Dyslipidemia is an abnormal amount of lipids (e.g. cholesterol and/or fat) in the blood. Usually dyslipidemia is elevation of plasma cholesterol, triglycerides (TGs), or both, or a low high-density lipoprotein level that contributes to the development of atherosclerosis.
(I added this. Please check for accuracy)
What are atheroma and cardiovascular diseases?
Patches of atheroma are like small fatty lumps that develop within the inside lining of blood vessels (arteries). Atheroma is also known as atherosclerosis and hardening of the arteries.
Over months or years, patches of atheroma can become larger and thicker making an artery narrower. This can reduce the blood flow through the artery. Sometimes, a blood clot (thrombosis) forms over a patch of atheroma and completely blocks the blood flow.
What is cholesterol?
Cholesterol is a lipid that is made in the liver from fatty foods that we eat. A certain amount of cholesterol is present in the bloodstream. Some cholesterol is needed to keep the body healthy. Cholesterol is carried in the blood as part of particles called lipoproteins. There are different types of lipoproteins, but the most relevant to cholesterol are:
- Low-density lipoproteins carrying cholesterol – LDL cholesterol. This is often referred to as bad cholesterol, as it is the one mainly involved in forming atheroma. Usually about 70% of cholesterol in the blood is LDL cholesterol, but the percentage can vary from person to person.
- High-density lipoproteins carrying cholesterol – HDL cholesterol. This is often referred to as good cholesterol, as it may actually prevent atheroma formation.
What are triglycerides?
Triglycerides are the main form of fat stored in the body. The fat that is seen on the stomach and hips are made up of triglycerides.
Triglycerides are the end product of digesting and breaking down the fats that are present in food. Any food eaten that isn’t used for energy – carbohydrates, fat, or protein – is also converted into triglycerides. They are bundled into globules and transported through the blood by lipoproteins, like cholesterol. The triglycerides are taken up by fat (adipose) cells, to be used for energy if food isn’t available later.
Causes of hyperlipidaemia?
Hyperlipidaemia is often found when people are overweight or have an unhealthy diet. It can also be the result of drinking too much alcohol.
It can be also be inherited through family genes (known as primary) and approximately 1 person in 500 will have this cause.
It may be also be due to other medical conditions (known as secondary) including
- An underactive thyroid (hypothyroidism).
- Obstructive jaundice.
- Cushing’s syndrome.
- Anorexia nervosa.
- Nephrotic syndrome.
- Chronic kidney disease.
Some prescribed medicines can affect blood cholesterol level, including:
- Thiazide diuretics (used to control blood pressure).
- Glucocorticoids (steroids).
- Cyclosporine (used after organ transplants).
- Antiretroviral therapy (used to treat HIV infection).
- Beta-blockers (used to control heart rate).
- The combined oral contraceptive pill.
- Atypical antipsychotics (used in some mental health problems).
- Retinoic acid derivatives (used in some skin conditions).
How common is hyperlipidaemia?
Hyperlipidaemia is quite common and is known to be a risk factor for cardiovascular disease such as heart attacks and strokes.
Hyperlipidaemia is often found during routine screening. Usually, the diagnosis is made by a simple investigation called the lipid profile done by through a fasting blood test. Fasting means to be without food for at least 12 hours. Drinking water is allowed.
The ranges are as given below:
Desirable Borderline High risk
Cholesterol 200-238 mg/dl 240 mg/dl
Triglycerides 150-199 mg/dl 200-499 mg/dl
HDL Cholesterol 60 mg/dl 35-45 mg/dl
LDL Cholesterol 60-130 mg/dl 130-159 mg/dl 160-189 mg/dl
Cholesterol/HDL ratio 4.0 5.0 6.0
(I think it is important to give these..are these values accurate)
There are also changes that may be visible on the body if one has the inherited form of hyperlipidaemia:
- Premature arcus senilis – this is a white or grey ring that is visible when your doctor looks at the front of your eyes.
- Tendon xanthomata – these are hard nodules that you may find in the tendons of the knuckles and the Achilles (at the back of your ankle).
- Xanthelasmas – fatty deposits in the eyelids.
What can lipid levels be lowered?
Changing from an unhealthy diet to a healthy diet can reduce a cholesterol level. However, dietary changes alone rarely lower a cholesterol level enough to change a person’s risk of cardiovascular disease from a high-risk category to a lower-risk category. However, any extra reduction in cholesterol due to diet will help.
A healthy diet has other benefits too apart from reducing the level of cholesterol.
Briefly, a healthy diet means:
- AT LEAST five portions, or ideally 7-9 portions, of a variety of fruit and vegetables per day.
- A THIRD OF MOST MEALS should be starch-based foods (such as cereals, wholegrain bread, potatoes, rice, pasta), plus fruit and vegetables.
- NOT MUCH fatty food such as fatty meats, cheeses, full-cream milk, fried food, butter, etc. Use low-fat, mono-unsaturated or polyunsaturated spreads.
- INCLUDE 2-3 portions of fish per week.
- LIMIT SALT to no more than 6 g a day (and less for children).
- Red meat, if eaten should be LEAN, or eat poultry such as chicken.
- Food should preferably be fried in a VEGETABLE OIL such as sunflower, rapeseed or olive.
If there is a high risk of developing a cardiovascular disease then medication is usually advised along with advice to tackle any lifestyle issues.
This usually means:
- Medication to lower cholesterol or triglyceride level, usually with a statin medicine. There are several brands of statin medicines. They work by blocking a chemical (enzyme) which is needed to make cholesterol in the liver.
There is no actual target level for people who do not already have cardiovascular disease. However, for those who do have a cardiovascular disease, the aim, if possible, is to reduce TChol to less than 155mg/dL and LDL cholesterol to less than 80 mg/dL. (is the conversion OK)If only triglyceride level is high, omega-3 acid or fibrate tablets are advised instead of a statin.
Advice on lifestyle to reduce your risk of cardiovascular disease:
- Smokers should stop smoking
- A healthy diet should be followed
- Salt intake should be kept to under 6 g a day
- Weight and waist should be kept in check
Regular physical activity should be carried out