Traffic air pollution and mortality from cardiovascular disease and all causes: a Danish cohort study

Raaschou-Nielsen Ole, Andersen Zorana, Jensen Steen, Ketzel Matthias, Sørensen Mette, Hansen Johnni, Loft Steffen, Tjønneland Anne, Overvad, Overvad Kim

Description

Traffic air pollution has been linked to cardiovascular mortality, which might be due to co-exposure to road traffic noise. Further, personal and lifestyle characteristics might modify any association. Methods We followed up 52 061 participants in a Danish cohort for mortality in the nationwide Register of Causes of Death, from enrollment in 1993–1997 through 2009, and traced their residential addresses from 1971 onwards in the Central Population Registry. We used dispersion-modelled concentration of nitrogen dioxide (NO 2 ) since 1971 as indicator of traffic air pollution and used Cox regression models to estimate mortality rate ratios (MRRs) with adjustment for potential confounders. Results Mean levels of NO 2 at the residence since 1971 were significantly associated with mortality from cardiovascular disease (MRR, 1.26; 95% confidence interval [CI], 1.06–1.51, per doubling of NO 2 concentration) and all causes (MRR, 1.13; 95% CI, 1.04–1.23, per doubling of NO 2 concentration) after adjustment for potential confounders. For participants who ate < 200 g of fruit and vegetables per day, the MRR was 1.45 (95% CI, 1.13–1.87) for mortality from cardiovascular disease and 1.25 (95% CI, 1.11–1.42) for mortality from all causes. Conclusions Traffic air pollution is associated with mortality from cardiovascular diseases and all causes, after adjustment for traffic noise. The association was strongest for people with a low fruit and vegetable intake.

Sujets

• Traffic
• Air pollution
• Cohort

Informations

• Publié par: biomed
• Publié le: 01 janvier 2012
• Nombre de lectures: 13
• Langue: English

Extrait

RaaschouNielsenet al. Environmental Health2012,11:60 http://www.ehjournal.net/content/11/1/60

R E S E A R C HOpen Access Traffic air pollution and mortality from cardiovascular disease and all causes: a Danish cohort study 1* 1,23 31 Ole RaaschouNielsen, Zorana Jovanovic Andersen, Steen Solvang Jensen , Matthias Ketzel , Mette Sørensen , 1 41 5 Johnni Hansen , Steffen Loft , Anne Tjønnelandand Kim Overvad

Abstract Background:Traffic air pollution has been linked to cardiovascular mortality, which might be due to coexposure to road traffic noise. Further, personal and lifestyle characteristics might modify any association. Methods:We followed up 52 061 participants in a Danish cohort for mortality in the nationwide Register of Causes of Death, from enrollment in 1993–1997 through 2009, and traced their residential addresses from 1971 onwards in the Central Population Registry. We used dispersionmodelled concentration of nitrogen dioxide (NO 2 ) since 1971 as indicator of traffic air pollution and used Cox regression models to estimate mortality rate ratios (MRRs) with adjustment for potential confounders. Results:Mean levels of NO 2 at the residence since 1971 were significantly associated with mortality from cardiovascular disease (MRR, 1.26; 95% confidence interval [CI], 1.06–1.51, per doubling of NO 2 concentration) and all causes (MRR, 1.13; 95% CI, 1.04–1.23, per doubling of NO 2 concentration) after adjustment for potential confounders. For participants who ate< 200g of fruit and vegetables per day, the MRR was 1.45 (95% CI, 1.13–1.87) for mortality from cardiovascular disease and 1.25 (95% CI, 1.11–1.42) for mortality from all causes. Conclusions:Traffic air pollution is associated with mortality from cardiovascular diseases and all causes, after adjustment for traffic noise. The association was strongest for people with a low fruit and vegetable intake. Keywords:Traffic, Air pollution, Cardiovascular mortality, Total mortality, Cohort

Background Although several recent studies have shown associations between longterm exposure to trafficrelated air pollu tion and mortality from cardiovascular disease and all causes [19], several questions remain open. Exposure to road traffic noise might explain the observed associations, as this has been associated with morbidity and mortality from cardiovascular disease [10]. Furthermore, air pollu tion could affect the risk for cardiovascular disease through mechanisms involving systemic oxidative stress and inflammation, which could drive atherosclerosis pro gression and other longterm effects as well as serve as triggers of events through changes in vascular function, thrombogenecity, plaque stability and autonomic balance

* Correspondence: [e-mail] 1 Danish Cancer Society Research Center, Copenhagen, Denmark Full list of author information is available at the end of the article

[11]; the amount of fruit and vegetables in the diet, containing antioxidants and related compounds, might therefore modify the effect of air pollution as suggested for shortterm mortality in a casecrossover study in Hongkong [12]. People with preexisting cardiovascular disease or diabetes mellitus might be particularly suscep tible to the effects of air pollution on cardiovascular mortality. Exposure to air pollution decades back in time and perhaps throughout life might be important in the development of chronic cardiovascular disease [13]. Most previous studies of longterm exposure, however, have focused on the addresses of participants at baseline, and few studies have investigated exposure assessed from address history [4,6,14,15]. We report here the results of a Danish cohort study of the apriori hypothesis that mortality from cardiovascu lar disease and all causes is associated with longterm

© 2012 RaaschouNielsen et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.