Anti-hyperlipidaemics - Statins Flashcards
Cholesterol is often judged as being all bad. However, there are a number of benefits of cholesterol. Which of the following is NOT one of these benefits?
1 - part of lipid membranes
2 - component of bile
3 - synthesise coagulation factors
4 - steroid synthesis
5 - vitamin D
3 - synthesise coagulation factors
- we need cholesterol in our skins cells to make vitamin D from sunlight.
The liver is able to synthesis cholesterol, or we can consume it in out diets. Once fats and cholesterol have been digested and absorbed they are transported around the body in lipoproteins (contain phospholipids and proteins tags) as they are hydrophobic. As part of the exogenous pathway, what is the 1st lipoprotein they are packaged in?
1 - chylomicrons
2 - LDL
3 - HDL
4 - VLDL
1 - chylomicrons
- largest lipoprotein
- least dense lipoprotein (essentially they are large and not full, so not dense)
- uses the portal vein for this
Once lipids and cholesterol have been packaged into chylomicrons, do they enter the circulatory system or lymphatics?
- lymphatics
- they then enter the circulation at the subclavian vein
- they can then travel to the liver and adipose tissue
The liver is able to synthesis cholesterol using the mevalonate pathway. What is the rate limiting step in this pathway, that ultimately determines cholesterol synthesis?
1 - fatty acid synthase
2 - 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase
3 - HMG-CoA synthase
4 - acetyl-coA carboxylase
2 - 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase
- this enzyme creates mevalonate, which is the precursor of cholesterol
Once cholesterol has been synthesised in the liver, it is once again packed up into lipoproteins and sent off into the circulation to carry TAGs to the rest of the body as part of the endogenous. Which type of lipoprotein is used 1st?
1 - chylomicrons
2 - LDL
3 - HDL
4 - VLDL
4 - VLDL
- low density refers to the concentration of cholesterol
- VLDL = high TAGs and low cholesterol
- LDL = low TAGs and high cholesterol
Once VLDL have been distributed around the body and distributed TAGs they become LDLs (distribute cholesterol around the body as part of the endogenous), and ultimately HDLs. What is the benefit of HDLs?
1 - remove excess TAGs from blood
2 - collect excess cholesterol and return it to the liver
3 - remove cholesterol from plaques
4 - distribute cholesterol around the body
2 - collect excess cholesterol and return it to the liver
- part of the reverse pathway
What receptor is missing in patients with Familial hypercholesterolemia, meaning they are unable to absorb cholesterol?
1 - VLDL receptors
2 - LDL receptors
3 - lipoprotein lipase receptors
4 - GPCR
2 - LDL receptors
- causes very high cholesterol
If these is a lot of LDL, the tissues taking up the cholesterol become saturated. What is a key risk of this in the endothelium of blood vessels?
1 - cause vasodilation
2 - cause damage to endothelium and initiate the coagulation cascade
3 - collect on endothelium and form plaques
4 - all of the above
3 - collect on endothelium and form plaques
- increase risk of strokes, MI and PVD
Which of the 2 drugs below is a anti-hyperlipidaemic statins that we need to be aware of?
1 - Simvastatin
2 - Bisoprolol
3 - Ramipril
4 - Atorvastatin
1 - Simvastatin
4 - Atorvastatin
Simvastatin and Atorvastatin are anti-hyperlipidaemics statins. What is the mechanism of action of both of these drugs?
1 - inhibit lipid absorption in the GIT
2 - inhibit HMG-CoA reductase
3 - activates lipoprotein lipase
4 - inhibit HMG-CoA synthase
2 - inhibit HMG-CoA reductase
- less cholesterol is available, so hepatocytes take up LDL from blood to make more cholesterol
- reduces LDL
- reduces cholesterol
- reduces TAG
- increased HDL
Simvastatin and Atorvastatin are the 2 core anti-hyperlipidaemics that we need to be aware of. Which of the following is NOT an effect of these medications?
1 - reduced cholesterol
2 - reduced LDL
3 - total cholesterol
4 - reduced blood glucose
5 - triglycerides
6 - increased HDL
4 - reduced blood glucose
Which of the following is NOT an indication of anti-hyperlipidaemics statins?
1 - primary prevention of adverse cardiovascular (CV) event
2 - dyslipidaemia
3 - hypertension
4 - secondary prevention of adverse cardiovascular (CV) event
3 - hypertension
- secondary CV relates to those with IHD, PVD or previous strokes
Anti-hyperlipidaemics statins, atorvastain and simvastatin are indicated in the primary prevention of adverse cardiovascular (CV) event. This relates to individuals >40 y/o who have not had a CV event, but are at risk of having one (stroke, MI etc..). Using a validated scoring tool such as the Q-risk, what is the 10 year cut off risk to begin using statins?
1 - >1%
2 - >10%
3 - >20%
4 - >40%
2 - >10%
There are 3 common adverse events of statin use. Which of the following is NOT a common adverse event?
1 - headache
2 - rhabdomyolysis
3 - GI upset
4 - muscle aches
2 - rhabdomyolysis
- can occur but this is rare
Although rare, which 2 of the following can statins cause in the liver?
1 - NAFLD
2 - fibrosis
3 - drug induced hepatitis
4 - increased liver enzymes
3 - drug induced hepatitis
4 - increased liver enzymes