A census tract-level assessment of social determinants of health, traffic exposure, and asthma exacerbations in New York State's Medicaid Population (2005-2015).

This study aims to evaluate the association between social determinants, environmental exposure metrics, and the risk of asthma emergency department (ED) visits in the New York State (NYS) Medicaid population using small-area analysis. Traffic densities for each census tract in NYS were calculated using the length of road segments within each tract and total area of the tract to produce a measure of average number of vehicles per square meter per day. Data on social determinants of health including internal and external environments and other demographic factors were obtained from various sources. Poisson regression analyses were conducted to identify significant factors associated with asthma ED visits in Medicaid claim and encounter data for years 2005-2015. High traffic density in NYS excluding New York City (NYC) correlated with increased risk of asthma ED visits (RR 1.69; 95% CI: 1.42, 2.00), mitigated by adjusting for environmental and social determinants (RR 1.00; 95% CI: 0.85, 1.19). Similar trends were observed in NYC only (RR 1.19; 95% CI: 1.00, 1.41), with the adjusted risk remaining elevated (RR 1.14; 95% CI: 0.98, 1.33) albeit not statistically significant. Living in census tracts with high concentrated disadvantage index, high proportions of minorities, and less green space predicted higher asthma ED visits. We mapped predicted rates and model residuals to identify areas of high risk. Our results support previous findings that environmental and social risk factors in poor and urban areas contribute to asthma exacerbations in the NYS Medicaid population, even if they may not necessarily contribute to its development.