Eating disorders are a fairly rare form of child mental health disorder, but they can cause considerable morbidity in childhood and adult life.
Anorexia nervosa, which is defined as refusal to maintain body weight, intense fear of gaining weight, disturbed body image and amenorrhoea, has been reported in children as young as eight.
Bulimia nervosa, which is defined as binge eating, actions to prevent weight gain and self-evaluation unduly centred around weight and shape, is not seen until adolescence. Some young people have abnormal eating behaviours which do not fit into either diagnostic category.
Much of the presentation of eating disorders in young people is similar to that in adults. However, there are some differences.
A young person with an eating disorder most commonly presents in primary care accompanied by a concerned parent or carer who gives a collateral history suggestive of an eating disorder. Eating disorders might also be discovered when a young person presents with physical symptoms such as apparently unexplained weight loss, fainting or vomiting. More rarely, older adolescents might present on their own asking directly for help with eating.
Full-blown anorexia nervosa is often easy to diagnose; the much more difficult task is engaging the patient. Typically, the young person is less concerned about their difficulties than everyone else: they might maintain there is nothing wrong, minimise their difficulties, take issue with a parent's description or refuse to talk.
An angry, defensive teenager who contradicts everything his or her parents say is a formidable patient to deal with in a brief interview. Making time for one or two longer consultations might be helpful.
It is easy to underestimate the intense psychological 'stalemate' of a young person with an eating disorder.
Although they might appear unmoved, they are painfully aware of their uncomfortable position. However, the prospect of giving in to demands to eat more or to stop vomiting is just as difficult and often frightening.
It might be easier to stay empathic with a surly adolescent by remembering that they are trapped in this profound psychological dilemma.
Young people tend to admit more readily to physical symptoms. Talking about how lethargy, dizziness, feeling the cold, dry skin and hair, and menstrual irregularities are signs that a body is under strain might allow you to get agreement from the patient that something is wrong.
As eating disorders worsen, low energy levels, low mood and preoccupation with eating contribute to young people withdrawing from leisure pursuits.
Young people might concede that they have given up things they used to like to do.
If the diagnosis is obvious from the history it can be helpful to say its name. It is also often helpful to externalise the eating disorder and talk about it as an illness, force or 'bully' that has taken over part of a person and their life. This idea of the eating disorder being separate from the young person can also enable families to get tougher with the disorder, not the child underneath.
Some pointers of what to suggest after the initial consultation are shown in the box below. The aim is to help families feel more informed and ready to take more control of their child's eating behaviour. Everyone must remember that rapid change is not usually possible.
Accurate measurements of weight and height are essential parts of the assessment; calculate the BMI or, for children, plot measurements on an up-to-date centile chart. Sometimes young people who do not want to know their weight stand backwards on the scales.
Exclude other causes of significant weight loss, including diabetes mellitus, inflammatory bowel disease, hyperthyroidism and severe depression.
Similarly, in a child who is vomiting repeatedly, consider primary abdominal pathology or metabolic disease.
Request full blood count, urea and electrolytes, liver function tests and thyroid function tests to exclude anaemia, hypokalaemia, metabolic disturbances of starvation and hyperthyroidism. In emaciated patients a baseline electrocardiogram is helpful.
Children and adolescents with established eating disorders need to be referred for specialist dietary, paediatric and mental health assessment.
Recent NICE guidance has set standards for the treatment of anorexia nervosa in all age groups.
- Dr Thompson is consultant in child adolescent psychiatry at Lincolnshire Partnership NHS Trust
DIFFERENCES IN CHILDREN AND ADULTS
- Younger children might give only rudimentary accounts of disturbed body image or fear of weight gain.
- In the adolescent growth spurt, deteriorating anorexic patients might maintain their weight.
- Amenorrhoea is an unreliable clinical sign in girls around the menarche.
- Significant weight loss in children is more serious than in adults: children might become more acutely unwell and they face potential long-term health problems.
INITIAL CONSULTATION ADVICE
- Encourage young people and families to seek information about their disorder.
- Encourage the young person with their family's help to keep their eating behaviour as it is: it may be premature to expect improvement but it is important to prevent further deterioration.
- Keep normal family routines going as far as possible.
- Ensure everyone has some good time for themselves regularly.
info/mhgu/newmhgu24.htm - Royal College of Psychiatrists factsheet: eating disorders in young people
www.edauk.com - Eating Disorders Association.