Hypertension
Blood pressure is a measure of the force that the blood applies to the walls of the arteries as it flows through them. It’s normal for blood pressure to increase when you exert yourself, or when you feel stressed or anxious. But if your blood pressure is consistently higher than the healthy level when at rest, this is high blood pressure (hypertension).
About high blood pressure:
About three in 10 adults in the UK have high blood pressure. It’s much more common in older people – seven out of 10 people over 70 have high blood pressure.
Symptoms
Most people with high blood pressure don’t have any symptoms. Hypertension is a Silent Killer.
If you have very high blood pressure, or a rapid rise in blood pressure, you may have headaches, problems with your vision, fits or black-outs.
Complications:
If you have high blood pressure, you have an increased risk of major illnesses including:
- cardiovascular disease such as angina (chest pain caused by reduced blood flow), stroke, heart attack, heart failure or atrial fibrillation (irregular heart beat)
- kidney damage
- damaged sight
Causes:
Primary hypertension:
More than nine in 10 people with high blood pressure have what is called primary or essential hypertension. This means that it has no single clear cause.
Although the exact cause of primary hypertension isn’t fully understood, it’s known that some factors to do with your lifestyle can contribute. These include:
- smoking
- obesity
- drinking a lot of alcohol – especially if you binge drink
- lack of exercise
- your diet
If someone else in your family has high blood pressure, you also have a higher risk of developing it.
Secondary hypertension:
Around one in 20 people with high blood pressure have secondary hypertension. This means your condition can be linked to a recognised cause such as:
- kidney disease
- endocrine disease (hormone disorders – a hormone is a regulatory chemical that occurs naturally in your body)
- a narrowing of the aorta (the largest artery leading from the heart) or the arteries leading to the kidneys
Secondary hypertension can also be caused by:
- the contraceptive pill
- steroid medicines
- pregnancy, which can cause pre-eclampsia – this can be serious and harm your baby
Diagnosis:
As you might not have any symptoms, your GP may diagnose high blood pressure when you have your blood pressure taken as part of a medical examination. That’s one good reason to have a regular check-up with your GP, especially if you’re over 50.
Your GP or nurse will measure your blood pressure with a monitor called a sphygmomanometer. A cuff is placed around your upper arm and inflated to a certain level, then deflated slowly.
The result is expressed as two numbers, such as 120/80mmHg.
- The first figure – the systolic blood pressure – is a measure of the pressure when your heart muscle is contracted and pumping blood. This is the maximum pressure in your blood system.
- The second figure – the diastolic blood pressure – is the pressure between heart beats when your heart is resting and filling with blood. This is the minimum pressure in your blood system.
In the UK, hypertension is defined as a consistently increased systolic blood pressure of 140 or over and/or a diastolic blood pressure of 90 or over. If your blood pressure is around this level, your GP will probably want to monitor it regularly.
If you have diabetes, or have had a stroke or TIA (mini stroke) your blood pressure should be lower than this – ideally less than 130/80.
Your GP may ask you to come back for repeat measurements over a number of weeks before suggesting that you have treatment. This is so he or she can check that the high reading is an ongoing problem and not a one-off.
You may also need some tests to see if hypertension is affecting the rest of your body. These may include:
- a urine test – protein in your urine may be the first sign of a kidney problem
- a blood test to check your cholesterol and blood sugar levels, as well as the condition of your kidneys
- an electrocardiogram (ECG) – a test that measures the electrical activity of your heart to see how well it’s working
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Monitoring
24-hour ambulatory monitoring:
You may be given a 24-hour ambulatory monitoring to confirm your diagnosis. This will measure your blood pressure over 24 hours. A monitoring device will be strapped round your waist and attached to a cuff wrapped around your upper arm. The cuff will inflate and deflate automatically throughout the 24 hours and take recordings of your blood pressure.
Blood pressure monitors:
You might consider getting a blood pressure monitor to use yourself at home – discuss this option with your GP.
The British Hypertension Society publishes a list of validated Blood Pressure Monitors.
These have been tested according to the revised BHS protocol (1993) and/or the International Protocol and/or the AAMI Protocol and must achieve a minimum B grade for both systolic and diastolic measurements in order to pass.
When asked for advice I often recommend the A&D UA-767 monitor. This has an A/A validation, is very good value and is readily available online.
“For an adult population, the A&D UA-767 device for the self-measurement of blood pressure satisfies the AAMI criteria, achieved a BHS grade of A/A and can therefore be recommended for monitoring blood pressure in home and clinical conditions by patients with mild-to-moderate arterial hypertension”
Blood Pressure Monitoring 5:227-231
It’s important to take readings on different days – for example you shouldn’t just measure your blood pressure when you feel stressed. Set days in the week to take the measurement so that you can get a consistent reading.
You should continue to have your blood pressure tested regularly by your GP even if you use a blood pressure monitor at home.
Treatment:
You’re likely to need long-term treatment for high blood pressure as it isn’t curable.
You may not need much treatment if you only have slightly raised blood pressure, but regular monitoring is important.
If you have very high blood pressure, you may need to go to hospital for treatment. But it’s much more likely that you will be cared for by your GP and/or a nurse.
Self-help:
Your GP or nurse is likely to discuss lifestyle changes which might help. For example, he or she might advise you to:
- stop smoking
- change your diet to a low-fat, low-salt diet that includes fruit and vegetables
- cut down on alcohol
- cut down on coffee and high-caffeine drinks, such as cola
- take some regular, moderate exercise
- lose any excess weight
It may also help to try to reduce the stress in your life to prevent short-term rises in blood pressure – try relaxation techniques or meditation.
Medicines:
If your blood pressure remains high, your GP may prescribe you one or more of the following antihypertensive medicines.
- ACE inhibitors (eg ramipril) or angiotensin II receptor antagonists (such as candesartan eg Amias) – these relax and widen the walls of your blood vessels.
- Calcium-channel blockers (eg amlodipine) – these help to widen your blood vessels.
- Diuretics (eg bendroflumethiazide) – these increase the amount of water and salt removed from your blood by your kidneys. This lowers the volume of your blood which reduces blood pressure.
- Alpha blockers (eg doxazosin) – these help to widen your blood vessels.
The medicines your GP prescribes will depend on a number of factors, including your age and ethnicity. It may take time to find the best treatment for you; one that balances benefits against any side-effects.
It’s important to be committed to taking your medication every day even if you don’t have any symptoms of high blood pressure.
Resperate:
RESPeRATE is a non-drug method of reducing Blood Pressure. There is some evidence that it is effective. It’s main use would be in patients intolerent of antihypertensive drugs whose blood pressure is not adequately controlled by non-drug methods such as weight reduction, exercise, reduced salt intake and reduced alcohol consumption.
Special considerations
Pregnancy:
If you’re pregnant your blood pressure will be monitored regularly whether you have hypertension or not. It’s possible that you may develop high blood pressure during your pregnancy (pregnancy-induced hypertension) which can lead to serious problems (this is called pre-eclampsia).
If you have high blood pressure and think you may be, or are trying to become, pregnant it’s important that you tell your GP. Certain medicines for treating high blood pressure aren’t suitable for pregnant women.
Ethnic groups:
If you’re of African-Caribbean origin, you’re at a higher risk of hypertension and you should visit your GP for regular monitoring.
You should also be monitored regularly if you’re of South Asian origin because you have a higher risk of developing heart disease and diabetes.