How Can Pharmacogenomics (PGx) Help People With High Cholesterol?

What is High Cholesterol?

Having a “high cholesterol” is when you have too much of the fatty substance called cholesterol circulating in your blood.

As you might be aware, it is mainly caused by eating too much fatty food, not doing enough exercise to burn this off, or being overweight, with smoking and drinking alcohol also contributing. It can also be inherited and run in families, when cholesterol levels can be particularly high (so called “familial hypercholesterolaemia”, of which there are several different types).

You can lower your cholesterol by eating more healthily and getting more exercise. Knowing what foods to avoid or reduce is important and getting the right form of exercise for you is also important as well. Getting professional advice, if you have high cholesterol, could be invaluable to you. For example, knowing the difference between saturated and unsaturated fats in your diet is important so that you make sensible food choices. Apart from these lifestyle behaviours, some people also need to take a medicine to help lower their cholesterol as well.

Why is this important, you might ask? Well, having too much cholesterol can lead to the blocking up of some of your blood vessels (just like pipes furring up in hard water areas). This can then lead to a reduction in the blood flow to important organs such as your heart or brain, and this can result in a higher risk of having a heart attack or a stroke.

Because having a high cholesterol in itself does not cause any symptoms, you will not be aware of it and you can only find out if you have a blood test to check your lipid (fat) levels. This can typically be arranged via your GP. You should ask for a blood test to check your cholesterol level if you are over 40 years old, are overweight, or high cholesterol or heart problems run in your family.

When your cholesterol is measured, it is usually reported as a total cholesterol count, subdivided into LDL-cholesterol (the “bad” cholesterol, that increases your risk of heart problems or having a stroke), HDL- cholesterol (the “good” cholesterol that if high, reduces your risk of these) and Triglycerides (a similar fatty substance to cholesterol).

You should try to eat more of the “healthy” foods, which might include oily fish such as mackerel or salmon, nuts and seeds, fruits and vegetables and brown rice or pasta and brown bread. Use low fat spreads if you can, and avoid butter, lard and ghee. You should also eat less of the “unhealthy” foods such as biscuits, cakes, hard cheeses (like cheddar), cream, sausages, fatty meats and meat pies.

You should aim to exercise more, aiming for at least 2 hours each week, with more being better. Walking, cycling and swimming are good forms to consider, but certainly choose to do something that you enjoy or this won’t last long!

If you need help in cutting down on smoking (none is good here!) or alcohol (some is better than none here, but stick to no more than 14 units each week), the GP is a good place to start, with various types of help available to you.

What medicines are usually taken to lower cholesterol?

The commonest medicines used are statins, which are in tablet form and are taken once each day, usually for life. There are several different ones available in the UK but if these do not work for you or you do not tolerate them, there are other tablets potentially available to take instead, including fibrates, resins etc. There are also some newer injections available. Which medication is right for you is decided with your prescribing doctor, who will monitor your progress in terms of both effectiveness and tolerability of the prescribed medication chosen for you.

How do statins work?

Statins work by reducing the amount of LDL-cholesterol (the bad one!) being produced in the liver, where it is made. It does this by stopping a particular enzyme working called HMG coenzyme A reductase, important in the production pathway of LDL-cholesterol. As a consequence, because your body needs LDL-cholesterol to make bile acids, used by your gut to help digest foods, it draws the LDL-cholesterol out of your blood to be able to do this job. In this way, your blood levels of LDL-cholesterol can be reduced by typically 30 to 50%. It is also good to know that statins can increase your HDL-cholesterol (the good one!) and reduce your Triglycerides as well, which are both good things.

Statins can therefore reduce your risk of getting circulatory diseases including heart disease and peripheral vascular disease (poor circulation), and reduce your risks of having a further heart attack or a stroke, if you have had one of these before. They have been pivotal drugs in the fight to reduce heart attacks and strokes since they became available.

What are the common side effects of statins?

Most people experience no side effects at all when they take their statin. Side effects can occur with all medications, with the most commonly reported side effects from taking a statin being muscle aches and pains.

These muscle aches and pains usually manifest as a generalised muscle discomfort, lasting more than a couple days (similar to those aches you typically get with the “flu”), and which are usually felt all over the body rather than in one area only. It is certainly not a joint pain or a localised cramping of your muscles.

Rarely, muscle pain can progress to other muscle-related problems including myopathy (a muscle disease where the muscle function is affected), myositis (an inflammation of the muscle) or, very rarely, rhabdomyolysis (where muscle cells are actually broken down).

What is Pharmacogenomics (PGx)?

Our DNA affects how our bodies respond to medicine. Not all medications are universally effective: some only work on a minority of individuals, some require adjusted dosages, and others carry the risk of unwanted side effects.

Pharmacogenomic (PGx) testing allows healthcare professionals to write personalised prescriptions and determine optimal dosages based on an individual’s DNA, maximising the likelihood of effectiveness, and minimising the risk of adverse reactions.

How can pharmacogenomics (PGx) help?

Statin associated muscle symptoms (SAMS) can affect about 10% of patients and can lead to patients reducing or discontinuing their medication, which is not ideal. Recent advances in the field of pharmacogenomics (PGx) have shown that there are variations in our genes that can affect how a particular statin might work in us and can help determine our risk of suffering potential side effects, such as SAMS.

Because we are all different genetically, knowing what particular gene variants we have can be very helpful to doctors, as they try to decide which statin to prescribe for us. At the moment, it is a best guess as to which one to start. PGx takes this guessing bit away, helping the doctor by providing them with the necessary information about your genes and then, which statin might be the best one for you to start from the outset.

You can see which statins are included in the Mantara PGx Test here.

BUY YOUR TEST KIT HERE