Exposure to Air Pollution May Increase Risk of Alzheimer’s Disease

Posted: Apr. 14, 2013

The study, led by Cure Alzheimer’s Research Consortium member Sam Gandy, M.D., Ph.D., of the Icahn School of Medicine at Mount Sinai, examined how elements in air pollution such as nickel nanoparticles affect the levels of certain peptides in the brain that are found to be at heightened levels in patients suffering from Alzheimer’s Disease.

“We don’t yet completely understand why the peptides accumulate, but we do know the genes responding to the peptides play an important role in developing Alzheimer’s,” said Gandy.

To test the correlation, mice were examined 24 hours after being exposed to air pollution where they showed a 72-129 percent increase in levels of the peptides.

“We were startled when three hours of air pollution exposure for the mice showed such a rapid and dramatic elevation,” said Gandy.

While the study links air pollution to Alzheimer’s, Gandy emphasized that more research is needed to better understand the role of genetics saying, “There is probably some interaction between genetic susceptibility to air pollution that mitigates the response to the exposure.”

Additionally, the study emphasized the need to better understand air pollution’s effects on humans in a natural setting.

“We suspect that humans will have an even more dramatic reaction to air pollution than mice because the human molecule is far stickier, making it highly prone to clumping and accumulation,” said Gandy. This could mean an even stronger link between air pollution and Alzheimer’s than is reflected in the study’s findings.

Interest in linking air pollution exposure to Alzheimer’s disease started when studies showed young people living in highly polluted cities to have Alzheimer's disease pathology, and because of existing evidence linking air pollution to insulin resistance and type 2 diabetes.

“We wanted to see if we could better explain why so many people were showing signs of Alzheimer’s at such a young age,” Gandy said. “The results of this study clearly show an urgent need to better understand this link.”

Read the published paper here.  Read a 4/9/13 publication from Annals of Internal Medicine linking air pollution to cognition here.