Health Disparities
Race/ethnicity-specific associations of the combined effects of extreme temperature exposures and neighborhood socioeconomic disadvantage on birth outcomes in Harris County, Texas Wei-Jen Chen* Wei-Jen Chen Elaine Symanski Allan C. Just Kristina W. Whitworth
Evidence suggests that exposure to high temperatures during pregnancy and living in disadvantaged neighborhoods increases risks of preterm birth (PTB) and low birth weight (LBW) among newborn infants. However, the impact of these combined exposures has not been examined.
A retrospective cohort study was conducted using 123,138 singleton live birth records in Harris County, Texas (11/2018–12/2020). Census tract-level daily maximum air temperatures, assessed using the “XGBoost-IDW Synthesis” model, were linked to mothers’ residence at delivery and averaged across their gestational period. Average temperatures were dichotomized at the 90th percentile (i.e., 29.35 ℃). Neighborhood disadvantage was assigned based on the census tract-level Area Deprivation Index and categorized as high/low based on the median. Modified Poisson regression was applied in the entire sample to evaluate associations of combined exposures to temperature and neighborhood disadvantage with either PTB or LBW, adjusted for covariates. We also conducted stratified analyses to explore the differential impact of these combined exposures for non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic mothers.
Relative to those experiencing lower temperatures during pregnancy and living in less deprived neighborhoods, PTB risk was elevated for women who experienced high temperatures and lived in the more deprived neighborhoods (Risk Ratio (RR), 95% Confidence Interval (CI): All Women: 3.93, 3.69–4.17; NHW: 5.25, 4.43–6.23; Hispanic 3.93, 3.63–4.24; NHB: 3.57, 3.22–3.95). For LBW, RRs were also elevated for women with these combined exposures (All Women: 3.74, 3.49–4.02; NHW: 4.19, 3.28–5.35, Hispanic: 4.12, 3.74–4.53; NHB: 3.25, 2.91–3.62).
Our study provides evidence of the racial/ethnic differences in the combined effects of high temperatures and neighborhood disadvantage on birth outcomes, highlighting the importance of considering neighborhood-level stressors in environmental and perinatal health disparities.