Overview
A stroke occurs when blood flow to part of the brain is suddenly interrupted, either by a blocked artery (ischaemic stroke) or a burst blood vessel (haemorrhagic stroke), depriving brain cells of oxygen and causing them to begin dying within minutes.
Disease Summary
- Category
- Non-Communicable Disease
- Cause
- Interruption of blood flow to the brain, either from a blocked artery (ischaemic stroke) or a burst blood vessel (haemorrhagic stroke)
- Transmission
- Not applicable; stroke is a non-communicable cardiovascular condition and cannot be spread between people
- Body System
- Nervous System
- Preventable
- Yes
- Curable
- No
Symptoms
Common Symptoms
Stroke symptoms appear suddenly. Any of the following signs is itself a medical emergency requiring an immediate call for help.
Face Drooping
One side of the face may droop or feel numb, often noticed as an uneven smile.
Arm Weakness
One arm may feel weak or numb and drift downward when raised.
Slurred Speech
Speech may become slurred, strange, or difficult to understand.
Sudden Confusion
Sudden trouble understanding others or confusion about surroundings.
Danger Signs
Call emergency services immediately if any of the following occur.
Loss of Consciousness
Passing out or severely reduced alertness is a medical emergency.
Sudden Severe Headache
A sudden, severe headache with no known cause may indicate a haemorrhagic stroke.
Seizure
A seizure occurring alongside other stroke symptoms requires emergency care.
Sudden Vision Loss
Sudden trouble seeing in one or both eyes needs urgent evaluation.
Diagnosis
Clinical Assessment (FAST Test)
Emergency responders and clinicians quickly assess facial drooping, arm weakness, and speech difficulty using the FAST test.
Imaging
CT or MRI scans of the brain determine whether a stroke has occurred and whether it is ischaemic or haemorrhagic.
Neurological Examination
A detailed examination assesses the extent of brain function affected by the stroke.
Laboratory Tests
CT Scan of the Brain
Quickly distinguishes between an ischaemic stroke and a haemorrhagic stroke, guiding emergency treatment decisions.
MRI of the Brain
Provides more detailed images of brain tissue and can detect smaller strokes.
Blood Glucose Test
Checks for low or high blood sugar, which can cause symptoms that mimic a stroke.
Complete Blood Count and Clotting Tests
Assesses for bleeding or clotting problems that may affect treatment options.
Treatment
Clot-dissolving Medication (Thrombolysis)
Medication that dissolves blood clots can restore blood flow if given quickly after an ischaemic stroke.
Emergency Clot Removal or Bleeding Control
Procedures to physically remove a clot or control bleeding may be used depending on the type and severity of stroke.
Prevention
Control blood pressure
Managing high blood pressure is one of the most effective ways to reduce stroke risk.
Avoid tobacco use
Not smoking significantly lowers the risk of stroke.
Manage diabetes and cholesterol
Keeping blood sugar and cholesterol levels within target ranges reduces the risk of blood vessel damage.
Maintain a healthy lifestyle
Regular physical activity, a balanced diet, and limiting alcohol all contribute to lower stroke risk.
Risk Factors
High Risk
These factors substantially increase the likelihood of having a stroke.
- High blood pressure
- Atrial fibrillation (irregular heartbeat)
- Previous stroke or transient ischaemic attack (TIA)
Increased Risk
These factors are associated with a moderately higher risk of stroke.
- Diabetes
- High cholesterol
- Smoking
Additional Contributing Factors
Other factors linked with an increased likelihood of stroke.
- Older age
- Family history of stroke
- Physical inactivity and unhealthy diet
Complications
Paralysis or Weakness
Stroke can cause lasting weakness or paralysis, often on one side of the body.
Speech and Language Difficulties
Damage to areas of the brain controlling language can cause lasting difficulty speaking or understanding speech.
Cognitive and Emotional Changes
Stroke can affect memory, thinking, and mood, sometimes leading to depression.
When to Seek Medical Care
Any Sudden Stroke Symptom
Sudden facial drooping, arm weakness, or slurred speech should prompt an immediate call for emergency medical help.
Sudden Severe Headache
A sudden, severe headache with no known cause needs emergency evaluation.
Symptoms That Resolve on Their Own
Even if symptoms go away quickly, they may indicate a transient ischaemic attack (TIA) and still require prompt medical attention.
Difficulty Breathing or Swallowing
Can occur after a stroke and needs urgent assessment.
Prognosis
Best with Rapid Treatment
Outcomes are significantly better when treatment begins within the first few hours after symptoms start.
Variable Long-term Recovery
Recovery varies widely depending on stroke severity, location, and how quickly treatment was received.
Improvement with Rehabilitation
Many people regain function over time with physical, speech, and occupational therapy.
Differential Diagnosis
Hypoglycaemia (Low Blood Sugar)
Can cause confusion, weakness, and altered consciousness that may resemble stroke symptoms.
Migraine with Aura
Can cause temporary visual disturbances, numbness, or speech difficulty similar to stroke.
Seizure (Postictal State)
Weakness or confusion following a seizure can resemble stroke symptoms.
Bell's Palsy
Causes facial weakness or drooping but, unlike stroke, does not typically involve arm weakness or speech difficulty.
References
Centers for Disease Control and Prevention (CDC)
CDC guidance on recognizing stroke signs and symptoms using the FAST and BE FAST tests.
Centers for Disease Control and Prevention (CDC)
CDC guidance on stroke, transient ischaemic attacks, and emergency care.
World Health Organization (WHO)
WHO fact sheet on cardiovascular diseases, including stroke risk factors and prevention.
Frequently Asked Questions
Can a stroke be cured?
There is no cure, but prompt emergency treatment can limit brain damage, and many people regain significant function through rehabilitation.
What should I do if I think someone is having a stroke?
Call emergency services immediately, note the time symptoms started, and do not drive the person to the hospital yourself.
What is a transient ischaemic attack (TIA)?
A TIA, sometimes called a mini-stroke, causes stroke-like symptoms that resolve on their own but still signal a serious risk of a future major stroke and require prompt medical attention.
Can stroke be prevented?
Many strokes can be prevented by controlling blood pressure, avoiding tobacco use, managing diabetes and cholesterol, and maintaining a healthy lifestyle.