Eating Disorders Flashcards
Who does eating disorders usually affect?
Perfectionist, high achieving young women with low self-esteem.
Co-morbid with other MH disorders e.g. depression
When does dieting become an eating disorder?
When thinness becomes an all consuming pursuit
What is Anorexia Nervosa?
Involves weight loss methods causing extreme emaciation
Prevalence- 0-6%
Onset is usually in girls aged 16-22 and affects all social classes
What is Bulimia Nervosa?
Involves binge eating followed by vomiting
Prevalence- 1%
BN is more common than AN, however BN is probably largely undetected since patients are usually as secretive as in AN, but are not as obviously emaciated.
BN usually starts in mid-adolescence.
What is a Binge eating disorder?
Bulimia nervosa without purging
Prevalence- 2.8%
Aetiology
Genetic Psychological theories Socio-cultural Personal History Family
Genetic causes?
- In AN, heritability is about 58%.
- MZ:DZ twin concordance rates are 65:32.
- Genes are less salient in BN.
Psychological theories causes?
- Perfectionism and low self-esteem are risk factors for both AN and BN.
- Theories for AN include the idea that successful weight loss enhances the patient’s sense of achievement, autonomy and perfectionism.
When life feels uncontrollable, AN comforts by providing the ability to control something (weight).
The disorder can also be seen as a way of avoiding separation from family or becoming an independent sexual being (it maintains dependency on close family and a peri-pubertal physique).
Socio-cultural causes?
•Social pressures to be thin and the promotion of dieting are important influences on the development of both AN and BN.
•High risk groups include occupations where emphasis is on weight or body image (models, athletes and dancers).
western society
Personal History causes?
- People with BN often have a history of obesity and up to 50% have previously suffered from AN (the reverse pattern occurs less frequently).
- Experiences of child abuse are commonly found in AN and BN, but no more so than in other psychiatric illness.
Family causes?
- Parental overprotection and family enmeshment are associated with AN.
- Enmeshment describes relationships that are over-involved, with poor boundaries making it difficult for members to feel independent.
- BN is connected with disturbed family dynamics, parental weight concern and high parental expectation.
- FHx of obesity, depression or substance misuse are also risk factors.
The 4 main diagnostic points for Anorexia Nervosa?
ICD10
- BM1 <17.5/ 15% less than expected
- Deliberate weight loss e.g. calorie counting, laxatives, excessive exercise, appetite suppressants
- Distorted Body image
- Endocrine dysfunction- HPG axis affected causing amenorrhea, impotence, loss of libido. (if began before puberty menarche and breasts affected)
General physical complications? (6)
- Lethargy
- Cold intolerance
- Pancytopenia (severe anorexia)
- Anaemia, leuocpenia, thrombocytopenia
- Infections
- Dental caries
Cardiovascular complications? (7)
- Bradycardia
- Hypotension (postural drop)
- Arrhythmia’s (secondary to hypokalaemia)
- Mitral valve dysfunction
- Cardiac failure
- Sudden death
- Prolonged QT
Over 80% will have CV complications
GI complications? (5)
- Constipation
- Abdominal pain
- Ulcers, Oesophageal tears
- Delayed gastric emptying- makes patient feel bloated even after small amounts
- Nutritional hepatitis occurs in a third of patients, detected by low serum protein with raised bilirubin, raised LDH and raised alkaline phosphatase.
Reproductive complications? (4)
- Amenorrhea
- Infertility- due to atrophy of ovaries and testicles
- Loss of libido
- Low birth weight infant
MSK complications? (2)
- Osteoporosis- fractures
2. Proximal myopathy
Neurological complications? (4)
- Peripheral Neuropathy
- Delirium
- Seizures
- Loss of brain volume (ventricular enlargement, sulcal widening, cerebral psuedoatrophy that will return
to normal once normal eating habits resume)
Dermatological complications? (3)
- Brittle hair
- Dry scaly skin
- Laguno hair- fine hair that usually grows on a foetus in the womb
What is the purpose of the laguno hair?
It is the bodies attempt to keep warm following body fat loss
What can occur after binging to the glands in the body?
Swollen parotid and submandibular glands
Differentials for AN?
- Medical causes e.g. Hyperthyroidism, malignancy, Addison’s, AIDS
- Depression
- Bulimia Nervosa
- Eating disorder not otherwise specifies (EDNOS)- atypical presentations
- Body dysmorphic disorder (weight loss would not be deliberate)
- Psychosis (if food is believed to be poisoned leading to weight loss)
Investigations for AN?
- Height, weight, BMI
- Squat test: ask pt to squat down and rise to standing without using their arms (difficult with proximal myopathy).
- Sit up test
- Essential blood tests:
ESR, TFTs (exclude most organic causes of weight loss). ESR is normal or low in anorexia.
FBC, U&E, phosphate, albumin, LFT, creatinine kinase, glucose (evaluate nutritional state and risk). - ECG: bradycardia, arrhythmias and a prolonged QT interval.
- Other tests as indicated (DEXA scan for low bone density with 2yr history).
7.BP (check for postural hypotension)
What is Melanosis coli?
Pigmentation of the colonic mucosa as a result of laxative abuse
How do you work out BMI?
Weight (kg)/height (m squared)
Hospitalisation is indicated when BMI drops to <13.5
What type of management is recommended for AN?
A combined approach of pharmacological, psychological and education
Pharmacological management of AN?
Fluoxetine (especially if there are clear obsessional ideas regarding food)
Vitamin Supplements
Previously TCAs or chlorpromazine used for weight gain.
Psychological management of AN?
