A Guide to Eating Disorders (PDF)

www.hacw.nhs.uk Information for Clinicians A Guide to Eating Disorders Author: Dr AP Winston, Consultant in Eating Disorders, The Aspen Centre, Warwick Worcestershire Health and Care NHS Trust Working together for outstanding care  A Guide to Eating Disorders | 3 2 | A Guide to Eating Disorders Eating disorders, although relatively common, are often a source of concern to clinicians. They can seem perplexing illnesses and professionals are sometimes unsure how to diagnose and manage them. This booklet aims to demystify eating disorders and provide a brief introduction to their recognition and treatment. What are the eating disorders? The three main eating disorders are anorexia nervosa, bulimia nervosa and binge eating disorder. In anorexia nervosa, patients limit their food intake in order to lose weight and may also control their weight with other behaviours such as self-induced vomiting, misuse of laxatives or excessive exercise. Some patients with anorexia nervosa achieve weight loss by dietary restriction alone (restricting type) while others also show bulimic behaviours such as bingeing, vomiting and laxative misuse (binge eating/purging type). In bulimia nervosa, patients binge eat and then try to compensate for this by restricting their food intake or using other weight control behaviours. In binge eating disorder, patients binge eat but do not compensate and therefore tend to be overweight or obese. Weight control behaviours The most common weight control behaviours are self-imposed starvation, vomiting, laxative abuse and excessive exercise; use of diet pills bought online is becoming increasingly common. Less common means of weight control include misuse of diuretics, use of amphetamines to suppress appetite and abuse of prescription drugs such as thyroxine. Patients with type 1 diabetes may give themselves inadequate amounts of insulin to control their weight. There is an increased prevalence of eating disorders in type 1 diabetes and undiagnosed eating disorder is a cause of unexplained poor metabolic control. What is a binge? Binge eating means eating an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances. It is often associated with a sense of loss of control over eating and patients often consume “forbidden” foods with a high carbohydrate content. Bingeing is usually followed by intense feelings of guilt, which the patient tries to relieve with periods of dietary restriction or other weight control behaviours. Clinical features of eating disorders Anorexia nervosa The cardinal features of anorexia nervosa are: • Persistent restriction of energy intake leading to significantly low body weight. A body mass index of 17.5 kg/m2 or less is often used as the cut-off for diagnosis in adults. In children and adolescents, there may be a failure to gain weight as expected. • Intense fear of gaining weight or of becoming fat or persistent behaviour that interferes with weight gain. • Disturbance in the way one’s body weight or shape is experienced, undue influence of body shape and weight on self-evaluation or persistent lack of recognition of the seriousness of the current low body weight. • Amenorrhoea is common but not universal and is no longer considered essential for the diagnosis. Other features may include: • Use of weight control behaviours • Calorie counting • Frequent weighing • Eating slowly and cutting up food very small • Chewing food and spitting it out Bulimia nervosa The cardinal features of bulimia nervosa are: • Recurrent episodes of binge eating. • Recurrent inappropriate compensatory behaviours in order to prevent weight gain, such as self-induced vomiting, misuse of laxatives, diuretics, or other medications, fasting or excessive exercise. • Self-evaluation is unduly influenced by body shape and weight • Patients tend to be of normal weight  A Guide to Eating Disorders | 5 4 | A Guide to Eating Disorders Binge eating disorder The cardinal features of binge eating disorder are: • Repeated episodes of binge eating without compensatory behaviours • Patients tend to be overweight or obese Other eating disorders: These include atypical forms of the disorders above, where some but not all the diagnostic criteria are met. This includes, for example, patients who have all the other features of anorexia nervosa but are of normal weight and patients with bulimia nervosa and binge eating disorder whose frequency of bingeing is below that specified for a full diagnosis. Other disorders are purging disorder (recurrent purging behaviour in the absence of binge eating) and night eating syndrome (recurrent episodes of eating at night). Disorders which do not meet standard criteria may be referred to as eating disorder not otherwise specified (EDNOS) or unspecified feeding or eating disorder (UFED). How common are eating disorders? Anorexia nervosa has a prevalence of around 0.2 - 0.8% among young women. The peak age of onset is between the ages of 15 and 19 and high risk groups include dancers, models and athletes. Bulimia nervosa is more common than anorexia nervosa and often begins slightly later in life; prevalence rates in young women vary between 0.5% and 2% but the prevalence of atypical forms may be considerably higher. The prevalence of binge eating disorder in the general population is probably between 1% and 3%; patients tend to be older than those with