Acute Air Pollution Exposure and Blood Pressure at Delivery Among Women With and Without Hypertension
Year of Publication
Mannisto, T; Mendola, P; Liu, D; Leishear, K; Sherman, S; Laughon, SK
Am J Hypertens
Air pollution; blood pressure; epidemiology; hypertension; Pregnancy
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 mum 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.