Introduction 

A stroke is a serious, life-threatening medical condition that occurs when the blood supply to part of the brain is cut off.

Strokes are a medical emergency and urgent treatment is essential because the sooner a person receives treatment for a stroke, the less damage is likely to happen.

 

Signs and symptoms

The main symptoms of stroke can be remembered with the word FAST: Face-Arms-Speech-Time.

 

 

 

• Face – the face may have dropped on one side, the person may not be able to smile or their mouth or eye may have dropped.

• Arms – the person with suspected stroke may not be able to lift both arms and keep them there because of arm weakness or numbness in one arm.

• Speech – their speech may be slurred or garbled, or the person may not be able to talk at all despite appearing to be awake.

• Time – it is time to dial emergency serviices immediately if you see any of these signs or symptoms.

• Symptoms in the FAST test identify most strokes, but occasionally a stroke can cause different symptoms.

  Other symptoms and signs may include:

• complete paralysis of one side of the body

• sudden loss or blurring of vision 

• However, there are usually other causes for these symptoms.

• dizziness

• confusion

• difficulty understanding what others are saying

• problems with balance and co-ordination 

• difficulty swallowing (dysphagia)

• a sudden and very severe headache resulting in a blinding pain unlike anything experienced before

• loss of consciousness

 

Why do strokes happen?

Like all organs, the brain needs the oxygen and nutrients provided by blood to function properly. If the supply of blood is restricted or stopped, brain cells begin to die. This can lead to brain injury, disability and possibly death.

There are two main causes of strokes:

1. ischaemic – where the blood supply is stopped due to a blood clot (this accounts for 85% of all cases) haemorrhagic – where a weakened blood vessel supplying the brain bursts

2. There is also a related condition known as a transient ischaemic attack (TIA), where the supply of blood to the brain is temporarily interrupted, causing a 'mini-stroke' often lasting between 30 minutes and several hours. TIAs should be treated seriously as they are often a warning sign that you are at risk of having a full stroke in the near future. 

   The symptoms of a TIA are the same as a stroke, but they tend to only last between a few minutes and a few hours before disappearing completely.

   Although the symptoms do improve, a TIA should never be ignored as it is a serious warning sign there is a problem with the blood supply to your brain and means you are at an increased risk of having a stroke in the near future.

 

Ischaemic strokes

Ischaemic strokes are the most common type of stroke. They occur when a blood clot blocks the flow of blood and oxygen to the brain.

These blood clots typically form in areas where the arteries have been narrowed or blocked over time by fatty deposits known as plaques. This process is known as atherosclerosis.

As you get older, the arteries can naturally narrow, but certain things can dangerously accelerate the process. These include:

• smoking 

• high blood pressure (hypertension) 

• obesity 

• high cholesterol levels

• diabetes 

• an excessive alcohol intake

Another possible cause of ischaemic stroke is a type of irregular heartbeat called atrial fibrillation, which can cause blood clots in the heart that break up and escape from the heart and become lodged in the blood vessels supplying the brain.

Atrial fibrillation can have a number of different causes, including lung disease, heart valve disease, excessive alcohol intake, coronary heart disease, and an overactive thyroid gland  (hyperthyroidism). Read more about the causes of atrial fibrillation.

 

Haemorrhagic strokes

Haemorrhagic strokes (also known as cerebral haemorrhages or intracranial haemorrhages) are less common than ischaemic strokes. They occur when a blood vessel within the skull bursts and bleeds into and around the brain.

The main cause of haemorrhagic stroke is high blood pressure, which can weaken the arteries in the brain and make them prone to split or rupture.

Things that increase the risk of high blood pressure include:

• being overweight or obese

• drinking excessive amounts of alcohol 

• smoking

• a lack of exercise 

• stress, which may cause a temporary rise in blood pressure

Haemorrhagic strokes can also occur as the result of the rupture of a balloon-like expansion of a blood vessel (brain aneurysm) and badly-formed blood vessels in the brain.

 

Who is at risk?

Strokes are a major health problem in the world. Every year, around hundreds of thousands of people have a stroke in the world and it is the third largest cause of death, after heart disease and cancer. The brain injuries caused by strokes are a major cause of adult disability .

Older people are most at risk of having strokes, although they can happen at any age – including in children.

If you are south Asian, African or Caribbean, your risk of stroke is higher. This is partly because of a predisposition (a natural tendency) to developing high blood pressure (hypertension), which can lead to strokes.

Smoking, being overweight, lack of exercise and a poor diet are also risk factors for stroke, as are high cholesterol, atrial fibrillation anddiabetes.

 

Can I reduce my risk?

