Unless you live with kidney disease or someone you’re close to has been affected, then you might not know that much about it and what causes it in the first place.

A number of things can cause kidney disease — a term used by doctors to include any abnormality of the kidneys, even if there is only a bit of damage — such as existing conditions that put a strain on the kidneys like diabetes and high blood pressure. But did you know that high cholesterol can increase your risk of developing kidney disease?

We often associate high cholesterol with cardiovascular diseases, but it can cause problems with your kidneys too.

In this post, we’ll be taking a closer look at the relationship between high cholesterol and kidney disease; read on to have your questions answered.
What is cholesterol and why is it so important?
First of all, what is cholesterol? Despite many people experiencing high cholesterol levels in their lives, there is a lack of knowledge around it.

Cholesterol is a fatty substance (lipid) found in your blood. Your body makes cholesterol (it’s made in the liver) and we also get it from eating meats and other animal products.

Cholesterol plays a vital role in how your body works and we all need cholesterol to keep us ticking over — it’s used to keep your bones, teeth, and muscles healthy, as well as to digest the fats that you eat. It is also integral to the structure of every cell in your body, forming part of the cell membrane.

However, when you have too much cholesterol in your blood, it can cause damaging fatty buildup and blockages in your arteries and blood vessels.

Having high cholesterol can be a result of eating too much fatty food, being overweight, not exercising enough, smoking, and drinking alcohol excessively. It can run in families too.
How does high cholesterol put you at risk of developing kidney disease?
High cholesterol is mostly associated with heart problems: when too much cholesterol builds up in your heart vessels, it can increase your risk of a heart attack (known as coronary heart disease) or stroke.

However, it’s not just the heart that this build-up of fatty deposits affects; it can impact blood supply to other parts of the body, such as your kidneys.

Too much cholesterol can build up in the blood vessels supplying your kidneys. This makes it much harder for the kidneys to work properly.

Compared with other organs and tissues, the kidneys have a particularly rich supply of blood; despite their relatively small size, the kidneys receive around 20% of the heart’s blood output for filtration. This filtration regulates the body’s fluids, filtering waste out and keeping the important stuff.

Kidney function is highly dependent upon sufficient blood pressure, so any interruptions in the blood flow to the kidneys (such as that caused by a build-up of cholesterol) might result in loss of kidney function and tissue damage (i.e. kidney disease).
Cholesterol-lowering drugs may be linked to kidney disease
A secondary reason that high cholesterol puts you at risk of developing kidney disease is that cholesterol-lowering drugs — called statins — have recently been linked to kidney problems.

Statins are a group of medicines that can help lower the level of low-density lipoprotein (LDL) — often referred to as ‘bad cholesterol’ — in the blood, by reducing its production inside the liver.

People who take higher doses of statins (rather than lower doses) to control their cholesterol levels are more likely to develop kidney problems and even be admitted to hospital for acute kidney injury.

This is yet to be proven on a wider scale, but it is still advised that patients speak to their doctors about these risks when these medicines are prescribed. It’s worth noting that the risk is still very rare and that the health benefits of taking statins (such as preventing heart attacks or strokes) still outweigh the increased risk of acute kidney injury for most people.
How do you find out if you have high cholesterol?
Blood cholesterol levels are measured by taking a simple blood test. A small blood sample will be taken by your GP or practice nurse — normally simply by pricking your finger. Alternatively, you may be asked to go for a blood test as your local hospital.

Your blood sample is then checked for the levels of different types of cholesterol (‘good’ HDL, ‘bad’ LDL and triglycerides).

You will then receive your results: too much ‘bad’ cholesterol in your blood is what is known as ‘high cholesterol’. Your GP will be able to take you through what this means moving forward.
How can you manage high cholesterol?
There are many ways that you can manage high cholesterol:

● Eat healthily: include fruit and vegetables, low-fat dairy products, and whole grains in your diet
● Avoid these foods: salt, red and processed meats, saturated fat and cholesterol
● Reduce your alcohol intake
● Stop smoking
● Exercise regularly — 150 minutes is recommended a week
● Use medication for high cholesterol such as statins or aspirin

Speak to your doctor if you’re worried about high cholesterol; particularly if you are a kidney disease patient.

Having high cholesterol can put you at risk of developing kidney disease and having kidney problems, as well as the more obvious associated cardiovascular problems.

If you are worried about high cholesterol or the potential associated risks, it’s a good idea to speak to your GP and arrange a test.

About the author: Scott McDougall (MPharm) is the co-founder and registered manager of The Independent Pharmacy, one of the UK’s leading independent online pharmacies. For more healthcare and treatment advice, visit their website.