Modeling the effect of air pollution on hospitalizations in Sao Paulo City (2000-2010)

Abstract

The purpose of this study is to investigate the effects of air pollution on respiratory and cardiovascular health with respect to age in the municipality of Sao Paulo, Brazil. Daily data for this study were obtained from publicly available pollution monitoring stations and hospitalization records for Sao Paulo from 2000 to 2010. Hospitalizations were sorted by age group: <5 years, 5 to 14 years, 15 to 29 years, 30 to 64 years, and 65 years and older. In order to account for spatial heterogeneity in pollution and population, focus areas of study were set as areas within distance 1.5 km from a pollution monitoring station. Temporal effects of day of the week, month, and year were also analyzed for each of the variables. Using a fixed effects Poisson regression model with particulate matter, PM10, concentration as an indicator variable for pollution, the effect on expected hospitalizations was investigated, while accounting for spatial and temporal variation. Additional analysis of gender-specific age groups was also conducted. The main result of the study shows a highly significant effect of PM10 concentration on children younger than 5 years old, with a 1.37% increase in expected respiratory hospitalizations with each 10 μg/m3 increase in PM10 concentration. The results provide some support for the effect of pollution on gender-specific age groups. Further analysis on gender-specific mechanisms of pollution on health is recommended to analyze the differences in more detail.