Obesity Flashcards
Obesity
A condition of abnormal or excessive fat accumulation in adipose tissue to rhe extent that health is impaired
BMI benchmarks
18.5 or less underweight
18.5 - 25 normal
25 - 30 overweight
30 - 35 obese
35+ severely obese
Issue with bmi
Doesn’t take into account body composition
What causes obesity
Mix of genetic and environmental/behavxioiral factors
examples of driving environmental factors?
less access to outdoor space, car use, screen time, lower education, poverty, social deprivation = positive correlation with obesity
global incidence patterns?
occurs worldwide, almost 2 billion adults worldwide overweight and 650 million + obese
what comorbidities is obesity associated with?
depression, stroke, MI, hypertension, diabetes, bowel cancer, osteoarthritis, peripheral vascular disease etc
BMI affect on mortality
Higher bmi correlated with higher mortality
how is obesity treated?
diet and lifestyle changes, consider drugs or surgery with increasing degrees of severity
what should diet aim for?
enough portions of fruit and veg, good balance between nutrient types
what does leptin deficiency cause?
infertility, stunted growth, decreased {body temp, immune function, energy expenditure}
what does leptin do?
Regulates appetite
Regulates synthesis of thyroid hormones,insulin secretions,bone mass,menstrual cycle,increases heart rate and activates immune cells
Effect of leptin administration in deficient children
Weight goes down and LH pulsatility restored
who else can leptin be administered to for a therapeutic effect?
restores LH pulsatility in women with amenorrhea
what is the principle of leptin resistance?
high leptin doesn’t have more effect (inhibit appetite) than lower presence of leptin as it is an anti starvation hormone not anti obesity so presence shows CNS that system has sufficient fat reserves
Absence can cause hyperphagia,lowered energy expenditure and sterility
what is orlistat?
gastric and pancreatic lipase inhibitor → reduces dietary fat absorption
Produced by streptomyces toxytricini
Side effects of orlistat
Fatty stools,faecal urgency and incontinece
Fat soluble vitamin deficiency
Effects of GLP-1
- generalbody weight down, BP down, plasma glucose down, plasma lipids down
- pancreaticinsulin up, glucagon down
- brainappetite down, satiety up
- heartcontractility up, glucose uptake down
- vesselsendothelial function up, stiffness and inflammation down
- kidneyssodium excretion and diuresis up
- liverliver fat down, inflammation down, insulin resistance down
- GLP-1 receptor agonist
What is liraglutide/saxenda
GLP-1 agonist which is long acting
Daily injection
Double dose used for type 2 diabetes
when should bariatric surgery be considered?
40+ BMI / 35+ with comorbidities / 30-35 with newly diagnosed type II DM
First line for BMI>50
Common types of bariatric surgery
- gastric bypasstop part of stomach connected to small intestine
- gastric bandadjustable tightness band to restrict stomach
- sleeve gastrectomyremove portion of stomach
how effective is bariatric surgery?
requires commitment to long term follow up, maybe some reduction in mortality and weight loss long term but questionable
other examples of long-acting GLP-1 receptor agonists?
tirzepatide, semaglutide
what is given in combination with semaglutide
cagrilintide
Long acting amylin analogue
what is retatrutide?
triple agonist → glucose-dependent insulinotropic polypeptide, GLP-1, glucagon receptors
how effective are drugs against obesity?
Previously ineffective new gen might be effective
Tirzepatide
Long acting GLP1 receptor and glucose dependant insulinotrophic polypeptide receptor co agonist causes 20-22 body weight loss
Cagrilintide
Long acting amylin analogue given with semaglutide
Causes nausea but significant weight loss
