Smog over downtown Los Angeles, which is among the top five worst U.S. cities for air pollution. Steven Buss/Flickr
Older women who live in places with high air pollution levels are 92 percent more likely to develop dementia, including Alzheimer’s, according to a new study by scientists at the University of Southern California. The risk is heightened even more in women with the APOE4 gene, a genetic variation associated with an increased chance of developing Alzheimer’s. It is the latest in a growing number of studies linking air pollution with dementia.
The 11-year study looked at health data for 3,647 U.S. women aged 65 to 79 living in 48 states, as well as laboratory experiments on the impact of particulate matter on female mice brains. The scientists found that in mice exposed to air pollution, particulate matter accumulated and damaged neurons in the hippocampus, the part of the brain responsible for memory. They also found that older women who live in areas where pollution levels exceed U.S. EPA standards — most often from power plants and car exhaust — are 81 percent more at risk to experience cognitive decline. The new study examined only women and female mice. Researchers said future studies will include both sexes.
“Microscopic particles generated by fossil fuels get into our body directly through the nose into the brain,” USC scientist Caleb Finch, an expert on aging and co-author of the study, said in a statement. “Cells in the brain treat these particles as invaders and react with inflammatory responses, which over the course of time, appear to exacerbate and promote Alzheimer’s disease.”
