Cholesterol is a lipid (fat chemical) that is made in the liver from fatty foods that we eat. A certain amount of cholesterol is present in the bloodstream. You need some cholesterol to keep 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 mainly involved in forming a cholesterol rich fatty deposit in blood vessel wall
High density lipoproteins carrying cholesterol – (HDL cholesterol); this is often referred to as ‘good cholesterol’ as it may actually prevent fat deposition in blood vessels
Why is high cholesterol bad?
High cholesterol in blood can get deposited in blood vessel walls that supply blood to the major organs such as heart or brain resulting in poor blood circulation to these organs. At a site where cholesterol is deposited in a blood vessel, a blood clot can form which can give rise to a heart attack or a stroke. Such disease are known to be a main cause of hospital deaths in Sri Lanka.
Who should have blood cholesterol tested?
It is advisable for all persons aged 40 years or more, those of any age with a strong family history of early heart disease or stroke, and persons of any age with a family history of a hereditary lipid (cholesterol) disorder to have blood cholesterol tested. If you are found to have a high risk of developing heart disease or stroke, you will usually be advised to take drugs to lower your cholesterol and other lipids.
What factors affect the blood level of cholesterol?
In most people, cholesterol level reflects the amount of fat that you eat. However, different people who eat the same amount of fat can have different amounts of cholesterol. In general, if you eat less fat, your cholesterol level is likely to go down. In some, a high cholesterol level may be due to predisposing conditions. For example those having an underactive thyroid gland, persons who are obese or drink too much alcohol as well as those with rare kidney and liver disorders are likely to have raised blood cholesterol levels. In some, a very high level of cholesterol runs in the family due to an inherited genetic problem. One such problem is called Familial hypercholesterolaemia.
Do all people with a high cholesterol level need treatment?
Treatment is needed only for people at a high risk of developing a cardiovascular disease. They include:
- People at higher risk of cardiovascular disease due to presence of multiple risk factors or familial hypercholesterolaemia
- Patients with existing cardiovascular disease such as those who had a heart attack or gets angina
- Those with kidney disorders
Can diet lower cholesterol level?
Changing from an unhealthy diet to a healthy diet can reduce cholesterol level. However, dietary changes alone rarely lower the cholesterol level adequately to alter the risk of cardiovascular disease from a high risk to a lower risk category.
What drugs are given to reduce cholesterol and how should they be taken?
A group of drugs called statins usually lowers blood cholesterol level. Drugs of this group include, atorvastatin, simvastatin, rosuvastatin available in several brand names. They work by blocking an enzyme (chemical) which is needed to make cholesterol in the liver. These drugs are taken once a day, ideally in the evening at about 5-6 pm. But, if you forget to take the drug at that time, take it later on at night.
Statins are usually well tolerated. Doctors will usually check your liver function after you started these drugs, as some patients can develop abnormalities of liver function. They can also cause muscle pain and if you experience any muscle or body pains, you must inform your doctor. Once treatment is started, your lipid profile will be repeated in about 2 months to check whether cholesterol level has reduced satisfactorily. If not, the dose may be increased. Rarely, additional drugs may be needed to reduce cholesterol if the level is very high. Once you achieve good control, doing regular cholesterol testing is not necessary.
Apart from drugs to reduce cholesterol, do I need any other treatment?
If you are at high risk of developing a cardiovascular disease, then following treatment may be given along with advice to tackle any lifestyle issues.
– Anti hypertensives are recommended if your blood pressure is raised
– A daily low dose of aspirin may be given depending on your age and other factors. Aspirin helps to prevent blood clots formingon patches of cholesterol deposits inside blood vessels
– Where relevant, the following will also help:
- stopping smoking,
- eating a healthy diet with higher fruit, vegetable, fish intake and reducing fatty food and salt intake
- keeping your weight and waist to ideal levels
- taking regular physical activity such as walking
- reducing intake of alcohol if you have been drinking too much alcohol
Professor Priyadarshani Galappatthy
MBBS, MD, Dip Med Tox(Cardiff), FRCP (Lond), FCCP
Consultant Physician and Professor in Pharmacology
Faculty of Medicine
University of Colombo