Statins and cardiovascular disease: frequently asked questions

Q: I have been told I am at risk of a heart attack or stroke. How can a statin medicine help?

A: Statins lower blood cholesterol levels and reduce the risk of serious cardiovascular events, including heart attack and stroke. In Australia, statin medicines contain one of the following active ingredients: atorvastatin, fluvastatin, pravastatin, rosuvastatin or simvastatin.

If you have had a heart attack or ischaemic stroke, your risk of having another cardiovascular event is high — so a statin is generally recommended to lower that risk.

You can also be at high risk of a cardiovascular event even if you haven’t been diagnosed with cardiovascular disease. This may be because you have a range or combination of factors (such as family history of cardiovascular problems, or conditions such as diabetes or kidney disease) that can cause damage to your blood vessels. In these cases, a statin helps to reduce your chance of experiencing a cardiovascular event in the first place.

Evidence from a large review of clinical trials in people at high risk has shown that statin medicines can substantially lower the chance of having a major cardiovascular event — on average by around 20%.

This means that if you have been told by your doctor you have a 1 in 5 chance of experiencing a cardiovascular event in the next five years, then taking a statin could reduce this to around a 1 in 7 chance.

Back to top


Q: Why can too much cholesterol be harmful?

A: Cholesterol is a type of fat used by our body for important everyday functions, such as making hormones and building and repairing cells. To reach cells throughout the body, cholesterol attaches to a carrier substance called lipoprotein that can travel in the bloodstream. The two most common types of lipoprotein are HDL (high density lipoprotein) or “good” cholesterol, and LDL (low density lipoprotein) or “bad” cholesterol.

High levels of HDL are good for the heart, because this lipoprotein helps cholesterol move from cells, through the blood and into the liver to be processed or excreted from the body. LDL on the other hand carries cholesterol from the blood into cells of the body. This type of lipoprotein can deposit cholesterol in your artery walls, causing a build up of cholesterol (called plaques), which may ultimately cause the arteries to narrow. This is known as atherosclerosis and may result in chest pain (angina), a heart attack or a stroke. So, having high levels of LDL can increase a person’s risk of cardiovascular diseases like heart attack and stroke.

This is why lowering LDL cholesterol levels (and ideally raising HDL cholesterol levels) is an important step for many people to help reduce their cardiovascular risk.

Back to top


Q: How do statins lower cholesterol?

A: While cholesterol can come from animal products in our diet (e.g. meat, eggs, dairy), most of our body’s cholesterol is made in the liver.

Statins work by blocking cholesterol production in the liver. With less cholesterol available, levels in the bloodstream go down.

Other prescription medicines are also available to lower blood cholesterol levels, although statins are the most common treatment.

Back to top


Q: Who should take a statin?

A: In Australia, people are generally prescribed a statin based on their likelihood of having a cardiovascular event, like a heart attack or stroke. The higher your cardiovascular risk, the more likely you will be offered a statin. In some cases this can mean taking a statin even when your cholesterol levels are normal.

Clinical trials, such as the Heart Protection Study (involving over 20,000 people), have shown that statins reduce the chance of cardiovascular events in people at high risk — whether their blood cholesterol level is high or low.

A doctor can estimate how likely it is that you will have a cardiovascular event in the next 5 years (this is known as absolute risk) by calculating a heart and stroke risk score.

To determine risk your doctor will be interested in your blood cholesterol levels in addition to other risk factors including your:

  • age (risk increases as you get older)
  • gender (men tend to have a higher risk)
  • blood pressure (high levels increase risk)
  • lifestyle (e.g. whether you smoke)
  • other medical conditions, such as diabetes.

They will also want to know if there is a history of cardiovascular disease events such as heart attack or stroke in your family.

If you are 45 years or older (or over 35 years for Aboriginal and Torres Strait Islander peoples) speak with your doctor about your heart and stroke risk score. Find out more about absolute cardiovascular risk.

Back to top


Q: Are statins the only way to manage cardiovascular risk?

A: Statins are an important treatment for many people to help them manage their cardiovascular risk.

Dietary and lifestyle changes are also essential to lower your cardiovascular risk. Current guidelines recommend the following:

  • stop smoking
  • eat a healthy diet that includes plenty of fruits, vegetables, wholegrain cereals, lean meat, poultry, fish, eggs, nuts and seeds, legumes and beans, and low-fat dairy products
  • limit saturated and trans fats (also known as hydrogenated or partially hydrogenated fats, and mostly found in processed foods like baked or deep fried goods)
  • limit salt and alcohol
  • be physically active for at least 30 minutes most days
  • maintain a healthy weight.

If you are at high risk of cardiovascular problems, diet and lifestyle alone will not be enough to lower your risk. Your doctor will discuss the need for statins and other medicines (like blood pressuring-lowering medicines) to reduce your cardiovascular risk. This is also the case for some people at moderate risk, who are unable to lower their risk with diet and lifestyle alone.

