Risk factors in cardiovascular disease mortality associated with high exposure to vehicular traffic.

OBJECTIVE: To identify areas and risk factors in cardiovascular disease (CD) mortality associated with air pollution from high exposure to vehicular traffic.

METHODS: Cross-sectional study of CD mortality in 2,617 individuals aged 45-85 years living in the urban area of Cuiabá and Várzea Grande, Mato Grosso State, Brazil, between 2009 and 2011. We used the residential proximity of up to 150 meters to a roadway of great vehicle flow as a proxy of high exposure to air pollution from vehicular traffic. The association between age, gender, income, and traffic intensity with vehicular traffic exposure was assessed through the multiple logistic regression. We conducted stratified analyses to observe the influence of seasons and groups of causes. We used Bernoulli's spatial model of probability to identify high-risk clusters.

RESULTS: Risk factors for CD mortality associated with high exposure to vehicular traffic were: living in census tracts with very unequal income (OR = 1.78; 95%CI 1.36 - 2.33), heavy traffic (OR = 1.20; 95%CI 1.01 - 1.43), and female gender (OR = 1.18; 95%CI 1.01 - 1.38). The CD mortality risk increases about 10% during the dry season period. We identified nine areas of risk.

CONCLUSION: High exposure to traffic is associated with CD mortality in Cuiabá and Várzea Grande. Income inequality, traffic intensity, and female gender presented as the main determiners for this exposure. The dry season period enhances the effects of traffic exposure.