Air pollution and emergency room visits due to pneumonia and influenza in Sao Paulo, Brazil

Objective A time series was developed to investigate the effect of air pollution levels on morbidity elite to respiratory diseases such as pneumonia and influenza among elderly people from 1996 to 1998. Methods Daily data on emergency room visits was collected tit the university clinics hospital in Sao Paulo, Brazil. Daily levels of CO. NO2, O-3, SO2 and PM10 were obtained from the State Environmental Agency. Daily measures of temperature and relative humidity were obtained from the Institute of Astronomy and Geophysics of the University of Sao Paulo. Generalized additive Poisson regression models were used to assess the relationship between pneumonia and influenza ar 1 air pollution, using the number of emergency room visits as dependent variable and the average daily levels of each pollutant as independent variables. The models were estimated and adjusted by seasonality (non-parametrie function), weather, weekdays. motor vehicle circulation curbs periods and daily numbers of non-respiratory hospital admissions. Results The pollutants O-3 and SO2 showed a statistical association with pneumonia and influenza. These associations remained robust when control variables were included. An interquartile range for O-3 (38.80 mug/m(3)) and SO2 (15.05 mug/m(3)) increased in 8.07% and 14.5%, respectively the number of emergency room visits due to pneumonia and influenza. Conclusion The study results suggest that air pollution in the city of Sao Paulo may promote adverse health effects in elderly people.