Eating Disorders Flashcards
What is the epidemiology of anorexia nervosa?
Incidence is 1%
10 times more common in women
Usually begin in teens
What are the symptoms of anorexia nervosa?
Refusal to maintain body weight (BMI <=17.5) Intense fear of weight gain Disturbance of body image Denial of seriousness of low weight Amenorrhoea
What is subclincal anorexia nervosa?
Not all diagnostic criteria met = more prevalent, may be precursor to complete syndrome
What is the mortality of anorexia nervosa?
Highest mortality of any psychiatric condition = 5% per decade
What are some common co-morbidities of anorexia nervosa?
Anxiety, depression, OCD, alcohol misuse
What are some of the behaviours seen in anorexia nervosa?
Food restriction, over-exercising, obsession with self-weighing, misuse of laxatives or diet pills, lying about eating, calorie counting
What is the genetic influence in anorexia nervosa?
10 times higher risk if first degree relative affected
Heritability may be up to 70%
What are some general complications of anorexia nervosa?
Hypokalaemia, hyponatraemia, dehydration and rebound water retention, oedema, enlarged parotid glands, indigestion, bloating, constipation, delayed gastric emptying
What are some CV and CNS complications of anorexia nervosa?
CV = low heart rate and BP, prolonged QTc interval, arrhythmia, cardiac arrest CNS = peripheral paraesthesiae, tetany, seizures, reduced grey matter, enlarged ventricular spaces
What are some of the MSK complications of anorexia nervosa?
Muscle wasting, weakness, osteopenia, dry skin, lanugo hair, poor peripheral circulation, hair loss
What are some haematological complications of anorexia nervosa?
Raised LFTs, low WBC, anaemia, bone marrow suppression, thrombocytopenia
How does anorexia nervosa affect people psychologically?
Low mood, anxiety, irritability, narrowed range of interests, rigid thinking, social withdrawl, poor concentration, impaired decision making, drowsiness
What are the treatment options for anorexia nervosa?
Family based therapy, cognitive behaviour therapy, interpersonal therapy, specialist supportive clinical management, medication
How is family based therapy used to treat anorexia nervosa?
1st line in children and teens = parents guided to appropriately feed child calmly but persistently
How is cognitive behaviour therapy used to treat anorexia nervosa?
Focuses on recognising unhelpful thoughts about eating then challenging them and learning healthier ways of thinking
What is the focus of interpersonal therapy?
Various roles that different relationships have in someone’s life and how they can be used in a more supportive way
What is specialist supportive clinical management of anorexia nervosa?
Combines clinical management with supportive therapeutic style = aims to get patients to make a link between their symptoms and their eating behaviour
What medications are used in anorexia nervosa treatment?
Calcium and vitamin D supplement for bone thinning
Oestrogen patches for amenorrhoea
Antidepressants for low mood
What are the symptoms of bulimia nervosa?
Recurrent binges associated with compensatory behaviours = vomiting, excessive exercise, fasting
Pre-occupation with body shape and weight
What is a binge?
Consumption of unusually large amounts of food within a short interval associated with loss of control
How often do binges need to occur to diagnose bulimia nervosa?
At least once a week for three months
What is Russel’s sign?
Calluses on back of hand from self inducing vomiting = seen in bulimia nervosa and sometimes anorexia nervosa
What are associated conditions of bulimia nervosa?
Usually have co-morbid depression an dental caries
Risk of oesophageal or gastric rupture = can be fatal
What are the treatment options for bulimia nervosa?
Individual and group cognitive behaviour therapy
High dose fluoxetine may reduce food cravings
What is binge eating disorder?
Recurrent binging at least once a week for 3 months without the use of compensatory behaviours
What is the criteria for diagnosing binge eating disorder?
At least 3 of = eating more rapidly than normal, eating until uncomfortably full, eating large amounts when not hungry, eating alone because of embarrassment over how much they eat, feeling disgusted/depressed/guilty over eating
What is avoidant restrictive food intake disorder (ARFID)?
Restrictive eating pattern with persistent failure to meet appropriate nutritional needs
What are some features of avoidant restrictive food intake disorder (ARFID)?
Patient may or not be underweight
May have co-existing autism
May be related to sensory issues rather than body image concerns
What is diabulimia?
Patient with diabetes, typically type 1, restricts insulin to lose weight = chronically very raised blood sugar, may have repeated episodes of ketoacidosis
What is bigarexia/megarexia?
Muscle dysmorphia in male body builders = obsession with building muscle, see themselves as too small, may abuse anabolic steroids
What is orthorexia?
Unhealthy obsession with eating healthy food = doesn’t necessary lead to malnutrition, focus on eating pure unadulterated food
What causes refeeding syndrome?
Hormonal and metabolic changes caused by rapid refeeding
What mechanisms underlie refeeding syndrome?
Increase in blood glucose increases insulin secretion
Insulin stimulates fat, protein and glycogen secretion = this lowers already depleted serum magnesium, phosphate and potassium
What are the symptoms of refeeding syndrome?
Oedema, acute gastric dilation, cardiac abnormalities, delerium, respiratory failure, status epilepticus, suppression of haematological system
What are some features of the oedema that occurs in refeeding syndrome?
May lead to weight gain of up to 1kg per day
May be due prolonged period of diuretic abuse
Resolves spontaneously but may take several weeks
What is acute gastric dilation?
Rare but potentially life threatening = vomiting with abdominal pain and distension, responds to NG aspiration and IV feeding if recognised early
How often should electrolytes be monitored to prevent refeeding syndrome?
Once daily for one week and at least three times daily the following week
Should electrolyte supplements be given to prevent refeeding syndrome?
Yes = unless blood levels high before refeeding
What vitamin supplementation should be started before refeeding commences?
Thiamine = 200-300mg daily orally
Vitamin B = 1-2 high potency tablets
Multivitamin once daily
How should refeeding be carried out in a patient at high risk of refeeding syndrome?
Start slowly and increase over 4-7 days
