Atmospheric Temperature & Pollen Counts Impact New York City Asthma ER Visits

Abstract

RATIONALE: Global warming leads to temperature changes associated with increased particulate matter air pollution, a trigger for asthma attacks. Pollen counts are temperature sensitive, increasing with elevated ambient conditions. We examined the separate and combined effects of temperature and pollen counts on asthma emergency room visits at a New York City Hospital. METHODS: Temperature data were recorded at JFK Airport (1960-present). Particulate matter (PM2.5) air pollution, the concentration of 2.5 micron-sized particles per cubic meter of air, were from the Bronx, Queens, and Manhattan (2006-9). Pollen counts were measured in Brooklyn (AAAAI databank-2008). Asthma emergency room visits were from Lincoln Hospital (Bronx; 2007-9). Relations among these data were determined based on correlation coefficients. RESULTS: 1. Temperature in 2007 correlated with 2008 (r = 0.98) as did monthly asthma emergency room visits (r = 0.89), indicating the relative stability of the seasonal changes in both temperature and asthma "incidents." 2. Asthma emergency room visits and temperature (2007-8) were inverse correlated (r = - 0.56, p <.01). 3. Asthma emergency room visits were correlated with pollen counts (r = 0.81, p <.03). 4. Asthma-related hospital discharge rates in the Bronx peaked in 2003, coinciding with the decrease of temperature that year. CONCLUSIONS An environmental contribution to asthma emergency room visits related to the complex interplay of temperature and pollen supports the concept that global warming has an impact on asthma.