A stroke is a serious medical condition that occurs when the blood supply to the brain is disturbed.Introduction
Symptoms and signs of a stroke
Causes of a stroke
Diagnosing a stroke
Treating a stroke
Recovering from a stroke
Preventing a stroke
Complications of a stroke
IntroductionMost strokes are caused by blockages disrpting the brains blood supply..
Like all organs, our brain needs the oxygen and nutrients provided by our blood to function properly. If the supply of blood is restricted or stopped, brain cells begin to die. This can lead to brain damage and possibly death.
Strokes are a medical emergency, and prompt treatment is essential because the sooner a person receives treatment for a stroke, the less damage is likely to happen.
Types of stroke
There are two main causes of strokes:
- Ischaemic (accounting for 70% of all cases): the blood supply is stopped due to a blood clot.
- Haemorrhagic:a weakened blood vessel supplying the brain bursts and causes brain damage.
There is also a related condition known as atransient ischaemic attack (TIA), where the supply of blood to the brain is temporarily interrupted, causing a sort of 'mini-stroke'. TIAs should be treated very seriously as they are often a warning sign that afull stroke is coming.
Who's at risk from stroke?
In England, strokes are a major health problem. With over 111,000 people having a stroke every year, they are the third largest cause of death. The brain damage caused by strokes means that they are the largest cause of adult disability in the UK.
People who are over 65 years of age are most at risk from having strokes, although 25% of strokes occur in people who are under 65 years of age. It is also possible for children to have strokes.
Those of Afro-Caribbean origin are at increased risk of having a stroke, and the number of people affected by the condition is higher among this ethnic group than any other. This is because people of Afro-Caribbean origin have a genetic predisposition (a natural tendency) to developing diabetes and heart disease, which are two conditions that can cause strokes.
Smoking, obesity, poor diet and excessive alcohol consumption are also risk factors for stroke. Also, conditions that affect the circulation of the blood, such as diabetes or hypertension (high blood pressure), increase your risk of having a stroke.
Strokes can be treated and prevented
Strokes can usually be successfully treated and they can also be prevented. Following a healthy diet, taking regular exercise, drinking alcohol in moderation and not smoking will dramatically reduce your risk of having a stroke.
See the prevention section for more information about reducing the risk of having a stroke.
Strokes can be treated using a combination of surgery and medicines. However, many people will require a long period of rehabilitation after a stroke, and not all will recover fully.
Symptoms and signs of a stroke
If you suspect that you or someone else is having a stroke, you must phone 999 immediately andask for an ambulance.
Even if the symptoms of a stroke disappear while you are waiting for the ambulance to arrive, you (or they) should still go to hospital for an assessment because there is a risk that you may be about to have a full stroke.
After an initial assessment, you may need to be admitted to hospital to receive a more in-depth assessment and, if necessary,for specialist treatment to begin.
Recognising the signs and symptoms of a stroke
The signs and symptoms of a stroke vary from person to person, but they usually begin suddenly. As different parts of your brain control different parts of your body, your symptoms will depend upon the part of your brain that has been affected and the extent of the damage.
Themain stroke symptoms can be remembered with the word FAST: Face-Arms-Speech-Time.
- Face. The face may have fallen on one side, the person may not be able to smile, or their mouth or eye may have drooped.
- Arms. The person with suspected stroke may not be able to raise both arms and keep them there because of arm weakness or numbness.
- Speech. There may be slurred speech.
- Time. It is time to dial 999 immediately if you see any of these signs or symptoms.
If you live with or care for somebody in a high-risk group, such as someone who is elderly or has diabetes or high blood pressure, being aware of them is even more important.
Symptoms in the FAST test identify about nine out of10 strokes.
Other signs and symptoms may include:
- communication problems, difficulty talking and understanding what others are saying,
- problems with balance and coordination,
- difficulty swallowing,
- severe headaches,
- numbness/weakness resulting in complete paralysis of one side of the body, and
- loss of consciousness (in severe cases).
Recognising a stroke in other people
One of the problems with strokes is that people who are affected by them often have problems communicating with others. They therefore may not be able to raise an alarm or alert others to the fact that something is wrong.
Prompt emergency treatment for strokes is important because,typically, 1.9 million brain cells are lost during every minute a stroke goes untreated.
Also, one of the treatments for strokes called thrombolysis (where medicines are used to dissolve blood clots) mustbe given withinthree hours of the stroke happening.
'Mini-stroke' or transient ischaemic attack (TIA)
The symptoms of a transient ischaemic attack (TIA) are the same as for a stroke, but they only last from between a few minutes to a few hours,then completely disappear. However, never ignore a TIA as it is a serious warning sign that there is a problem with the blood supply to your brain.
