The cardiovascular system delivers oxygen and nutrients to the body's tissues. It also removes waste from tissues via the circulation of blood. The heart acts as the pump for this system, pushing blood through vessels to the lungs and tissues. Diseases of the heart, such as heart attack, disrupt its pumping function. A stroke, sometimes called a brain attack, occurs when soemthing blocks blood supply to part of the brain, or when a blood vessel in the brain bursts. In either case, parts of the brain become damaged or die. To work properly, your brain needs oxygen. Your arteries deliver oxygen-rich blood to all parts of your brain. If something happens to block the flow of blood, brain cells start to die within minutes, because they can't get any oxygen. This causes stroke. A stroke can cause lasting brain damagem, long-term disability, or even death.
Why is this important?
Heart disease and stroke currently claim more lives each year than cancer and chronic lower respiratory disease combined. According to a report from the American Heart Association, each year, about 805,000 Americans have a heart attack. Of these 650,000 are a first heart attack and 200,000 happen in people who have already had a heart attack. About 1 in 5 heart attacks are silent, the damage is done, but the person is not aware of it.
What is known?
Environmental factors can increase the risk of heart attack and stroke. According to the American Heart Association, studies have shown an increased risk of heart attack and stroke events in relation to exposure to air pollution.
Many factors contribute to heart disease, including your genes. But growing medical evidence links air pollution and heart disease. Whether you live in a city where smog forecasts are routine or in a less populated place, tiny pollution particles in the air can lead to big problems for your heart. Pollution can come from traffic, factories, power generation, wildfires or even cooking with a wood stove. One of the most common indoor sources is smoking, a danger both to the person lighting up and to those nearby.
Short-term exposure to air pollution can increase the risk of heart attack, stroke, arrhythmias and heart failure in susceptible people, such as the elderly or those with preexisting medical conditions. The risk of death is greater from long-term exposure. Current science suggests air pollution aids the development and progression of atherosclerosis, plaque that builds up in the artery walls and causes heart disease. Pollution also may play a role in high blood pressure and diabetes.
Who is at risk?
Risk factors for heart attack include:
- Family history
- High blood pressure
- Tobacco use
- High cholesterol
- Physical inactivity
- Diabetes
- Obesity
- Exposures to environmental contaminants
Risk factors for stroke include:
- Previous stroke or transient ischemic attack (TIA), also known as a "mini-stroke"
- High blood pressure
- High Cholesterol
- Heart disease and other heart conditions such as heart valve defects, irregular heartbeat such as atrial fibrillation
- Sickle Cell Disease
- Diabetes
- Obesity
- Physical inactivity
- Exposures to environmental contaminants
You can reduce the risk of having a heart attack or stroke by losing weight, not smoking, exercising regularly, and having a healthy diet. People who are at risk for a heart attack should avoid strenuous activity in areas with elevated particulate air pollution, such as not jogging along a busy street.
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