Dyslipidemia Flashcards
Rate limiting step in cholesterol biosynthesis
HMG-CoA reductase
=critical enzyme in the biosynthesis of cholesterol
Where is the B-48 adoliportoeins formed?
- Intestine
- Found in chylomicrons and their remnants
Where is the B-100 adoliportoeins synthesized? Where is it found?
- Synthesized in liver
- Found in VLDL, LDL, Lp(a) lipoproteins
Risk Factors= “FLASH”
F-Family hx of premature CHD L- Low HDl, <40 mg/dL A- Age: Men>45, Women> 55 S- Smoking: Cigarettes H- HTN; CKD
Risk Equivalents to CHD
- DM
- CAD
- PAD
- AAA
What is the most common cause for low HDL?
Obesity
What enzyme converts VLDL to VLDL remnants via lipolysis?
Lipoprotein lipase
Fibrate MOA
unregulates lipoprotein lipase
Niacin MOA
Decreases both VLDL and LDL levels
Bile acid resins MOA
Bind bile acids–>increasing the excretion of cholesterol in the stool
Statins MOA (2)
- Inhibits HMG-CoA reductase: directly reduces cholesterol production
- LDL receptors unregulated in liver: Lowers LDL
Ezetimibe MOA
Blocks the absorption of cholesterol from the small intestine
Statins primary effect?
Lowers LDL
Statins effect on atherosclerosis?
Prevention of atherosclerosis:
- Stabilizes/regressionof plaques
- Prevents formation of thrombus
- Control inflammatory response
- Improves endothelial function
How much does high-intensity statins decrease LDL?
> or equal to 50%
How much does moderate-intensity statins decrease LDL?
30-50%
How much does low-intensity statins decrease LDL?
<30%
Low intensity statins and dosage
Pravastatin 10-20 mg
Lovastatin 20 mg
Which statin is the most potent?
Pitavastatin
Which drug has the greatest efficacy?
Rosuvastatin 40 mg
What are the benefits of both Atorvastatin and Rosuvastatin?
It doesn’t matter what time of the day you take them
What is Atorvastatin metabolized by?
Cytochrome 3A4= most common enzyme=more drug interactions compared to Rosuvastatin
What is Rosuvastatin metabolized by?
Cytochrome 2C9/2C19
What are the two main differences between Atorvastatin and Rosuvastatin?
- Different metabolism
2. Different distribution
Is Atorvastatin and Rosuvastatin lipophilic?
Atorvastatin
What is Pitavastatin metabolized by?
UGTIA3/UGT 2B7
Severe side effects of Statins
- Rhabdomylosis-Monitor creatine kinase levels
2. Hepatic failure-Monitor LFTs
Contraindications of Statins
- Acute liver dz
2. Pregnancy
What is the risk for developing type 2 DM on statins?
approx. 30%
What lab values do you want monitor with Statins?
- LFT’s @ baseline
- Creatine Kinase levels @ baseline if @ increased risk = renal insufficiency, family hx
3.
What is the anion transporter is there a genetic variation that is associated with severe myopathy and rhabdo induced by statins?
OATP1B1
Atorvastatin drug interaction
3A4 inhibitor and inducer
What is red yeast rice associated with?
Lovastatin
What statin is affected by grapefruit juice? (increased)
Atorvastatin
Rosuvastatin drug interaction
2C9 induces and inhibitor
If someone is on Warfarin, what Statin would you recommend? What would you avoid?
Recommend: Atorvastatin
Avoid: Rosuvastatin= Vitamin K antagonist
What can increase the levels/effects of Rosuvastatin?
Fibric acid derivatives= Gemfibrozil (contraindicated)
Cholesterol absorption inhibitor
Ezetimibe
Ezetimibe MOA
Inhibits cholesterol absorption in the small intestine, both:
- Dietary Cholesterol
- Biliary Cholesterol
What transport protein does Ezetimibe target?
NPC1L1
How much does Ezetimibe reduce LDL by?
18%
What statin would you consider combining Ezetimibe with?
Simvastatin
Ezetimibe contraindications
- Active Hepatic Dz
2. Unexplained persistent elevations in LFTs
Drug interactions
Increased levels with fibrates
Ezetimibe monitoring
LFTs increased: greater combo with statins
Ezetimibe severe side effects
Cholelithiasis: greater in combo with fibrates
How is Ezetimibe excreted?