There is about aone in fivechance that those who have a TIA will experience a full stroke during the four weeks following the TIA. If you have had a TIA, you should contact your GP, local hospital or out-of-hours service immediately, to arrange for a specialist assessment.
The Department of Health recommends that anyone who experiences a TIA receives a specialist assessment within seven days of the TIA. Some people have a higher risk of stroke after a TIA. This includes people:
- with diabetes,
- aged 60 or above,
- with high blood pressure (hypertension),
- who had TIA symptomsthat lasted for more than an hour, and
- who had both weakness in the body and problems with speech during a TIA.
The Department of Health recommends that anyone in those groups should receive a specialist assessment within 24 hours of having a TIA.
Causes of a stroke
Ischaemic strokes occur when blood clots block the flow of blood to the brain. Blood clots typically form in areas where the arteries have been narrowed or blocked by fatty cholesterol-containing deposits known as plaques. This narrowing of the arteries is known as atherosclerosis.
As we get older, our arteries become narrower, but certain risk factors can dangerously accelerate the process. Risk factors include:
- high blood pressure (hypertension),
- high cholesterol levels (often caused by a high-fat diet), and
- a family history of heart disease or diabetes.
Diabetes is also a risk factor, particularly if it is poorly controlled, because the excess glucose in the blood can damage the arteries.
Another possible cause of ischaemic stroke is an irregular heartbeat (atrial fibrillation), which can cause blood clots that become lodged in the brain. Atrial fibrillation can be caused by:
- high blood pressure,
- coronary artery disease,
- mitral valve disease (disease of the heart valve),
- cardiomyopathy (wasting of the heart muscle),
- pericarditis (inflammation of the bag surrounding the heart),
- hyperthyroidism (overactive thyroid gland),
- excessive alcohol intake, and
- drinking lots of caffeine - for example tea, coffee and energy drinks.
Haemorrhagic strokes occur when a blood vessel in the brain bursts. The main cause of this is high blood pressure (hypertension), which can weaken the arteries in the brain and make them prone to split or rupture.
The risk factors for high blood pressure include:
- being overweight,
- drinking excessive amounts of alcohol,
- a lack of exercise, and
- stress, which may cause a temporary rise in blood pressure.
A person's ethnic group can also be a risk factor for high blood pressure. Half of all people of black-African or Caribbean origin who are over 40 years of age are likely to have high blood pressure. Research has suggested this is because people of African origin have an increased sensitivity to the effects of salt, which can cause their blood pressure to rise.
A haemorrhagic stroke can also sometimes occur as a result of a traumatic head injury.
Around 5% of strokes are caused by a condition known as a subarachnoid haemorrhage. This condition differs from other causes of stroke because it involves defects in the brain that are present at birth.
Stroke affects many young people each year
While the main causes of strokeare similar to those of older people,in recovery young people will probably have different concerns about their family,theirfinances, and social and employment issues. The Stroke Association and Different Strokes offer specificadvice to help young people.
Diagnosing a stroke
Strokes are usually diagnosed by studying images of the brain (brain imaging). This can also be helpful in determining the risk of a transient ischaemic attack (TIA).
Even if the physical symptoms of a stroke are obvious, brain imaging should be carried out in order to determine whether an ischaemic stroke or a haemorrhagic stroke has occurred.
This is important because different treatment is required for each condition, and treating a haemorrhagic stroke with the methods used for an ischaemic stroke will make the condition worse.
CT and MRI scans
Two common methods that are used for brain imaging are a computer tomography (CT) scan and a magnetic resonance imaging (MRI) scan.
A CT scan is like an X-ray, but it uses multiple images to build up a more detailed, three-dimensional (3-D) picture of your brain. An MRI scan uses a strong magnetic field and radio waves to produce a detailed picture of the inside of your body.
A number of other tests will also be carried out to try and identify the cause of the stroke. These include:
- a blood pressure test,
- blood tests to measure factors such as your cholesterol level or, if you are diabetic, your glucose level, and
- an echocardiogram, which is an image of your heart that is produced using sound waves.
Treating a stroke
Ischaemic strokes can be treated using a 'clot-busting' medicine called alteplase, which dissolves blood clots. However, alteplase is only effective if used during the first three hours after a stroke has taken place. After that time, the medicine has no beneficial effects.
You will also be given a regular dose of aspirin, as this makes the cells in your blood, known as platelets, less sticky, reducing the chances of further blood clots occurring. If you are allergic to aspirin, other anti-platelet medicines are available.
