Effects of Traffic-Related Air Pollution on Cognitive Function, Dementia Risk, and MRI Brain Findings in the Cardiovascular Health StudyEPA Grant Number: FP917124
Title: Effects of Traffic-Related Air Pollution on Cognitive Function, Dementia Risk, and MRI Brain Findings in the Cardiovascular Health Study
Investigators: Semmens, Erin O’Brien
Institution: University of Washington
EPA Project Officer: Michaud, Jayne
Project Period: September 1, 2010 through August 31, 2013
Project Amount: $111,000
RFA: STAR Graduate Fellowships (2010) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Fellowship - Human Health: Public Health Sciences
Long-term exposure to air pollution, particularly traffic-related air pollution, is associated with cardiovascular (CV) morbidity and mortality; however, less is known about the impact of these exposures on neurodegenerative disorders. Evidence indicates that systemic inflammation, a response to which the brain is particularly vulnerable, may mediate CV effects, suggesting that neurodegenerative disorders may also be subject to this environmental injury. The proposed research will investigate associations between air pollution exposure and cognitive decline, risk of dementia, and MRI-detected brain abnormalities in the Cardiovascular Health Study (CHS), a large, National Heart, Lung and Blood Institute–funded longitudinal study of coronary heart disease and stroke in older adults.
Links between air pollution and cardiovascular disease (CVD) have been the focus of intense research. Although CVD and Alzheimer’s disease (AD) share similar risk factors, and environmental exposures likely play a role in AD, potential links between air pollution and AD remain largely unexplored. This project evaluates the relationship between traffic-related air pollution exposure and cognitive decline, dementia, and MRI-detected brain abnormalities in a large population of older adults.
This study will include men and women aged 65 years and older, living in four communities in the United States, who were recruited into the CHS between 1989 and 1993 and who participated in annual clinical exams through 1999. Air pollution exposure will be estimated by calculating proximity of residences to major roadways using a geographic information system. In addition, the study will utilize already-collected monthly individual estimates of exposure to NO2, CO, O3, SO2, and PM10. Outcomes will include cognitive performance, prevalent and incident dementia (both AD and vascular dementia), presence of MRI-detected brain abnormalities including brain infarcts and white matter disease, and changes in these measures over time. This project takes advantage of the unique population-based phenotypic resource of repeated brain MRIs and cognitive assessments in CHS to examine the effects of air pollution on the brain.
This project will characterize more broadly the health effects of air pollution exposure. Although consistent links between air pollution and cardiovascular disease have been observed, the potential contribution of air pollution exposure to neurodegeneration is a novel research direction. This research is one of the first large studies with extensive information on potentially confounding factors, such as socioeconomic status, to investigate the effects of air pollution on cognitive performance, risk of dementia, and subclinical brain abnormalities, which carry elevated risk of cognitive decline and stroke. This project has the opportunity to bring together new collaborations of data sources and expertise for a complex and resource-efficient study.
Potential to Further Environmental/Human Health Protection:
This project will provide novel and important information on the relationship between air pollution and the brain. Findings will provide a broader understanding of the health risks associated with air pollution exposure to guide policy decisions and future efforts to improve public health.