Association between asthma-related emergency department visits, meteorological measurements, and air quality concentrations in the Bronx (2001-2008)

Methods: We previously investigated AREDV at two Bronx hospitals (Montefiore-Weiler and Moses) from 1/2001 to 12/2008, and found that a spring increase in AREDV closely correlated with high tree pollen counts. In this study we analyzed the association between AREDV and other indices of air quality including pollutants (nitrogen dioxide-NO2, sulfur dioxide-SO2) and meteorological factors (precipitation, atmospheric pressure, humidity, temperature). Daily AREDV numbers were obtained through the CLG software. Daily counts for pollutants and meteorological variables were obtained through the National Climatic Data Center. Data were statistically analyzed and graphed as daily values.

Results: From 2001-2008, there were a total of 42,065 AREDV at the two hospitals. We consistently observed three distinct peaks of AREDV: January (winter), May (spring), and November (fall). The winter peak of AREDV correlated with increased NO2 and increased SO2. High precipitation levels in the fall closely associated with the fall peak of AREDV. We did not observe an association between atmospheric pressure or humidity and AREDV. High temperatures in the summer were associated with decreased AREDV.

Conclusions: There is a consistent association between the winter peak of AREDV and increased winter NO2 and SO2 concentrations. Increased precipitation closely associated with the fall peak of AREDV. These findings may help to predict periods of increased asthma exacerbations, although multivariate and prospective analyses are necessary.