Obesity Flashcards
What is obesity?
A condition of abnormal or excessive fat accumulation in adipose tissue, to the extent that health is impaired
What BMI is considered clinically obese?
> 30
Is obesity genetic?
- around 60-70%
- Identical twins tend to have similar BMIs, irrelevant of environment
- polygenomic
Mechanism of appetite?
- leptin (body fat)
- insulin (pancreas)
- hypothalamus
What is the most common gene associated with obesity?
MC4R
What social/environmental factors affect the risk of obesity?
- ability to play outside
- car use
- screen time
- education level / achievement
- poverty
- social deprivation
What drives obesity?
The environment either heightens or reduces the impact of genetics on the risk of obesity
What co-morbidities are associated with obesity?
- depression
- sleep apnoea
- stroke
- myocardial infarction
- hypertension
- diabetes
- peripheral vascular disease
- gout
- osteoarthritis
- bowel cancer
- infertility
- gallbladder disease
Impact of obesity of cancer?
Incidence of cancers increases in those with obesity
What does an BMI above 35 mean for your life expectancy?
2 x the risk of death of those of a healthy BMI
Only effective example of reduction in obesity at a national level?
- economy collapse, fuel and food shortages
How do we treat obesity?
- determine degree of obesity
- assess lifestyle, co-morbidities and willingness to change
- management, lifestyle changes, drug treatment
- consider referral to specialist
- possibly: bariatric surgery
Why do weight rebounds happen?
Hypothalamus thinks: starvation, therefore encourages you to regain +more (increases appetite)
What does leptin deficient mean?
- insatiable hunger
- body is in survival mode, irrelevant of what is seen in the mirror
- almost impossible to lose weight
- infertility
- stunted linear growth
- decreased body temperature
- decreased energy expenditure
- decreased immune function
How to address health issues caused by diabetes?
- identify how difficult losing weight is
What is the impact of visceral fat?
- Visceral fat (fat at the waist), feeds the most into co-morbidities
- worse in men
What dietary recommendations should be made?
- 3 portions of fruit+veg (minimum)
- more fruit+veg the better
What drugs are used to treat obesity?
- Orlistat
- Gastric and pancreatic lipase inhibitor
- prevents fat absorption by 30%
- less than 3% change in weight
- low adherence (due to uncomfortable side effects)
(have to be safe, because used as a preventative measure)
-GLP1 agonists
What about Bariatric surgery?
criteria
BMI>40 BMI35-40 and other comorbidities BMI30-34.9 (T2DM) BMI>50 : first line option - non-surgical failed to achieve/maintain clinically beneficial weight-loss (at least 6 months) - receive intensive specialist treatment - fit for anaesthesia and surgery - commit to long-term follow up
What are the 3 types of Bariatric surgery?
- Gastric Bypass
- Gastric Band
- Sleeve Gastrectomy
What is the effectiveness of Bariatric surgery?
- most effective: Gastric Bypass (25% body weight - long term)
- least effective: Gastric Band
Impact of treatment of leptin deficiency?
- puberty
- increased educational treatment
- lose weight
Risks of bariatric surgery?
- risk of gambling
- risk of risky sex
What is the process of a Gastric Bypass surgery?
the top part of the stomach is joined to the small intestine, feel fuller faster, less calories consumed
