Air pollution is not just a threat to your lungs. When the Air Quality Index (AQI) rises, harmful pollutants in the air can also affect your blood vessels, including those supplying blood to the brain. Long-term exposure to polluted air is associated with an increased risk of stroke.
7 Ways Rising AQI Can Affect Brain Health
1. Air Pollution Can Damage Blood Vessels
Fine particles called PM2.5 can enter deep into the lungs and trigger inflammation and other harmful responses in the body. Over time, this may damage the inner lining of blood vessels, including arteries supplying the brain.
2. It Can Increase Stroke Risk
Research links long-term exposure to air pollution with a higher risk of stroke. Pollution may contribute to blood vessel damage, inflammation and other changes that increase the likelihood of a stroke.
3. It May Raise Blood Pressure
Exposure to polluted air can temporarily increase blood pressure in some people. High blood pressure is one of the leading risk factors for stroke because it puts extra strain on blood vessels.
4. It Can Promote Blood Clot Formation
Air pollution may affect the body’s clotting mechanisms and make blood vessels more vulnerable to blockages. If a clot blocks blood flow to part of the brain, an ischemic stroke can occur.
5. It Can Trigger Inflammation and Oxidative Stress
Tiny airborne particles can trigger inflammation and oxidative stress, which may contribute to damage in blood vessels throughout the body, including the brain.
6. People With Existing Health Conditions May Face Greater Risk
Older adults and people with high blood pressure, diabetes, heart disease or a history of stroke may be particularly vulnerable to the effects of air pollution.
7. Simple Steps Can Help Reduce Exposure
- Check the daily AQI before going outdoors.
- Reduce strenuous outdoor exercise when pollution levels are high.
- Keep windows closed during severe pollution episodes when outdoor air is worse.
- Use a properly sized HEPA air purifier indoors if possible.
- Wear a well-fitting N95 mask when exposure to fine particles cannot be avoided.
When Should You Seek Emergency Help?
Recognise the warning signs of stroke using FAST:
- F – Face: One side of the face droops.
- A – Arms: One arm suddenly becomes weak.
- S – Speech: Speech becomes slurred or difficult.
- T – Time: Call emergency services immediately.
Sudden vision problems, loss of balance or a severe unexplained headache can also be warning signs. Do not wait for symptoms to disappear.
Important: Rising AQI does not automatically mean your brain arteries are blocked. However, air pollution is a recognised cardiovascular and cerebrovascular risk factor, and reducing exposure can help protect your health.
