overview of obesity Flashcards
what is obesity?
disease process characterised by excessive body fat accumulation with multiple organ-specific consequences
what is the NICE definition of BMI boundaries?
- 18.5-24.9 = healthy weight
- 25-29.9 = overweight
- 30-34.9 = obesity I
- 35-39.9 = obesity II
- 40 + = obesity III
what are the caveats with BMI?
- muscular people — overestimate
- south asian populations — higher risk
- older people — lower risk
- children have special charts
what affects risk factors for heart disease and type 2 diabetes?
body weight distribution
gynaecoid vs android body weight distribution
- gynaecoid = lower fat obesity — pear-shaped
- android = upper fat obesity — apple-shaped
in the UK, what % of adults are overweight or obese?
63%
raised BMI significantly increases risk of what?
non-communicable diseases:
- CVD, diabetes, MSK disorders, some cancers, respiratory problems, reproductive function, hypertension
- children who are obese can experience breathing difficulties, hypertension, insulin resistance
AS BMI INCREASES, RISK INCREASES
what are the psychological consequences of being overweight and obese?
stress —> increased eating, increased cortisol —> weight gain —> weight based stigma —> stress etc etc
what are the 4 tiers of behaviour change conversations?
- tier 1 = universal interventions at a population level eg. sugar tax, media campaigns
- tier 2 = behavioural intervention at community level eg. primary care, schools
- tier 3 = specialist services - specialist weight management service
- tier 4 = surgery — bariatric surgery
what can be used to assess obesity in adults?
- BMI = “practical assessment of adiposity”
- waist circumference
what are centile charts?
used to measure obesity in children
how does orlistat work?
lipase inhibitor — reduces teh absorption of dietary fat. works by inhibiting gastric and pancreatic lipases, which break down triglycerides in the intestine. the TG therefore do not break down to fatty acids, to be absorbed into the blood stream. they are then excreted in the faeces
what are common side effects of orlistat?
abdominal pain and diarrhoea — may be minimised be reduced fat intake
orlistat is only for who?
for patients with BMI > 30 or BMI 28 with risk factors
when should you only continue orlistat > 3 months?
if 5% or more weight loss
what is saxenda and how does it work?
GLP-1 agonist
GLP-1 is a hormone that has different roles. One role is to regulate appetite. GLP-1 is released when food is ingested. The GLP-1 travels to and works at the hypothalamus.
Saxenda is a GLP-1 analogue, and works by interacting with neurones involved in the regulation of appetite in the hypothalamus. This decreases the feeling of hunger, causing patients to eat less and thus lose weight.
when should saxenda be offered?
only in tier 3 weight management clinics
saxenda should only be continued if there is a __% reduction in weight after __ weeks
- 5%
- 12 weeks
saxenda is licensed as an adjunct for who?
those with BMI 30 or above or BMI 27 or above, with risk factors, along with a low calorie diet and increased physical activity
what is excess weight?
any weight that takes you over a BMI of 25
what is a gastric balloon?
a temporary procedure which involves a gastric balloon being inserted using a gastroscope for 6-12 months — see 1.5-2 stone of weight loss
what is a gastric band?
adjustable inflatable device which forms a ring around the top of the stomach - works by restricting the amount of food that can pass into the stomach
people can expect to lose what % of their excess weight with a gastric band?
50%
what’s a gastric sleeve?
a procedure which involves removing the greater curve of the stomach (up to 80%) — left with small narrow tube and the antrum — extremely powerful procedure — results in 70-75% excess weight lost
what is a gastric bypass?
involves physically creating a pouch out of the top of the stomach and then reattaching the bowel so that is bypasses the rest of the stomach and the first pass of the bowel
most invasive
gold standard - compare everything else to this
can loose up to 80% of excess weight on average
what is gynecoid obesity encouraged by?
oestrogen and progesterone
why is android obesity associated with?
- heart disease and T2D
- abdominal fat is released right into the liver
- enouraged by testosterone and excessive alcohol
which poses more of a risk - lower fat obesity or upper fat obesity?
upper fat obesity = android
