Particulate Air Pollutants, Brain Structure, and Neurocognitive Disorders in Older Women

Research Report 193 describes a study led by Jiu-Chiuan Chen of the University of Southern California (USC), a recipient of HEI’s Walter A. Rosenblith New Investigator Award, to examine possible associations between long-term exposure to ambient particulate matter (PM) and changes in the brains of older women in the United States. The study focused on brain volumes and on neurocognitive outcomes, specifically mild cognitive impairment and dementia. Dr. Chen used neuroimaging and cognitive outcome data from women enrolled in the Women’s Health Initiative Memory Study. To estimate the women’s exposure, Dr. Chen and his collaborators at USC, the University of North Carolina–Chapel Hill, and Wake Forest University used two PM exposure metrics: ambient PM_2.5 at the residential address (using a nationwide spatiotemporal model based on central monitoring data) and on-road diesel PM at the census-tract level (based on data from the National-Scale Air Toxics Assessment).