| Abstrakt: |
Existing studies of the association between air pollution, aeroallergens and emergency department (ED) visits have generally examined the effects of a few pollutants or aeroallergens on individual conditions such as asthma or chronic obstructive pulmonary disease. In this study, we considered a wide variety of respiratory and cardiac conditions and an extensive set of pollutants and aeroallergens, and utilized prospectively collected information on possible effect modifiers which would not normally be available from purely administrative data. The association between air pollution, aeroallergens and cardiorespiratory ED visits (n=19,821 ) was examined for the period 1992 to 1996 using generalized additive models. ED visit, air pollution and aeroallergen time series were prefiltered using LOESS smoothers to minimize temporal confounding, and a parsimonious model was constructed to control for confounding by weather and day of week. Multipollutant and multi-aeroallergen models were constructed using stepwise procedures and sensitivity analyses were conducted by season, diagnosis, and selected individual characteristics or effect modifiers. In single-pollutant models, positive effects of all pollutants but NO[SUB2] and COH were observed on asthma visits, and positive effects on all respiratory diagnosis groups were observed for O[SUB3], SO[SUB2], PM[SUB10], PM[SUB2.5], and SO[SUB4,SUP2-] . Among cardiac conditions, only dysrhythmia visits were positively associated with all measures of particulate matter. In the final year-round multipollutant models, a 20.9% increase in cardiac ED visits was attributed to the combination of O[SUB3] (16.0%, 95% CI 2.8-30.9) and SO[SUB2] (4.9%, 95% CI 1.7-8.2) at the mean concentration of each pollutant. In the final multipollutant model for respiratory visits, O[SUB3] accounted for 3.9% of visits (95% CI 0.8-7.2), and SO[SUB2] for 3.7% (95% CI 1.5-6.0), whereas a weak, negative association was observed with NO[SUB2]. In... [ABSTRACT FROM AUTHOR] |
