A B C D E F G H I J K L M N O P R S T U V W

HIGH BLOOD PRESSURE - HYPERTENSION

What is High Blood Pressure ?

« Blood pressure » refers to the pressure which exists within the body’s arteries as blood is pumped around the body by the heart. It is expressed as two numbers e.g.120/80. This is because there are two phases in each heart beat – systole, when the blood is pumped out of the heart, and diastole, when blood returns to the heart. The top number is therefore the systolic pressure, and the bottom number the diastolic pressure. The level of blood pressure is mainly controlled by the resistance that blood encounters when it flows through the smaller arteries. It is also influenced by the strength with which the heart beats. Blood pressure tends to rise with age. In younger people, the pressure should probably not be above 120/80 : in older people, say over age 60, 140/80 is probably the upper limit of normal. It is easily measured by your doctor using a cuff wrapped around the arm which is inflated manually. The equipment is called a sphygmomanometer. A raised blood pressure is often first identified when seeing the doctor for some other reason, and when the pressure is routinely measured. This is because most cases of hypertension have no symptoms whatsoever. These only occur when the body has been exposed to high blood pressure for some years. A stroke or heart attack is often the first sign of trouble. Heart failure, with swelling of the ankles (oedema) as well as shortness of breath can occur simply with hypertension. Kidney failure can also develop insidiously from unrecognized (or inadequately treated) hypertension.

How does High Blood Pressure occur ?

In most people with high blood pressure, no cause can be found. This is called essential hypertension. It is commoner in older people and in black people though it can occur at any age and in any race. There are many different causes for the raised blood pressure in the remaining cases. Each of these is quite rare. They usually arise from a number of abnormalities of the kidney or the endocrine (hormone) glands.

Why does High Blood Pressure occur ?

The tendency to high blood pressure often runs in families. There are also many things that can raise the blood pressure in some people. These include too much salt in the diet, a lot of alcohol, stress and the contraceptive pill.

Treatment Involved for High Blood Pressure

A rise in blood pressure is part of the natural ageing process: most people with essential hypertension are in this group. The rarer causes of hypertension are commoner in the younger age group. So it is usual to investigate younger patients in rather more detail. All patients found to have a raised blood pressure have basic blood and urine tests to assess kidney function. If over age 40 and these tests are normal, further tests are not usually done. In younger patients or if there is anything in the basic tests or medical history to arouse suspicion, then more tests are usually performed. These might include a kidney x-ray and further blood and urine tests to look at various hormones and chemicals. If a very high blood pressure is found or hypertension has been present for a long time, then the doctor may suggest an ECG (heart tracing). This helps to check how the heart is coping.

NON-DRUG TREATMENT There are many things which may lower blood pressure without resorting to drugs, especially if only mildly raised. Losing weight is important, and regular exercise may help. The doctor will advise on a healthy target weight. The amount of salt in your diet should be reduced. Salt should not be added to food before tasting it and preferably not during cooking either. Use salt substitutes where possible. Hidden salt, as in bread and convenience snacks, needs to be thought about, too. Alcohol should be cut back to a level which should be discussed with the doctor. If on the oral contraceptive pill, it should be stopped and alternative contraception chosen. Since hypertension raises the risks of heart disease and stroke, it is sensible to reduce other risks, such as smoking and blood cholesterol. No one with hypertension should smoke. Diet needs to be changed so that less fat and more fibre is eaten. Some people with hypertension benefit from relaxation treatment of one form or another. Acupuncture may help.

DRUG TREATMENT The doctor will make the decision as to whether the blood pressure is high enough to need drug treatment. It is important to realize that blood pressure treatment is not designed to make patients feel better. It is used to lessen the chance of having a stroke in the future. The aim of treatment is to lower blood pressure to no higher than 140/80, usually irrespective of age. This has been shown to reduce the risk of stroke, heart attack and probably certain types of dementia. It also reduces the risk of kidney failure. There are now many different types of tablets available, as listed below. In addition, so-called alpha blockers and A2-receptor inhibitors are often used. It is possible to control most people's blood pressure using one or two types of these drugs. Given the wide choice of drugs, there need be no side-effects, and tablets only need to be taken once, or most twice a day. Taking two or more types of drug does not necessarily mean you have serious hypertension: the doctor may do this to reduce your likelihood of having side-effects from any one drug. Having started treatment, tablets usually need to be continued lifelong. Blood pressure will need to be measured at least every 3 months. Some patients are advised to check their own blood pressure. This is a good idea in principle, because some people have a misleadingly high reading, just from the anxiety of visiting their doctor! Unfortunately some of the machines used for home testing are either inaccurate or unreliable. Most patients also benefit from being on a low dose of aspirin to further reduce the risk of stroke. In addition, it is wise to check cholesterol and other fat levels. Lowering these to normal with diet and drugs further reduces the risk of artery damage and its consequences – stroke and heart attack.

During Treatment for High Blood Pressure

If any side-effects (unusual symptoms) occur from the drugs, the doctor must be told. He should be able to find another type of tablet. If blood pressure drops too low, dizziness occurs: again the doctor will lower the dose of tablet or change the type.

If High Blood Pressure is Left Untreated

If hypertension is not detected (or treated), then there is a risk of getting a stroke, heart disease, or kidney failure sometime in the future. The higher the blood pressure, the greater the risk.

Effects on Family of High Blood Pressure

Hypertension is affected by many aspects of everyday life. Food preparation should be discussed with the cooks in the family. A dietitian can often be of help. Reminders to take medicines and have blood pressure checked are also things which family and friends can take on board!