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Blood pressure (high)

 

High blood pressure rarely has obvious symptoms.

Around 30-40% of people in Ireland have high blood pressure but many don't know it. If left untreated, high blood pressure increases your risk of a heart attack, stroke vascular disease and kidney failure.

The only way of knowing there is a problem is to have your blood pressure measured.

All adults should have their blood pressure checked at least every five years. If you haven't had yours measured, or you don't know what your blood pressure reading is, ask your GP to check it for you.

What is high blood pressure?

Blood pressure measures how strongly blood presses against the walls of your arteries (large blood vessels) as it is pumped around your body by your heart. If this pressure is too high it puts a strain on your arteries and your heart, which makes it more likely that you will suffer a heart attack, a stroke or kidney disease.

Blood pressure is measured in millimetres of mercury (which is written as mmHg) and it is recorded as two figures:

  1. systolic pressure: the pressure of the blood when your heart beats to pump blood out
  2. diastolic pressure: the pressure of the blood when your heart rests in between beats

For example, if your GP says your blood pressure is '140 over 90', or 140/90mmHg, it means you have a systolic pressure of 140mmHg and a diastolic pressure of 90mmHg.

You are said to have high blood pressure (medically known as hypertension) if readings on separate occasions consistently show your blood pressure to be 140/90mmHg or higher.

A blood pressure reading below 130/80mmHg is considered to be normal.

Who is most at risk?

Your chances of having high blood pressure increase as you get older. There is often no clear cause of high blood pressure but you are at increased risk if you:

  • are overweight
  • have a relative with high blood pressure
  • are of African or Caribbean descent
  • eat a lot of salt
  • don't eat many fruit and vegetables
  • don't take enough exercise
  • drink a lot of alcohol

If you fall into any of the groups listed above, you should consider making changes to your lifestyle to lower your risk of high blood pressure. You should also consider having your blood pressure checked more often, ideally once a year especially if you are over 60 years of age.

Prevention and treatment

You can take effective steps to prevent high blood pressure by:

  • losing weight if you need to
  • exercising regularly
  • eating a healthy diet
  • cutting back if you drink a lot of alcohol
  • stopping smoking
  • cutting down on salt and caffeine

Find out more about how to prevent high blood pressure.

If your blood pressure is found to be high, it will need to be closely monitored until it is brought under control. Your doctor will usually suggest changes to your lifestyle but will also usually have to prescribe medication to achieve this. Find out more about how blood pressure is treated.



High blood pressure usually has no obvious symptoms and many people have it without knowing.

Untreated high blood pressure can lead to serious diseases, including stroke and heart disease. The only way to know if you have high blood pressure (medically known as hypertension) is to have your blood pressure measured. All adults should get their blood pressure checked at least once every five years.

In some rare cases, where a person has very high blood pressure, they can experience symptoms including:

  • a persistent headache
  • blurred or double vision
  • shortness of breath

Visit your GP as soon as possible if you have any of these symptoms.

Find out more about who is at risk of high blood pressure.  

Pregnancy

If you are pregnant, you should have your blood pressure checked on a regular basis, even if it is not high.

Watching your blood pressure while you are pregnant reduces your risk of developing pregnancy-induced hypertension.

This can lead to a serious condition called pre-eclampsia where there is a problem with the placenta (the organ that links the baby’s blood supply to the mother’s).

In over 90% of cases, the cause of high blood pressure (hypertension) is unknown but several factors can increase your risk of developing the condition.

Where there is no specific cause, high blood pressure is referred to by doctors as primary high blood pressure (or essential high blood pressure).

Factors that can raise your risk of developing primary high blood pressure inlcude:

  • age: the risk of developing high blood pressure increases as you get older
  • a family history of high blood pressure  (the condition seems to run in families)
  • being of African or Caribbean origin
  • a high-fat diet
  • a high amount of salt in your food
  • a lack of exercise
  • being overweight
  • smoking
  • drinking large amounts of alcohol
  • stress

Known causes

About 1 in 10 cases of high blood pressure are the result of an underlying condition or cause. These cases are referred to as secondary high blood pressure.  

Common causes of secondary high blood pressure include:

Find out about how to get your blood pressure tested.

