What Causes a Stroke?
A stroke occurs when blood flow to the brain is interrupted or reduced, preventing brain tissue from receiving necessary oxygen and nutrients. Understanding the causes of stroke is crucial for prevention and intervention. Here are the primary causes:
1. Ischemic Stroke
This type accounts for about 87% of all strokes and is caused by a blockage in an artery supplying blood to the brain. The blockage can result from:
- Blood Clots: These may form due to plaque buildup (atherosclerosis) in arteries.
- Embolism: Clots formed elsewhere in the body can travel to the brain, blocking blood flow.
2. Hemorrhagic Stroke
This occurs when a weakened blood vessel ruptures, leading to bleeding in or around the brain. Common causes include:
- Aneurysms: Bulges in blood vessels that can burst.
- Arteriovenous Malformations: Abnormal connections between arteries and veins that can rupture.
3. Risk Factors
Several lifestyle and health factors increase the risk of stroke:
- High Blood Pressure: The leading cause of stroke.
- Diabetes: Increases the risk of stroke by damaging blood vessels.
- Smoking: Damages blood vessels and promotes clot formation.
- High Cholesterol: Contributes to plaque buildup.
- Obesity: Associated with various risk factors.
Recognizing these causes and risk factors can significantly aid in stroke prevention.