7. Hyperlipidaemia Flashcards
Hyperlipidaemia
High levels of lipids or fat in the blood, i.e lipids or triglycerides
Hyperlipidaemia causes
Hyperlipidaemia can be caused by a fatty diet, kidney, liver disease, hyperthyroidism or drugs such as antipsychotics, corticosteroids, immunosuppressants or anti-retrovirals
Triglycerides/cholesterol targets
Total cholesterol: 5mmol/L or less
Non-HDL cholesterol: 4mmol/L or less
LDL cholesterol “bad cholesterol”: 3mmol/L
Triglycerides: 2.3mmol/L
HDL cholesterol: 1+mmol/L
HDL cholesterol “good cholesterol” lowers the risk of a heart attack or stroke, removes harmful cholesterol
Hyperlipidaemia treatment
For high HDL levels and moderately high triglycerides levels:
Statins
If severe: statins + lipid-lowering drug e.g ezetimibe
-
If triglycerides are still high:
statins + ezetimibe + fenofibrate
For heterozygous familial Hypercholesterolemia:
Ezetimibe
If homozygous: refer to specialist
Lipid-lowering drugs
- Statins
- Ezetimibe (commonly used as statin alternative or adjunct)
- Fibrate (best at lowering triglycerides)
Given under specialist advice:
* Bile acid sequestrant
Statin mechanism of action
Block HMG-CoA reductase involved in cholesterol synthesis. Most effective at lowing LDL cholesterol
Taken for hyperlipidaemia and for the primary/secondary prevention of cardiovascular disease
Stains dose
Short-acting statins taken at night: fluvastatin, simvastatin
Taken at bedtime as cholesterol synthesis is at its highest
Statin intensity
High-intensity statins
defined as statins that reduce LDL by over 40% at a certain dose:
- Atorvastatin 80mg (low dose is 20mg)
- Rosuvastatin: 20mg
- Simvastatin 80mg - risk of myopathy
Statin side effect
Common side effect
- muslce pain - myalgia
Serious side effect
- myopathy, myositis, rhabdomyolysis
patients must report unexplained muscle pain, weakness or tenderness
monitoring creatnine kinase can determine the safe use of statins
-
intersitial lung disease
scar tissue forms on the lungs causing stiffness and makes it difficult to breathe
patients must report cough, difficulty breathing, weight loss -
diabetes mellitus
statins can raise blood glucose and reduce glucose control
Must monitor: hbA1C levels -
hepatotoxicty
As statins work in the liver, they can also cause liver toxicity
if liver-transaminases are more than 3x upper limit STOP
Statins monitoring
- LFT’s
STOP if liver transaminases are more than 3x the upper limit - HbA1C levels
Statins used in caution
Used in caution in:
- Uncontrolled diabetes mellitus
- Hypothyroidism
- Nephrotic syndrome
- Liver disease
uncontrolled diabets mellitus and hypothyroidism as these conditions can raise glucose levels
Managing these conditions first, may resolve the lipid abnormality
Must conduct baseline tests such as HbA1c, TSH
Statins and pregnancy
- Statins are teratogenic
- Women of child-bearing potential must use effective contraception during treatment and 1 month after stopping
- Must be stopped 3 months before attempting to conceive
Statins interactions
-
Statins are metabolised by cytochrome P450 enzymes. Some drugs inhibit this, which increase levels of statin in the blood = myopathy
Macrolides: clarithromycin, erythromycin
CCB’s : verapamil
Patients must temporarily stop the statin if taking any of these antibiotics and then restart once the antibiotic course has been completed
If simvastatin is being taken with diltiazem or verapamil, maximum simvastatin dose should be 20mg
-
Statins interact with fibrates, to increase the risk of Rhabdomyolysis (as fibrates may also cause this aswelll)
Avoid gemfibrozil as risk is too high -
Statins interact with drugs that also cause hepatotoxicity
Flucloxacillin, Tetracycline, Azole antifungals, Carbamazepine, Valproate, Isoniazid, Methotrexate, Sulfasalazine