Glossary

Adrenaline
Adrenaline is a hormone produced at times of stress that affects heart rate, blood circulation and other functions of the body.
Genetic
Genetic is a term that refers to genes- the characteristics inherited from a family member
Heart attacks
A heart attack happens when there is a blockage in one of the arteries in the heart.
Kidney
Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.
Origin
The origin is the place where something begins.

The only way to know if you have high blood pressure (hypertension) is to have your blood pressure checked.

This can be done by your GP or another healthcare professional, or you can check it yourself with a home testing kit.

Healthy adults aged over 40 should have their blood pressure checked at least once every five years and yearly over the age of 60 years.

If you are at an increased risk of high blood pressure, you should have your blood pressure checked more often, ideally once a year.

Getting checked by your GP

Blood pressure checks are usually available on request at most GP surgeries and health clinics.

Blood pressure is often measured using a sphygmomanometer, a device which consists of a stethoscope, arm cuff, dial, pump and valve.

The cuff is placed around your arm and pumped up to restrict the blood flow. The pressure is then slowly released as your pulse is checked using the stethoscope.

Hearing how your pulse beats after the cuff is released allows a measurement to be taken on the mercury scale, giving an accurate reading of your blood pressure.

Many GP surgeries now use digital sphygmomanometers, which measure your pulse using electrical sensors.

Before having your blood pressure taken, you should rest for at least five minutes and empty your bladder.

To get an accurate blood pressure reading, you should be sitting down and not talking when the reading is taken.

Blood pressure readings

Having one raised blood pressure reading does not necessarily mean you have high blood pressure. Blood pressure can fluctuate throughout the day. Feeling anxious or stressed when you visit your GP can raise your blood pressure.

Therefore, your GP will need to take several readings over a period of time, usually every month, to see if your blood pressure level is consistently high.

You may also have blood and urine tests to check for conditions that are known to cause an increase in blood pressure, such as kidney disease.

You may be given a blood pressure kit to take home so you can monitor your blood pressure level throughout the day.

Increasingly doctors use 24 hour blood pressure monitors that automatically check your blood pressure every 30 minutes to 1 hour. These devices are thought to be more accurate that Sphygmomanometers and can provide additional useful data to your doctor about blood pressure while you sleep and how your blood pressure varies throughout the day.

Home testing kits

Portable testing kits that measure your blood pressure at home or on the move can be a useful way of getting a more accurate reading.

This is because some people become anxious in medical clinics, which can cause the blood pressure to rise, a condition called white coat hypertension.

Home or portable blood pressure monitoring kits may show that your blood pressure is in fact normal when you are relaxed.

You can buy a variety of testing kits so you can monitor your blood pressure at home or while you're out and about.

It is important to buy a blood pressure monitor that is reliable and gives accurate readings and to take advice from an expert on how to use it.

Understanding your reading

Blood pressure measures how strongly blood presses against the walls of your arteries (large blood vessels) as it is pumped around your body by your heart.

It is measured in millimetres of mercury (which is written as mmHg) and it is recorded as two figures:

  • systolic pressure: the pressure of the blood when your heart pushes blood out
  • diastolic pressure: the pressure of the blood when your heart rests in between beats

For example, if your GP says your blood pressure is '140 over 90', or 140/90mmHg, it means you have a systolic pressure of 140mmHg and a diastolic pressure of 90mmHg.

Ideally, your blood pressure reading should be below 120/80mmHg. However, anything under 130/80mmHg is generally considered normal.

You are said to have high blood pressure if readings on separate occasions consistently show your blood pressure to be 140/90mmHg or higher.

If you have kidney disease, diabetes or a condition that affects your heart and circulation, your target blood pressure should be below 130/80mmHg.

Find out how to treat high blood pressure.

Your blood pressure reading

Ideally, your blood pressure reading should be below 120/80mmHg.

However, anything under 140/90mmHg is generally considered normal.

Useful Links

You can take effective steps to lower your blood pressure with changes to your lifestyle and by taking medication.

Your choice of treatment will depend on your blood pressure level and your risk of developing a cardiovascular disease, such as a heart attack or stroke.