- Psychoeducation- advise on nutrition and health
- Motivational interviewing- helps to engage patients who lack insight/ hold positive views of illness
- Family therapy!! Anorexia Nervosa focused family therapy (under 18’s)
- Interpersonal therapy- help improve social functioning
- CBT- ED: address control, low self esteem and perfectionism(or if FT-AN is inappropriate/ineffective)
- Maudsley Anorexia Nervosa Treatment for Adults: 20 sessions (over 18’s)
Physical management?
Managing weight gain and also maintain a healthy weight
When in refeeding phase consider daily U&Es and ECGs until electrolytes have stabilised
Monitoring U&Es and ECGs
Oral supplementation for electrolyte imbalances
Bisphosphonates if diagnoses of osteopenia/osteoporosis
Advise regular dentist assessment if regularly purging
Dietician input
MDT approach where there is comorbid physical or mental illness
When is admission needed?
usually seen as outpatients but in the case of:
BMI <13 or rapid weight loss
Serious physical complications
High suicide risk
electrolyte imbalances, severe dehydration, evidence of end organ failure, bradycardia <40bpm, ECG changes, >1kg weight loss a week on 2+ weeks, significant suicide risk.
What may occur on compulsory admission?
Compulsory refeeding
‘feeding’ is deemed as treatment
should be last resort
How is compulsory feeding enabled?
MHA
Epidemiology of Bulimia Nervosa?
- More common in F (10:1 ratio)
- An increasing prevalence in Western countries
- Usually begins a little later than anorexia nervosa (16-17 for anorexia vs. late early 20s for bulimia).
- Prevalence of bulimia is 1-3% of young women.
Aetiology of BN?
- Genetic- unclear
2. Environmental- history of dieting, AN (50%), low self esteem, perfectionism, substance abuse
Clinical presentation of BN?
- Binge eating- cravings, loss of control, high calorie, compulsion to consume
- Purging- binges cause feeling of guilt resulting in measures to undo damage e.g. laxatives, vomiting, diuretics
- Body image distortion
- BMI >17.5- in contrast with AN patients with BN are normally of normal or slightly increased weight and periods are present
physical symptoms include:
- Bloating and fullness
- Lethargy
- Heartburn and reflux
- Sore throat
What is secondary to weight being normal?
Physical symptoms are usually those occurring secondary to vomiting and purging e.g. arrhythmias (hypokalaemia) or convulsions (hyponatraemia).
Diagnosis of BN?
Patients must have ALL of the ICD-10 criteria:
- Binge eating
- Methods to counteract weight gain – vomiting, laxatives, fasting, exercise, etc.
- Overvalued ideas: dread of fatness, low target weight
In order to fulfil DSM-5 binge eating should occur, on average, atleast once a week for 3 months.
Investigations for BN?
Similar to AN but particular attention to electrolytes and ECG
k+ is usuallly low
Russell’s sign – calluses form on the back of the hand, caused by repeated abrasion against teeth during inducement of vomiting
Management of BN?
- Treat medical complications.
- SSRIs: particularly fluoxetine. These can reduce binging and purging through enhancing impulse control.
- Treat comorbid psychiatric illness. Depression, self-harm and substance misuse occur frequently.
- CBT-ED: helpful in controlling symptoms. Longer term psychotherapies may be needed to address underlying and comorbid problems.
Others:
Dental review
Where are most BN patients managed?
In the community
When are BN patients admitted?
Admission only for suicidality, physical problems, extreme refractory cases, or if pregnant (↑risk of spontaneous abortion)
If they will not take food orally (usually look at there 24 hour previous food profile when making decision)
Markers of Nutritional decomposition? (9)
- BMI <13
- Weight loss >1kg per week
- Purpuric rash
- Cold peripheries
- Core body temperature <34.5
- Hypotension (SBP <80mmHg, DBP <50mmHg)
- Bradycardia (<40bpm) with prolonged QT interval on ECG.
- Inability to stand from squatting without using arms for leverage (squat test)
- Electrolyte imbalance: K+ <2.5/ Na+ ,130/ PO4 <0.5.
If there is evidence of Nutritional decomp, what must be done?
Urgent medical treatment
Why is establishing adequate food intake hazardous?
Refeeding syndrome is a recognised cause of mortality in the early stages of treatment. This is characterised by electrolyte imbalance (principally low serum phosphate, potassium and magnesium) caused by their sudden intracellular movement due to the switch from fat to carbohydrate metabolism and associated increased secretion of insulin.
Prognosis for eating disorders?
- After 10 years, 50% patients with AN have no eating disorder and 10% have died (suicide accounts for 1/3 of deaths).
- The remaining 40% patients with AN have ongoing problems and crossover to BN is common.
- The prognosis for BN is better- 70% have recovered completely and only 1% have died at 10 years.
Poor prognostic factors include
- Low birth weight
- Bulimic features
- Later onset
- Longer illness duration
What in the bloods is looked at before Refeeding syndrome? (3)
- Phosphate
- Magnesium
- Potassium
What is diabulimia?
Deliberate manipulation of insulin levels by Type 1 diabetics to control their weight
What is Orthorexia
Obsession with eating only foods that one considers healthy
What is Pica?
An appetite for substances that are not nutritious e.g. Ice (pagophagia), hair (trichophagia), paper (xylophagia), sharp objects (acuphagia)
Questions to screen for ED?
SCOFF questionnaire: screens for eating disorders
- do you make yourself Sick because you feel uncomfortably full?
- do you worry that you have lost Control over how much you eat?
- have you lost more than One stone in a 3-month period?
- Do you believe yourself to be Fat when others say you’re too thin?
- Would you say Food dominates your life?
(2+ indicate likely case of anorexia or bulimia)
Management of binge eating?
Psychological- CBT-BED, interpersonal psychotherapy
Pharmacological- SSRI
Physical- monitor weight and give support
