UCSF

As our population ages, mounting interest lies in alleviating the illnesses of our older populations. Alzheimer’s Disease and related dementias affect 5.8 million Americans as of 2019, and this figure is set to grow to 7.1 million by 2050. This translates to current annual healthcare costs in excess of $1 trillion. There are 12 identified modifiable risk factors for dementia that could prevent up to 40% of dementia incidence, including air pollution, which was added in 2020. This objective of this dissertation was to examine the role of air pollution and socioeconomic position on cognition over six years in the National Health and Aging Trends Study (NHATS). As air pollution is socially patterned, there is a need to evaluate its interaction with social factors on cognition and cognitive decline. Chapter 1 of this dissertation compares racial and socioeconomic measures, from 2000 to 2015, across the conterminous US in exposure to outdoor nitrogen dioxide (NO2) and fine particulate matter (PM2.5). Chapter 2 builds upon Chapter 1 by using the individual and area-level metrics at the census tract level to examine their interaction with air pollution exposure on cognition in NHATS. Finally, the temporal pattern of air pollution exposure may be relevant to risk of cognitive decline in older adulthood. In Chapter 3, we characterized 10-year trajectories of PM2.5 and NO2 exposure at the census-tract level using sequence analysis and cluster analysis, and evaluated their association with cognition among a cohort of older adults.