Science Inventory

The combination of environmental quality with increasingly rural residence and associations with adverse birth outcomes


Messer, L., C. Gray, S. Grabich, J. Jagai, Y. Jian, K. Rappazzo, AND D. Lobdell. The combination of environmental quality with increasingly rural residence and associations with adverse birth outcomes. Epidemiology Congress of the Americas 2016, Miami, FL, June 21 - 24, 2016.


The purpose of this study was to explore overall environmental quality in relation to birth outcomes in the U.S., accounting for rural/urban differences and race/ethnicity. This study utilized the EPA created Environmental Quality Index.


Environmental quality differs across levels of urbanicity, and both urban and rural residence having been previously associated with better health. To explore these relationships, we constructed an environmental quality index (EQI) with data representing five domains (air, water, land, built, sociodemographic) for each United States (U.S.) county. Nine categories of rural-urban continuum codes ranging from (RUCC1 (most urban) to RUCC9 (most rural)) were used to group 3141 counties for analyses. Using six years of geocoded birth records (2000-2005) from the National Center for Health Statistics (n=24,347,911births), we estimated prevalence ratios (PR) and 95% confidence intervals (95% CI) from fixed slope, random intercept log binomial regression models, clustered at the county-level. White non-Hispanic (NH), black NH and Hispanic race-stratified birth outcomes (preterm birth (PTB); very PTB; low birth weight (LBW); very LBW; term LBW and PTB-LBW) were estimated with standard outcome definitions applied. Models were adjusted for maternal age, education, and marital status. Across counties, the linear combination of the EQI with increasingly rural residence was associated with decreased odds of all six birth outcomes for white NH women (e.g., RUCC9 PTB-LBW white NH PR = 0.92 (95% CI: 0.87, 0.90), compared with the most urban counties (RUCC1). This pattern was largely replicated among Hispanic women (e.g., RUCC9 PTB-LBW PR=0.90 (95%CI: 0.82, 0.98)). The pattern differed for black NH births, however, for which increasingly rural residence (RUCC9) was associated with increased PTB-LBW (PR=1.05; 95% CI: 0.99, 1.11). More consistency was seen for white NH and Hispanic births than for black NH births. The combination of environmental quality across levels of urbanicity was associated with perinatal health, with effects differing by race/ethnicity.Disclaimer: This abstract does not necessarily reflect EPA policy.

Record Details:

Product Published Date: 06/24/2016
Record Last Revised: 06/20/2016
OMB Category: Other
Record ID: 319576