Stroke
What is a stroke?
A stroke, also known as a brain attack, is a critical medical emergency that occurs when blood flow to a part of the brain is interrupted or reduced. This disruption is often caused by a blocked artery (ischemic stroke) or bleeding in the brain (haemorrhagic stroke). Without a continuous supply of oxygen and nutrients, brain cells in the affected area die within minutes, leading to a loss of brain function.
The brain requires a constant flow of oxygen-rich blood to operate effectively. When this flow is compromised, even for a short duration, it can result in significant damage. As brain cells die, the abilities controlled by that part of the brain—such as movement, speech, memory, and coordination—may become impaired or lost entirely.
Since stroke affects the brain, its impact varies depending on the area affected and the extent of damage. Prompt medical attention is crucial to minimize brain damage and improve recovery outcomes.
What are the different types of strokes?
The main types of strokes include:
- The most common type, accounting for about 87% of all strokes.
- It is caused by a blockage in an artery supplying blood to the brain, often due to a blood clot or buildup of fatty deposits (atherosclerosis).
1. Ischemic Stroke
- It occurs when a blood vessel in the brain bursts, leading to bleeding in or around the brain.
- It is less common but more severe than ischemic strokes.
2. Haemorrhagic Stroke
- A temporary blockage of blood flow to the brain, often lasting a few minutes to hours.
- Symptoms resolve without permanent damage but serve as a warning sign of a future stroke.
3. Transient Ischemic Attack (TIA) (Mini-Stroke)
Prompt medical attention is crucial for all types of strokes to reduce brain damage and improve recovery outcomes.
What causes stroke?
The causes of stroke vary depending on the type of stroke but generally involve issues that disrupt blood flow to the brain. Here are the primary causes:
Causes of Ischemic Stroke (Most Common Type)
It occurs when a blood vessel supplying the brain is blocked or narrowed.
- Blood Clots (Thrombosis): Clots can form in the brain's arteries due to atherosclerosis (plaque buildup).
- Embolism: A clot or debris traveling from another body part, often from the heart (as in atrial fibrillation), blocks a brain artery.
- Atherosclerosis: Hardening and narrowing of the arteries due to cholesterol plaque buildup.
- Small Vessel Disease: Blockages in smaller blood vessels within the brain.
Causes of Haemorrhagic Stroke (Bleeding in the Brain)
It occurs when a blood vessel ruptures, leading to bleeding in or around the brain.
- Uncontrolled High Blood Pressure (Hypertension): Weakens blood vessels, making them prone to rupture.
- Aneurysm: A weakened, bulging area in a blood vessel that can burst.
- Arteriovenous Malformation (AVM): Abnormal tangling of blood vessels that can rupture.
- Head Injury or Trauma: Severe impact on the head can cause brain bleeding.
- Blood Thinners: Medications like anticoagulants can increase bleeding risk.
Causes of Transient Ischemic Attack (TIA) (Mini-Stroke)
Temporary blockage of blood flow, often due to:
- Small blood clots or plaque debris temporarily block an artery.
- Narrowed arteries due to atherosclerosis.
What are the symptoms of Stroke?
If you suspect a stroke, act quickly and note when symptoms first appear, as specific treatments are most effective when administered shortly after the stroke begins.
Common Stroke Symptoms:
- Speech Difficulties: Trouble speaking clearly, slurred speech, confusion, or difficulty understanding others.
- Numbness or Weakness: Sudden weakness, numbness, or paralysis in the face, arm, or leg, often affecting one side of the body. If the person raises both arms and drifts downward, it may indicate a stroke. A drooping smile on one side is also a key sign.
- Vision Problems: Sudden blurred, blackened, or double vision in one or both eyes.
- Severe Headache: A sudden, intense headache that may be accompanied by dizziness, vomiting, or loss of consciousness.
- Balance and Coordination Issues: Trouble walking, stumbling, dizziness, or a loss of coordination.
Additional Stroke Warning Signs:
- One-sided muscle weakness or paralysis.
