Background: In four European cohorts, we investigated the cross-sectional association between long-term exposure to air pollution and intima-media thickness of the common carotid artery (CIMT), a preclinical marker of atherosclerosis.
Methods: Individually assigned levels of nitrogen dioxide, nitrogen oxides, particulate matter ≤ 2.5 μm (PM2.5), absorbance of PM2.5 (PM2.5abs), PM10, PMcoarse, and two indicators of residential proximity to highly trafficked roads were obtained under a standard exposure protocol (European Study of Cohorts for Air Pollution Effects—ESCAPE study) in the Stockholm area (Sweden), the Ausburg and Ruhr area (Germany), and the Girona area (Spain). We used linear regression and meta-analyses to examine the association between long-term exposure to air pollution and CIMT.
Results: The meta-analysis with 9,183 individuals resulted in an estimated increase in CIMT (geometric mean) of 0.72% (95% CI: –0.65%, 2.10%) per 5-μg/m3 increase in PM2.5 and 0.42% (95% CI: –0.46%, 1.30%) per 10–5/m increase in PM2.5abs. Living in proximity to high traffic was also positively but not significantly associated with CIMT. Meta-analytic estimates for other pollutants were inconsistent. Results were similar across different adjustment sets and sensitivity analyses. In an extended meta-analysis for PM2.5 with three other previously published studies, a 0.78% (95% CI: –0.18%, 1.75%) increase in CIMT was estimated for a 5-μg/m3 contrast in PM2.5.
Conclusions: Using a standardized exposure and analytical protocol in four European cohorts, we found that cross-sectional associations between CIMT and the eight ESCAPE markers of long-term residential air pollution exposure did not reach statistical significance. The additional meta-analysis of CIMT and PM2.5 across all published studies also was positive but not significant.
1Swiss Tropical and Public Health Institute, Basel, Switzerland; 2University of Basel, Basel, Switzerland; 3Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany; 4IUF–Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany; 5Unit of Environmental Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; 6Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; 7CIBER Epidemiologia y Salud Pública (CIBERESP), Spain; 8Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands; 9Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, the Netherlands; 10Environment Science Center, University of Augsburg, Augsburg, Germany; 11Dipartimento di Scienze Farmacologiche e Biomolecolari, Università di Milano, Milan, Italy; 12Centro Cardiologico Monzino, IRCCS, Milan, Italy; 13Cardiovascular Epidemiology and Genetics, IMIM, Barcelona, Spain; 14Department of Internal Medicine II–Cardiology, University of Ulm, Medical Center, Ulm, Germany; 15Division of Cardiovascular Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; 16Centre for Environmental Policy, Imperial College London, United Kingdom; 17German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Institute for Biometrics and Epidemiology, Düsseldorf, Germany; 18University of Montreal Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada; 19Diabetes Zentrum, Medizinische Klinik und Poliklinik IV–Campus Innenstadt, Klinikum der Ludwig-Maximilians-Universität, München, Germany; 20Clinical Cooperation Group Diabetes, Ludwig-Maximilians-Universität München and Helmholtz Zentrum München, München, Germany; 21Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University of Leipzig, Leipzig, Germany; 22Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
Recommended Citation:
Laura Perez,1,2 Kathrin Wolf,et al. Air Pollution and Atherosclerosis: A Cross-Sectional Analysis of Four European Cohort Studies in the ESCAPE Study[J]. Environmental Health Perspectives,2015-01-01,Volume 123(Issue 6):597