anorexia or bulimia when they present. Among those seeking treatment for obesity, as many as 30% may have binge eating disorder. Approximately 10% of those with anorexia and bulimia are male. Men and boys are often preoccupied with having a muscular physique and being “healthy” and this can be more marked than concern about weight. In binge eating disorder, approximately 35% of patients are male. Eating disorders in children Anorexia nervosa can occur in pre-pubertal children but is more common in those over the age of 12. The clinical features are similar to those in adults but failure to gain weight at the expected rate, rather than weight loss, may be the presenting feature. It is more likely that the request for help will come from parents (or sometimes teachers) than from the child. Common presenting features in younger patients include: • Concerns about weight or failure to gain weight • Delayed menarche • Irregular food intake, conflict at meal times or concern about eating with others • Preoccupation with food • Excessive exercise • Abdominal pain, gastrointestinal disturbance, headache • Mood swings, depression, anxiety, self-harm • Low self-esteem • Social withdrawal • School refusal • Anxieties about sexual development Bulimia nervosa is unusual in children under the age of 14. There is a relatively high proportion of boys with eating disorders in the younger age group. Other forms of eating disorder are relatively common in children and younger adolescents: these include psychogenic vomiting, food phobias, and selective (“faddy”) eating. Avoidant/restrictive food intake disorder (ARFID) is characterised by persistent failure to meet appropriate nutritional needs without the features of anorexia nervosa or bulimia nervosa or evidence of a disturbance in the way in which body weight or shape is experienced. In children, significant nutritional compromise can occur without weight loss and a static weight can indicate significant under-nutrition at a time of growth. BMI norms differ according to age and BMI centiles or % median.  A Guide to Eating Disorders | 7 6 | A Guide to Eating Disorders BMI should therefore be used to assess weight in those under sixteen. Children may decompensate physically more rapidly than adults and become dehydrated more easily; urgent action is required if the child’s physical health is significantly compromised. Longer term medical complications include growth retardation, pubertal arrest and reduction in peak bone mass. Physical causes of weight loss should always be excluded in children and referral to a paediatrician may be required. What causes eating disorders? The causes of the eating disorders are not fully understood but are almost certainly multi-factorial. Relevant aetiological factors may well differ from individual to individual. Possible causal factors include: • Genetic predisposition • Childhood trauma and abuse • Family difficulties • Stressful life events • Personality factors • Low self-esteem • There is continuing debate about the role of socio-cultural factors such as media pressure to conform to an unrealistic body shape Complications Psychiatric complications Depression is common in all forms of eating disorder; in anorexia nervosa, it may be due in part to malnutrition. Obsessional behaviours are also common in anorexia nervosa and may improve with refeeding. Some patients with an eating disorder self-harm. There is a sub-group of patients with bulimia nervosa who self-harm, have major problems with relationships and abuse drugs or alcohol; this is sometimes referred to as “multi-impulsive” bulimia nervosa. Medical complications Anorexia nervosa is a psychiatric disorder with major, and potentially life- threatening, physical complications which can affect any physiological system. Common/important complications include: • Bradycardia and hypotension • Hypothermia • Hypokalaemia and other electrolyte disturbances • Micronutrient deficiencies • Bone marrow suppression (anaemia, leucopenia and neutropenia, thrombocytopenia) • Neuropathy • Myopathy • ECG abnormalities (including prolonged QTc interval, which is a risk factor for cardiac arrhythmias and sudden death) • Functional bowel disturbance (often indistinguishable from irritable bowel syndrome) • Oesophagitis • Constipation • Osteoporosis The main complications of bulimia nervosa are related to weight control behaviours such as vomiting and laxative abuse: • Hypokalaemia • Dental damage • Oesophagitis • Parotid enlargement The complications of binge eating disorder are principally those of obesity.  A Guide to Eating Disorders | 9 8 | A Guide to Eating Disorders Assessment Patients with eating disorders do not always present initially to mental health services. They may present to other medical specialties with complaints such as gastrointestinal symptoms, unexplained weight loss or menstrual problems. In children, the presentation may be with vomiting or poor growth. Some patients may present with other psychiatric symptoms, such as anxiety, depression or self-harm. Often, the request for referral does not come from the patient but from the family. The first encounter with a patient who has an eating disorder can be difficult for both patient and professional. Patients, particularly if they have anorexia nervosa, are often very fearful of seeing a professional in case they are made to eat. They are likely