Hyperlipidemia Flashcards
Three major lipids in the body?
- Cholesterol
- Triglycerides
- Phospholipids
How does the liver make cholesterol? (Rate-limiting step)
HMG-CoA is converted to mavelonate by HMG-CoA reductase (this enzyme is the target of statins)
What job does a lipoprotein have? Why?
Taxi cab for cholesterol and triglycerides bc they’re insoluble in water
Chylomicrons - characteristics?
First step of packaging digested fats
Transports TG’s, cholesterol, and phospholipids derived from diet from the gut to the liver, adipose tissue, and muscle
What is the most abundant component in chylomicrons?
TG’s (90%)
As chylomicrons make their way to the liver, what component is dropped off at various sites along the way? How?
TG’s; removed by lipoprotein lipase in various cells
VLDL - most abundant component?
TG’s (55%); less than in chylomicrons, a little more cholesterol than in chylomicrons (25%
LDL - most abundant component?
Cholesterol (55%)
HDL - most abundant component?
Proteins (50%)
HDL’s job?
Scoops up cholesterol from peripheral cells and brings it back to the liver
VLDL’s serve as a precursor to what?
LDL’s
Which lipoprotein is known as “bad cholesterol”?
LDL
Which lipoprotein is known as “good cholesterol”?
HDL
Desirable total cholesterol number is below…?
200mg/dL
Desirable LDL number is less than…
100mg/dL
Desirable HDL cholesterol is above…?
60
Desirable TG’s is less than…?
150
Routine initiation of statin therapy in which patient population is not recommended?
- Class II through IV HF
2. Maintenance hemodialysis
What do we use to determine the statin benefit group?
The ASCVD (athersclerotic cardiovascular disease) risk algorithm
What is the first major statin benefit group?
Pt’s with clinical ASCVD (Hx of MI, CVA, unstable angina, etc)
What is the second major statin benefit group?
LDL > 190
What is the third major statin benefit group?
DM (age 40-75) with LDL 70-189mg/dL
What is the fourth major statin benefit group?
- No clinical ASCVD
- No DM
- Age 40-75
- LDL 70-189mg/dL
- 10-yr ASCVD > 7.5%
Name the two high intensity statins:
- Atorvastatin (Lipitor) 40-80mg
2. Rosuvastatin (Crestor) 20-40mg
Which drug class is best for increasing HDL?
Niacin
Which drug class is best for decreasing TG’s?
Fibrates
Which drug class is best for decreasing LDL’s?
Statins
HMG-CoA Reductase Inhibitors - MOA?
Inhibits the first committed enzymatic step of sterol synthesis by BLOCKING HMG-CoA Reductase
Depletes intracellular cholesterol supplies
Causes up-regulation of LDL receptors
Overall decrease in circulating LDL
What time of day are statins taken? Why?
At night, bc your body inherently produces more cholesterol while you sleep (high dose statins can be taken anytime of day)
Most common statin SE’s?
Muscle pain (myalgias) Rhabdomylosis Liver toxicity
What is a routine blood panel (other than lipid) you should obtain prior to and after initiating statin therapy? Why?
LFT - liver issues are common to statins (commonly seen increase in ALT)
Factors that can increase statin-induced myopathy?
- Age >75
- Female
- Liver dysfunction
- Renal insufficiency
- ETOH abuse
- Grapefruit juice (inhibits CYP enzymes)
Absolute CI’s to statins?
- Pregnancy
- Nursing
- Acute liver disease
Statin drug interactions?
- Amio
- Amlodipine
- Dig
- Cardizem
- Coumadin
- Niacin
All statins (except pravastatin) are highly _______ bound.
Protein /// may displace other highly bound drugs (like warfarin)
Which two HGM-CoA Reductase Inhibitors require no dose adjustment in patients with renal insufficiency?
Atorvastatin
Pitavastatin
Which drug class is most beneficial in treating high triglycerides?
Fibrates (Fibric Acid Derivatives)
Fibrates - MOA?
Stimulates lipoprotein lipase activity - hastens the removal of chylomicrons and VLDL’s from plasma, subsequently decreasing TG’s
What is the most effective drug for increasing HDL?
Niacin
What side effect may occur when Gemfibrozil is combined with a statin?
Myopathy and rhabdomyolysis
Gemfibrozil - Pregnancy category?
C
Niacin (aka Nicotinic Acid) - MOA?
Inhibits hepatic synthesis of VLDL by inhibiting lipolysis in adipose tissues, in turn decreasing production of free fatty acids
BLUF: lowers VLDL, raises HDL
Niacin - major clinical benefit?
Reduces major coronary events
Niacin - pregnancy category?
C
How to reduce Niacin flushing?
ASA 30 mins prior to Niacin
Take Niacin with meals
Adverse effects of Niacin - three:
- Liver tox
- Hyperglycemia
- Hyperuricemia
Niacin - CI’s?
- Liver disease
- Severe gout
- Uncontrolled DM
- Active PUD
Monitoring with Niacin?
Check LFT’s at baseline and every 2-3 months
Bile Acid Sequestrants - MOA?
Binds bile acids and salts in the intestine, causing them to be excreted in feces
Decreased levels cause liver to use more existing cholesterol to make bile acids / salts
Overall effect, decreased cholesterol
Bile acid sequestrants best for which type of patient?
Isolated high LDL (because these drugs can increase TG’s)
Bile acid sequestrants can cause impaired absorption of?
Fat-soluble vitamins (A,D,E,K)
Statins
Which bile acid sequestrants are pregnancy category B?
Colistepol
Colesevelam
Which bile acid sequestrant is pregnancy category C?
Cholestyramine
Bile acid sequestrants - adverse effects?
Gi distress, bloating, constipation (many patients are noncompliant with medication due to these effects)
Decreased absorption of:
Warfarin, Thiazides, B-blockers, fat-soluble vitamins (A,D,E,K)
Bile acid sequestrants - CI’s?
Pt’s with high TG’s
Ezetimibe - MOA?
Inhibits intestinal cholesterol absorption
Ezetimibe - clinical use?
Reduce LDL in primary hyperlipidemia
Adjunct to statin therapy (synergistic)
Ezetimibe - pregnancy cat?
C
PCSK9 inhibitor - MOA?
Human monoclonal Ab
Inhibits the PCSK9 enzyme
No PCSK9 —> no degradation of LDLR’s —> increased LDLR’s expressed on hepatocyte surface —> more clearance of LDL’s from circulation —> decreased plasma LDL
What’s so great about PCSK9? What’s so bad?
HIGHLY effective at lowering LDL
CRAZY expensive
Name two PCSK9 Inhibitors:
Alirocumab
Evolocumab
Benefits of Omega-3?
Lowers TG’s, raises HDL
Omega-3 can have an adverse impact on?
Bleeding time (platelets)
Criteria features of high intensity statin primary prevention?
- LDL > 190mg/dL
2. Pt’s w/ LDL 70-190mg/dL AND 10-yr ASCVD > 7.5%
Clinical features of moderate intensity statin primary prevention?
- DM pt’s w/ LDL 70-189mg/dL and 10-yr ASCVD LESS THAN 7.5%
Best drug for lowering TG’s?
Fenofibrate
What is the most common type of lipid abnormality?
Type IIA - familial hypercholesteremia
Type IIA causes increased…?
LDL
Which lipid abnormality is NOT associated with coronary heart disease?
Type I (familial hyperchylomicronemia)