disorders of appetite

Question 1

define polydipsia?

Answer 1

excessive thirst

Question 2

define adipsia?

Answer 2

inappropriate lack of thirst with consequent failure to drink in order to correct hyperosmolality

Question 3

define anorexia?

Answer 3

loss of appetite for food

Question 4

define obesity

Answer 4

excess fat accumulation that presents a risk to health

Question 5

What is the name of the hormone responsible for the regulation of Osmolality?

Answer 5

ADH antidiuretic hormone

Question 6

How does ADH work and where is it stored?

Answer 6

acts on collecting ducts of kidneys to regulate the volume and osmolality of urine
when plasma ADH is low a large volume of urine is excreted
posterior pituitary

Question 7

If the plasma concentration of ADH is low will there be a water diuresis or an anti-diuresis?

Answer 7

diuresis

Question 8

Which regions are sensory osmoreceptors found in the hypothalamus?

Answer 8

Organum vasculosum of the laminate terminalis
Subfornical organ

Question 9

What is the most common disorder of thirst?

Answer 9

Secondary polydipsia

Question 10

List at least 3 causes of primary polydipsia

Answer 10

Mental illness - psychogenic polydipsia, mood disorders such as depression and anxiety, anorexia, drug use
Brain injury - trauma
Organic brain damage - central pontine myelinolysis, Alzheimer’s disease

Question 11

What is secondary polydipsia?

Answer 11

Medical issues that disrupt any step in osmoregulation or alter ADH can cause secondary polydipsia

Question 12

What are the two types of disorders of thirst?

Answer 12

Polydipsic - primary or secondary
Adipsic - primary or secondary

Question 13

What chronic medical conditions can cause secondary polydipsia?

Answer 13

Diabetes insipidus and mellitus
Acute kidney failure
Conns syndrome
Addisons disease
Sickle cell anaemia

Question 14

What medications can cause secondary polydipsia?

Answer 14

Diuretics• Laxatives- Both result in dehydration• Antidepressants

Question 15

What illnesses can cause dehydration leading to secondary polydipsia

Answer 15

Dehydration• Acute illness• Sweating• Fevers• Vomiting• Diarrhoea• Underhydration

Question 16

Why is polydipsia a problem?

Answer 16

drinking too much water can upset the electrolyte balance in the body-hyponatraemia

Question 17

What can hyponatraemia as a result of polydipsia lead to?

Answer 17

• Kidney and bone damage
• Headache
• Nausea
• Cramps
• Slow reflexes
• Slurred speech
• Low energy
• Confusion
• Seizures

Question 18

What is the mechanism of adipsia?

Answer 18

Increased osmolality of urine, leading to stimulated secretion of ADH, water retention, sensation of thirst decrease

Question 19

What are the different categorisations of adipsia?

Answer 19

Type A - most common (essential hyponatraemia)
Type B
Type C
Type D

Question 20

List some examples of eating disorders?

Answer 20

Binge eating disorder
Anorexia nervosa
Bulimia nervosa
Pica
Rumination syndrome
Avoidant/ restrictive food intake disorder

Question 21

what BMI is classed as underweight?

Answer 21

Below 18.5

Question 22

What BMI is defined as the healthy weight range?

Answer 22

18.5 - 24.9

Question 23

What BMI is classed as overweight?

Answer 23

25-29.9

Question 24

What BMI is categorised as class 1 obesity?

Answer 24

30-35

Question 25

What BMI is classed as type 2 obesity?

Answer 25

35-40

Question 26

What BMI is classed as type 3 obesity?

Answer 26

40+

Question 27

What are the signs and symptoms associated with anorexia nervosa?

Answer 27

Low BMI, continuous weight loss, amenorrhea, halitosis, mood swings, dry hair, skin & hair thinning

Question 28

What are the different possible causes of anorexia nervosa?

Answer 28

Genetic, environmental, psychological, sociological

Question 29

Q: Mr Thomas is a 45 year old with significant abdominal obesity and T2DM. Has tried dieting before without success, his BMI is 39. What therapy would you recommend?

Answer 29

Gastric bypass & sleeve gastrectomy

Question 30

List some comorbidities associated with obesity?

Answer 30

Depression Sleep apnoea Stroke MI HTN diabetes Peripheral vascular disease Gout Osteoarthritis Bowel and other cancer

Question 31

What are the treatment options for obesity?

Answer 31

Life-style modification> Diet + Exercise• Surgical treatment> gastric bypass & sleeve gastrectomy> for people with a > BMI 40 or 35+ comorbidities> WL 5 yrs after BS: 30% - 35%> reduction of all cause mortality & morbidity after BS

Question 32

What are the surgical treatments of obesity?

Answer 32

People with a > BMI 40 or 35+ comorbidities • Various procedures • Most common Roux-en-Y gastric bypass & sleeve gastrectomy • Weight loss 5 yrs after BS: 30% - 35% • Remission of comorbidities > Diabetes (80%) > OSA (80%-85%)

Question 33

What hormonal changes are often seen after bariatric surgery?

Answer 33

ghrelin reduces - reduced hunger • GLP1, GLP2 & PPY increases - increased insulin, reduced glucagon, increased satiety