You may also be given an additional medication called an anticoagulant. Like aspirin, anticoagulants prevent blood clots by changing the chemical composition of the blood in a way that prevents clots from occurring. Heparin and warfarin are two anticoagulants that are commonly used.
Anticoagulants are often prescribed for people who have an irregular heartbeat that can cause blood clots.
If your blood pressure is too high, you may be given medicines to lower it. Two medicines that are commonly used are:
- thiazide diuretic - this reduces the amount of water in your body and widens the blood vessels, which decreases blood pressure, and
- angiotensin converting enzyme (ACE) inhibitors, which widen the blood vessels and reduce blood pressure.
If the level of cholesterol in your blood is too high, you will be given a medicine known as a statin. Statins reduce the level of cholesterol in your blood by blocking an enzyme (chemical) in the liver that produces cholesterol.
Some ischaemic strokes are caused by a blockage in the carotid artery, which is an artery in the neck. The blockage, known as carotid stenosis, is caused by a build-up of fatty plaques.
If the carotid stenosis is particularly bad, surgery may be used to unblock the artery. This can be done using a surgical technique called a carotid endarterectomy, which involves the surgeon making an incision in your neck in order to open up the carotid artery and remove the fatty deposits.
Emergency surgery is often required to treat haemorrhagic strokes in order to remove any blood from the brain and repair any burst blood vessels. This is usually done using a surgical procedure known as a craniotomy.
During a craniotomy, a small section of your skull is cut away to allow the surgeon to gain access to the cause of the bleeding. The surgeon will repair any damaged blood vessels and will ensure that there are no blood clots present that may restrict the blood flow to your brain. After the bleeding has been stopped, the piece of bone removed from the skull is replaced.
Following a craniotomy, you may have to be placed on a ventilator. A ventilator is a machine that assists you with breathing. It gives your body time to recover by taking over its normal responsibilities, such as breathing, and it will also help control any swelling that you have in your brain.
You will also be given medicines, such as ACE inhibitors, to lower your blood pressure and prevent further strokes from occurring.
Transient ischaemic attack (TIA)
The treatment for a transient ischaemic attack involves addressing the conditions that led to it, while trying to prevent those conditions causing a bigger, more serious stroke.
If you have a TIA, the treatment that you receive will depend on what caused it, but you will typically be given one of the medicines outlined above, or a combination of them. So, if high blood pressure and high cholesterol levels put you at risk of having a stroke, you may be given a combination of statins and ACE inhibitors.
If the risk of a stroke is very high due to a build-up of fatty plaques in your carotid artery, a carotid endarterectomy may be required
Recovering from a stroke
The damage caused by a stroke can be widespread and long-lasting. Many people need to have a long period of rehabilitation before they can recover their former independence.
The process of rehabilitation will be specific to you, and will depend on your symptoms and their severity. A team of specialists are available to help, including physiotherapists, psychologists, occupational therapists, speech therapists and specialist nurses and doctors.
The damage that a stroke causes to your brain can impact on many aspects of your life and wellbeing, and depending on your individual circumstances, you may require a number of different treatment and rehabilitation methods. These are discussed in more detail below.
The two most common psychological conditions found in people after a stroke are:
- depression - many people experience intense bouts of crying and feel hopeless and withdrawn from social activities,
- anxiety disorder - many people experience general feelings of fear and anxiety, often punctuated by intense, uncontrolled feelings of anxiety (anxiety attack).
You should receive a psychological assessment within the first month of your stroke. Depression and anxiety can be treated using psychological therapies, such as counselling or cognitive behavioural therapy - a therapy that will aim to change the way you think about things in order to produce a more positive state of mind.
More severe cases of depression and anxiety may require additional treatment with medicines. The antidepressants known as selective serotonin reuptake inhibitors (SSRIs) are most commonly used to treat depression. Other types of antidepressants may be used if you cannot take SSRIs, or do not respond to treatment.
Anxiety disorders can be treated in the short term using medicines known as benzodiazepines. These medicines have potentially serious side effects, so can only be used for two weeks. After that time, antidepressants may be prescribed.
Talking about your experience and concerns for the future can be a great help in coming to terms with the psychological impact of a stroke.
'Cognitive' is a term used by scientists to describe the many processes and functions our brain uses to process information.
One or more cognitive functions can be disrupted by a stroke. Cognitive functions include:
- communication - both verbal and written,
- spatial awareness - having a natural awareness of where your body is in relation to your immediate environment,
- executive function - the ability to plan, problem solve and reason about situations, and
- praxis - the ability to carry out skilled physical activities, such as getting dressed or making a cup of tea.
