be biological consequence of starvation - OCD
- increased incidence in anorexia nervosa
- Dx when obsession/compulsion unrelated to food/body shape - Psychotic disorder
- Alcohol/substance abuse
- Medical causes
- Dementia
EPIDEMIOLOGY
- Females(10x more common)
- 14-25y
- Anorexia: 0.3% young women; higher prevalence in ballet dancers, gymnasts, athletes
- Bulimia: 1% young women; equal socioeconomic class distribution.
AETIOLOGY(ANOREXIA NERVOSA):
a) Genetic
b) Environmental/psychological
a) - 58-76% responsible
- Dysfn. in serotonin metabolism
- Certain personality traits: inhibition, perfectionism, obsessionality, harm-avoidance.
b) - Social construct of ‘ideal body image’
- Over-protectiveness, enmeshment, conflict avoidance, rigidity in families
AETIOLOGY(BULIMIA NERVOSA)l
a) Genetic
b) Environmental/psychological
a) - 54-83% responsible
- FHx of depression, substance misuse
b) - Past exposure to dieting behaviour, eg in history of childhood obesity, parental obesity, early menarche
- Conflictual family relationships
- Associated with depression, susbstance abuse, personality disorders
- Perfectionism
MANAGEMENT(ANOREXIA NERVOSA)
- Psychoeducation, motivational interviewing
- Nutrition management and weight restoration
- caution refeeding syndrome - IPT
- Family therapy
- CBT
- Community outreach
- May require detention under Mental Health Act
- Monitor weight, treat med complications
- SSRIs for comorbid depression and OCD
POOR PROGNOSTIC FACTORS(ANOREXIA NERVOSA)
- Late age of onset
- Family difficulties
- Poor social adjustment
- Long duration of illness
- V. low weight
- Associated binge-purge symptoms
- Personality difficulties
REFEEDING SYNDROME
- Electrolyte abn.
- Clinical features
- a) Hypophosphotaemia
b) Hypokalaemia
c) Hypomagnesaemia
d) Hyponatraemia
e) Metabolic acidosis
f) Thiamine deficiency - a) Muscle weakness
b) Seizures
c) Peripheral oedema
d) Cardiac dysrhythmias
e) Hypotension
f) Delirium
MANAGEMENT(BULIMIA NERVOSA)
- Referral to specialist care in all cases.
1. Psychological: Psychoeducation, CBT(first-line)(mild), IPT(more severe)
2. Manage electrolyte disturbances
3. High-dose SSRIs for binge-purge cycles
4. Manage comorbid abuse and depression
5. Does not usually req. in-patient treatment.
PROGNOSIS(ANOREXIA NERVOSA)
- 15% lifetime mortality
- 50% from complications of starvation
- 1/3 from suicide - Around 20% full recovery
- 25% develop bulimia nervosa
- 20% remain severely unwell
- Remainder follow relapsing-remitting course
PROGNOSIS(BULIMIA NERVOSA)
- 50-70% full/partial recovery after 5y.
- Strong association with depression and substance abuse
- Bulimia nervosa itself not associated with increased mortality
- Poor prognostic factors:
- severe binge-purge
- comorbid depression
- low body weight
