Neighborhood Environment and Asthma Exacerbation in Washington, DC

Approximately one in eight people in the United States have been diagnosed with asthma. Asthma is associated with significant medical expenditure and has been implicated as a leading reason for chronic school absences. Environmental risk factors such as access to green space and exposure to poor air quality are patterned such that some vulnerable populations may be at higher risk. Using data from DC Health, the Washington, DC, department of public health, this study investigated associations between neighborhood social, built, and natural environments and rates of asthma-related healthcare encounters by ZIP code between 2014 and 2017. We found that significant differences in rates exist between ZIP codes and for different subpopulations. Black boys had the highest overall rate, with 58.49 visits per 1,000 population, ranging by ZIP code from 0 to 88.56 visits. We found that the ZIP code Social Vulnerability Index was consistently associated with rates of healthcare encounters, but not access to green/open space or exposure to high traffic. However, we discuss how the ZIP code level may not be an appropriate level at which to investigate such built/natural environment features because of the proportion of variability that is found within rather than between ZIP codes. We end with a short discussion of ways that nurses, in particular school nurses, could help to address neighborhood environmental risk factors.