Eating Disorders Flashcards
What is the ICD-10 criteria for Anorexia Nervosa?
The ICD-10 criteria for Anorexia Nervosa require the following characteristics:
- BMI is <17.5 (or weight is 15% less than expected - as some teenagers may never reach their expected weight).
- Deliberate weight loss - self-induced vomiting; self-induced purging; excessive exercise; use of appetite suppressants and/or diuretics.
- Body-image distortion - patients are preoccupied with body shape and weight. They hold an overvalued idea that they are fat even though they are thin.
- Endocrine dysfunction resulting in amenorrhea in women and impotency or loss of libido in men.
What are the key features of Bulimua Nervosa?
Whereas Bulimia Nervosa requires the following criteria:
- Binge eating - persistent preoccupation with eating, and an irresistible craving for food.
- The patient attempts to counteract the ‘fattening’ effects of food by purging, starving and other strategies.
- Overvalued ideas concerning shape and weight, of the type seen in anorexia nervosa.
What is the key difference between anorexia nervosa and bulimia nervosa?
The main difference is that in anorexia, the patient is anorexic and therefore has the physical consequences; In bulimia nervosa BMI is >17.5 and periods are usualy normal/
Bingeing and vomiting can occur in anorexia, but BN should be diagnosed if this is the predominant behaviour and the patient is not underweight.
What are the physical consequences of anorexia?
- General - cold and lethargy are common general complaints. Cytopenias causing anaemia and recurrent infections are also common.
- Cardiovascular effects are common and seen in 80% of patients. Commonly seen as bradycardia, hypotension and arrhythmias (often secondary to hypokalaemia).
- Gastrointestinal problems can be due to vomiting, such as oesophageal tears and gastric rupture, and also include stomach pain and peptic ulcers and constipation. Patients often feel bloated after eating small amounts due to delayed gastric emptying.
- Reproductive - women suffer from amenorrhoea, which is a criterion for anorexia nervosa. Commonly seen is low FSH and LH as well as oestrogens and testosterone.
- Musculoskeletal - osteoporosis leads to fractures and proximal myopathy is often severe.
- Neurological - peripheral neuropathy, delirium, convulsions and even coma may occur.
What are the physical signs of malnutrition?
Signs of malnutrition include:
- Fine lanugo hair
- Emaciation (being very thin)
- Reduced sexual maturation
- Blue/cold extremities
- Oedema
- Hypercarotenaemia (yellow skin tinge especially in soles and palms)
What are the physical signs of purging/vomiting?
Signs of purging/vomiting:
Russell’s sign - calluses or cuts on the knuckles from self-induced vomiting
Swollen salivary glands often seen as a puffy face
Tender abdomen
Erosion of dental enamel and caries
Describe the investigations/assessment of a patient with eating disorder
Physical investigations include:
- Height, weight and BMI (weight/height2).
- Squat test - Ask the patient to squat down and rise without the use of their arms.
- Measure core temperature
- Examine peripheries and perform a cardiovascular examination looking for postural hypotension
Bio-chemical investigations:
- FBC, U&Es, LFTs, creatine kinase, glucose
- ESR and TFTs to look for organic causes
- ECG investigating bradycardia, arrhythmias or long QT interval.
Psychosocial investigations [NICE]:
- Assess the person’s motivation to change their eating habits
- Determine the patients’ views on the consequences of their eating habit
- Asses risk of suicide
- Asses for concomitant psychological disorder such as depression, anxiety, OCD
- Enquire about their level of psychosocial support
Describe the management of eating disorders
- Assess risk of self-harm
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Assess physical health properly and consider admitting to hospital if:
- BMI <13 or extremely rapid weight loss
- Serious physical complications
- High suicide risk
- Assess for co-existing psychological disorders
Refer patients to a community mental health team (CMHT) or CAMHS or a specialist eating disorder unit. They will usually initiate psychotherapies such as:
- Motivational interviewing - this is important especially if the patient lacks insight, or holds positive views about their disorder.
- Family therapy involves the whole family and is particularly useful for early-onset patients under the age of 19.
- Interpersonal therapy and Cognitive behavioural therapy can be used for latter parts of therapy, improving social functioning and self-esteem.
While waiting for referral, manage physical health issues such as hypokalaemia, arrhythmias, gastrointestinal disease.
The waiting time is between 6-18 weeks.
SSRIs such as fluoxetine can be used in bulimia nervosa to reduce bingeing and purging
What are the differential diagnoses for Anorexia Nervosa?
- Medical causes of weight loss such as hyperthyroidism, malignancy, AIDS, gastrointestinal disease, Addison’s disease, chronic infection, inflammatory conditions.
- Depression - weight loss can be severe in depression, however it would not be denied, unlike in anorexia nervosa.
- Bulimia nervosa - bingeing and vomiting can occur in anorexia, but BN should be diagnosed if this is the predominant behaviour and the patient is not underweight.
- Eating Disorder Not Otherwise Specified (EDNOS)
- Body dysmorphic disorder (BDD) is characterised by body image distortion, however deliberate weight loss in BDD would be unusual.
- Psychosis - self-starvation might occur if food is believed to be poisoned.
What are biochemical features of anorexia?
Biochemically everything is low (hypokalemia, low T3, low LH/FSH, testosterone) apart from G’s and C’s raised: growth hormone, glucose, salivary glands, cortisol, cholesterol, carotinaemia.
What psychotherapy is contraindicated in eating disorders?
Psychoanalysis is contraindicated in eating disorders.
What are the indications for admission for eating disorders?
- BMI <13 or extremely rapid weight loss
- Serious physical complications
- High suicide risk
