Module 12 - Part 2 Flashcards
What is the first line of treatment for elevated LDL cholesterol?
Primary treatment is lifestyle changes including diet modification, weight exercise plans and change in smoking status
What are the benefits of CV exercise?
Decreasing LDL cholesterol, elevating HDL cholesterol and decreasing insulin resistance and BP
How does smoking affect cholesterol levels.
Decreases HDL and increases LDL
When is drug treatment for cholesterol levels initiated?
When target cholesterol levels are not achieved by lifestyle changes
What are the different classes of drugs used to treat elevated blood lipids?
1 - Statins 2 - Bile acid sequestrants 3 - Nicotinic acid 4 - Cholesterol absorption inhibitors 5 - Fibric acid derivates (Fibrates)
Hepatic cholesterol synthesis occurs in what pathway?
Mevalonic acid pathway
Describe the important parts of the mevalonic acid pathway.
Acetyl-CoA –> HMG CoA - HMG CoA reductase -> mevalonic acid –> several other steps –> cholesterol
What is the rate limiting step in cholesterol synthesis?
Conversion of HMG-CoA into mevalonic acid by HMG-CoA reductase
What is the mechanism of action of statins?
Statins decrease hepatic synthesis of cholesterol by inhibiting HMG-CoA reductase
This causes upregulation of hepatic LDL receptors –> more cholesterol removed from the blood –> decrease in LDL cholesterol levels in the blood
What are the physiological benefits of statins use?
1 - Decreased LDL cholesterol
2 - Increased HDL cholesterol
3 - Decreased triglycerides in the blood
What is primary prevention aimed at?
Aimed at preventing the development of CV disease
Multiple recent studies have shown that statins decrease the incidence of _______ events even in low risk patients with no history of ____.
coronary
CHD
What does secondary prevention aim to do?
Prevent the recurrence of CV events
These are among the highest prescribed drugs in the world.
In fact, _________ (_______) is the highest prescribed drug in Canada and the US, while ________ (______) is the 4th highest prescribed drug in Canada.
Statins
Atorvastatin (Lipitor) - highest prescribed
Rosuvastatin (Crestor) - 4th highest in Canada
Atorvastatin (Lipitor)
- ____ oral bioavailability
- _____ fraction of absorbed dose is extracted by the liver
- Distribution is primarily to the ______, but also to the ________, _______ _______ and ________ _______
- Metabolized by ___ ____
- Predominantly eliminated in the _____, with minimal ______ excretion
- LOW oral bioavailability
- LARGE fraction of absorbed dose is extracted by the liver
- Distribution is primarily to the LIVER, but also to the SPLEEN, ADRENAL GLANDS and SKELETAL MUSCLE
- Metabolized by CYP 3A4
- Predominantly eliminated in the FECES, with minimal RENAL excretion
Rosuvastatin (Crestor)
- ___ oral bioavailability
- _____ fraction of absorbed dose extracted by the liver
- Distribution is primarily to the _____, but also to _______ ______
- Describe metabolism of Crestor
- Predominantly eliminated in the _____, minimal ______ excretion
- LOW oral bioavailability
- LARGE fraction of absorbed dose extracted by the liver
- Distribution is primarily to the LIVER but also to SKELETAL MUSCLE
- Not extensively metabolized
- Predominantly eliminated in the FECES, minimal RENAL excretion
What is an important consideration when administering Rosuvastatin?
Plasma rosuvastatin concentrations are approximately 2x higher in Asian patients when compared to Caucasian patients - the initial dose in Asian patients should be 5mg (lowest dose we can give)
In general, statins are well tolerated, however there are some adverse effects. What are they?
Myopathy
Rhabdomyolysis
hepatotoxicity
Muscle lysis with severe muscle pain. Diagnosed by measuring blood levels of this enzyme.
Rhabdomyolysis
Creatine kinase - released during muscle injury