Differential Ambient Air Pollution Exposure in a Chronic Obstructive Pulmonary Disease Cohort: The Role of Area-Level Socioeconomic Factors

Abstract

Abstract Background: Disparities in environmental exposures have been investigated in a multitude of epidemiologic studies. Many of these studies have demonstrated that minorities and poorer individuals were disproportionately exposed to elevated levels of air pollution and other environmental hazards. To date, differential air pollution exposures have not been assessed in a cohort of individuals with compromised respiratory health. We evaluated the distribution of air pollution exposures in such a cohort by area-level socioeconomic factors. Methods: Data from the National Emphysema Treatment Trial (NETT) (1998–2003), which included 1218 subjects ages 39–84, were linked with air pollution data from the U.S. Environmental Protection Agency Air Quality Systems database. The air pollution data included daily values of fine particulate matter (PM2.5) and ozone. ZIP code specific exposures were spatially interpolated with the use of log-normal kriged models. This methodology was employed in order to assign exp...