Statins are medications that help decrease the blood cholesterol level. This review will discuss the mechanism of action of statins, what conditions they treat, nursing implications, side effects, and patient education.
Don’t forget to take the statins NCLEX questions quiz after reviewing this material.
Lecture on Statins
Statins Pharmacology Review for Nursing
What are they? Statins are cholesterol lowering medications that help lower the bad cholesterol in the body ( ex: LDL…low-density lipoprotein) and this helps treat various conditions.
Statins are easy to identify because their generic name ends with statin:
- Simvastatin
- Lovastatin
- Pravastatin etc.
How do statins lower cholesterol levels in the blood? Statins inhibit an enzyme called HMG-CoA reductase ….so they’re known as HMG-CoA reductase inhibitors (hydroxymethylglutaryl–coenzyme A reductase).
HMG-CoA reductase is an enzyme that is a major player with cholesterol synthesis in the liver. This enzyme causes HMG-CoA to convert into mevalonic acid which activates the mevalonate pathway. The end result of this pathway is cholesterol synthesis.
If a patient is taking a statin: HMG-CoA reductase is inhibited and HMG-CoA can NOT convert into mevalonic acid and the activation of the mevalonate pathway can NOT happen. The end result is that cholesterol synthesis can NOT happen and this will decrease cholesterol levels.
Because the synthesis of cholesterol in the liver is hindered it causes the liver to remove the bad cholesterol (LDL) from the blood by increasing LDL receptors and this also helps drop the LDL levels in the blood. Plus, HDL levels will increase and help remove more LDL from the body and this is even more helpful in lowering cholesterol levels.
Why does cholesterol need to be lowered in the blood? Not all cholesterol is bad and needs to be lowered in the blood….
- LDL (low-density lipoprotein): it’s considered the “bad cholesterol” and this number should be low. Generally, the LDL should be < 100 mg/dL.
- LDL is a fatty substance that sticks to vessels walls (causing fatty plaques) and leads to a condition called atherosclerosis. Unfortunately, over time these fatty plaques can grow/rupture and decrease blood flow in the vessel. This can lead to a stroke or heart attack. Statins can help decrease LDL levels.
- HDL (high-density lipoprotein): it’s considered the “good cholesterol” and this number should be HIGH. Generally, the HDL should be >60 mg/dL.
- This substance actually helps remove LDL from the blood so it doesn’t have the chance to stick to vessel walls. Statins can slightly help increase HDL levels.
Statins are Used to Treat what Conditions?
- Treat high cholesterol levels
- Preventive treatment for patients at risk for coronary artery disease due to atherosclerosis (ex: heart attack or stroke)
- Help stabilize fatty plaques in patients with CAD due to atherosclerosis (which can reduce the chances of them rupturing )
Nurse’s Role with Statins
To help us remember notable side effects and the nurse’s role, remember the mnemonic “statin”.
Sore muscles?
- This is a side effect of statins for some patients. It may be reported as muscle weakness as well. Why does this occur? They think it may be because statins decrease the amount of coenzyme q10, which creates muscle cell energy.
- If muscle issues occur, the doctor may check the patient for an elevated creatine kinase.
- Creatine kinase is a protein found in skeletal muscle (also in the heart and brain). If it’s found in the blood in high amounts (>10 x the upper limit of normal) it shows there is skeletal muscle damage. If this occurs the statin is stopped because this can progress to…
- Statin-induced rhabdomyolysis: this occurs when muscle tissue breaks down which causes myoglobin to leak into the blood and eventually this substance goes to the kidneys and this causes renal failure.
- Risk of this condition increases when statins are used with other drugs such as the Fibrates (fibric acid derivatives)
- ex: Fenofibrate , Gemfibrozil
- Risk of this condition increases when statins are used with other drugs such as the Fibrates (fibric acid derivatives)
- Statin-induced rhabdomyolysis: this occurs when muscle tissue breaks down which causes myoglobin to leak into the blood and eventually this substance goes to the kidneys and this causes renal failure.
Toxicity increased with grapefruit or grapefruit juice consumption….increases statin toxicity
ALT/AST monitored regularly….these are liver enzymes…risk of liver failure
Therapeutic effects: lowering cholesterol levels….decrease LDL, increase HDL
Increase blood glucose in patients at risk for type 2 diabetes
Not a cure…diet and exercise very important
- Advise patient these medications don’t cure high cholesterol levels, and they should maintain a healthy diet with exercise.
References:
Controlling Cholesterol with Statins. (2017). Retrieved 28 September 2020, from https://www.fda.gov/consumers/consumer-updates/controlling-cholesterol-statins
Million Hearts® The Scoop on Statins. (2020). Retrieved 21 September 2020, from https://millionhearts.hhs.gov/learn-prevent/scoop-on-statins.html