Cardiovascular and Cerebrovascular Mortality Associated With Acute Exposure to PM 2.5 in Mexico City.

BACKGROUND AND PURPOSE: Acute exposure to particulate matter with aerodynamic diameter <2.5 μm (PM2.5 ) is associated with acute cardiovascular and cerebrovascular mortality. The aim of this study was to evaluate these associations with specific causes of cardiovascular and cerebrovascular mortality in Mexico City.

METHODS: We obtained daily mortality records for Mexico City from 2004 to 2013 for cardiovascular and cerebrovascular causes in people ≥25 and ≥65 years old. Exposure to PM2.5 was assessed with daily estimates from a new hybrid spatiotemporal model using satellite measurements of aerosol optical depth PM2.5 and compared to ground level PM2.5 measurements with missing data estimated with generalized additive models PM2.5 . We fitted Poisson regression models with distributed lags for all mortality outcomes.

RESULTS: An increase of 10 µg/m3 in aerosol optical depth PM2.5 was associated with increased cardiovascular (1.22%; 95% confidence interval, 0.17-2.28) and cerebrovascular mortality (3.43%; 95% confidence interval, 0.10-6.28) for lag days 0 to 1 (lag 0-1). Stronger effects were identified for hemorrhagic stroke and people ≥65 years. Associations were slightly smaller using generalized additive models PM2.5 .

CONCLUSIONS: These results support the evidence that acute exposure to PM2.5 is associated with increased risk of specific cardiovascular and cerebrovascular mortality causes.