Find out more about diet and lifestyle.

Back to top


Q: Is it safe to take statins?

A: All medicines (prescription and non-prescription) can have side effects. The chance of developing side effects can vary greatly between people. If a statin has been prescribed or recommended it is important that you discuss possible side effects with your doctor or pharmacist. For most people who are at high risk of heart attack or stroke, the clinical evidence shows that the benefits of lowering cardiovascular risk with a statin medicine outweigh the risk of possible side effects.

Not everyone experiences side effects, even when taking the same medicine at the same dose. All prescription medicines including statins must also show evidence of safety and effectiveness in humans before they can be sold in Australia. The Therapeutic Goods Administration (TGA) is responsible for looking at all the available scientific and clinical information before approving a medicine for use.

Most statin side effects are mild and temporary. A recent review that looked at 135 different studies — including safety data from almost 250,000 people — found that statins were well-tolerated by most people and had few side effects. A slight increase in diabetes (see Do statins cause diabetes?) and abnormal liver enzyme levels was identified.

If you think you are experiencing side effects with your statin or other medicine, speak with your doctor or pharmacist. In some cases your doctor may need to reduce the dose, stop statin treatment or change you to a different statin. Do not stop taking your medicine unless advised to by your doctor.

You can also call NPS Medicines Line on 1300 MEDICINE (1300 633 424) for information about your prescription, over-the-counter and complementary medicines (natural, herbal, vitamins and minerals) — from anywhere in Australia, Monday to Friday, 9am to 5pm AEST (excluding NSW public holidays).

Back to top


Q: Can statins cause muscle damage?

A: Muscle pain or weakness are known side effects of statins. They tend to occur more often in people taking higher doses, but others may also be at greater risk, including older people.

Mild muscle pain (myalgia) is most common and occurs in 5-15% of people taking a statin. More serious muscle-related side effects like muscle inflammation (myositis) and muscle breakdown (rhabdomyolysis ) occur very rarely.

Statins may not be the only reason your muscles feel sore, so discuss any muscle pain or weakness with your doctor so they can investigate the cause.

Find more information about muscle-related side effects in the consumer medicine information (CMI) for your statin.

Back to top


Q: Will I have memory loss if I take a statin?

A: Memory loss has been reported as a possible statin side effect. However, the number of cases is low and for most people the symptoms reversed when the statin was stopped. Recent reviews of available data have looked closely at this possible side effect and conclude that it is rare.

The Therapeutic Goods Administration (TGA) is aware of these reports and is monitoring the situation in Australia. The TGA currently advises people not to stop taking their statin if they experience memory loss, but to talk to their doctor or other health professional.

Back to top


Q: Do statins cause diabetes?

A: A slight increased risk of diabetes has been identified in studies of statins.

In a recent review of trials involving over 91,000 people, there was a higher incidence of type 2 diabetes diagnosed among people taking a statin compared to people who were not taking a statin. The increased risk was very small — one extra case of diabetes for every 255 people treated with a statin over 4 years.

The review also showed that the benefits of taking a statin to lower cardiovascular risk greatly outweighed the possible risk of developing diabetes.

Talk to your doctor if you are taking a statin and are concerned about developing diabetes. Your doctor can discuss the benefits and risks of your medicines with you.

Back to top


Q: What is the "strong evidence" I keep hearing about statins?

A: Evidence for statins has come from many different clinical trials over 30 years. In fact, the complexity of the clinical research is one of the reasons for the current debate about the role of statins.

Trials of statins have been conducted in a wide range of groups, including older and younger people, people at high or low cardiovascular risk, and people with or without diabetes.

These differences can make it harder to interpret the evidence about statins, especially if they find diverse or conflicting results.

In recent years, evidence from statin trials has been carefully analysed by a number of research organisations — including the Cochrane Collaboration, the Cholesterol Treatment Trialists Collaboration and the PROSPERO group. These organisations have conducted large reviews of the evidence for statins by pulling together the results from different trials (a method called ‘meta-analysis’).

Gathering evidence in this way is scientifically valid, and can help to improve our understanding of the impact statins have on cardiovascular risk in many different situations. Overall, these large reviews agree that statins can reduce the chance of heart attack or stroke for people at high risk, regardless of whether they:

  • have had a cardiovascular event before or not
  • have a high or normal blood cholesterol level.

In 2012, the National Vascular Disease Prevention Alliance (NVDPA) released Australian guidelines on managing cardiovascular disease for people at risk. These are based on the latest evidence to enable everyone to receive the best treatment.

Back to top


Q: I’m still not sure if I should take a statin, what should I do?

A: If you are on a statin and have any concerns, do not stop taking your medicine without speaking to your doctor or pharmacist first.

It is important for you and your doctor to discuss your cardiovascular risk and how beneficial a statin may be for you. Taking any medicine has benefits and risks.

Back to top


Find out more

References