Air pollution may shrink brain
Breathing in polluted air over long periods of time may cause changes to a brain’s makeup and even lead to some level of cognitive impairment, according to a new study published in the journal Stroke.
A team from the Beth Israel Deaconess Medical Center in Boston tested 943 healthy adults living in New England region. All were 60 or older. By using MRI brain scans, the researchers focused on the effect of fine-particle pollution, caused by car exhaust and other factors. They discovered that if an area has a fine-particle pollution range of just 2 micrograms per cubic meter - which is common in most cities - it’s enough to cause a decrease in brain volume by 0.32 percent. That may not seem like much, but according to the researchers, that much brain volume loss is equivalent to one year of brain aging.
The scientists found that people in the study who lived in areas with higher levels of pollution did tend to have smaller brain volumes and also were at higher risk of "silent strokes." These are strokes that dont' cause symptoms, but can be seen on brain scans and have been known to contribute to a decrease in cognitive function.
Specifically, the research suggested that higher levels of pollution could raise a person's risk of silent strokes by as much as 46 percent.
This is the first study to find a connection between brain composition, air pollution and silent strokes. But the researchers noted that because the analysis was conducted at only one point in time, they cannot a suggest a clear cause and effect relationship. They said they hope to do more research on what about air pollution can alter brain structure.