Hospital admissions and mortality: association with air pollution in São Paulo, Brazil, 1993 to 1997

Abstract

OBJECTIVE: To investigate short-term effects of air pollution on respiratory morbidity of children under 15 and elderly mortality. METHODS: The study was carried out in the city of São Paulo, Brazil. Daily hospital admissions due to respiratory conditions in children under 15 and mortality of adults over 64 years of age were obtained for the period ranging from 1993 to 1997. Daily levels of PM10, CO and O3 were collected for the same period. Poisson regression analysis was used in generalized additive models, which were adjusted for temporal trends, seasonality, day of the week, temperature and relative humidity as well as serial autocorrelation. RESULTS: A 10th to 90th percentile variation of pollutants was significantly associated with respiratory admissions of children and PM10 (%RR=10.0), CO (%RR=6.1), and O3 (%RR=2.5). Similar results were observed for mortality in elderly people and PM10 (%RR=8.1) and CO (%RR=7.9). CONCLUSIONS: The study results are consistent with other studies showing an association of short-term variations of air pollution and increase of morbidity and mortality in large urban centers.