Acute air pollution exposure and blood pressure at delivery among women with and without hypertension.

Publication Type
Journal Article
Year of Publication
Männistö, Tuija; Mendola, Pauline; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S Katherine
Am J Hypertens
Date Published
2015 Jan
Adult; Air Pollutants; blood pressure; Case-Control Studies; Delivery, Obstetric; Environmental Exposure; Environmental Monitoring; Female; Humans; Hypertension, Pregnancy-Induced; Logistic Models; Odds Ratio; Particle Size; Particulate Matter; Patient Admission; Pregnancy; Risk Factors; Severity of Illness Index; Time Factors; United States; Young Adult

BACKGROUND: Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known.

METHODS: We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002-2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect.

RESULTS: Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%-4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units.

CONCLUSIONS: Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission.