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Stroke and high blood pressure


By lowering your blood pressure and making changes to your lifestyle, you can lower your risk of having a stroke.

High blood pressure is the single biggest cause of stroke. While many people don’t know that stroke can be prevented, the reality is much brighter. Recent research found that nine out of 10 strokes are preventable. By lowering your blood pressure and making changes to your lifestyle, you can lower your risk of having a stroke.

If you think you or someone you’re with might be having a stroke, call 999 straight away. Getting treatment quickly helps to prevent or keep long-lasting damage to a minimum.


What is a stroke?

A stroke is where the blood supply to part of the brain is cut off, and some cells may be damaged or even die as they’re not getting enough oxygen. The effects can be very sudden and even life-threatening.

There are two main types of stroke:

  • Ischaemic stroke – where a blood clot blocks a blood vessel leading to the brain. This is the most common type of stroke
  • Haemorrhagic stroke - where a blood vessel in the brain becomes weaker and bursts. These are usually caused by high blood pressure


What are the signs and symptoms of stroke?

Call 999 if you’re worried that you or someone you’re with is having a stroke. A stroke is a medical emergency and needs to be treated straight away, even if the symptoms disappear quickly.

Remember F.A.S.T. which stands for Face, Arms, Speech, Time, to recognise if someone is having a stroke.

Face – has their face fallen on one side? Can they smile?

Arms – can they raise both arms and keep them there?

Speech – is their speech slurred?

Time to call 999 if you see any single one of these signs of a stroke.

The NHS and The Stroke Association both have more information on stroke and how to Act F.A.S.T.


A stroke can sometimes have the following symptoms too:

  • a sudden and extremely painful headache
  • feeling confused
  • feeling dizzy or unsteady or losing co-ordination
  • slurring words or struggling to find words or put sentences together
  • struggling to understand what people are saying
  • sudden loss of vision or blurred vision
  • being paralysed (unable to move) or feeling numb or weak on one side of the body
  • difficulty swallowing

How does high blood pressure cause stroke?

Uncontrolled high blood pressure can damage your blood vessels. Over time, they can become narrower and stiffer, or weaker, which means they can get blocked or burst. This stops blood from reaching part of the brain, cutting off the supply of oxygen.

What else causes stroke?

Other health problems
There are a number of health problems which raise your risk of stroke. These include:

  • high cholesterol – which can cause a build-up of fat in the arteries, called atherosclerosis, making them narrower and leading to blood clots
  • diabetes – which can damage your blood vessels
  • being overweight or obese
  • atrial fibrillation – which is a type of irregular heartbeat which can cause blood clots to form in the heart which can travel to the brain


A number of lifestyle factors can also raise your risk of stroke, such as smoking, drinking a lot of alcohol, lack of exercise and stress – which can cause a temporary rise in blood pressure. 


Other risk factors
A number of other factors which you can’t change can also put you at a higher risk: 

  • age – being over 65 years of age
  • a family history of stroke – if a close relative has had a stroke, namely a parent, grandparent, brother or sister
  • being of Asian, African or Caribbean descent
  • having had a TIA, stroke or heart attack in the past

Even though some of these can’t be changed, you can still lower your risk of stroke by making changes to your lifestyle which improve your overall health, in fact, these lifestyle changes become even more important.


What is a TIA?

TIA stands for Transient Ischaemic Attack. A TIA is a mini or temporary stroke, when the blood supply to the brain is cut off for a short time, and the blockage clears and the symptoms disappear. The symptoms are similar to a stroke, but they don’t last as long, usually between a few minutes and few hours, and less than 24 hours.

If you notice the signs of stroke, never wait to see if the symptoms get better as it’s impossible to know how long they will last.

A TIA is a warning sign that you might be much more likely to have a full stroke in the near future. If you think you have had a TIA in the past but the symptoms have gone, make an urgent appointment with your GP.


How is stroke diagnosed?

A stroke is a medical emergency, and as soon as you arrive at the hospital, the team will want to find out as much as they can to see if you have had a stroke and what caused it. This will help them decide on the best treatment.

You will have your blood pressure measured and your pulse checked to see if you have an irregular heartbeat, and blood tests to check your blood cholesterol and sugar levels. 

You may also have scans of your brain. These help the team to see which part of the brain is affected, and whether the cause was a burst blood vessel or a blocked artery. The scans usually used are:

  • CT scan – which is similar to an X-ray but more detailed and gives a 3D image
  • MRI scan – this gives a very detailed 3D image which is taken in a large tunnel-shaped scanner and tends to be used in people with more complex symptoms

A number of other tests may be done later which can help the team to tailor your treatment. For example, a swallow test to see if you can swallow food and drink safely, a mobility test to see how well you can move around, and a number of other tests on your heart and blood vessels.


How are strokes treated?

Getting treatment quickly can prevent long-term problems and prevent another stroke from happening in the future. The treatments you have will depend on the type of stroke you had.

If your stroke was caused by a blocked artery
Treatments often include medications to break up blood clots and prevent other blood clots from forming, medications to lower blood pressure and cholesterol, and surgery to unblock arteries.

If it was caused by a burst blood vessel
You may need surgery to repair the damage, remove the blood and relieve any pressure that has built up. You may also be given medications to lower your blood pressure.


Recovering from a stroke

Some people recover quickly from a stroke, while others will have long-term problems and need ongoing support.

The effects include problems with movement and balance, vision, swallowing, controlling your bladder and bowels, and extreme tiredness. There can be changes in your emotions, problems communicating, and some people will have difficulties with memory and thinking (vascular dementia).

There is ongoing support available to help you recover and regain as much independence as possible. This often starts in hospital and continues at home or in a clinic after you leave.

A team of health professionals will help you to recover and to prevent another stroke. This will often be a specialist stroke team and can include, for example, doctors, nurses, physiotherapists, speech therapists, dietitians, occupational therapists and psychologists.

NHS Choices and Stroke Association have more information.


How can I lower my risk of stroke?

Many strokes are preventable and it’s possible to lower your risk of having a stroke by making healthy changes to your lifestyle and getting treatment for health problems which are linked to stroke.

Healthy changes to your lifestyle
There are healthy changes you can make to your lifestyle to lower your blood pressure and your risk of stroke. In particular, stopping smoking, watching what you drink, getting active, keeping to a healthy weight and eating healthily, for example by eating less salt and saturated fat and more fruit, veg and wholegrains

Treatment for health problems
It’s important to find out if you have any existing medical problems and get treatment and advice to make sure they are well controlled, including type 2 diabetes, high cholesterol, and heart problems such as atrial fibrillation and atrial flutter – where the heart beat is too fast or irregular. Atrial fibrillation often has no symptoms so you might not be aware of it, and treatment with medications greatly reduces the risk of stroke.

Visit your GP to have your blood pressure, pulse and cholesterol checked and ask about the health of your heart and your risk of diabetes. You can also have an NHS Health Check .


Read more 
NHS Choices 
NHS Choices  has lots more information about stroke, its causes, the treatments and information on recovering from a stroke.

Stroke Association
Stroke Association has information on stroke and it’s causes and treatments, information on life after stroke, including returning to work and driving, as well as how to find support as you recover, including services in your area, a helpline, and a forum for sharing experiences.


Real stories
Read the stories of people who’ve experienced stroke first hand, and how they’ve recovered. 

The battle’s not over until it’s won
Christine was determined to recover after her stroke. She learned how to walk again, went to college on crutches and learned how to cut the salt out of her Caribbean and West African-inspired diet. If you saw her now, you wouldn’t know she’d had a stroke.

My stroke changed my life for the better
Jon was only 39 when he had a stroke. After six months off work recovering, he completely changed his life – hitting the gym and running 10k races. He’s now fitter and healthier than ever and takes his blood pressure monitor into work to encourage others to know their numbers.

I want people to take more care of their blood pressure 
When Frances had a stroke at the age of 50, she lost the movement on her left-hand side. A year on, she’s able to walk again but her stroke has had a dramatic impact on her life.  Now, she’s speaking out to prevent stroke and has managed to encourage others to take more care of their blood pressure.




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