Anorexia Nervosa

Presentation

  • When first brought to medical attention?
  • Why?

History

  • Fat in past
  • Dieted or controlled calories
  • Exercise
  • Previous investigations for
    • diarrhoea
    • metabolic problems
    • amenorrhoea
  • Body image / fear of fatness
  • Bulimic episodes
  • Menstrual History

PMH

  • diabetes
  • thyroid disease

FHx

  • ↑ incidence of eating disorders in family members

Personal

  • disturbed family relationships
  • avoidance of maturity
    • inc. sexual relationships
  • denial of family problems
  • parental discord
    • divorce
    • separation

DHx

  • laxatives
  • diuretics
  • Smoking
  • Alcohol

ROS

Examination

Mental State Exam

  • Behaviour
    • normal
  • Speech 
    • normal
  • Mood
    • anxious
    • depressed
    • unconcerned about health
  • Thought
    • abnormal body image
    • may be suicidal
  • Perception
  • Orientation
  • Attention
  • Memory
  • Insight
    • lacking re health

Physical

  • General
    • thin
    • cold peripheries
    • lanugo hair
    • BMI
    • exclude hyperthyroidism, etc.

Differential Diganosis

Diagnosis

  • Severe weight loss
    • Body weight 15% or more below expected or BMI <17.5
    • Prepubertal patients fail to show expected weight gain
    • Weight loss self-induced by avoidance of fattening foods + one or more from
      • self-induced vomiting
      • purging
      • excessive exercise
      • use of appetite suppressants
      • diuretics
  • Body image distortion and disturbance
    • dread of fatness
    • self-imposed low weight threshold
  • Amenorrhoea, loss of sexual interest, potency
  • Delay or arrest of puberty

Investigations

  • social investigations of family relationships
  • Glucose
  • Thyroid function tests
  • U&E
    • K+ ↓ with purgatives / diuretics
  • ↓ Protein
  • ↓ FSH / LH
  • ↑ ACTH

Epidemiology

Incidence 5.1 per 100,00 per year

Prevalence

  • Community 370 / 100,000 young females
  • Primary care 160 /100,000 y.f.
  •  Mental Health Care 87 / 100,00 y.f.

Aetiology

  • ?Genetic component
  • ?Obstetric disaster in preceding pregnancy
  • More affluent social class
  • Type school
    • private
    • very high achieving
  • Occupations
    • dance, esp ballet
    • modelling
    • acting
    • horse-racing
    • wrestling
  • Western culture
    • High valuation of thinness
    • ambiguous position of Western women in society

Treatment

Stepped-care approach

Detection

  • in a young woman between puberty and mid twenties

    • primary or secondary amenorrhoea

    • growth failure

    • weight loss

    • unexplained vomiting diarrhoea

or exclusion of other wasting diseases

Self Help

  • Anorexia Nervosa (R.L. Palmer)
  • Anorexia Nervosa  - let me be (A.H. Crisp)

Treatment in primary care

  1. Monitoring of physical and mental state
  2. encouragement to gain weight
  3. support of the family
  4. may require antidepressants
  • Initial screening
    • muscle power
      • standing from squatting
      • sitting from lying flat
    • standing and lying BP
      • postural hypotension may be symptomatic of cardiac involvement in malnutrition or hypovolaemia due to sodium loss
    • haematology
    • basic biochemistry
  • BMI
    • Below 16 leads to amenorrhoea
    • below 13 risk of sudden death
  • Osteoporosis
    • can develop after one year
    • treatment is weight gain

Referral

  • Early referral preferable
  • If
    • Non-response after couple of months
    • Rapid weight loss
    • Medical complications
  • Children of patients may require referral to services
  • May require
    • individual, group and
    • family therapy
      • Good if short (<4 yr history) and young age (<22)
    • Day hospital care
    • Inpatient care

Complications

Due to weight loss

  • Hypothermia
  • bradycardia, prolonged QT
  • Myopathy
  • Bone Marrow Suppression
  • Neuropathies
  • Amenorrhoea
  • Osteoporosis
  • Delayed Gastric Emptying
  • Liver Damage
  • Lanugo hair

Due to vomiting

  • Parotid swelling
  • Dental erosion
  • Oesophago-gastritis
  • Hypokalaemic alkalosis
  • cardiac arrhythmias
  • renal damage
  • haematemesis (Mallory-Weis tear)

Laxative abuse

  • Hypokalaemic alkalosis
  • Cardiac arrythmias
  • Cathartic (atonic) colon

Due to rapid re-feeding

  • gastric dilatation
  • gastric perforation
  • hypophosphataemia

Psychiatric

  • depression
  • re-feeding psychosis
  • Obsessive-compulsive disorder
  • alcohol dependence
  • drug abuse

Prognosis

  • death rates up to 15%
  • 1/3 recover completely
  • 1/3 improve but remain unwell
  • rest die or chronic