  • If your blood pressure is slightly above 130/80mmHg but your risk of cardiovascular disease is low, you should be able to lower your blood pressure by making some changes to your lifestyle.
  • If your blood pressure is moderately high (140/90mmHg or above) and you're at risk of cardiovascular disease in the next 10 years, treatment will involve medication and lifestyle adjustments.
  • If your blood pressure is very high (180/110mmHg or above) you will need treatment soon, possibly with further tests, depending on your health.

Lifestyle changes

Below are some changes to your lifestyle to reduce high blood pressure. Some of these will lower your blood pressure in a matter of weeks, others may take longer.

  • Cut your salt intake to less than 6g (0.2oz) a day.
  • Eat a healthy, low-fat, balanced diet, including plenty of fresh fruit and vegetables.
  • Be active: being physically active is one of the most important things you can do to prevent or control high blood pressure
  • Cut down on alcohol.
  • Stop smoking. Smoking greatly increases your chances of getting heart and lung diseases.
  • Maintain a healthy weight.
  • Drink less coffee, tea or other caffeine-rich drinks such as cola. Drinking more than four cups of coffee a day may increase your blood pressure.
  • Relaxation therapies, such as yoga, meditation and stress management. These treatments are not normally provided by the HSE.

The more healthier habits you adopt the greater effect is likely to be on lowering your blood pressure.

In fact, some people find that, by sticking to a healthy lifestyle, they do not need to take any medicines at all. Find out more about preventing high blood pressure.

Medication

There is a wide range of blood pressure lowering medicines to choose from. You may need to take more than one type of medication because a combination of drugs is sometimes needed to successfully treat high blood pressure.

In some cases, you may need to take blood pressure-lowering medication for the rest of your life. However, if your blood pressure levels stay under control for several years, you might be able to stop your treatment.

Most medications used to treat high blood pressure can produce side effects but the large choice of blood pressure medicines means that these can often be resolved by changing treatments.

Let your GP know if you have any of the following common side effects while taking medication for high blood pressure:

  • feeling drowsy
  • a dry cough
  • dizziness, faintness or light-headedness
  • a skin rash
  • muscle cramps
  • ankle swelling
  • erectile impotence

Below are the most widely used medications for treating high blood pressure. Different high blood pressure treatments work better for different ethnic groups. Your GP will consider your ethnic background when making a treatment plan.

ACE inhibitors

Angiotensin-converting enzyme (ACE) inhibitors reduce blood pressure by relaxing your blood vessels. The most common side effect is a persistent dry cough. If side effects become particularly troublesome, a medication that works in a similar way to ACE inhibitors, known as an angiotensin-2 receptor antagonist, may be recommended.

ACE inhibitors can cause unpredictable effects if taken with other medications, including some over-the-counter ones. Check with your GP or pharmacist before taking anything in combination with this medication.

Calcium channel blockers

Calcium channel blockers keep calcium from entering the muscle cells of the heart and blood vessels. This widens your arteries (large blood vessels) and reduces your blood pressure.

Drinking grapefruit juice while taking some types of calcium blockers can increase your risk of side effects. You can discuss the possible risks with your GP or pharmacist.

Diuretics

Sometimes known as water pills, diuretics work by flushing excess water and salt from the body through urine.

Beta-blockers

Beta-blockers work by making your heart beat more slowly and with less force, thereby reducing blood pressure.

Beta-blockers used to be a popular treatment for high blood pressure but now they only tend to be used only rarely. This is because beta-blockers are considered to be less effective than the other medications used to treat high blood pressure.

Beta-blockers can also interact with other medications, causing possible side effects. Check with your GP or pharmacist before taking other medications in combination with beta-blockers.

Don't suddenly stop taking beta-blockers without first consulting your GP. Stopping suddenly will lead to serious side effects, such as a rise in blood pressure or an angina attack.

Alpha-blockers

Alpha-blockers are not usually recommended as a first choice for lowering high blood pressure unless other treatments have not worked. Alpha-blockers work by relaxing your blood vessels, making it much easier for blood to flow through them.

Common side effects of alpha-blockers include:

  • fainting spells when you first start the treatment
  • dizziness
  • headache
  • swollen ankles
  • tiredness

Useful links

High blood pressure (hypertension) puts extra strain on your heart and blood vessels.

If untreated, over time this extra pressure can increase your risk of a heart attack, stroke and kidney disease.

