CHOLESTEROL
Cholesterol is a chemical that is made in the liver from fatty
foods that you eat. A certain amount of cholesterol is present in the
bloodstream. You need some cholesterol to keep healthy. However, if
you have a high blood cholesterol level, you have an increased risk
of developing atheroma. A build up of atheroma can cause heart diseases
such as angina and heart attacks, stroke, transient ischaemic attack
(TIA or 'mini-stroke'), and peripheral vascular disease (narrowing
of the arteries to the legs)
What is atheroma?
Patches of atheroma are like small fatty lumps which develop within
the inside lining of arteries (blood vessels). A patch of atheroma
makes an artery narrower, which may reduce the blood flow. Over time,
patches of atheroma can become larger and thicker. The common cause
of angina is due to atheroma which narrows one or more of the arteries
that supply blood to the heart muscle. Sometimes a blood clot (thrombosis)
forms over a patch of atheroma, and completely blocks the blood flow.
Depending on the artery affected, this can cause a heart attack,
a stroke, or other serious problems
Why does atheroma develop?
Everybody has a chance of developing atheroma. However, you are more
likely to develop thick patches of atheroma if you have certain risk
factors which include:
- smoking
- hypertension (high blood pressure)
- high cholesterol level
- diabetes
- obesity
- lack of exercise
- an unhealthy diet
- a strong family history (a father or brother who developed heart
disease or a stroke before they were 55, or in a mother or sister
before they were 65)
- being male
- ethnic group (for example, southern Asians in the UK have an increased
risk)
Some risk factors are more 'risky' than others. For example, smoking causes a greater risk to health than a lack of exercise. Also, risk factors interact. So, if you have two or more risk factors, your health risk is much more increased than if you just have one
Should I have my cholesterol level checked?
In certain situations it is useful to know your cholesterol level to
get a better idea of your health risk, and if necessary, to plan
treatment to reduce your health risk. So, a cholesterol blood test
is commonly advised if:
- you have other significant risk factors, such as diabetes or high
blood pressure. A high blood cholesterol would add to your existing
risk
- you already have angina, had a heart attack, had a stroke or TIA,
have peripheral vascular disease, or have another atheroma related
condition
- a very high cholesterol level runs in the family (familial hypercholesterolaemia)
What is a high cholesterol level?
As a rule, the higher the cholesterol level, the greater the risk to
health. As a guide, a level less than 5 mmol/l is considered 'good',
and is often the target advised to aim for. However, at least half
of adults in the UK have a cholesterol level above 5 mmol/l. An acceptable
cholesterol level depends on whether you have other risk factors.
For example: if you have a raised cholesterol level, and you smoke,
and you have a family history of early heart disease, then you have
quite an increased risk of developing heart disease in the future.
But, the increased health risk is small if you have no other risk
factors apart from a raised cholesterol level
What causes high cholesterol?
In most people, your cholesterol level reflects the amount of fat that
you eat. This is not the full story as different people who eat the
same amount of fat can make different amounts of cholesterol. However,
in general, if you eat less fat your cholesterol level is likely
to go down. In some people a high cholesterol level is due to another
condition. For example, an underactive thyroid gland, obesity, drinking
a lot of alcohol, and some rare kidney and liver disorders can raise
the cholesterol level. In a small number of people a very high level
of cholesterol runs in the family due to an inherited genetic problem.
One example is called familial hypercholesterolaemia
What can I do to lower my cholesterol level?
Lose weight if you are overweight or obese. Even a modest amount of
weight-loss will help. Eating a healthy diet can help to bring your
cholesterol level down. A practice nurse or dietician may advise
you on how to eat healthily. Your doctor or nurse may suggest a 3
month trial of healthy eating (and weight loss where relevant), and
then re-check your cholesterol level. You should aim to reduce any
other 'risk factors' too, for example lack of exercise
Medication to reduce your cholesterol level may be advised if your cholesterol level remains too high after 3 months. A 'statin' medicine is usually used to lower cholesterol. There are several brands of 'statin'. They work by blocking an enzyme (chemical) which is needed to make cholesterol in the liver. If you already have an atheroma related disease (such as angina, etc) a statin medicine is usually advised straight away to reduce the cholesterol level
Further help and information
British Heart Foundation, 14 Fitzhardinge Street, London W1H 6DH, tel
0845 070 8070. Web: www.bhf.org.uk
Source: Adapted with permission from a © document supplied by EMIS and PIP
NHS
Direct 0845 46 47 www.nhsdirect.nhs.uk
