Spending just five days in an area with air pollution could increase your risk of a stroke and double your risk of death from a stroke.
Researchers in Jordan reviewed more than 100 studies that included data from 18 million stroke patients. They found that patients exposed to pollutants like nitrogen dioxide, ozone, carbon monoxide, and sulfur dioxide had an increased risk of stroke and death by up to 60 percent.
And experts estimate that up to one-third of Americans live in areas where pollution is dangerously high.
These findings suggest that even short periods of time, like a long weekend trip with the family, in highly polluted cities could lead to disastrous health consequences.
Dr Ahmad Toubasi, lead study author and physician at the University of Jordan, said: ‘There is a strong and significant association between air pollution and the occurrence of stroke as well as death from stroke within five days of exposure.
‘This highlights the importance of global efforts to create policies that reduce air pollution. Doing so may reduce the number of strokes and their consequences.’
These pollutants can come from cars, power plants, wildfires, and refineries.
Researchers in Jordan reviewed more than 100 studies of 18 million strokes. They found pollutants like nitrogen dioxide, ozone, carbon monoxide, and sulfur dioxide increased the risk of dying from a stroke by up to 60 percent
Dr Tubasi and his team looked at data from 110 observational studies conducted in Asia, Europe, North America, and South America. The researchers also analyzed the presence of nitrogen dioxide, ozone, carbon monoxide, and sulfur dioxide in the air within five days of people suffering an ischemic stroke, the most common type caused by a blood clot traveling to the brain.
They also measured exposure to particulate matter, or microscopic particles from dirt, dust, and smoke. These range from less than one micron in diameter (PM1) to 10 times that size (PM10).
People exposed to higher concentrations of nitrogen dioxide were 28 percent more likely to have a stroke, while ozone was linked to a five percent increase. Carbon monoxide led to a 26 percent greater risk, while sulfur dioxide resulted in a 15 percent increase.
Additionally, people exposed to higher concentrations of PM1 were nine percent more likely to have a stroke, with PM2.5 increasing the risk by 15 percent, and PM10 increasing the risk by 14 percent.
The researchers also found higher levels of short-term air pollution exposure was linked to a greater risk of death from stroke. Nitrogen dioxide exposure was linked to a 33 percent increased risk of death from stroke, and sulfur dioxide was linked to a 60 percent increase. Those exposed to higher levels of PM2.5 and PM10 were nine percent and two percent more likely to die from stroke, respectively.
‘Previous research has established a connection between long-term exposure to air pollution and an increased risk of stroke,’ Dr Toubasi said.
‘However, the correlation between short-term exposure to air pollution and stroke had been less clear. For our study, instead of looking at weeks or months of exposure, we looked at just five days and found a link between short-term exposure to air pollution and an increased risk of stroke.’
Fine particles, or soot, are tiny particles in the air released by wildfires, wood-burning stoves, coal-fired power stations, diesel engines and other sources.
This pollution is made up of small microscopic particles in the air that can irritate the eyes, nose, and throat.
In the short term, it can cause itchiness, coughing, sneezing, and shortness of breath.
Over time, these chemicals can embed themselves in the lungs and bloodstream, disrupting bodily functions.
Further, they can damage the DNA of the lungs and other vital organs and increase a person’s risk of developing cancer.
Ozone pollutants, on the other hand, are also released by cars, power plants, refineries and power stations, but they have reacted with sun’s ultraviolet rays — causing ‘smog’ to emerge.
Inhaling them is equivalent to giving your lungs ‘sunburn,’ doctors say.
These reactions create toxic gas that can cause harm to the lungs after just days of exposure and be especially dangerous to people suffering from asthma or COPD.
The American Lung Association’s ‘State of the Air’ report also found roughly 103 million people lived in the 124 counties that earned an F grade for ozone smog, and 120 million Americans are in areas with ‘dangerously high’ levels of the pollutants.
The researchers did note that a study limitation was most data came from high-income countries, as there was limited data on lower-income areas.
The new study was published Wednesday in the journal Neurology.