Understanding statins and dementia

Statins are a type of medication prescribed to reduce cholesterol and prevent heart disease and related complications, such as heart attacks and strokes.

While some people are concerned that statins could cause dementia, research shows that for people with high cholesterol or heart disease, taking a prescribed statin may prevent damage to the brain and blood vessels and reduce the risk of dementia.

Our dementia specialist Admiral Nurses explain what statins are, what they are used for and how they might help to reduce the risk of dementia.

What is cholesterol?

Cholesterol is a fatty substance that is made by the body and is also in some of the foods we eat. We all need cholesterol to keep our cells healthy, but too much of the wrong type can cause health problems.

There are two types of cholesterol:

• low-density lipoprotein (LDL) or non-high-density lipoprotein (non-HDL): this is often known as ‘bad cholesterol’ as it leads to a build-up of fat in the arteries, which can be dangerous
• high-density lipoprotein (HDL): this is often known as ‘good’ cholesterol as it removes ‘bad’ cholesterol from the body

On this page, when we use the term ‘high cholesterol’, we are referring to ‘bad’ LDL cholesterol.

What are statins?

Statins are a group of medications used to help lower cholesterol levels. They come as tablets to be taken once a day.

How do statins affect the body and brain?

High levels of cholesterol can cause fat to build up in the arteries. This narrows the arteries, which can interrupt the blood supply to the body and brain and lead to health problems like heart disease and strokes. These fatty deposits can also break off and cause clots in the blood vessels. This can happen anywhere in the body, including the brain.

Statins work by blocking a specific enzyme which the liver uses to produce cholesterol, reducing the levels in the body. They can’t remove any existing fatty build-up in the arteries, but they can stop it getting worse.

Why are statins prescribed?

Statins are prescribed to reduce cholesterol levels and help to prevent further damage to the arteries.

What conditions are statins prescribed for?

Statins may be prescribed for people who have high cholesterol or cardiovascular disease (CVD). They may also be prescribed for people who are at risk of developing CVD within the next 10 years. This risk is based on the person’s personal and family history.

CVD includes:

• coronary heart disease: a restriction in blood supply to the heart
• angina: chest pain caused by reduced blood flow to the heart
• heart attacks: when the supply of blood to the heart is suddenly blocked
• stroke: this happens when the supply of blood to the brain becomes blocked
• transient ischaemic episodes (TIAs): ‘mini strokes’

Cholesterol and dementia

Research has shown that people who have high cholesterol between the ages of 40 and 60 are at an increased risk of developing dementia.

High cholesterol can lead to a build-up of proteins in the brain which form ‘plaques’ and ‘tangles’ that are linked to Alzheimer’s disease.

The blockages in arteries caused by high cholesterol levels can also lead to conditions like high blood pressure and stroke, which can increase the risk of vascular dementia.

Do statins increase the risk of developing dementia?

People sometimes worry that taking statins could increase the risk of developing dementia. This could be because a small number of people develop some memory loss and confusion when they start taking statins, which they may attribute to dementia.

However, these symptoms are side effects of the medication and are reversed if the person stops taking statins, unlike the symptoms of dementia, which cannot be reversed and always get worse over time.

Evidence of statins lowering dementia risk

Studies have shown that people who are taking appropriately prescribed statins are around 20% less likely to develop all forms of dementia than those who aren’t taking statins.

However, taking statins where there is no reason to do so has no benefit on memory or thinking skills.

Statins and Alzheimer’s disease risk

Studies have shown statins reduce the risk of Alzheimer’s disease by around 30% in people with high cholesterol, CVD or a high risk of CVD, compared to those who aren’t taking statins.

Statins and vascular dementia risk

People who are taking appropriately prescribed statins are around 7% less likely to develop vascular dementia.

Ongoing research

Research into the impact of statins on dementia is ongoing. There is evidence that if someone is taking statins for high cholesterol, taking them as prescribed on a long-term basis could help. However, taking statins is not thought to reduce the risk of dementia in people who have healthy cholesterol levels.

More research is needed into how statins could affect the chances of developing dementia.

Questions to ask your healthcare provider before starting statins

There are a range of questions you can ask before starting to take statins, including:

• What are the potential side effects?
• What should I do if I experience side effects?
• Could these interact with any existing medications I am taking?
• What other changes should I make while taking them?
• Are there any alternatives to taking statins?
• Lifestyle changes like eating a healthy diet, getting regular exercise, stopping smoking and keeping alcohol consumption within recommended limits can also reduce cholesterol levels

How we can support you

To speak to a dementia specialist Admiral Nurse about statins or any other aspect of dementia, please call our free Dementia Helpline on 0800 888 6678 (Monday-Friday 9am-9pm, Saturday and Sunday 9am-5pm, every day except 25th December) or email helpline@dementiauk.org. Alternatively, you can pre-book a phone or video call with an Admiral Nurse.