Short-term exposure to ambient air pollution and circulating biomarkers of endothelial cell activation: The Framingham Heart Study.
BACKGROUND
Short-term exposure to air pollution has been associated with cardiovascular events, potentially by promoting endothelial cell activation and inflammation. A few large-scale studies have examined the associations and have had mixed results.


METHODS
We included 3820 non-current smoking participants (mean age 56 years, 54% women) from the Framingham Offspring cohort examinations 7 (1998-2001) and 8 (2005-2008), and Third Generation cohort examination 1 (2002-2005), who lived within 50 km of a central monitoring station. We calculated the 1- to 7-day moving averages of fine particulate matter (PM2.5), black carbon (BC), sulfate (SO42-), nitrogen oxides (NOx), and ozone before examination visits. We used linear mixed effect models for P-selectin, monocyte chemoattractant protein 1 (MCP-1), intercellular adhesion molecule 1, lipoprotein-associated phospholipase A2 activity and mass, and osteoprotegerin that were measured up to twice, and linear regression models for CD40 ligand and interleukin-18 that were measured once, adjusting for demographics, life style and clinical factors, socioeconomic position, time, and meteorology.


RESULTS
We found negative associations of PM2.5 and BC with P-selectin, of ozone with MCP-1, and of SO42- and NOx with osteoprotegerin. At the 5-day moving average, a 5 µg/m3 higher PM2.5 was associated with 1.6% (95% CI: - 2.8, - 0.3) lower levels of P-selectin; a 10 ppb higher ozone was associated with 1.7% (95% CI: - 3.2, - 0.1) lower levels of MCP-1; and a 20 ppb higher NOx was associated with 2.0% (95% CI: - 3.6, - 0.4) lower levels of osteoprotegerin.


CONCLUSIONS
We did not find evidence of positive associations between short-term air pollution exposure and endothelial cell activation. On the contrary, short-term exposure to higher levels of ambient pollutants were associated with lower levels of P-selectin, MCP-1, and osteoprotegerin in the Framingham Heart Study.
['Li|Wenyuan|W|', 'Dorans|Kirsten S|KS|', 'Wilker|Elissa H|EH|', 'Rice|Mary B|MB|', 'Ljungman|Petter L|PL|', 'Schwartz|Joel D|JD|', 'Coull|Brent A|BA|', 'Koutrakis|Petros|P|', 'Gold|Diane R|DR|', 'Keaney|John F|JF|', 'Vasan|Ramachandran S|RS|', 'Benjamin|Emelia J|EJ|', 'Mittleman|Murray A|MA|']
D000393:Air Pollutants D000397:Air Pollution D015415:Biomarkers D042783:Endothelial Cells D004781:Environmental Exposure D005260:Female D006801:Humans D008137:Longitudinal Studies D008297:Male D008875:Middle Aged D052638:Particulate Matter
Air pollution Biomarker Inflammation Endothelial dysfunction Environment Epidemiology