Understanding stroke: Causes, types and prevention

Every 19 minutes, one Australian will experience their first stroke,¹ a sudden and life-altering event. Imagine sitting across from someone who suddenly loses their ability to speak or move their arm. This is the reality of stroke, one of our nation's biggest killers and a leading cause of disability.

But knowledge is power. Understanding what a stroke is, how to spot the signs and what action to take can save a life, whether it's yours or someone you love.

A stroke is when blood flow to the brain is interrupted, which prevents oxygen and nutrients from reaching it, killing brain cells. This can happen in 3 ways:

• blocked artery: A blood clot or plaque (cholesterol that builds up in the artery) blocks a blood vessel and stops blood flow to the brain
• bleed in the brain: A blood vessel in the brain bursts and causes blood to leak into surrounding tissue
• blood clots: A clot that forms elsewhere in the body travels to the brain and causes a blockage.

Without immediate treatment, the brain cells begin to die, leading to permanent damage or even death. Think of it like a power outage in your body's control centre; the quicker the power is restored, the less damage there is.

This is the most common type of stroke and is caused by blockages in the brain's blood vessels. There are 2 types of ischaemic strokes:

• embolic: A clot that travels through the blood stream and gets stuck in a narrow brain artery
• thrombotic: A build-up of plaque in the brain's arteries over time that eventually blocks blood flow.

This occurs when a blood vessel in the brain bursts, leading to bleeding (haemorrhage) in or around the brain. It's usually caused by chronic hypertension and conditions like an aneurysm.

Often called a 'mini-stroke', a TIA is a temporary blockage that resolves on its own within a few minutes or hours. While a TIA may cause temporary stroke-like symptoms, it's different from a stroke as it doesn't damage brain cells or cause permanent disability.

It is, however, a serious warning sign of a future stroke and shouldn't be ignored.

The faster a stroke is recognised and treated, the better the outcome. Use the F.A.S.T. test to identify the warning signs:

• Face: Is one side of the face drooping?
• Arms: Can the person raise both arms?
• Speech: Is their speech slurred or strange?
• Time: Call emergency services immediately if you notice these signs.

While some risk factors like age and family history can't be changed, others are within your control. These small steps can make a big difference:

• Stay active: Regular exercise helps keep your heart and blood vessels healthy.
• Eat well: A diet rich in fruits, vegetables, and whole grains reduces the risk of stroke.
• Manage your numbers: Keep your blood pressure, cholesterol, and blood sugar levels in check.
• Quit smoking: Smoking damages blood vessels and significantly increases stroke risk.
• Drink responsibly: Limiting alcohol consumption helps maintain healthy blood pressure and prevents plaque build-up.

Understanding stroke is the first step in protecting yourself and your loved ones. By learning the causes, symptoms and preventive measures, you can take control of your health and reduce the risk of stroke.

If yours or someone else's life is in danger, dial 000 immediately.

The Stroke Foundation offers comprehensive guides on prevention, treatment and recovery. You can also call StrokeLine on 1800 787 653 for advice and to be connected to services for survivors, family and carers.