- Difficulty speaking (aphasia) or slurred speech (dysarthria).
- Loss of muscle control in the face.
- Sudden sensory loss (vision, hearing, smell, taste, touch).
- Blurred or double vision.
- Dizziness, vertigo, or nausea.
- Neck stiffness.
- Emotional changes and confusion.
- Seizures.
- Memory loss or amnesia.
- Fainting or passing out.
- Coma (in severe cases).
Recognizing these signs early can help prevent severe complications. Seek emergency medical care immediately if you notice any of these symptoms.
What are the risk factors of stroke?
A stroke can affect anyone, regardless of age. However, certain risk factors can increase the likelihood of experiencing a stroke. While some risk factors are unchangeable, medical intervention can modify or manage others.
Modifiable Risk Factors for Stroke:
- High Blood Pressure: A reading of 140/90 or higher can damage the arteries that supply blood to the brain, significantly increasing the risk of stroke.
- Heart Disease: This condition is a significant risk factor for stroke and contributes to the high mortality rate among stroke survivors. Many of the risk factors for heart disease overlap with those of stroke.
- Diabetes: People with diabetes face a higher risk of stroke compared to those without the condition.
- Smoking: Smoking nearly doubles the risk of ischemic stroke.
- Oral Contraceptives: Birth control pills may elevate stroke risk, especially for women who smoke or have other risk factors.
- History of TIAs: Transient Ischemic Attacks (mini-strokes) increase stroke risk by nearly tenfold for those who have experienced them.
- High Red Blood Cell Count: An elevated red blood cell count thickens the blood, increasing the likelihood of clot formation, which can trigger a stroke.
- High Cholesterol: Elevated cholesterol levels can lead to plaque buildup in arteries, contributing to atherosclerosis and reducing blood flow to the brain.
- Physical Inactivity: Lack of exercise can contribute to many health conditions that raise stroke risk.
- Obesity: Excess weight increases the risk of stroke due to its effect on various other health factors.
- Excessive Alcohol Use: Drinking more than two alcoholic beverages a day can raise blood pressure and contribute to stroke risk. Binge drinking significantly increases this risk.
- Illicit Drug Use: Intravenous drug abuse, particularly cocaine, dramatically increases stroke risk due to the formation of blood clots.
- Abnormal Heart Rhythm: Irregular heartbeats (atrial fibrillation) increase the likelihood of stroke and are treatable with proper medical care.
- Heart Valve Disease: Structural issues with the heart, such as damaged valves, can lead to long-term heart problems, raising stroke risk.
Non-Modifiable Risk Factors for Stroke:
- Age: Stroke risk increases significantly, especially after 55, doubling the risk every decade.
- Race: African Americans have a much higher risk of death and disability from stroke compared to white populations due in part to higher rates of high blood pressure.
- Gender: While strokes are more common in men, women have a higher likelihood of dying from stroke.
- Previous Stroke: If you've had one stroke, you're at a higher risk for another.
- Family History: A family history of stroke increases the likelihood of having one.
When to see a doctor
Don’t hesitate—time is crucial. The longer a stroke goes untreated, the higher the risk of severe brain damage and long-term disability. If you're with someone showing symptoms of a stroke, stay calm and keep an eye on them while waiting for emergency help.
- B - Balance: Watch for a sudden loss of balance or coordination.
- E - Eyes: Look for sudden vision loss in one or both eyes or double vision.
- F - Face: Ask the person to smile. Check for a drooping face, indicating muscle weakness or paralysis.
- A -Arms: Have the person raise both arms. If one arm sags or drops, it could signal muscle weakness.
- S - Speech: Slurred speech or difficulty speaking may occur in someone having a stroke.
- T - Time: Act quickly—note when the symptoms started and tell the healthcare provider so they can determine the most effective treatment.
To help recognize stroke symptoms quickly, use the "BE FAST" method:
The sooner a stroke is treated, the better the chance for a full recovery without lasting disability. Call us as soon as stroke symptoms are detected for immediate help.