Anorexia Nervosa Flashcards
Anorexia nervosa is an eating disorder characterised by restriction of energy intake resulting in low body weight and an intense fear of weight gain.
Anorexia nervosa is an eating disorder characterised by restriction of energy intake resulting in low body weight and an intense fear of weight gain.
Though anorexia nervosa may occur at any age, the risk is highest in
Though anorexia nervosa may occur at any age, the risk is highest in young people between the ages of 13-18 years old.
It is estimated that the lifetime prevalence of anorexia nervosa is …% in women
It is estimated that the lifetime prevalence of anorexia nervosa is 2-4% in women.
Though little is understood about the aetiology of anorexia nervosa, a number of risk factors have been identified.
Female gender
Age (most commonly affects adolescents and young people)
Family history of eating disorders, depression, or substance abuse
Previous criticism of eating habits and weight
Increased pressures to be slim (e.g. ballet dancers, models, athletes)
History of sexual abuse
Low self-esteem
Obsessive personality
Emotionally unstable personality disorder
Clinical features of anorexia nervosa
Restriction of energy intake Low body weight Features of body dysmorphia Intense fear of weight gain Rapid weight loss Aggressive weight-loss techniques (laxatives, diuretics, vomiting) Often a lack of insight or denial Withdrawal from social settings
SCOFF screening questionnaire
The SCOFF questionnaire is a short and simple tool that can be used in primary care to help identify patients that may be suffering with …
SCOFF screening questionnaire
The SCOFF questionnaire is a short and simple tool that can be used in primary care to help identify patients that may be suffering with an eating disorder.
SCOFF screening questionnaire …
S – Do you make yourself Sick because you feel uncomfortably full?
C – Do you worry you have lost Control over how much you eat?
O – Have you recently lost more than One stone (6.35 kg) in a three-month period?
F – Do you believe yourself to be Fat when others say you are too thin?
F – Would you say Food dominates your life?
Two or more positive responses is considered indicative of anorexia nervosa or bulimia nervosa.
The following are noted as criteria for a diagnosis of anorexia nervosa:
DSM-V criteria
Restriction of energy intake relative to requirements, leading to a significantly low body weight in the context of age, sex, developmental trajectory, and physical health; significantly low weight is defined as a weight that is less than minimally normal or, for children and adolescents, less than that minimally expected.
Intense fear of gaining weight or of becoming fat, or persistent behaviour that interferes with weight gain, even though the patient’s weight is already significantly low.
Disturbance in the way in which one’s body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or persistent lack of recognition of the seriousness of the current low body weight.
Assessment in anorexia nervosa
Detailed information on the assessment of both adults and those under the age of 18 have been published by the Royal College of Psychiatrists:
MARSIPAN (over age 18) Junior MARSIPAN (under 18)
Examination in anorexia nervosa
Vital signs: bradycardia, hypothermia and postural blood pressure drop are all red flags for severe disease.
Sit-up, Squat–stand test: tests the patient’s ability to sit up from lying and to squat down and stand back up. Scored from 0-3 with increasing risk with lower scores:
0: unable to complete action
1: requires the assistance of upper limbs
2: noticeable difficulty
3: no difficulty
Investigations for anorexia nervosa
ECG: bradycardia, prolonged QT interval or arrhythmias are all signs of high-risk disease requiring urgent review.
Blood sugar: significant malnutrition can result in hypoglycaemia (also consider diabetes as a cause of unexplained weight loss).
Blood tests: consider FBC, LFTs, renal function, bone profile, magnesium, thyroid profile. This allows review for anaemia, electrolyte disturbance and thyroid dysfunction amongst other abnormalities. In severe malnutrition mild derangement of liver function tests is common.
Additional: pregnancy test should be considered where appropriate. Hormonal panels may be indicated in women with menstrual dysfunction. Further tests may be required depending on the given individual presentation.
Management of anorexia nervosa
When possible, care is based in the community, with patients receiving talking therapies and supervised weight gain.
Most patients will be managed in the community. Talking therapy and supervised weight gain form the cornerstone of care. Patients who do not respond to outpatient management or present with high-risk features or those that cause immediate concern should be considered for inpatient care.
Inpatient/urgent care in anorexia nervosa
Inpatient/urgent care
In those at risk of significant risk of complication or with severe disease (e.g. bradycardia, ECG changes, electrolyte abnormalities, very low BMI, rapid weight loss, dehydration, organ failure, suicide risk), admission to hospital is required. It may also be considered if patients fail to respond to community management.
Specialist eating disorders units are able to provide most care including (from MARSIPAN): ‘nasogastric insertion and feeding, daily biochemical tests, frequent nursing observations, prevention of symptomatic behaviours (water drinking, absconding, exercising, etc.), daily ECG, sedation of a resisting patient, use and management of mental health legislation, treatment of pressure sores, immediate cardiac resuscitation without presence of ‘crash’ team’.
Inpatient/urgent care - anorexia nervosa
They are typically unable to provide ‘intravenous fluids, artificial ventilation, cardiac monitoring, central venous pressure lines, total parenteral nutrition, cardiac resuscitation (‘crash’) team, treatment of serious medical complications’. These patients need admission to a hospital under the care of a medical team with ongoing psychiatric input.
The management of severely ill patients with anorexia nervosa is covered in detail in the MARSIPAN and Junior MARSIPAN guidelines. A full re-wording or that is beyond the scope of this note. Input for these patients needs to come from psychiatrists, medics and dieticians. Use of the Children Act 1989 or Section 3 of the Mental Health Act may be required, though this is used as a last resort.
Refeeding risk - anorexia nervosa
Refeeding syndrome is a potentially fatal complication and is covered in some detail in the MARSIPAN & Junior MARSIPAN guidelines. It occurs in malnourished patients who then receive a sudden increase in their calorific intake resulting in electrolyte abnormalities and fluid retention. We cover the pathophysiology in our Refeeding Syndrome note.
The aim is to avoid refeeding syndrome and undernutrition. Some factors that increase the risk of refeeding syndrome are: