Admission to neonatal intensive care in relation to satellite-based estimates of NO2 and PM2.5 in the United States, 2018

Abstract

BACKGROUND AND AIM: Prior work noted an increased risk of admission to neonatal intensive care units (NICU) associated with acute exposure to air pollution in 12 clinical centers across the US, 2002-2008. We aimed to assess chronic exposure in relation to NICU admission. METHODS: We obtained 2018 birth certificate data for the US, including all counties with populations greater than 100,000. County-level air pollution data were derived from OMI (NO2), a combination of the MISR, MODIS, and SeaWIFS instruments (PM2.5) and downscaled CMAQ model data were assembled for ozone. We conducted both single and multi-pollutant logistic models for season of birth (winter: December to February; spring: March to May; summer: June to August; and fall: September to November). Exposure was characterized in quartiles with the lowest as reference. The risk of NICU admission among singletons (n=3,644,722) in relation to air pollution exposure was assessed using logistic regression with generalized estimating equations (to account for correlated data within county) and adjusted for maternal age, race, education, body mass index and infant sex. RESULTS: NICU admission (8.1% of births) was significantly increased in relation to NO2 during all seasons in both single and multi-pollutant models. Adjusted odds ratios (OR) ranged from 1.21 to 1.28 for the highest quartile of exposure in single-pollutant models and 1.13 to 1.27 in multi-pollutant models. The highest quartile of PM2.5 was significantly associated with increased NICU risk in winter (single-pollutant OR=1.27, multi-pollutant OR=1.13), spring (single-pollutant OR=1.14) and summer (single-pollutant OR= 1.12). The highest quartile of ozone was associated with increased risk in the single pollutant model for summer (OR= 1.15) and reduced risk in fall and winter; all multipollutant models for ozone were non-significant. CONCLUSIONS: Consistent with our prior work, ambient air pollutants, particularly NO2 and PM2.5, are associated with increased risk of NICU admission.