Clinical Features

Anorexia Nervosa

Anorexia Nervosa (AN) is characterised by:

• A morbid fear of fatness.
• A distorted body image.
• Weight loss with a BMI of 17.5 kg/m2 or less.
• Amenorrhoea (cessation of periods) in females.

People with AN generally eat very little, often between 600 and 1000 kilocalories per day and are self conscious of eating in public. Associated social isolation is common. Encouragement to eat by other people may trigger resentment and deliberate hiding of food.

Some people with AN also engage in binge eating and self induced vomiting or the misuse of laxatives, diuretics (water tablets), enemas or amphetamines.

Associated clinical features may include:

• Psychological features
  • Depressive symptoms
  • Perfectionist traits
  • Fear of sexuality
  • Obsessive compulsive symptoms
  • Social isolation
  • Preoccupation with food (e.g. may enjoy preparing elaborate meals for others yet avoid eating in company)
  • Hyperactivity (e.g. vigorous exercise to lose weight)
  • Increased risk of self harm and suicide
• Physical features
  • Anaemia
  • Bradycardia (slow pulse)
  • Cold intolerance
  • Constipation
  • Fatigue
  • Fine “downy” hair on body
  • Hypothermia
  • Muscle weakness
  • Osteoporosis (thinning of bones)
  • Hypotension (low blood pressure)

Bulimia Nervosa

Bulimia Nervosa (BN) is characterised by:

• Fear of fatness.
• Episodes of binge eating.
• Self induced vomiting (or other extreme methods to compensate for overeating e.g. laxatives, fasting or drugs).

There is a high incidence of associated depression (about 35 to 40%) and obsessive compulsive symptoms (22%).

People with BN are usually of normal weight or slightly overweight.

Associated clinical features include:

• Major weight fluctuations
• Poor dental hygiene with pitting and acid erosion of teeth
• Arrhythmias (abnormal heart rhythms) due biochemical disturbance
• Cardiomyopathy (damage to heart muscle) caused by ipecacuanha abuse (substance used to induce vomiting)
• Pancreatitis (inflammation of the pancreas)
• Oesophageal tears
• Dilatation and rupture of the stomach
• Severe constipation and dilated colon
• Muscle weakness due to potassium loss
• Rarely renal damage, tetany (painful muscular spasms due to calcium loss) and epileptic fits may occur.

Eating disorder not otherwise specified (EDNOS or atypical eating disorders)

The clinical features of EDNOS are similar to those of AN and BN.  However the frequency or severity of the symptoms may not reach the threshold for diagnosis of AN or BN although the clinical disability may be similar. 

Amended June 2008