Short-term exposure to air pollution can raise stroke risk
The risk of stroke increases by as much as 30% within five days of being exposed to air pollution, according to new research.
Researchers looked at 110 observational studies from around the world that noted when strokes happened and the concentrations of common pollutants in the air within five days of people having a stroke. Results of the meta-analysis were published in the journal Neurology.
“Air pollution’s impact on human health extends beyond the lung and eyes. It also involves the brain and cardiovascular system,” researcher Ahmad Tubasi of the University of Jordan, who led the research, said on NBC News. “The meta-analysis included more than 18 million cases of ischemic stroke, the most common type of stroke, which is caused by a blood clot traveling to the brain,” NBC reported. “The researchers found that stroke risk was nearly 30% higher when people had been exposed to nitrogen dioxide up to five days prior. For carbon monoxide exposure, the risk was 26% higher; for sulfur dioxide, 15% higher; and for ozone exposure, 5% higher.”
In addition, short-term exposure to nitrogen dioxide was linked to a 33% higher risk of dying from stroke. For sulfur dioxide, it was 60% higher. Breathing in bits of particulate matter causes inflammation and irritation in the lungs. This causes your immune system to kick into gear, eventually affecting the cardiovascular system, said Michael Kleinman of the Air Pollution Health Effects Laboratory at the University of California, Irvine, who did not work on the research. “There is a direct link between what goes on in the lung and what goes on in the heart,” he said.