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Principal Investigator: Howard H Chang
Organization: EMORY UNIVERSITY
Fiscal Year: 2024
Award: $522,400
Funding agency: National Institute of Environmental Health Sciences
PROJECT SUMMARY/ABSTRACT
Recent studies suggest high ambient temperatures increase the risk of preterm birth (<37 completed weeks of
gestation), a leading cause of infant mortality and long-term neurological disabilities. Infants born early term
(37-38 weeks) also have more morbidity compared to full term births. Under climate projections, heat waves
are expected to increase in frequency, intensity, and duration, and many will cause increases in ambient air
pollutant concentrations. The proposed research seeks to use large existing databases and robust
methodological approaches at multiple spatial scales to test the overarching hypothesis that extreme heat
events increase the risk of preterm birth and early term birth, with stronger associations hypothesized to be
observed following heat events of longer duration and greater intensity. Using national birth record data from
the National Center for Health Statistics, we will assess these relationships in 114 large U.S. cities (covering
54% of the population) at a county-level spatial resolution over a 36-year period (1981-2016). We will
additionally obtain birth record data from eight populous and geographically representative U.S. states
(covering 40% of the population) over the period 1990-2016 to assess relationships at ZIP code or finer
resolution and to examine possible mediation of heat wave associations by accompanying changes in air
pollution levels. Meteorology will be characterized by integrating hourly data from multiple weather station
networks and satellite-resources, harnessing the strengths of each dataset to maximize spatial and temporal
coverage and minimize exposure prediction error. Ambient concentrations of 12 pollutants for the eight
selected states will be also characterized by combining Community Multiscale Air Quality Model (CMAQ)
outputs with monitor measurements. The statistical models for preterm and early term birth will account for
seasonal patterns of conception (a possible source of bias in previous studies), and two-stage analyses using
Bayesian hierarchical models will be used to combine information across study locations and assess
heterogeneity by climate region, timing of the heat event (within season or across decades), maternal
characteristics (educational attainment, race/ethnicity), and location-specific attributes (e.g., contextual
socioeconomic indicators, air conditioning prevalence, urbanicity). Precise estimation of this heterogeneity is
possible due to the exceptionally large sample, which also allows for examination of heat events defined using
higher intensity and duration thresholds than previously assessed. The multi-scale approach facilitates
assessment and propagation of uncertainty due to exposure prediction errors, spatial aggregation, and
residential mobility during pregnancy. Results can be used to inform local public health warning systems such
as heat advisories that target pregnant women with the ultimate goal of reducing early birth and its sequelae.
The study will also yield lasting benefits for future studies of climate and health through the creation of an
integrated, spatial and temporally-resolved, publically-available meteorology dataset for the continental U.S.
Terms: <0-11 years old><37 weeks completed gestation><37 weeks gestation><Age Distribution><Air><Air Conditioning><Air Pollutants><Air Pollution><Bayesian Modeling><Bayesian adaptive designs><Bayesian adaptive models><Bayesian belief network><Bayesian belief updating model><Bayesian framework><Bayesian hierarchical model><Bayesian network model><Bayesian nonparametric models><Bayesian spatial data model><Bayesian spatial image models><Bayesian spatial models><Bayesian statistical models><Bayesian tracking algorithms><Birth><Birth Records><California><Characteristics><Child><Child Youth><Children (0-21)><Chronologic Fetal Maturity><Cities><Colorado><Communities><Conceptions><County><Data><Data Bases><Data Set><Data Sources><Databases><Date of birth><Earth><Economic Income><Economical Income><Education><Educational aspects><Ethnic Origin><Ethnicity><Event><Exposure to><Fetal Age><Florida><Frequencies><Fullterm Birth><Future><Geography><Gestation><Gestational Age><Goals><Health><Heat Waves><Heterogeneity><High temperature of physical object><Hour><Humidity><Impoverished><Income><Individual><Infant><Infant Mortality><Infant Mortality Total><Investigators><Investments><Length><Location><Measurement><Measures><Mediating><Mediation><Medical><Meteorology><Methodology><Modeling><Monitor><Morbidity><Morbidity - disease rate><NCHS><National Center for Health Statistics><Negotiating><Negotiation><Neighborhoods><Neurological disability><New Jersey><Ohio><Output><Parturition><Pattern><Planet Earth><Population><Poverty><Pregnancy><Pregnant Women><Premature Birth><Prematurely delivering><Preterm Birth><Prevalence><Principal Investigator><Probabilistic Models><Probability Models><Public Health><Race><Races><Reproductive Health><Research><Research Personnel><Research Resources><Researchers><Residential Mobility><Resolution><Resources><Risk><Risk Factors><Sampling><Seasons><Socio-economic status><Socioeconomic Status><Source><Statistical Models><Surface><System><Temperature><Term Birth><Testing><Texas><Time><Uncertainty><United States National Center for Health Statistics><Urbanicity><Washington><Weather><Work><access restrictions><adverse birth outcomes><atmospheric research><atmospheric sciences><atmospheric studies><climate and health><climate exposure><climate health><climate impact><climate projections><climate region><climate zone><climate-related exposures><climate-related health><community factor><community-level factor><data base><data centers><death among infants><death in first year of life><death in infancy><death in infants><doubt><economic indicator><expectant mother><expecting mother><extreme heat><full-term birth><fullterm newborn><future climate scenario><health warning><heatwave><high temperature><incomes><infant death><infant demise><infantile death><innovate><innovation><innovative><kids><lab atmosphere><laboratory atmosphere><meteorological data><meteorological station><mortality in infants><pollutant><pregnant mothers><premature childbirth><premature delivery><preterm delivery><racial><racial background><racial origin><regional pollution><research atmosphere><resolutions><rural area><rural location><rural region><science atmosphere><science oriented atmosphere><scientific atmosphere><socio-economic><socio-economic position><socio-economically><socioeconomic position><socioeconomically><socioeconomics><statistical linear mixed models><statistical linear models><temporal measurement><temporal resolution><term newborn><time measurement><urban area><urban location><urban region><weather data><weather stations><youngster>