Ambient air pollution and preterm birth in the environment and pregnancy outcomes study at the University of California, Los Angeles

Ritz, B; Wilhelm, M; Hoggatt, KJ; Ghosh, JK

HERO ID

96146

Reference Type

Journal Article

Year

2007

Language

English

PMID

17675655

HERO ID 96146
In Press No
Year 2007
Title Ambient air pollution and preterm birth in the environment and pregnancy outcomes study at the University of California, Los Angeles
Authors Ritz, B; Wilhelm, M; Hoggatt, KJ; Ghosh, JK
Journal American Journal of Epidemiology
Volume 166
Issue 9
Page Numbers 1045-1052
Abstract The authors conducted a case-control survey nested within a birth cohort and collected detailed risk factor information to assess the extent to which residual confounding and exposure misclassification may impact air pollution effect estimates. Using a survey of 2,543 of 6,374 women sampled from a cohort of 58,316 eligible births in 2003 in Los Angeles County, California, the authors estimated with logistic regression and two-phase models the effects of pregnancy period-specific air pollution exposure on the odds of preterm birth. For the first trimester, the odds of preterm birth consistently increased with increasing carbon monoxide exposures and also at high levels of exposure to particulate matter less than or equal to 2.5 µm in diameter (>21.4 µg/m3), regardless of type of data (cohort/sample) or covariate adjustment (carbon monoxide exposures of >1.25 ppm increased the odds by 21-25%). Women exposed to carbon monoxide above 0.91 ppm during the last 6 weeks of pregnancy experienced increased odds of preterm birth. Crude and birth certificate covariate-adjusted results for carbon monoxide differed from each other. However, further adjustment for risk factors assessed in the survey did not change effect estimates for short-term pollutant averages appreciably, except for time-activity patterns, which strengthened the observed associations. These results confirm the importance of reducing exposure misclassification when evaluating the effect of traffic-related pollutants that vary spatially.
Doi 10.1093/aje/kwm181
Pmid 17675655
Wosid WOS:000250400700008
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000250400700008
Is Public Yes
Language Text English
Keyword air pollution; confounding factors (epidemiology); misclassification; premature birth; two-phase regression; vehicle emissions
Is Qa No