(HealthDay News) — Long-term exposure to ambient air pollution may be linked to subtle changes in the brain that could lead to cognitive impairment, a new study suggests. The report was published online April 23 in Stroke.
Elissa Wilker, Sc.D., an instructor in medicine at Harvard Medical School in Boston, and colleagues collected data on 943 adults who took part in the Framingham Offspring Study, a long-term study that included people from Framingham, Mass. All were free of dementia and had not had a stroke at the start of the study.
From 1995 to 2005, the researchers used magnetic resonance imaging to determine the effect of long-term exposure to air pollution on the brain. They found that a 2-µg/m³ increase in fine particulate matter was associated with a 0.3 percent smaller total cerebral brain volume and a 46 percent higher risk of covert brain infarcts.
“Our findings suggest that air pollution is associated with insidious effects on brain aging, even in relatively healthy older people,” Wilker told HealthDay. The toll of long-term exposure to this type of pollution is about equal to an extra year of brain aging. “The association with silent strokes is of concern, because these are associated with increased risk of serious strokes, walking problems, and depression,” Wilker said.