The team conducted a meta-analysis, combining data from 110 previous studies with data from 18 million strokes, and analyzed pollutants such as nitrogen dioxide, ozone, carbon monoxide and sulfur dioxide.
Exposure to short-term air pollution can be linked to a increased risk of suffering stroke, according to a study published in the journal Neurology.
The research coordinated by the University of Jordan in Amman considered short-term exposure that occurred in the five days before the stroke.
Previous studies have established a connection between long-term exposure to air pollution and an increased risk of stroke, but the correlation for short-term exposure has been less clear.
Therefore, this study, instead of analyzing weeks or months of exposure, focused only on five days and found “a relationship between short-term exposure to air pollution and an increased risk of stroke“, indicated Ahmad Toubasi, one of the signatories of the text and from the aforementioned university, quoted by Neurology.
110 studies
The team conducted a meta-analysis, which combined data from 110 previous studies with data from 18 million strokes, and analyzed pollutants such as nitrogen dioxide, ozone, carbon monoxide and sulfur dioxide. They also took into account the different sizes of polluting particles, including PM1 (less than a micron in diameter), PM2.5 and PM10.
PM2.5 includes particles from exhaust pipes, fuel burning by industries or forest fires, and PM10 includes dust from roads or construction sites.
People who were exposed to a higher concentration of various types of air pollution had a higher risk of suffering a stroke. Higher PM1 concentration was associated with a 9% increased risk of stroke; that of PM2.5 was 15% and that of PM10, 14%.
Higher concentrations of nitrogen dioxide were linked to a 28% increased risk of stroke; higher ozone levels were associated with a 5% increase; carbon monoxide 26% and sulfur dioxide 15%.
Higher risk of death
The same way, the highest levels of pollution atmospheric conditions were related to a higher risk of death from stroke.
Thus, the highest concentrations of nitrogen dioxide were associated with a 33% increased risk of death; those of sulfur dioxide, with an increase of 60%; those of PM2.5, with an increase of 9%; and those of PM10 of 2%.
“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 exposurewhich highlights the importance of global efforts to create policies that reduce air pollution,” said Toubasi.
A limitation of the meta-analysis was that most studies were conducted in high-income countries, while few data were available from low- and middle-income countries.