Causes

The different forms of stroke have different specific causes.

1. Causes of ischemic stroke

Ischemic stroke is the most common form, accounting for around 85 percent of strokes. This type of stroke is caused by blockages or narrowing of the arteries that provide blood to the brain, resulting in ischemia – severely reduced blood flow that damages brain cells.

These blockages are often caused by blood clots, which can form either in the arteries within the brain, or in other blood vessels in the body before being swept through the bloodstream and into narrower arteries within the brain. Fatty deposits within the arteries called plaque can cause clots that result in ischemia.

2. Causes of hemorrhagic stroke

Hemorrhagic strokes are caused by arteries in the brain either leaking blood or bursting open. The leaked blood puts pressure on brain cells and damages them. It also reduces the blood supply reaching the brain tissue after the hemorrhage point. Blood vessels can burst and spill blood within the brain or near the surface of the brain, sending blood into the space between the brain and the skull.

The ruptures can be caused by conditions such as hypertension, trauma, blood-thinning medications, and aneurysms (weaknesses in blood vessel walls).

Intracerebral hemorrhage is the most common type of hemorrhagic stroke and occurs when brain tissue is flooded with blood after an artery in the brain bursts. Subarachnoid hemorrhage is the second type of hemorrhagic stroke and is less common. In this type of stroke, bleeding occurs in an artery in the subarachnoid space – the area between the brain and the thin tissues that cover it.

The best way to prevent a stroke is to address the underlying causes. This is best done by living healthfully, which means:

1. Eating a healthy diet.

2. Maintaining a healthy weight.

3. Exercise regularly.

4. Don’t smoke.

5. Avoiding alcohol or drink moderately.