Cardiovascular disease

High blood pressure can cause many different diseases of the heart and blood vessels (medically known as cardiovascular diseases), including:

  • stroke: occurs when the blood supply to part of the brain is cut off through blockage or rupture of a blood vessel
  • heart attack: happens when the supply of blood to the heart is suddenly blocked
  • embolism: occurs when a blood clot or air bubble blocks the flow of blood in a vessel
  • aneurysm: occurs when a blood vessel wall bursts causing internal bleeding

Kidney disease

High blood pressure can also damage the small blood vessels in your kidneys and stop them from working properly.

This can cause a number of symptoms, including:

  • tiredness
  • swollen ankles, feet or hands (due to water retention)
  • shortness of breath
  • blood in your urine
  • urinating more often, particularly at night
  • itchy skin

Kidney disease can be treated using a combination of medication and food supplements.

More serious cases may require dialysis (a treatment where waste products are artificially removed from the body) or a kidney transplant.

Find out about how to prevent high blood pressure.

Glossary

Angina

Angina is chest pain caused by a reduced flow of blood to the heart, typically resulting from heart disease.

Arteries

Arteries are blood vessels that carry blood from the heart to the rest of the body.

Blood

Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.

Blood vessels

Blood vessels are the tubes in which blood travels to and from parts of the body. The three main types of blood vessels are veins, arteries and capillaries.

Brain

The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Heart

The heart is a muscular organ that pumps blood around the body.

Heart attack

A heart attack happens when there is a blockage in one of the arteries in the heart.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

High blood pressure can be prevented by eating heathily, maintaining a healthy weight, exercising regularly, drinking alcohol in moderation and not smoking.

Diet

Cut down on the amount of salt in your food and eat plenty of fruit and vegetables.

Salt raises your blood pressure. The more salt you eat, the higher your blood pressure. You should aim to eat less than less than 6g (0.2oz) of salt a day, about a teaspoonful.

Eating a low-fat diet that includes lots of fibre (for example, wholegrain rice, bread and pasta) and plenty of fruit and vegetables has been proven to help lower blood pressure. Fruit and vegetables are full of vitamins, minerals and fibre to keep your body in good condition. You should aim to eat five 80g portions of fruit and vegetables every day.

Alcohol

Regularly drinking alcohol above what the NHS recommends will raise your blood pressure over time. Staying within the recommended levels is the best way to reduce your risk of developing high blood pressure.

Alcohol is also high in calories, which will make you gain weight. This will also increase your blood pressure.

Caffeine

Drinking more than four cups of coffee a day may increase your blood pressure. If you are a big fan of coffee, tea or other caffeine-rich drinks (such as cola and some energy drinks), consider cutting down. It is fine to drink tea and coffee as part of a balanced diet but it is important that these drinks are not your only source of fluid.

Weight

Being overweight forces your heart to work harder to pump blood around your body, which can raise your blood pressure. Find out if you need to lose weight with the

If you do need to shed some weight, it is worth remembering that just losing a few pounds will make a big difference to your blood pressure and overall health.

Exercise

Being active and taking regular exercise lowers blood pressure by keeping your heart and blood vessels in good condition. Regular exercise can also help you lose weight, which will also help lower your blood pressure.

Adults should do at least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity (i.e. cycling or fast walking) every week. For it to count, the activity should make you feel warm and slightly out of breath. Someone who is overweight may only have to walk up a slope to get this feeling. Physical activity can include anything from sport to walking and gardening.

Relaxation therapies

Relaxation therapy and exercise can reduce blood pressure. These therapies include:

  • stress management, meditation or yoga
  • cognitive behaviour therapy (CBT), which focuses on how thoughts and beliefs can affect the way you feel and how you cope with problems.
  • biofeedback, where a small monitor constantly shows you your heartbeat or blood pressure, and is used to help you try to control your blood pressure.

These treatments are not normally provided by the HSE, although you may want to find out more about them for yourself. 

Smoking

Smoking does not directly cause high blood pressure but it puts you at much higher risk of a heart attack and stroke. Smoking, like high blood pressure, will cause your arteries to narrow. If you smoke and have high blood pressure, your arteries will narrow much more quickly and your risk of a heart or lung disease in the future is dramatically increased. Get help to QUIT smoking.


Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.