Influence of socioeconomic conditions on air pollution adverse health effects in elderly people: an analysis of six regions in São Paulo, Brazil.
OBJECTIVE
To evaluate if the effects of particulate matter (PM(10)) on respiratory mortality of elderly people are affected by socioeconomic status.


METHODS
Time series studies. The daily number of elderly respiratory deaths were modelled in generalised linear Poisson regression models controlling for long term trend, weather, and day of the week, from January 1997 to December 1999, in six different regions of São Paulo City, Brazil. The regions were defined according to the proximity of air pollution monitoring stations. Three socioeconomic indicators were used: college education, monthly income, and housing.


RESULTS
For a 10 micro g/m(3) increase in PM(10), the percentage increase in respiratory mortality varied from 1.4% (95% CI 5.9 to 8.7) to 14.2% (95% CI 0.4 to 28.0). The overall percentage increase in the six regions was 5.4% (95% CI 2.3 to 8.6). The effect of PM(10) was negatively correlated with both percentage of people with college education and high family income, and it was positively associated with the percentage of people living in slums.


CONCLUSIONS
These results suggest that socioeconomic deprivation represents an effect modifier of the association between air pollution and respiratory deaths.
Martins
M C H
MC
São Paulo City Health Departments, Brazil.
Fatigati
F L
FL
Véspoli
T C
TC
Martins
L C
LC
Pereira
L A A
LA
Martins
M A
MA
Saldiva
P H N
PH
Braga
A L F
AL
D000368:Aged; D000393:Air Pollutants / Q000633:toxicity; D000397:Air Pollution / Q000009:adverse effects*; D001938:Brazil / Q000453:epidemiology; D015987:Effect Modifier, Epidemiologic; D006801:Humans; D008875:Middle Aged; D016012:Poisson Distribution; D012120:Respiration Disorders / Q000209:etiology / Q000401:mortality*; D012923:Social Class; D012959:Socioeconomic Factors; D014504:Urban Health / Q000706:statistics & numerical data; D001335:Vehicle Emissions / Q000633:toxicity
D000393:Air Pollutants; D001335:Vehicle Emissions