Eating Disorders: Anorexia Nervosa

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Eating Disorders Anorexia Nervosa Bulimia
Nervosa

• Helen Keeley
• January 2002

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Eating Disorders. (ICD F50)

• Two syndromes are described separate (ICD 10 )or
  on continuum (DSM1V)-
• Anorexia Nervosa (restricting type)
• Bulimia. (purging/ binging type)
• Overeating and Vomiting associated with
  psychological disturbances are also described.
• Anorexia
• peak onset in the mid-teens and a female male
  ratio of 101.
• Prevalence is 0.1 in 11-15 1 in 15-18 year old
  girls
•  Twin studies suggest genetic predisposition
  important esp. for AN. Cultural factors also very
  important and AN is largely disorder of developed
  world.

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Anorexia Nervosa. Description of syndrome

• Disorder characterised by
• Deliberate weight loss induced and/or sustained
  by the patient.
• Occurs most commonly in adolescent girls or young
  women but boys may also be affected, as may
  children approaching puberty and women up to the
  menopause.
• The disorder is associated with under nutrition
  of varying severity, with resulting secondary
  endocrine and metabolic changes and disturbances
  of bodily function.
• Differential diagnosis includes
• depression obsessional states somatic causes
  of loss of appetite.

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Anorexia Nervosa. Diagnostic Criteria

• For a definite diagnosis all of the following are
  required
• Bodyweight is maintained at least 15 below that
  expected or Quetelets body-mass index
  (weight(kg)/height(m)2)is 17.5 or less (gt14
  implies admission) Also failure to make expected
  weight gain during growth period in prepubertal
  children.
•  Weight loss is self-induced and may include
  self-induced vomiting, purging, excessive
  exercise, and use of appetite suppressants and /
  or diuretics.
•  Body- image distortion and dread of fatness as
  an intrusive, overvalued idea.
• Widespread endocrine disorder involving the
  hypothalamic-pituitary-gonadal axis, manifested
  in women as amenorrhoea (except if on OCP) and in
  men as loss of sexual interest and potency.
• If onset is prepubertal, development of
  secondary sexual characteristics may be delayed
  or arrested

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Bulimia NervosaDescription of syndrome

• Syndrome characterised by repeated bouts of
  overeating and an excessive pre-occupation with
  the control of body weight.
• The age and sex pattern is similar that of
  Anorexia Nervosa but the age of presentation
  tends to be slightly later.
• The disorder may be a sequel to Anorexia but the
  opposite may also occur.
• Repeated vomiting may give rise to disturbances
  of body electrolytes, physical complications
  (tetany, epileptic seizures, cardiac arrhythmias,
  muscular weakness) and further severe loss of
  weight. 

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Bulimia Nervosa Diagnostic Criteria

• For a definite diagnosis all of the following are
  required1. There is a persistent
  preoccupation with eating and an irresistible
  craving for food leading to bingeing 2.
  Counteraction of the fattening effects of the
  food occurs by one of more of the following
  self-induced vomiting purgative abuse
  alternating periods of starvation use of drugs.
  If IDDM, may neglect insulin treatment.3.
  Psychopathology consists of a morbid dread of
  fatness and a sharply defined weight threshold is
  set that is well below the optimum. 

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Bulimia Nervosa Signs and Symptoms

• Not as severe as Anorexia Nervosa unless occurs
  as a complication thereof, when it indicates poor
  prognosis.
• Weight may be average or slightly above or below
• Similar but less extreme body- image distortion
  to AN
• Marshalls sign, i.e. lesions on the knuckles
• Parotid Enlargement
• Dentists may well notice characteristic effects
  of self-induced vomiting including
• caries which commence at the back of the front
  teeth
• scarring at back of throat from nail abrasions

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Prognosis TreatmentAnorexia Nervosa

• Long term Prognosis
• 50 recover 30 partly improved
• 20 run chronic coursegt5 mortality
• Minority progress from restrictive to binge and
  then to BN
• Good prognostic features
• Early onset good parent- child relationships
  early detection and treatment.
• Poor Prognostic indicators
• Greater weight loss vomiting binge-eating
  greater chronicity and premorbid abnormalities.
• Treatment
• Can occur on out-patient basis. Gradual but
  steady weight restoration is aim within 10 of
  expected weight.
• Family Rx to restructure parent child
  relationships individual Rx. Include
  behavioural antidepressants for weight gain and
  depression

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Prognosis TreatmentBulimia Nervosa

• Under-represented in clinical samples but studies
  suggest that it may be more common in the general
  population.
• Prognosis
• Often episodic course with remissions and
  relapses. Long term disturbed eating persists and
  depression is common
• Treatment
• Outpatient with cognitive-behavioural or group
  Rx. (better than meds.)