There are two types of stroke: ischaemic and haemorrhagic. Find out what causes each type, the common symptoms, and how stroke is diagnosed and treated.
A stroke (also known as a cerebral infarction) is a serious medical condition that needs urgent attention.
A stroke happens if the brain doesn’t receive the blood supply it needs, which in turn restricts oxygen in the brain. When this happens, it is usually because either the blood supply to the brain is blocked or a blood vessel in the brain bursts.
Without emergency treatment, clusters of cells in the brain can be damaged or die as a result of the lack of oxygen. This can lead to disability or even death. The sooner the right treatment is received, the better the chance of recovery.
There are two main types of stroke:
Some people experience a TIA before having a full stroke. The symptoms of a TIA are the same as a stroke, but they only last for a short time, which is why a TIA is often referred to as a ‘mini stroke’. Although the effects of a TIA aren’t as long lasting as a full stroke, it does indicate an increased risk of stroke in the near future.
The 2020 Burden of Stroke in Europe report found that there were 1.2 million strokes in the European Union in 2017. It also projected that the number of people living with stroke in the next three decades (2017–2047) would increase by 27%, mainly due to an ageing population and increased survival rates.
The main symptoms of stroke affect the face, arms, and speech. But stroke is different for everyone and the symptoms will depend on which part of the brain has been affected and how badly the brain tissue is damaged.
The three main areas of the body that are affected by stroke are:
Other possible symptoms may include:
There are no set stages associated with having a stroke; however, some people experience a transient ischaemic attack (TIA), which can be a warning sign that they may soon have a stroke. A TIA is sometimes called a ‘mini stroke’ because the symptoms are the same as those of a stroke but, because the blockage of blood to the brain is temporary, it only lasts for a short time.
A TIA does not damage the brain cells or cause permanent disability, but it does indicate an increased risk of having a full stroke in the near future.
Not everyone who has a stroke experiences a TIA first – but if they do, it’s important to get medical help immediately, as it could be a sign that a stroke is coming. In a study of stroke patients published in the medical journal Neurology, 2,416 people who had experienced an ischaemic stroke were examined. Of these, 549 experienced a TIA before their stroke, with the majority taking place within seven days of the stroke.
Symptoms of TIA include:
In the long term there are a number of mental and physical issues that can arise as a result of having a stroke. These include:
Strokes can be ischaemic (when the blood supply to the brain is cut off) or haemorrhagic (when there is bleeding in or around the brain). The chance of having a stroke increases with age, and older people have a lower chance of survival.
Strokes are caused by a restriction in blood supply to the brain, which happens in different ways depending on the type of stroke.
In ischaemic strokes, a blockage cuts off the blood supply to the brain. This can be caused by a blood clot forming either in an artery that leads to the brain or in a small blood vessel deep inside the brain. It can also be the result of a clot moving through the bloodstream to the brain from another part of the body.
A haemorrhagic stroke is also referred to as a brain haemorrhage or a brain bleed, as it is caused by bleeding in or around the brain. This can happen in two ways:
The risk of having a stroke is affected by factors which are either ‘non-modifiable’, meaning they cannot be changed, or ‘modifiable’, meaning behaviour and choices can influence them.
The two non-modifiable factors – those that relate to who a person is – that can affect the risk of having a stroke are:
Modifiable risk factors – those that can be influenced or controlled – include:
Heart disease is also a significant risk factor in having a stroke, and is a major cause of death after experiencing a stroke. If the heart disease is hereditary, this may be a non-modifiable risk factor, but some people may be able to modify their behaviour to influence their risk of heart disease, and therefore the risk of stroke.
When it comes to survival rates after a stroke, age is one of the most influential factors, with research showing that the risk of death from a stroke approximately doubles with every decade of age. Another significant factor is the length of time since the stroke. One study associated stroke with an almost fivefold increase in the risk of death between four weeks and one year after a stroke, compared with the general population, and a two-fold increase after one year.
However, survival rates have greatly improved over the last decade thanks to new stroke treatments and improved stroke care. Prompt treatment helps to increase the chance of survival and reduce the risk of long-term effects.
To give the best chance of recovery, doctors need to confirm the diagnosis of a stroke as quickly as possible.
Diagnosis is made by carrying out a range of tests to help identify any health conditions that can cause a stroke (such as high blood pressure) and performing brain scans to give a better picture of what is happening inside the brain.
If doctors suspect a stroke, they will try to carry out one of the following types of brain scan within an hour of arrival at hospital:
Other tests that can be helpful in diagnosing a stroke include:
Rehabilitation and recovery after a stroke take time. The process is different for everyone, and usually involves a team of specialists setting goals to work towards. It’s important to stay actively engaged in the rehabilitation plan for the best possible chance of recovery.
Every stroke is different, so treatment and recovery vary greatly between individuals. Recovery often takes months and can take years for some stroke survivors. It starts in hospital and often involves a range of specialists who will help set goals to work towards as part of recovery.
This may involve further tests to help doctors understand what is needed. Tests could include:
There are many simple lifestyle changes that can help reduce the risk of stroke:
A raft of research is being done to develop new and more effective treatments for stroke, and scientists are especially keen to discover ways to restore blood flow to the brain and protect brain cells from dying after a stroke. Other areas of interest in the field of treatment include looking at ways to improve rehabilitation and post-stroke recovery.
When it comes to stroke prevention, researchers are looking to understand more about the risk factors for stroke. Imaging techniques are also being used in an effort to learn more about how stroke affects the brain.
Shavelle R, Brooks J, Strauss D, Towfighi A. Long-term survival prognosis after stroke.
A practical guide for clinicians. Practical Neurology. Published February 2020. Accessed February 2021. https://practicalneurology.com/articles/2020-feb/long-term-survival-prognosis-after-stroke