As part of your treatment, each one of your cognitive functions will be assessed and a treatment and rehabilitation plan will be created.
You can be taught a wide range of techniques that can help you 're-learn' disrupted cognitive functions, such as recovering communication skills through speech therapy.
There are also many methods that can be used to compensate for any loss of cognitive function, such as using memory aids or a wall planner to help plan daily tasks.
Most cognitive functions will return after time and rehabilitation, but you may find that they do not fully return to their former levels.
Strokes can cause weakness or paralysis in one side of the body. Also, many people have problems with coordination and balance.
As part of your rehabilitation you should be seen by a physiotherapist, who will assess the extent of any physical disability before drawing up a treatment plan.
Treatment will normally begin as soon as your medical condition has stabilised. At first, your physiotherapist will work with you to improve your posture and balance.
After this, you will have short sessions of physiotherapy that last a few minutes. The sessions will then increase in duration as you start to regain muscle strength and control.
The physiotherapist will work with you by setting goals. At first, these may be simple goals like picking up an object. As your condition improves, more demanding long-term goals, such as standing or walking, will be set.
A member of your family, such as an unpaid carer, or a paid careworker,will be encouraged to become involved in your physiotherapy. The physiotherapist can teach you both simple exercises which you can carry out at home.
Sometimes, physiotherapy can last months or even years. The treatment is stopped when it is no longer producing any marked improvement to your condition.
After having a stroke, many people experience problems with speaking and understanding, as well as with reading and writing. This is called aphasia, and is sometimes also known as dysphasia.
Aphasia can be caused by damage to the parts of the brain that are responsible for language, but it can also be due to the muscles that are involved in speech being affected. You should see a speech and language therapist as soon as possible for an assessment, and to start therapy to help you with your communication skills.
Stroke can sometimes damage the parts of the brain that receive, process, and interpret information that is sent by the eyes. Some people may have double vision, or lose half of their field of vision. This means that they are able to see everything that is on one side, but are blind on the other.
Many people suffer from extreme tiredness (fatigue) in the first few weeks after a stroke, and may also have difficulty sleeping, making them even more tired.
If you have had a stroke, or transient ischaemic attack (TIA), you cannot drive for one month. Whether you can return to driving depends on what long-term disabilities you may have, and the type of vehicle that you drive.
Your GP will be able to advise you about whether you are able to start driving again a month after your stroke, or TIA, or whether you may need to have a further assessment at a mobility centre.
There are many ways that you can provide support to a friend or relative who has had a stroke in order to speed up their rehabilitation process. These are listed below.
- Help practice physiotherapy exercises in between their sessions.
- Provide emotional support and reassurance that their condition will improve with time.
- Help motivate the person to reach their long-term goals.
- Adapt to any needs they may have, such as speaking slowly if they have communication problems.
Caring for somebody after a stroke can be a frustrating and sometimes a lonely experience. The advice outlined below may help.
Be prepared for changed behaviour
Someone who has had a stroke can often seem as though they have had a change in personality, and they can sometimes appear to act irrationally. This is due to the psychological and cognitive impact of a stroke. They may become angry or resentful towards you. Upsetting as it may be, try not to take it personally. It is important to remember that a person will 'return to their old self' as their rehabilitation progresses.
Try to remain patient and positive
Rehabilitation can be a slow and frustrating process, and there will be periods of time when it appears that little progress has been made. Encouraging and praising any progress, no matter how small it may appear, can help motivate someone who has had a stroke to achieve their long-term goals.
Make time for yourself
If you are caring for someone who has had a stroke, it is important not to neglect your own physical and psychological wellbeing. Socialising with friends or pursuing leisure interests will help you cope better with the situation.
Ask for help
There are a wide range of support services and resources available for people who are recovering from strokes, and their families and carers. This ranges from equipment that can help with mobility, to psychological support for carers and families.
The hospital staff involved with the rehabilitation process will be able to provide advice and relevant contact information.
Preventing a stroke
The best way to prevent a stroke is to eat a healthy diet, exercise regularly, and avoid smoking and excessive consumption of alcohol.
A poor diet is a major risk factor for a stroke. High-fat foods can lead to the build-up of fatty plaques in your arteries, and being overweight can lead to high blood pressure.
A low-fat, high-fibre diet is recommended, including plenty of fresh fruit and vegetables (five portions a day) and whole grains. You should limit the amount of salt that you eat to no more than 6g (0.2oz) a day because too much salt will increase your blood pressure. 6g of salt is about one teaspoonful.
