Exposure to traffic and left ventricular mass and function: the Multi-Ethnic Study of Atherosclerosis.
BACKGROUND
Ambient air pollution has been associated with heart failure morbidity and mortality. The mechanisms responsible for these associations are unknown but may include the effects of traffic-related pollutants on vascular or autonomic function.


OBJECTIVE
We assessed the cross-sectional relation between long-term air pollution, traffic exposures, and important end-organ measures of alterations in cardiac function-left ventricular mass index (LVMI) and ejection fraction-in the Multi-Ethnic Study of Atherosclerosis, a multicenter study of adults without previous clinical cardiovascular disease.


METHODS
A total of 3,827 eligible participants (aged 45-84 yr) underwent cardiac magnetic resonance imaging between 2000 and 2002. We estimated air pollution exposures using residential proximity to major roadways and interpolated concentrations of fine particulate matter (less than 2.5 microns in diameter). We examined adjusted associations between these exposures and left ventricular mass and function.


RESULTS
Relative to participants living more than 150 m from a major roadway, participants living within 50 m of a major roadway showed an adjusted 1.4 g/m(2) (95% CI, 0.3-2.5) higher LVMI, a difference in mass corresponding to a 5.6 mm Hg greater systolic blood pressure. Ejection fraction was not associated with proximity to major roadways. Limited variability in estimates of fine particulate matter was observed within cities, and no associations with particulate matter were found for either outcome after adjustment for center.


CONCLUSIONS
Living in close proximity to major roadways is associated with higher LVMI, suggesting chronic vascular end-organ damage from a traffic-related environmental exposure. Air pollutants or another component of roadway proximity, such as noise, could be responsible.
Van Hee
Victor C
VC
Department of Environmental and Occupational Health Sciences, University of Washington, Box 359739, Seattle, WA 98104, USA. vvanhee@u.washington.edu
Adar
Sara D
SD
Szpiro
Adam A
AA
Barr
R Graham
RG
Bluemke
David A
DA
Diez Roux
Ana V
AV
Gill
Edward A
EA
Sheppard
Lianne
L
Kaufman
Joel D
JD
D000368:Aged; D000369:Aged, 80 and over; D000397:Air Pollution / Q000009:adverse effects*; D001794:Blood Pressure; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000473:pathology*; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D044469:Racial Groups; D012111:Residence Characteristics; D013318:Stroke Volume; D013599:Systole; D014481:United States; D001335:Vehicle Emissions
D001335:Vehicle Emissions