to be feeling frightened and confused at what is happening to them. Assessment of a patient with an eating disorder is not simply a question of obtaining information and making a diagnosis. It is also the first stage in the process of engaging the patient in treatment and forming a therapeutic alliance. Sensitive handling of the patient’s fears and anxieties is essential at this stage as almost all patients are ambivalent about changing and “getting better”. It is very helpful to show an understanding of how trapped and confused the patient feels. Eating disorders often represent a “solution” to life’s difficulties and the patient has to balance the advantages of getting better against the need to relinquish a coping strategy. It is important to show an awareness of this dilemma and it is almost always unhelpful to try to frighten the patient into changing. It is often helpful to frame the process of getting better as finding new and better coping strategies. Building an understanding relationship with the patient is very important and clinicians should try to take a calm and non-judgemental approach. Patients with bulimia nervosa and binge eating disorder may be less ambivalent about change but profoundly ashamed of their eating habits; they may be embarrassed to talk about their eating problems and worried that their problem will be dismissed as trivial. Important factual information to obtain at assessment includes: • Weight and height • Duration of symptoms • Use of compensatory behaviours • Evidence of other psychiatric disorder • Symptoms and signs of physical complications Risk assessment is important. Self-harm is common in patients with eating disorders and they have a significantly increased risk of suicide. Risk assessment should also include physical risk, risk of self-neglect and risk to children as patients with eating disorders sometimes underfeed their children. A careful physical examination is essential in all patients with anorexia nervosa. A more detailed guide to the assessment of eating disorder patients is given in Appendix 1. Investigations Investigations are designed to detect important complications and exclude other disorders which may mimic an eating disorder. The following investigations are recommended at initial assessment: Anorexia nervosa • Full blood count • U and E • Glucose • LFT • Calcium and phosphate • Magnesium • B12 and folate • TFT • CRP • ECG • Consider DXA scan  A Guide to Eating Disorders | 11 10 | A Guide to Eating Disorders Bulimia nervosa • Full blood count • U and E • Glucose • LFT • Magnesium if prolonged/severe vomiting or misusing laxatives, diuretics or alcohol • B12 and folate • ECG if evidence of electrolyte disturbance, cardiac symptoms, vomiting or misuse of laxatives/diuretics Patients with binge eating disorder should be investigated as for obesity. Treatment Most eating disorders can be treated on an outpatient basis. Treatment normally consists of some form of psychological therapy, together with nutritional interventions such as weight restoration or dietary stabilisation. Drug treatment plays a relatively small role in the treatment of eating disorders but fluoxetine may be used in bulimia nervosa and binge eating disorder; medication may also be needed to treat psychiatric or medical complications. Cognitive-behavioural therapy is widely used for bulimia nervosa; more complex patients, such as those with co-morbid personality disorders, may require other forms of therapy. A variety of approaches are used for anorexia nervosa including cognitive-behavioural, psychodynamic and supportive therapy; family therapy is useful for younger patients. Psychotherapy for anorexia nervosa may need to be prolonged. The optimum treatment for binge eating disorder is not yet established but cognitive-behavioural therapy, similar to that for bulimia nervosa, is often used; psychological treatment is used to normalise the patient’s eating pattern but additional interventions are often required to promote weight loss. Treatment of eating disorders in children and younger adolescents is based around involvement of the family and helping the parents to manage the child’s eating. This usually involves some form of family therapy but individual therapy sessions for the child may also be offered. Inpatient treatment is reserved for the most severe cases. It is used mostly for anorexia nervosa but patients with complex bulimia nervosa occasionally require admission. In anorexia nervosa, treatment may be aimed at short-term stabilisation or restoration to a healthy weight. In the latter case, treatment combines re-feeding with intensive psychotherapy and usually takes several months. It is important that the patient opts in to treatment if at all possible. In extreme situations, however, treatment can be carried out under the Mental Health Act; this includes nasogastric feeding if required. Indications for admission include: • Very low weight or rapid weight loss • Serious physical complications • Severe psychiatric co-morbidity • Failure of outpatient treatment • Occasionally, need for separation from family The electrolytes should be monitored in patients who are vomiting or abusing laxatives/diuretics. In those who are abusing laxatives/ diuretics, or in prolonged/severe vomiting, this should include the plasma magnesium. Hypokalaemia should be treated with potassium supplementation (eg Sando-K) and the plasma potassium maintained within the normal range. A broad spectrum vitamin and mineral supplement (eg Forceval) is generally indicated in anorexia nervosa; vitamin preparations containing vitamin A should be avoided in pregnancy. Anaemia in severe anorexia nervosa is often due to bone marrow suppression; treatment with iron is likely to be ineffective even if the picture is of iron deficiency and may be dangerous in the presence of untreated malnutrition. B12 and folate deficiency should be treated in the normal way.  