September 2008: GPs should be vigilant for eating disorders
How can eating disorders be recognised?
When is referral indicated?
What treatments can GPs initiate?
How can eating disorders be recognised?
When is referral indicated?
What treatments can GPs initiate?
Eating disorders are psychiatric disorders resulting in impaired physical or psychosocial functioning caused by disturbances of eating habits or weight-control behaviour. The diagnosis of eating disorder is only appropriate if the symptoms cannot be attributed to another medical or psychiatric condition.
Eating disorders have a serious impact on the lives of patients and their families. Quality of life is significantly impaired across a variety of domains, including work or education, physical health and the patient's sense of self and wellbeing. Eating disorders have a greater negative impact on quality of life than mood disorders,1 and in girls and young women aged 15-24 eating disorders are the fourth greatest disease burden in terms of years of life lost through death or disability.2 This impact is exacerbated by the chronic nature of the illness and the associated physical and psychiatric comorbidity.
The main ICD-10 subdivisions of eating disorders are anorexia nervosa, bulimia nervosa (including atypical variants) and eating disorder unspecified. These divisions can be useful when considering disease aetiology, prognosis and treatment. However, the clinical reality is that patients often move between diagnoses and a large proportion of patients do not fit neatly within these categories.3 Futhermore, evidence-based treatment for atypical and unspecified eating disorders is very limited, so it may be necessary to model treatment on the condition that most closely matches a patient's symptoms.
Anorexia nervosa is ten times more common in women than men. However, recent community studies suggest the prevalence in boys and men may be significantly underreported.4,5 In primary care settings in the UK, the incidence is highest in girls and young women aged 10-19 years,6 and the point prevalence in young women is 0.3%.7
It is important to note that community studies have found that half of cases remain undetected, so the true incidence is likely to be considerably higher than previously reported.8
Bulimia nervosa is more common than anorexia nervosa, with a point prevalence in young women of 1%.7 However, when cases which fail to meet the strict diagnostic criteria are included the prevalence rises to 5.4%.9 There was a decline in the number of cases of bulimia nervosa identified in primary care in the latter half of the 1990s.6,10 Further research is needed to see if this trend has continued into the 21st century.
Only a very small proportion of cases will enter the mental healthcare system, underlining the importance of identifying the disorder in primary care.
• Body weight at least 15% below that expected or BMI ? 17.5kg/m2
• Self-induced weight loss
• Body image distortion as a persistent, intrusive, overvalued idea
• Endocrine disorder involving the hypothalamic–pituitary–gonadal axis (evidenced by amenorrhoea, except in patients prescribed HRT)
• Delayed or arrested pubertal events if onset is pre-pubertal.
Case study 1, left, represents a typical presentation of anorexia nervosa in primary care.
• Episodes of overeating, in which large amounts of food are consumed in a short time, characterised by a feeling of loss of control
• Attempts to counteract the fattening effects of food by one or more of the following methods: vomiting; excessive exercise; alternating periods of starvation; and misuse of medical therapies (including appetite suppressants, diuretics, laxatives, thyroid replacement or omission of insulin)
• Psychopathology includes a dread of fatness and self-imposed low weight threshold (below pre-morbid weight or healthy weight).
See case study 2, left, for an example of how a patient with bulimia nervosa might present in primary care.
The NICE guideline on eating disorders recommends the use of screening tools in primary care.12 Screening efforts should target:
• Young women with a low BMI
• Patients of normal weight who reveal weight concerns
• Women with menstrual difficulties
• Patients with gastrointestinal symptoms
• Patients with physical signs of malnutrition or repeated vomiting
• Children with poor growth.
The SCOFF questionnaire13 is a useful screening instrument, which has been validated in primary care settings. This instrument includes five questions:
• Do you make yourself Sick because you feel uncomfortably full?
• Do you worry you have lost Control over how much you eat?
• Have you recently lost more than One stone in a three month period?
• Do you believe yourself to be Fat when others say you are too thin?
• Would you say that Food dominates your life?
Two or more positive responses indicate a likely case of anorexia or bulimia nervosa.
If GPs have a high index of suspicion that a patient has an eating disorder they should take a full psychiatric and medical history. In some cases, it may be helpful to include a separate history from a family member or carer if the patient is willing.
