Eating Disorders Flashcards
Define anorexia nervosa
Eating disorder characterised by deliberate weight loss, an intense fear of fatness, distorted body image and endocrine disturbances
Predisposing factors for anorexia nervosa
Biological - genetic - fhx - female - early menarche Psychological - sexual abuse - preoccupation with slimness - dieting behaviours starting in adolescence - low self-esteem - premorbid anxiety or depressive disorder - perfectionism, obsessional/anankastic personality Social - western society - pressure to diet in a society that emphasises being thin - bullying revolving around weight - stressful life events
Precipitating factors for anorexia nervosa
Biological
- adolescence and puberty
Psychological
- criticism regarding eating, body shape or weight
Social
- occupational or recreational pressure to be slim - ballet, models
Perpetuating factors for anorexia nervosa
Biological - starvation leads to neuroendocrine changes that perpetuate anorexia Psychological - perfectionism Social - occupation - western society
ICD-10 criteria for the diagnosis of anorexia nervosa
Fear of weight gain
Endocrine disturbances - amenorrhoea, loss of sexual interest and potency
Emaciated - abnormally low body weight < 17.5
Deliberate weight loss
Distorted body image
Present for at least 3 months and absence of
- recurrent episodes of binge eating
- preoccupation with eating/craving to eat
Differential diagnosis of anorexia nervosa
Bulimia nervosa Eating disorder not otherwise specified Depression OCD Schizophrenia Organic causes of low weight - diabetes, hyperthyroidism, malignancy Alcohol or substance misuse
Complications of anorexia nervosa
Metabolic
- hypokalaemia, hypercholesterolaemia, hypoglycaemia, impaired glucose tolerance, deranged LFTs, increased urea and creatinine, low potassium, low phosphate, low magnesium, low albumin, low chloride
Endocrine
- increased cortisol, increased growth hormone, reduced T3/4, reduced LH, FSH, oestrogen and progestogens leading to amenorrhoea, reduced testosterone
GI
- enlarged salivary glands, pancreatitis, constipation, peptic ulcers, hepatitis
CVS
- cardiac failure, ECG abnormalities, arrhythmias, reduced BP, bradycardia, peripheral oedema
Renal
- renal failure, renal stones
Neuro
- seizures, peripheral neuropathy, autonomic dysfunction
Haem
- iron deficiency anaemia, thrombocytopenia, leukopenia
MSK
- proximal myopathy, osteoporosis
Others
- hypothermia, dry skin, brittle nails, lanugo hair, infections, suicide
Features of binge eating disorder
Recurrent episodes of binge eating without compensatory behaviour such as vomiting, fasting or excessive exercise
Features of EDNOS or atypical eating disorder
Closely resembles other eating disorder but does not meet diagnostic criteria
Management of anorexia nervosa
Aim for 0.5-1kg/ week weight gain for inpatient and 0.5kg/week outpatient Biological - treatment of medical complications - SSRIs - for comorbid depression or OCD Psychological - psycho-education about nutrition - CBT - cognitive analytic therapy - interpersonal psychotherapy - family therapy Social - voluntary organisations - self help groups
Criteria for hospitalisation for anorexia nervosa
Medical - BMI < 14 - severe electrolyte abnormalities Psych - suicidal ideation
Features of refeeding syndrome
Potentially life-threatening syndrome that results from food intake after prolonged starvation or malnourishment due to changes in phosphate, magnesium and potassium
- occurs due to insulin surge
Features of refeeding syndrome
Hypokalaemia Hypomagnesaemia Hypophosphatemia Abnormal glucose metabolism Cardiac failure
Define bulimia nervosa
Eating disorder characterised by repeated episodes of uncontrolled binge eating followed by compensatory weight loss behaviours and overvalued ideas regarding body shape/weight
Aetiology of bulimia nervosa
Sense of compulsion to eat
Binge eating
Fear of fatness
Compensatory weight loss behaviours
Predisposing factors for bulimia nervosa
Biological - female sex - fhx - early onset of puberty - type 1 diabetes - childhood obesity Psychological - physical or sexual abuse - childhood bullying - parental obesity - pre-morbid mental health disorder - preoccupation with slimness - parents with high expectations - low self-esteem Social - living in a developed country - profession - difficulty resolving conflicts
Precipitating factors for bulimia nervosa
Biological - early onset puberty/menarche Psychological - perceived pressure to be thing may come from culture - criticism regarding body weight or shape Social - environmental stressors - family dieting
Perpetuating factors for bulimia nervosa
Biological - co-morbid mental health problems Psychological - low self-esteem - perfectionism - obsessional personality Social - environmental stressors
ICD-10 criteria for diagnosis of bulimia nervosa
Behaviours to prevent weight gain
- self-induced vomiting, alternating periods of starvation, drugs (laxatives, diuretics, appetite suppressants), excessive exercise
Preoccupation with eating
- sense of compulsion which leads to binging
Fear of fatness
- self-perception of being too fat
Overeating
- at least 2 episodes per week over a period of 3 months
Subtypes of bulimia nervosa
Purging
- patient uses self-induced vomiting and other ways of expelling food from body
Non-purging
- patients use excessive exercise or fasting after binge
Complications of repeated vomiting
CVS
- arrhythmias, mitral valve prolapse, peripheral oedema
GI
- mallory-weiss tears, increased salivary glands
Metabolic/Renal
- dehydration, hypokalaemia, renal stones, renal failure
Dental
- permanent erosion of dental enamel secondary to vomiting of gastric acid
Endocrine
- amenorrhea, irregular menses, hypoglycaemia, osteopenia
Derm
- Russel’s sign - calluses on back of hand due to abrasion against teeth
Pulmonary
- aspiration pneumonitis
Neuro
- cognitive impairment, peripheral neuropathy, seizures
Management of bulimia nervosa
Biological - trial of antidepressants - fluoxetine - medical complications Psychological - psychoeducation about nutrition - CBT - interpersonal psychotherapy Social - food dietary to monitor patterns - techniques to avoid binging - small, regular meals - self-help programmes
