GH009-04
Short-term PM2.5 and cardiovascular admissions in NY State: assessing sensitivity to exposure model choice
Abstract:
Methods: We obtained county-level daily cardiovascular (CVD) admission counts from the New York (NY) Statewide Planning and Resources Cooperative System (SPARCS) and four sets of fine particulate matter (PM2.5) spatio-temporal predictions (2002-2012), including the Community Multi-scale Air Quality Model (CMAQ) and data from the Centers for Disease Control and Prevention’s Wide-ranging Online Data for Epidemiologic Research (CDC WONDER), among others. We employed overdispersed Poisson models to investigate the relationship between daily PM2.5 levels and CVD admissions, adjusting for potential confounders, separately for each state-wide PM2.5 dataset. We also repeated our analyses using PM2.5 measured at monitoring stations available in 18 of 62 counties.
Results: For three out of the four PM2.5 datasets, we observed positive, significant associations between PM2.5 and CVD. Across the modeled exposure estimates, effect estimates ranged from 0.23% (95%CI: -0.06, 0.53%) to 0.88% (95%CI: 0.68, 1.08%) per 10 µg/m3 increase in daily PM2.5. In general, CMAQ PM2.5 yielded the highest effect estimates, while the CDC dataset yielded the lowest estimates. Still higher was the effect estimate using monitored concentrations 0.96% (95%CI: 0.62, 1.30%) for the subset of counties where these data were available.
Conclusions: Effect estimates varied by a factor of almost four across methods to model exposures, likely due to varying degrees of exposure measurement error. This highlights the need for improved exposure assessment that minimizes error and includes uncertainty characterization – including uncertainty due to exposure model choice – and propagation into the health models. Nonetheless, we observed a consistently harmful association between PM2.5 and CVD admissions, regardless of model choice.