It's not possible to completely prevent strokes because some things that increase your risk of the condition cannot be changed, including:

• age – you are more likely to have a stroke if you are over 65 years old, although about a quarter of strokes happen in younger people

• family history– if a close relative (parent, grandparent, brother or sister) has had a stroke, your risk is likely to be higher

• ethnicity – if you are south Asian, African or Caribbean, your risk of stroke is higher, partly because rates of diabetes and high blood pressure are higher in these groups

• your medical history – if you have previously had a stroke,transient ischaemic attack (TIA) or heart attack, your risk of stroke is higher

However, in most cases it is possible to significantly reduce your risk of having a stroke by making lifestyle changes to avoid problems such as atherosclerosis and high blood pressure. This includes things such as having a healthy diet, exercising regularly, stopping smoking if you smoke and cutting down on the amount of alcohol you drink.

As atrial fibrillation can also significantly increase your risk of having a stroke, it is also important to seek medical advice if you think you may have an irregular heartbeat. If you are diagnosed with the condition, you should talk to your doctor about the option of taking anticoagulant medications to lower your stroke risk.

 

Preventing strokes 

The best way to help prevent a stroke is to eat a healthy diet, exercise regularly and avoid smoking and drinking too much alcohol.

These lifestyle changes can reduce your risk of problems such as atherosclerosis (where arteries become clogged up by fatty substances), high blood pressure and high cholesterol levels, all of which are important risk factors for strokes.

If you have already had a stroke, making these changes can help reduce your risk of having another one in the future.

 

Diet

An unhealthy diet can increase your chances of having a stroke because it may lead to an increase in your blood pressure and cholesterol levels.

Therefore, a low-fat, high-fibre diet is usually recommended, including plenty of fresh fruit and vegetables (five portions a day) and whole grains.

Ensuring a balance in your diet is important. Don’t eat too much of any single food – particularly foods that are high in salt and processed foods.

You should limit the amount of salt you eat to no more than 6g (0.2oz) a day because too much salt will increase your blood pressure. Six grams of salt is about one teaspoonful.

 

Exercise

Combining a healthy diet with regular exercise is the best way to maintain a healthy weight, and regular exercise can also help lower your cholesterol level and keep your blood pressure at a healthy level.

For most people, at least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity, such as cycling or fast walking, every week is recommended.

If you are recovering from a stroke, you should discuss possible exercise plans with the members of your rehabilitation team. Regular exercise may not be possible in the first weeks or months following a stroke but you should be able to begin exercising once your rehabilitation has progressed.

 

Stop smoking

Smoking significantly increases your risk of having a stroke. This is because it narrows your arteries and makes your blood more likely to clot.

If you stop smoking, you can reduce your risk of having a stroke. Not smoking will also improve your general health and reduce your risk of developing other serious conditions, such as lung cancer and heart disease.

 

Cut down on alcohol

Excessive alcohol consumption can lead to high blood pressure and trigger irregular heartbeat (atrial fibrillation), both of which can increase your risk of having a stroke.

Because alcoholic drinks are high in calories they also cause weight gain. Heavy drinking multiplies the risk of stroke by more than three times.

If you choose to drink alcohol and have fully recovered, you should aim not to exceed the recommended limits. These are:

• men should not regularly drink more than 3-4 units of alcohol a day

• women should not regularly drink more than 2-3 units a day

If you have not fully recovered from your stroke, you may find that you will have become particularly sensitive to alcohol and even the recommended safe limits as above for the general population may be too much for you. 

 

Managing underlying conditions

If you have been diagnosed with a condition known to increase your risk of stroke – such as high cholesterol, high blood pressure, atrial fibrillation, diabetes or a transient ischaemic attack (TIA) – ensuring the condition is well controlled is also important in helping prevent strokes.

The lifestyle changes mentioned above can help control these conditions to a large degree, but you may also need to take regular medication.

 

How strokes are treated

Treatment depends on the type of stroke you have, including which part of the brain was affected and what caused it.

Most often, strokes are treated with medication. This generally includes medicines to prevent and remove blood clots, reduce blood pressure and reduce cholesterol levels.

In some cases, surgery may be required to treat brain swelling and reduce the risk of further bleeding in cases of haemorrhagic strokes.

 

Life after a stroke

Around one in every four people who has a stroke will die, and those who do survive are often left with long-term problems resulting from the injury to their brain.

Some people need to have a long period of rehabilitation before they can recover their former independence, while many will never fully recover and will need support adjusting to living with the effects of their stroke.

Around half the people who have a stroke will be dependent on some form of care for help with their daily activities.

The process of rehabilitation will be specific to you, and will depend on your symptoms and how severe they are. A team of specialists are available to help, including physiotherapists, psychologists, occupational therapists, speech therapists and specialist nurses and doctors.