Social inequities in neighborhood health amenities over time in the Wasatch Front Region of Utah: Historical inequities, population selection, or differential investment?

Socially disadvantaged groups generally are more likely to reside in areas with less desirable conditions. We examined longitudinal relationships between neighborhood resident characteristics and amenities from 1990 to 2010 in a four-county urban area of Utah, U.S. Four temporal patterns of social inequities are described using mixed-effects models: historical inequities in amenities; differential selection into amenity-rich tracts; differential investment in amenities; and simultaneous twenty-year change. Results indicate historical differences by nSES, with lower status tracts having fewer green/natural amenities and higher air pollution in 1990 but also greater walkability and more food stores. Differences widened over time as nSES disproportionately increased in tracts with more green/natural amenities, less air pollution, and lower walkability in 1990, consistent with differential selection. Tract percentage non-Hispanic White did not predict historical differences, but tracts that were less walkable and had fewer healthy food stores per capita in 1990 experienced larger subsequent increases in racial/ethnic diversity. Tracts with higher percentage non-Hispanic White in 1990 had larger decreases in air pollution but also declining green/natural amenities relative to more diverse tracts. This study shows how social inequities in neighborhood amenities change over time, providing strong evidence of historical socioeconomic differences that increased due to differential selection.