Statins are a group of drugs that are prescribed to lower the raised cholesterol levels in the blood.
Besides lowering the bad cholesterol, they reduce the plaques in the arterial walls by breaking them up and improving blood flow through the arteries.
As a result, they significantly reduce the risk of cardiovascular disease. Besides this proven benefit, they also possibly have beneficial effects in the prevention of certain cancers and metabolic syndrome.
New guidelines for statin therapy: Indications
The American College of Cardiology and American Heart Association have identified four categories of people who may have to be put on statins:
- People with very high LDL cholesterol levels of 190 mg/dL (4.9 mmol/L) or higher.
- Those with high LDL cholesterol levels and a history of cardiovascular complications such as a heart attack, stroke, or peripheral vascular disease, or a corrective surgery such as angioplasty or bypass.
- People with raised cholesterol more than 70 to 189 mg/dL and accompanying diabetes.
- People with an LDL above 100 mg/dL and a high 10-year risk of 7.5 percent or more of developing a heart attack. This risk is measured by an online tool developed by the American College of Cardiology and the American Heart Association after you have filled in your present and past medical history details.
How do statins lower cholesterol in the body? Mode of action
Statins are a class of drugs that are used to lower cholesterol. They also act to reduce triglyceride levels.
Statins primarily act by lowering cholesterol production in the liver by inhibiting the action of the enzyme, HMG-CoA reductase which plays a major role in cholesterol synthesis. They are, therefore, also called also HMG-CoA reductase inhibitors
They raise LDL receptor activity and stimulate the liver to remove the LDL and VLDL cholesterol from the blood.
Due to its action on HMG-CoA reductase, statins are usually prescribed to be taken at night because that is when this enzyme is most active in the synthesis of cholesterol in the liver.
Statins are directly associated with reducing the risk of cardiovascular events such as a heart attack and stroke by helping to reduce any cholesterol plaque that has built up in your arterial walls
They are well tolerated – rarely side effects are seen.
Statins are usually recommended once a day. Again, some statins may be recommended twice a day because of the dosage requirement.
- The usual dose ranges from 5 to 40 mg orally once a day in the evening.
- For patients with existing coronary artery disease (CHD) or at high risk for it, the initial dose prescribed is 10 to 20 mg orally once a day in the evening along with “Therapeutic Lifestyle Changes” (TLC).
- For patients at high risk of CHD along with other risk factors such as a current CHD, diabetes, or history of a peripheral vascular disease, stroke, the initial dose prescribed is 40 mg orally once a day in the evening.
- Some statins are more effective than others in reducing elevated cholesterol and triglyceride levels. Crestor (rosuvastatin) 40 mg and Lipitor (atorvastatin) 80 mg at those doses are the most potent in reducing high TG levels.
List of statin examples with generic and brand names
The generic names are followed by the brand names in brackets:
- Atorvastatin (Lipitor)
- Fluvastatin (Lescol)
- Lovastatin (Mevacor)
- Pravastatin (Pravachol)
- Simvastatin (Zocor)
- Rosuvastatin (Crestor)
The different types of statins mentioned above differ in various ways. The most glaring difference is their potency to reduce cholesterol.
Presently, atorvastatin (Lipitor) and rosuvastatin (Crestor) are the most potent, and fluvastatin (Lescol) is the least.
Most people who take statins have minor side effects if any.
Minor side effects can include:
- pins-and-needles sensations
- skin rash
- abdominal bloating
- pain in abdomen
The two most serious side effects are liver failure and skeletal muscle damage. However, these are rare.
Skeletal muscle damage may occur in 1 in 10,000 people who take this drug. This damage is reversible after the person stops taking this drug.
People who are taking simvastatin, atorvastatin, or lovastatin should avoid consuming grapefruit and its juice to avoid the risk of interaction. Grapefruit juice increases the level of simvastatin in your blood and increases the risk of side effects.
How long should you take statins? Can they be stopped?
Once your doctor has put you on statins for your cholesterol problem, consider it as a lifelong commitment. If you stop the drug, your cholesterol levels will rise and put you at risk of cardiovascular events.
However, according to Mayo Clinic, there can be exceptions where the individual has made changes in his diet, lost a good amount of weight, and made substantial changes for the better in his lifestyle.
Secondly, family history of cardiovascular disease should be looked into to evaluate the quantum of risk.
In a case that looks favorable, the dose can be reduced initially, cholesterol levels monitored every six weeks and if the response is encouraging, the drug can be stopped. Following up with your doctor will be the key issue.
In the case of side effects such as liver and muscle damage, if stopping statins is not possible, your doctor will switch you over to other nonstatin cholesterol-lowering drugs.
How often to screen for cholesterol when on statins?
With statins, a reduction in cholesterol levels is seen in about two months’ time, when cholesterol levels should be checked again for comparison with the previous report.
This helps in two ways. It shows the amount of success and also enables your doctor to determine whether any change in dosage is required or not.
Screening should thus be done every six to eight weeks till blood levels normalize. After that, some doctors recommend testing every six months and some advise once a year.
According to the FDA, the benefits of using statins far outweigh the risks of the side effects because the possibility of the risks is small.
In other words, weighing the pros against the cons, the FDA favors going in for the stains rather than against it in spite of the side effects, which are very rare.