A stroke happens when blood flow to part of the brain is interrupted or reduced, preventing brain tissue from getting the oxygen and nutrients it needs.
Within minutes, brain cells begin to die. Because of this, strokes are a medical emergency that require immediate attention.
However, many strokes can be prevented through screening and early management of risk factors.
What Is a Stroke?
A stroke occurs when something blocks or reduces blood flow to the brain.
The brain depends on a constant supply of oxygen-rich blood. When this flow is disrupted, brain cells begin to die, which can lead to lasting damage, disability, or death if not treated quickly.
There are two main types of stroke:
- Ischemic stroke: Caused by a blockage, often a blood clot or a buildup of fatty deposits (plaque) that narrows arteries supplying the brain. This type accounts for about 85% of strokes.
- Hemorrhagic stroke: Occurs when a weakened blood vessel ruptures and bleeds into the brain. The leaked blood increases pressure on brain tissue and damages cells.
- Transient ischemic attack (TIA): Often called a “mini-stroke,” a TIA causes temporary symptoms similar to a stroke but does not cause permanent damage. It is a serious warning sign that a major stroke could occur in the future.
What Causes a Stroke?
The most common causes of stroke involve damage to blood vessels or interruptions in blood flow. Over time, conditions that strain or block arteries can greatly increase the risk.
Major Risk Factors
- High blood pressure: The single most significant cause of stroke.
- Atherosclerosis: Plaque buildup in arteries, often related to high cholesterol.
- Atrial fibrillation (AFib): An irregular heartbeat that can cause clots to form in the heart and travel to the brain.
- Smoking: Narrows blood vessels and increases clot formation.
- Diabetes: Damages blood vessels and increases atherosclerosis risk.
- Obesity and inactivity: Contribute to high blood pressure, diabetes, and poor circulation.
- Excessive alcohol use: Can raise blood pressure and cause irregular heart rhythms.
- Family history: Genetic factors can increase risk, especially if combined with lifestyle risks.
How to Get Tested for Stroke Risk
Strokes often occur without warning, but several screenings can detect the conditions that lead to them.
Testing can identify narrowing arteries, blood clots, or irregular heart rhythms before they cause harm.
Common Stroke Screening Tests
- Carotid artery ultrasound: Uses sound waves to check for plaque buildup or blockages in the neck arteries that supply blood to the brain.
- Blood pressure check: Identifies hypertension, the leading cause of stroke.
- Cholesterol test: Measures levels of LDL (“bad”) cholesterol, which contributes to plaque buildup.
- Atrial fibrillation screening: Detects irregular heart rhythms through ECG (electrocardiogram) testing.
- CT or MRI scans (if indicated): Provide detailed images of the brain and blood vessels to identify signs of previous silent strokes or vascular issues.
- Blood sugar test: Evaluates diabetes and metabolic health, both key stroke risk factors.
Recognizing the Warning Signs of a Stroke
Even with prevention, everyone should know how to recognize the signs of a stroke. Quick response can save lives and reduce long-term damage.
Use the F.A.S.T. Method:
- F – Face drooping: One side of the face may droop or feel numb.
- A – Arm weakness: One arm may drift downward when both arms are raised.
- S – Speech difficulty: Speech may sound slurred or strange.
- T – Time to call 911: Every minute counts. Get emergency help immediately.
Other symptoms may include sudden confusion, loss of balance, blurred vision, or a severe headache with no known cause.
Protecting Your Brain Health
Strokes can change a life in moments, but prevention begins long before symptoms appear. Regular screenings, healthy habits, and awareness of warning signs can make all the difference.