What is a stroke?

An older man and woman talking together on a couch.
An older man and woman talking together on a couch.
A stroke is a medical emergency that occurs when blood flow to the brain is interrupted. When that happens, brain cells can be deprived of oxygen, potentially causing permanent damage. The impact stroke has on cognition, speech, and movement will depend on which areas of the brain have been affected and for how long. The sooner treatment is undertaken, the greater the chance of limiting impairment.

Types of stroke

There are 3 main types of stroke: Ischemic, haemorrhagic, and Transient Ischaemic Attack (TIA) or ‘mini-stroke’. There are also cryptogenic strokes and brainstem strokes. Strokes can also be recurrent, and these are usually ischemic strokes.

Ischemic stroke

This is the most common kind of stroke. It’s caused by a blockage in the artery supplying blood to the brain.

Haemorrhagic stroke

This type of stroke occurs when a blood vessel leaks or bursts and blood flows into or around the brain, preventing oxygen from reaching surrounding brain cells.

The 2 sub-types of haemorrhagic stroke are:

  • Intracerebral haemorrhage (ICH): when a bleed occurs in the brain itself due to a burst artery inside the brain.
  • Subarachnoid haemorrhage (SAH): occurs as a result of bleeding on the surface between the two membranes that cover the brain.

Transient ischaemic attack (TIA)

Transient Ischaemic Attack (TIA) or a ‘mini stroke’ is the same as a stroke, except that the symptoms are short-lived because the interruption of blood flow to the brain is temporary.

Unlike a stroke, TIA has no lasting impact on the ability to walk, move, talk, swallow or see. It’s important to note that TIA or mini strokes can lead to a major stroke, especially in the hours and days after. To reduce the risk of a major stroke, always get treatment as soon as possible.

Cryptogenic stroke

Strokes without a known cause are called cryptogenic strokes.

Brainstem stroke

This stroke occurs in the brainstem and can affect both sides of the body, leaving the person in a ‘locked-in’ state. This kind of stroke can be hard to diagnose and may include symptoms of vertigo and dizziness.

What causes a stroke?

A stroke can occur at any age. Different types of strokes have different causes. Factors such as age, family history and gender also play a role in a person’s risk of a stroke.

Ischaemic strokes are caused when blood clots block the flow of blood and, therefore, oxygen to the brain. While atrial fibrillation—an irregular heart rhythm—can cause blood clots in the heart, clots more typically form in arteries that have narrowed or become blocked due to fatty deposits.

Haemorrhagic strokes are usually caused by high blood pressure, which can weaken arteries and make them susceptible to damage.

Haemorrhagic strokes can also be caused by head injuries, aneurysms or — less commonly — an abnormally formed blood vessel.

Cryptogenic strokes have an undetermined cause.

Brainstem strokes are mostly considered ischemic – they are caused by a blood clot that blocks the flow of blood to the brain.

Reassuringly, more than 80% of strokes are preventable.

Learn more about how strokes can be prevented.

Stroke risk factors to consider

Our arteries can naturally narrow as we age. However, there are specific conditions and health choices that can increase this risk a,s well as increase blood pressure:

  • Obesity
  • High cholesterol
  • Stress
  • Diabetes
  • Smoking
  • Heavy drinking
  • A high-salt and high-fat diet
  • Lack of exercise.

What are the warning signs of stroke?

The Stroke Foundation recommends using the F.A.S.T. (Face, Arms, Speech, Time) test if you suspect you or someone else may be having a stroke.

Face – Check their face. Has their mouth drooped?

Arms – Can they lift both arms?

Speech – Is their speech slurred? Do they understand you?

Time – Is critical. If you see any of these signs, call 000 straight away.

The above symptoms are the most common signs of a stroke but are not the only ones. The following may also occur alone or in combination:

  • Severe headache, usually with abrupt onset or unexplained change in the pattern of headaches
  • A sudden feeling of numbness or weakness in your face or limbs, particularly on one side
  • Confusion, trouble communicating or understanding others
  • Difficulty seeing
  • Problems swallowing
  • Loss of balance or coordination and dizziness.

If you think you or someone else may be experiencing a stroke, the key is to act FAST– call 000 immediately.

Learn more about the warning signs of stroke and how to help someone having a stroke.

What happens after a stroke?