Although physical examination can provide information about the risk associated with the eating disorder, GPs should conduct a full risk assessment, covering psychological and social parameters and evaluate the patient's insight. Patients are often unaware of the seriousness of their condition.
Characteristics of the history that may be associated with increased risk include: excessive exercise with low weight; haematemesis; combined restriction of food and fluid; rapid weight loss or interruption of ritualised eating habits (eg during holidays or exams).
Treatment and referral
The treatment for anorexia nervosa is primarily psychological and medication should not be used as the sole or primary treatment.12 The Royal College of Psychiatrists recommends referral for patients with a BMI below 17kg/m2, and urgent referral if the patient's BMI is below 15kg/m2 or there is evidence of organ failure.13
Most patients with anorexia nervosa will be treated as outpatients and a variety of approaches have been shown to be effective. Family therapy is the treatment of choice in adolescent patients and achieves good outcomes in up to 60% of cases. In adults, cognitive analytical therapy, cognitive behaviour therapy (CBT), interpersonal therapy, family therapy or focal psychodynamic therapy can all be effective.12
Inpatient treatment should be considered for patients with any of the following:
• Severe emaciation (BMI <15kg/m2)
• Rapid weight loss
• Evidence of organ failure
• Significant risk of self-harm or suicide
• No improvement despite appropriate outpatient treatment.
The use of a stepped care model is appropriate in patients with bulimia nervosa, and self-help can be useful as a first step in treatment. This can be successfully implemented in primary care and GPs can facilitate the recovery process.15 Providing minimal guidance improves the effectiveness of self-help therapy, and four
face-to-face sessions or simple telephone guidance is enough to increase efficacy.16
Antidepressants may also have a role in the treatment of bulimia nervosa. Although no trials have directly compared antidepressant classes or doses, SSRIs, MAOIs and tricyclics are all more effective than placebo in reducing the frequency of binge eating and purging.12 However, patients may prefer not to use tricyclics because of the side-effects caused by these drugs. High doses are needed to treat bulimic symptoms, and the effective dose of fluoxetine is 60mg.17
There is strong evidence that CBT should be the treatment of choice for patients with bulimia nervosa.12
One-third of patients can be expected to make a complete recovery and a substantial proportion ‘much improved'. Similar outcomes are possible with interpersonal therapy; however, it may take up to a year longer to achieve results comparable with those achieved by CBT.
Patients who are purging daily or have significant comorbidity should be referred to specialist services.14
Support for carers
Caring for someone with an eating disorder is associated with high levels of distress and increased risk of mental health complaints.18,19 Carers may benefit from a specific needs assessment and may require ongoing support from their GP.
A variety of psychoeducational interventions have been developed specifically for family members and their effectiveness is currently being evaluated.20
Eating disorders are a relatively common presentation in primary care, especially in young women. However, a large proportion of patients remain undiagnosed. Increased awareness among GPs can facilitate early treatment of these conditions. When combined with evidence-based treatment this can lead to improved outcomes. Brief screening by GPs is a crucial step in this process.Author
Dr Laura G Currin
King's College London
1 Cooper PJ. Bulimia Nervosa and Binge-eating: A Guide to Recovery. London: Robinson 1993
2 Fairburn CG. Overcoming Binge Eating.
New York: Guilford Publications 1995
3 Schmidt U, Treasure J. Getting better bit(e) by bit(e): A Survival Kit for Sufferers of Bulimia Nervosa and Binge Eating Disorders. London: Lawrence Erlbaum Associates 1993Further information
A complete guide to risk assessment, as well as additional information for clinicians, patients and carers,
is available from the Institute of Psychiatry website www.eatingresearch.com
beat is a UK charity providing information and support for patients with eating disorders and their families
helpline: 0845 634 1414 www.b-eat.co.uk
Maudsley Parents is an independent organisation for the parents of children with eating disorders and includes information on family-based treatment
Treasure J. Anorexia nervosa: A Survival Guide for Families, Friends and Sufferers. Hove: Psychology Press 1997Key points GPs should be vigilant for eating disorders casestudy1 casestudy2 Box1