8. Eating Disorders Flashcards
DSM-5 diagnostic criteria for Anorexia Nervosa
- Restriction of input relative to exact requirements leading to significantly low body weight
- Marked and excessive fear of putting on weight/becoming fat: repetitive behaviours to prevent weight gain
- Distortions in self-perception of body weight/shape associated with lack of recognition of serious consequences of current low body weight
Subtypes of Anorexia Nervosa
Restricting: weight loss over the last 3 months achieved mainly by means of dieting, fasting or excessive exercise
Binge-eating/Purging: recurrent episodes of binge-eating or purging behaviours over the last 3 months
Management for AN
Pharmaco (no drugs proven effective):
- Fluoxetine (improvement in mood)
- Mirtazapine (can promote weight gain)
Non-pharmo:
- CBT
- Interpersonal psychotherapy
- AN focused family therapy
Reasonable target weight gain
Increment of 0.5-1kg per week
Poor prognostic factors in Anorexia Nervosa
- Relatively late age of onset
- Presence of severe vomiting and weight loss
- Dysfunctional family
- Extreme treatment avoidance
- Longer duration of illness
- Personality disorder
- Male gender
- Very low BMI
Favourable prognostic factors in Anorexia Nervosa
- Early onset
- Absence of severe weight loss and serious medical conditions
- Supportive family
- Good motivation to change
Necessary investigations for AN patients
FBC, LFT, RP, electrolytes, hormone profiles, fasting venous glucose, ECG, EEG
Cognitive assessment and further risk assessment
Refeeding syndrome symptoms
Dependent edema, aches and pains
Electrolyte deficiencies
Cardiac decompensation (CHF)
DSM-5 diagnostic criteria for Bulimia Nervosa
- Recurrent episodes of binge eating: lack of control and eat till excessively full
- Repetitive compensatory behaviour: self-induced vomiting, usage of laxatives
- Duration: at least once a week for 3 months
- Self-esteem
What is Russell’s sign?
Abrasions over dorsal part of the hand (interphalangeal joints) because fingers are used to induce vomiting
- more commonly seen in BN
Management of Bulimia nervosa
Pharmaco:
- Antidepressant: Fluoxetine (improvement in mood)
- Mood stabilisers
Non-pharmo:
- CBT
- Interpersonal psychotherapy
Note that in AN the BMI is very very low while in BN the BMI can be normal or high
-
Indications to hospitalisation for anorexia nervosa
- BMI < 15kg/m^2
- Bradycardia < 40bpm
- Failure of outpatient treatment
- High self-harm/suicide risk
Reason for parotid gland swelling in Bulimia nervosa
Frequent self-induced vomiting in BN leads to reflux of gastric acid and causes inflammation in the parotid gland
Laxative use can cause
metabolic acidosis
Repeated vomiting can cause
Hypokalemic, hypochloremic metabolic alkalosis
Objective signs to establish diagnosis of AN
Low BMI
Amenorrhea
Physical findings in patient with AN
Low weight, bradycardia, hypotension, amenorrhea, breast atrophy, muscle weakness, peripheral neuropathy, increase in body hair (lanugo hair), dry skin, alopecia
Electrolyte abnormalities in Anorexia nervosa
- Low Ca2+
- Low Mg2+
- Low PO4
- Low Na+
- Low K+
- High amylase
- Low albumin
- Low glucose
- Low insulin
- High lipid
- Metab acidosis (diarrhoea)
- Metab alkalosis (vomiting)
Hormonal changes in anorexia nervosa
- Low oestrogen
- Low testosterone
- Low T4/T3
- Low FSH/LH
- High cortisol
- High growth hormone
What is considered purging?
Self induced vomiting
Excessive use of laxatives
Excessive use of diuretic
Excessive use of enema
(purging: evacuation of GI or urinary system hence excessive exercise is not considered purging)
Factors influencing prognosis for bulimia nervosa
● Good
- Ability to engage in treatment
- Motivation for change
● Bad
- Childhood obesity
- Low self esteem
- Associated personality disorder
- Substance abuse
What happens if lots of nutritional supplement is given to an ED patient
Refeeding syndrome
What happens during refeeding syndrome?
Worsens electrolyte deficiencies:
- Hypophosphotemia
- Hypokalaemia
- Hypomagnesemia
Seizures
Congestive heart failure
Peripheral oedema
Respiratory insufficiency
Aches and pains
Rhabdomyolysis
Haemolysis
*During early stages of refeeding, a resting heart rate of >70bpm may suggest heart failure and refeeding syndrome
Severity markers based on BMI
Mild: >17
Moderate: 16-16.9
Severe: 15-15.9
Extreme: <15
Signs of repeated self-induced vomiting
- Russell’s sign
- Parotid gland enlargement
- Erosion of tooth enamel
- Dental caries
Hallmark manifestation of refeeding syndrome
Hypophosphatemia
Which antiD should be avoided for patients with eating disorder and why?
Bupropion
- higher incidence of seizures
- weight loss
Binge Eating Disorder
Characterised primarily by episodes of recurrent binge eating episodes without compensatory purging behaviours. It was a/w 3 or more of the following:
- Eating rapidly until uncomfortably full
- Eating large amounts despite lack of hunger
- Eating in solitude to avoid embarrassment
- Feelings of disgust or guilt following the episode
