Changes in residential proximity to road traffic and the risk of death from coronary heart disease.
BACKGROUND
Residential proximity to road traffic is associated with increased coronary heart disease (CHD) morbidity and mortality. It is unknown, however, whether changes in residential proximity to traffic could alter the risk of CHD mortality.


METHODS
We used a population-based cohort study with a 5-year exposure period and a 4-year follow-up period to explore the association between changes in residential proximity to road traffic and the risk of CHD mortality. The cohort comprised all residents aged 45-85 years who resided in metropolitan Vancouver during the exposure period and without known CHD at baseline (n = 450,283). Residential proximity to traffic was estimated using a geographic information system. CHD deaths during the follow-up period were identified using provincial death registration database. The data were analyzed using logistic regression.


RESULTS
Compared with the subjects consistently living away from road traffic (>150 m from a highway or >50 m from a major road) during the 9-year study period, those consistently living close to traffic (<or=150 m from a highway or <or=50 m from a major road) had the greatest risk of CHD mortality (relative risk [RR] = 1.29 [95% confidence interval = 1.18-1.41]). By comparison, those who moved closer to traffic during the exposure period had less increased risk than those who were consistently exposed (1.20 [1.00-1.43]), and those who moved away from traffic had even less increase in the risk (1.14 [0.95-1.37]). All analyses were adjusted for baseline age, sex, pre-existing comorbidities (diabetes, chronic obstructive pulmonary disease, hypertensive heart disease), and neighborhood socioeconomic status.


CONCLUSIONS
Living close to major roadways was associated with increased risk of coronary mortality, whereas moving away from major roadways was associated with decreased risk.
Gan
Wen Qi
WQ
School of Environmental Health, The University of British Columbia, Vancouver, BC, Canada.
Tamburic
Lillian
L
Davies
Hugh W
HW
Demers
Paul A
PA
Koehoorn
Mieke
M
Brauer
Michael
M
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000397:Air Pollution / Q000009:adverse effects; D001955:British Columbia / Q000453:epidemiology; D015331:Cohort Studies; D003327:Coronary Disease / Q000209:etiology / Q000401:mortality*; D003993:Dibutyl Phthalate; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles / Q000706:statistics & numerical data*; D012307:Risk Factors; D012737:Sex Factors; D012959:Socioeconomic Factors
D003993:Dibutyl Phthalate