A Guide to Eating Disorders | 13 12 | A Guide to Eating Disorders Appendix 1 Assessment of Eating Disorder Patients Assessment should follow the normal format for a psychiatric assessment but with the following additions/modifications: History of eating disorder • Nature of the eating disorder (dietary restriction, binge eating etc) • History of weight change since the onset of the eating disorder. Include precipitants and relationship to life events • Dietary restriction – does the patient limit intake to a specific number of calories? Specific types of food avoided • Highest and lowest adult weight • Does the patient restrict fluids? Compensatory behaviours • Bingeing – how many times per day/week? • Vomiting – how many times per day/week? • Laxatives, diuretics, emetics, appetite suppressants, weight loss drugs, amphetamines, caffeine – how many/much per day/week • Exercising – what sort, how many hours per day/week? • Diabetics – omission or under-use of insulin to control their weight Attitudes to weight and shape • Does the patient feel fat/dislike their body? • Distorted body image • Does the patient weigh themself? If so, how often? • Does the patient check/measure their body (using measurements or with hands/clothes) Current diet • Typical day’s eating Menstrual history • Current menstrual cycle • Age of menarche • Use of contraceptives/HRT Physical symptoms • Neurological: dizziness, blackouts, headaches, numbness, paraesthesiae • Cardiovascular and respiratory: palpitations, chest pain, breathlessness • Gastrointestinal: bowels, bloating, abdominal pain, vomiting • Skin: sores, dry skin, feeling cold • Teeth: dental erosion Psychiatric symptoms • Depression • Anxiety • Obsessional symptoms • DSH/suicidal thoughts Past psychiatric history • Previous admissions/outpatient treatment • Other psychiatric illness Past medical history • A detailed medical history is important Current medication • Include over-the-counter medicines, vitamins and nutritional supplements Drug and alcohol use • Include caffeine, nicotine, amphetamines Family history • Family history of eating disorder or obesity • Family history of other mental illness • Family history of physical illness Personal history • As normal, but emphasise early family relationships and relationship of life events to eating disorder • Early experiences of neglect and abuse are particularly important  A Guide to Eating Disorders | 15 14 | A Guide to Eating Disorders Mental State Examination • Look for evidence of body image disturbance, fear of fatness, attitudes to food and weight • Screen for other psychiatric disorder (depression, OCD, psychosis etc) • Ask about thoughts of DSH • Ask about patient’s expectations and hopes of treatment. Do they regard themself as having a problem? Do they have any thoughts about what sort of treatment they want? Physical Examination • General examination including height, weight and BMI • Weight should be done in light clothing and without shoes; the patient should be asked to remove heavy belts etc and empty pockets of heavy objects • Pay particular attention to fluid status (dehydration, oedema) and cardiovascular function • Check core temperature Appendix 2 Further Reading Helping People with Eating Disorders: A Clinical Guide to Assessment and Treatment by Robert Palmer (WileyBlackwell; ISBN: 047198647X/978-0471986478) A good introduction to the subject The Essential Handbook of Eating Disorders, edited by Janet Treasure, Ulrike Schmidt and Eric van Furth (WileyBlackwell; ISBN: 0470014636/978-0470014639) A more detailed, multi-author textbook Appendix 3 Information for Patients B-eat, the eating disorders charity, provides information and support for both patients and their families www.b-eat.co.uk Helpline: 08456 341414 Youthline: 08456 347650 TXT: 07786 20 18 20 The Royal College of Psychiatrists publishes information leaflets which can be downloaded free of charge from their website: www.rcpsych.ac.uk/mentalhealthinfoforall/problems/eatingdisorders/ eatingdisorders.aspx Books on anorexia nervosa • Overcoming Anorexia Nervosa by Christopher Freeman and Peter Cooper (Robinson; ISBN: 1854879693/978-1854879691) • Overcoming Anorexia by J Hubert Lacey, Christine Craggs-Hinton and Kate Robinson (Sheldon Press; ISBN: 0859699862/978-0859699860) Books on bulimia nervosa and binge eating disorder • Overcoming Binge Eating by Christopher Fairburn (Guilford Press; ISBN: 0898621798/978-0898621792) • Getting Better Bit(e) by Bit(e) by Janet Treasure and Ulrike Schmidt (Psychology Press; ISBN: 0863773222/978-0863773228).  Do you have a communication or information support need? If so please contact the person who gave you this leaflet so that those needs can be recorded and responded to. @WorcsHealthandCareNHS @ WorcsHealthCare Acknowledgement: Coventry and Warwickshire Partnership Trust