RESUMEN
Many studies have shown an association between ozone and mortality. However, little data is available on the cumulative effects of ozone on health. A time-series analysis using a Poisson regression was used to measure the impact of ozone on non-traumatic mortality in Wallonia over the period 2000-2012. Initially, a single-lag model was tested. Then a distributed-lag non-linear model was used in order to verify the cumulative effects of ozone on mortality. Our study confirms the existence of an association between ozone and mortality. The linear model without threshold shows a higher sensitivity in persons aged 75 and over (ERR = 0.7, 95 % CI: 0.4; 1.0 %) compared to younger people (ages 25-74) (ERR = 0.2, 95 % CI: - 0.2; 0.6 %). Taking cumulative effects into account, men and women aged 25-74 have an ozone sensitivity equivalent to those over 75.
Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/efectos adversos , Mortalidad , Ozono/efectos adversos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Bélgica/epidemiología , Monitoreo del Ambiente , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Distribución de Poisson , Factores SexualesRESUMEN
The case-crossover design is frequently used for analyzing the acute health effects of air pollution. Nevertheless, only a few studies compared different methods for selecting control periods. In this study, the bidirectional method and three time-stratified methods were used to estimate the association between air pollution and acute myocardial infarction (AMI) in Charleroi, Belgium, during 1999-2008. The strongest associations between air pollution and AMI were observed for PM10 and NO(2) during the warm period, OR = 1.095 (95 % CI: 1.003-1.169) and OR = 1.120 (95 % CI: 1.001-1.255), respectively. The results of this study reinforce the evidence of the acute effects of air pollution on AMI, especially during the warm season. This study suggests that the different methods of case-crossover study design are suitable to studying the association between acute events and air pollution. The temperature-stratified design is useful to exclude temperature as a potential confounder.