Association between long-term exposure to traffic particles and blood pressure in the Veterans Administration Normative Aging Study
- Joel Schwartz1,2,
- Stacey E Alexeeff2,3,
- Irina Mordukhovich4,
- Alexandros Gryparis3,
- Pantel Vokonas5,
- Helen Suh2,
- Brent A Coull3
- 1Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA
- 2Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
- 3Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts, USA
- 4Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA
- 5Department of Medicine, VA Normative Aging Study, Veterans Affairs Boston Healthcare System, Boston University School of Medicine, Boston, Massachusetts, USA
- Correspondence to Stacey E Alexeeff, Department of Biostatistics, Harvard School of Public Health, 677 Huntington Ave, Building 2, 4th floor, Boston, MA 02215, USA;
- Accepted 4 February 2012
- Published Online First 1 March 2012
Objectives Particulate air pollution is associated with cardiovascular events, but the mechanisms are not fully understood. The main objective was to assess the relationship between long-term exposure to traffic-related air pollution and blood pressure (BP).
Methods The authors used longitudinal data from 853 elderly men participating in the Veterans Administration Normative Aging Study, followed during 1996–2008. Long-term average exposures to traffic particles were created from daily predictions of black carbon (BC) exposure at the geocoded address of each subject, using a validated spatiotemporal model based on ambient monitoring at 82 Boston-area locations. The authors examined the association of these exposures with BP using a mixed model. The authors included the following covariates: age, body mass index, smoking, alcohol, fasting glucose, creatinine clearance, use of cardiovascular medication, education, census-level poverty, day of week and season of clinical visit.
Results The authors found significant positive associations between 1-year average BC exposure and both systolic and diastolic blood pressure. An IQR increase in 1-year average BC exposure (0.32 μg/m3) was associated with a 2.64 mm Hg increase in systolic blood pressure (95% CI 1.47 to 3.80) and a 2.41 mm Hg increase in diastolic blood pressure (95% CI 1.77 to 3.05).
Conclusions Long-term exposure to traffic particles is associated with increased BP, which may explain part of the association with myocardial infarctions and cardiovascular deaths reported in cohort studies.
- Air pollution
- exposure assessment
- longitudinal studies
- air pollution
Funding This work was supported by the National Institute of Environmental Health Sciences grants ES015172-01 and ES00002 and the US Environmental Protection Agency grants RD-832416-01 and RD-834798-01. The Normative Ageing Study is supported by the Cooperative Studies Program/Epidemiology Research and Information Center of the US Department of Veterans Affairs and is a component of the Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC), Boston, MA.
Competing interests None.
Ethics approval Human Subjects Committee.
Provenance and peer review Not commissioned; externally peer reviewed.