Living in an environment heavily polluted with particulate matter significantly increases the risk of ischemic stroke. One potential cause may be changes in clotting factors that lead to the formation of blood clots in the brain.
Researchers from Beth Israel Deaconess Medical Center in the United States examined the relationship between air pollution and stroke in nine American cities, based on medical records of approximately 150,000 cases of ischemic stroke and 19,000 cases of hemorrhagic stroke from 1986 to 1999. This study is regarded as the largest of its kind to date, as previous research primarily focused on other cardiovascular diseases.
Results showed that increases in particulate matter in polluted air, ranging from the lowest to the highest levels, corresponded to a 1.3% increase in hospital admissions for ischemic stroke on the same day. In contrast, no correlation was found between air pollution and hospital admissions for hemorrhagic stroke.
According to the lead researcher Gregory A. Wellenius, there are three potential underlying causes, which may act independently or in combination to have an impact. First, strokes may result from a series of inflammatory responses triggered by air pollution. Second, when particulate matter enters the lungs, it can stimulate reactions that alter blood pressure or heart rhythm. Finally, changes in clotting factors may promote the formation of blood clots that travel to the brain and cause blockages.
Mỹ Linh