All strokes are different – some people may recover fairly quickly, while others may experience significant disability and may need long-term support.

Following a stroke, a brain scan is typically conducted, and based on factors such as the type of stroke, the time elapsed since it occurred, and individual risk factors, either clot-busting medications are given or a clot retrieval procedure may be performed.

How long a person remains in the hospital is dictated by the type of stroke, its severity, the treatment received, progress in recovery, and the bigger picture of a person’s general health.

While no medical treatment can repair brain damage caused by stroke, rehab can help people relearn or find new ways of doing things. Rehabilitation leans on the principles of neuroplasticity, which is the nervous system’s inherent ability to reorganise its connections and functions. In short, it’s about using new parts of the brain to compensate for the areas impacted by stroke.

While improvement may continue for years, rehabilitation tends to yield the greatest results in the early months following a stroke. As ever, speed is of the essence – engage with specialists as quickly as possible, hoping to minimise the effects as much as possible.

Getting NDIS support for a stroke

According to data from the Stroke Foundation in 2022, more than 445,087 Australians are living with the effects of stroke, a leading cause of disability in the country. A significant stroke can result in permanent disability.

If you or someone you know has experienced a stroke, you may be eligible for NDIS funding or aged care funding.

Once approved for NDIS funding or Home Care Package funding, you can engage independent support workers through Mable and access in-home support services.

Learn more about eligibility for NDIS funding following a stroke.

FAQs

The cause of stroke varies, depending on the type you experience – ischaemic or haemorrhagic – although there are common risk factors, including smoking, poor diet, lack of exercise, heavy drinking, high cholesterol and high blood-pressure.

If you have previously experienced a stroke or TIA, it's particularly important to be vigilant and to actively manage any risk factors with medical practitioners, as the chances of having another stroke may have greatly increased.

Every stroke is different but typically a stroke is not painful at the time. However, some people do experience pain during treatment and recovery.

Stress can trigger a range of risk factors for stroke, including poor diet, a sedentary lifestyle, smoking and reliance on alcohol. It can also cause the heart to work harder, which increases blood pressure, and drives up sugar levels in the blood, potentially triggering diabetes – all factors which can increase the risk of clots. Similarly, stress is known to increase inflammation in the arteries and throughout the body, narrowing blood vessels and inhibiting blood supply, and therefore oxygen, to the brain.

Unfortunately, there is no clear or predictable timeline. Recovery will depend upon the severity of the stroke, the areas of the brain affected, and the speed of access to treatment and rehabilitation.

It's important to note that stroke can happen to anyone at any age. As we get older, our risk increases. According to information from the Stroke Foundation, men are also statistically at higher risk. Other factors such as family history, heart conditions, blood vessel problems and disorders, genetic disorders, autoimmune conditions and lifestyle factors can also significantly increase the risk of stroke.

According to the Victor Change Cardiac Research Institute, family history plays a significant role in determining a person's risk of stroke but not all strokes are hereditary. It's important to note that many other factors contribute to the risk of having a stroke.

Atrial fibrillation (AF) is a risk factor for stroke because blood does not move through the heart completely, according to the Stroke Foundation. As a result, a clot can form in the heart. If that clot breaks away and travels to the brain, it may cause a stroke. AF is associated with one in four strokes.

The effects of a stroke on the brain depend on which area of the brain the stroke occurred and, therefore, which functions will be impacted. According to the Stroke Foundation, depending on which area of the brain is affected, you might experience weakness on one side of the body, problems coordinating movements, difficulty swallowing, personality changes, challenges with speaking and more.

Dementia Australia explores vascular dementia, a type of dementia caused from damage to the brain often led by strokes and other vascular issues. Having a stroke more than doubles your risk of developing dementia due to the damage caused by a restriction of blood flow (oxygen) to the brain. The restricted blood flow and supply to the brain is usually due to clogged blood vessels caused by a stroke or a series of small strokes. For more information about the relationship between a stroke and dementia, you can also visit the Dementia Australia website.

Synapse, known as Australia's Brain Injury Organisation, states that the effects of a stroke vary widely from case to case, and may have left and right hemisphere effects.

The information provided in this article is general information only. In the event that you or someone else you know has a stroke, Mable encourages you to seek your own independent medical advice about strokes.