There are two types of fat - saturated and unsaturated. You should avoid food containing saturated fats because these will increase your cholesterol levels.
Foods high in saturated fat include:
- meat pies,
- sausages and fatty cuts of meat,
- ghee - a type of butter that is often used in Indian cooking,
- hard cheese,
- cakes and biscuits, and
- foods that contain coconut, or palm oil.
However, a balanced diet should include a small amount of unsaturated fat, which will actually help reduce your cholesterol levels.
Foods high in unsaturated fat include:
- oily fish,
- nuts and seeds,
- sunflower, rapeseed, olive and vegetable oils.
Combining a healthy diet with regular exercise is the best way to maintain a healthy weight. Having a healthy weight reduces your chances of developing high blood pressure.
Regular exercise will make your heart and blood circulatory system more efficient, it will lower your cholesterol level, and also keep your blood pressure at a healthy level.
The recommended level of cholesterol is 5 millimoles per litre of blood or 5mmol/litre. A millimole is a unit of measurement that is used by chemists and biologists to measure things that are extremely small.
Blood pressure is measured using two figures. One figure represents the pressure of the heart as it contracts to pumps blood around the body. This is known as the systolic pressure. The second figure represents the pressure of the heart as it expands and fills with blood, while waiting for the next contraction. This is known as the diastolic pressure.
For most people, a healthy blood pressure is a systolic pressure of 90-120 millimeters of mercury (mmHg) and a diastolic pressure of 60-80mmHg. Or, as blood pressure is normally expressed, a level between 90/60mmHG and 120/80mmHG.
For most people, 30 minutes of vigorous exercise a day at least five times a week is recommended. The exercise should be strenuous enough to leave your heart beating faster, and you should feel slightly out of breath. Examples of vigorous exercise are going for a brisk walk, or walking up a hill.
If you are recovering from a stroke, you should discuss possible exercise plans with the members of your rehabilitation team. Regular exercise may be impossible in the first weeks or months following a stroke, but you should be able to begin exercising once your rehabilitation has progressed.
Smoking is a major risk factor for strokes because it raises your blood pressure and can cause a build-up of fatty plaques in your arteries.
The NHS Smoking Helpline can offer you advice and encouragement to help you quit smoking. You can call on 0800 022 4 332, or visit the NHS Go smokefree website.
Your GP or pharmacist will also be able to provide you with help and advice about giving up smoking.
Excessive alcohol consumption can lead to high blood pressure and an irregular heartbeat (atrial fibrillation). Both are major risk factors for stroke.
Complications of a stroke
The damage caused by a stroke can interrupt your normal swallowing reflex, making it possible for small particles of food to enter your respiratory tract (your 'windpipe').
Problems with swallowing are known as dysphagia. Dysphagia can cause damage to your lungs, which can trigger a lung infection (pneumonia).
To prevent any complications from dysphagia, you may be fed through a feeding tube. The tube is usually put into your nose and then passed into your stomach, but it may be directly connected to your stomach during surgery.
How long you will need to have a feeding tube can vary from a few weeks to a few months, but it is very rare to have to use a tube for more than six months.
Hydrocephalus is a condition that occurs when there is too much cerebrospinal fluid in the ventricles (cavities) of the brain. About 10% of people who experience a haemorrhagic stroke will develop hydrocephalus.
Cerebrospinal fluid (CSF) is produced in the brain, and it protects the brain and spinal cord and carries away waste from brain cells. It flows continuously through the ventricles (cavities inside the brain) and over the surface of the brain and spinal cord. Any excess CSF usually drains away from the brain and is absorbed by the body.
The damage caused by a subarachnoid haemorrhage can stop the CSF from draining, and an excess of fluid can build up. Symptoms include:
- sickness and vomiting, and
- loss of balance.
However, the condition can be treated by placing a tube into the brain to allow the fluid to drain properly.
Deep vein thrombosis
Around 5% of people who have had a stroke will experience a further blood clot in their leg, known asdeep vein thrombosis (DVT).
This normally occurs in people who have lost some or all of the movement in their leg, as immobility will slow the blood flow in their veins, increasing blood pressure and the chances of a blood clot.
Symptoms of a DVT include:
- warm skin,
- tenderness, and
- redness, particularly at the back of the leg, below the knee.
If you have a DVT, prompt treatment is required because there is a chance that the clot may move into your lungs, which is known as a pulmonary embolism and can be fatal.
DVTs can be treated using anti-clotting medicines. If it is felt that you are at risk of a DVT, your stroke team may recommend that you wear a compression stocking - a specially designed stocking that can reduce the blood pressure in your legs.