Physiology of Appetite and Weight Flashcards
What is metabolic syndrome?
A group of symptoms/signs associated with high risk of CV disease.
Insulin resistance is the underlying factor
Can be associated with
- Central (visceral) fat
- Body mass index > 30
- Dyslipidaemia
- Hyperglycaemia
- Hypertension
Polycystic ovarian syndrome
-symptoms
- Oligomenorrhoea, hirsutism, acne
- Subfertility
- Endometrial hyperplasia
- Insulin resistance
Genetic Causes of Obesity
Rare
Prader-Willi
Bardet-Biedl
-common
polygenic, Susceptibility genes
Heritability of weight ~ heritability of height
Endocrinological causes of obesity
Hypothyroidism
Cushing’s syndrome
Rapid-acting peptides that regulate meal sizes
CCK, Ghrelin, PYY
Act via hypothalamus
Slow-acting hormones that regulate body weight
LEPTIN
INSULIN
Effects of obesity on the resp system
Obstructive sleep apnoea
Hypoxia / hypercapnia
Pulmonary hypertension-Right heart failure
Daytime accidents
Why is there a high risk of cancer in obese pts?
Due to
- increase in insulin, IGF-1, oestrogen
- Increase in adiocytokines
- Reflux
Leptin deficiency=
obesity
Orlistat
lipase inhibitor
MOA: Binds & inhibits lipases in the lumen of the gut
Prevents the hydrolysis of dietary fat into absorbable free fatty acids / glycerol
Excrete ~ 1/3rd dietary fat
Adverse effects: decreases absorption of vits&mins, flatulence, diarrhoea
First line agent for overweight/obese pts
Metformin (class-biguanides)
Surgical Treatment of obesity
-Laparoscopic adjustable banding
Restrictive only
make stomach smaller
Inject / withdraw saline to adjust the diameter of the band
Surgical Treatment of obesity
-Roux-en-Y gastric bypass
Restrictive and
Malabsorptive
Alterations in gut hormones and bile acid flow contribute to weight loss
can change gut microbiome
can increase satiety
Adverse effects of surgical treatments for obesity
Perioperative morbidity/mortality
Micronutrient deficiencies
Dumping Syndrome
What is the expected weight loss from lifestyle interventions
5 to 10%
