Air pollution and mortality in Latin America: the role of education.
BACKGROUND
People with less education in Europe, Asia, and the United States are at higher risk of mortality associated with daily and longer-term air pollution exposure. We examined whether educational level modified associations between mortality and ambient particulate pollution (PM10) in Latin America, using several timescales.


METHODS
The study population included people who died during 1998-2002 in Mexico City, Mexico; Santiago, Chile; and São Paulo, Brazil. We fit city-specific robust Poisson regressions to daily deaths for nonexternal-cause mortality, and then stratified by age, sex, and educational attainment among adults older than age 21 years (none, some primary, some secondary, and high school degree or more). Predictor variables included a natural spline for temporal trend, linear PM10 and apparent temperature at matching lags, and day-of-week indicators. We evaluated PM10 for lags 0 and 1 day, and fit an unconstrained distributed lag model for cumulative 6-day effects.


RESULTS
The effects of a 10-microg/m increment in lag 1 PM10 on all nonexternal-cause adult mortality were for Mexico City 0.39% (95% confidence interval = 0.13%-0.65%); São Paulo 1.04% (0.71%-1.38%); and for Santiago 0.61% (0.40%-0.83%). We found cumulative 6-day effects for adult mortality in Santiago (0.86% [0.48%-1.23%]) and São Paulo (1.38% [0.85%-1.91%]), but no consistent gradients by educational status.


CONCLUSIONS
PM10 had important short- and intermediate-term effects on mortality in these Latin American cities, but associations did not differ consistently by educational level.
O'Neill
Marie S
MS
Departments of Epidemiology and Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA. marieo@umich.edu
Bell
Michelle L
ML
Ranjit
Nalini
N
Cifuentes
Luis A
LA
Loomis
Dana
D
Gouveia
Nelson
N
Borja-Aburto
Victor H
VH
D000328:Adult; D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D001938:Brazil / Q000453:epidemiology; D002677:Chile / Q000453:epidemiology; D002947:Cities; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D008954:Models, Biological; D009026:Mortality; D052638:Particulate Matter / Q000009:adverse effects* / Q000032:analysis; D012306:Risk; D014887:Weather; D055815:Young Adult
D052638:Particulate Matter