80% through feces
List PCSK9 inhibitors
- Alirocumab
2. Evolucmab
PCSK9 inhibitors MOA
Monoclonal antibodies inhibit PCSK9= Reduce LDL up to 70%
Where is PCSK9 found? It’s function?
- Protease in Liver
- Degradation of hepatocyte LDL=increases LDL levels
Who should we consider PCSK9 inhibitors for?
- Adults w/ heterozygous familial hypercholesterolemia
- Primary hyperlipidemia- (Homozygous familial hypercholesterolemia)
- ADD onto maximal tolerated statin dose and/or exetimibe
- Intolerance of statins
PCSK9 inhibitors adverse reactions
- URI and flu-like sx’s
- Local runs @ injection site(frequently)
- Hypersensitivity (rare)
How are PCSK9 inhibitors given?
SQ every 2 weeks
Why do we want to monitor lipid panels every 4-8 weeks in PCSK9 inhibitors?
Patient adherence
Define and list MTP inhibitor
MTP: Microsomal Triglyceride Transfer Protein inhibitor
= Lomitapide
MTP inhibitor MOA
- Binds directly to and inhibits MTP
- Prevents assembly of apo-B containing lipoproteins
- Reduced production of chylomicrons and VLDL
- Reduced plasma LDL
MTP inhibitor indication
Homozygous familial hypercholesterolemia
Sever side effects
HEPATOTOXICITIY=BLACK BOX WARNING
What program are MTP inhibitors through?
JUXTAPID REMS PROGRAM
Other MTP inhibitor major side effect
GI upset: Diarrhea=79%
PK of MTP inhibitor
- 99.8% protein bound
- Hepatic metabolism of CYP3A4-inducer and inhibitors are going to effect level of this drug
- Renal elimination
What drug levels with MTP inhibitor increase?
Lovastatin
MTP inhibitor contraindications
- Pregnancy
2. Active hepatic dz/impariement
What is recommended with MTP inhibitor to avoid GI effects?
Low fat diet, <20%
Mipomersen sodium (Kyanamro) MOA
Inhibitor of apoldprotein B-100 synthesis
Mipomersen sodium (Kyanamro) major side effect
BLACK BOX WARNING=HEPATOTOXICITY
KYANMOS REMS
Fibrates MOA
Upregulates lipoprotein lipase:
- Increase catabolism of VLDL
- Elimination of TG-rich particles
What is the primary effect of Fibrates?
TG lowering=35-50%
What may fibrates potentially increase?
LDLs in pt’s with elevated TGs
Severe side effects of fibrates?
- Acute renal failure!!!
2. Cholelithiasis
Fibrate contraindications
- Severe renal impairment CrCl <30
- Hepatic dysfunction
- Breastfeeding
Fibrate drug interactions
- Statins!!!! Increases risk of myopathies–> rhabdo
- Warfarin
- Sulfonyluereas- may enhance hypoglycemic effects
Nicotnic Acid MOA
Inhibits synthesis and secretion of VLDL–>and therefor LDL
Niacin indication
- High LDL and low HDL
2. Isolated triglyceridemia
Why has Niacin fallen out of favor?
Has not shown to decrease morbidity and mortality
What is unique to Nicotinic Acid dosing?
Titration
3 main side effects of Nicotinic Acid
- Flushing
- Hyperglycemia
- Hyperuricemia=Increaed risk for gout
Nicotinic Acid drug interactions
- Anticoagulants- May increase bleeding time
2. Statins-Increase risk of myopathies
Caution Nicotinic Acid use with?
- Diabetics
2. Renal impairment
Bile Acid Sequestrants MOA
- Cholesterol is a precursor to bile acids
- Bind with bile acids in intestines–>eliminated via feces
- Increased bile acid secretion increased cholesterol catabolism to form more bile acids
BASs therapeutic effects
Decrease LDL 15-30%
Minimal effect on HDL and TG
Severe side effects of BASs
Bleeding with chronic use
=affects Vitamin K absorption
BASs drug interactions
All bind with other medications, absorbant!!!
Omega-3 Acid Ethyl Esters (O3FAs)
Lovaza
O3FAs drug interactions
Inhibit platelet aggregation and cause bleeding