Air pollution and lung function in the European Community Respiratory Health Survey

BACKGROUND

The association of long-term air pollution and lung function has not been studied across adult European multi-national populations before. The aim of this study was to determine the association between long-term urban background air pollution and lung function levels, as well as change in lung function among European adults.

METHODS

Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and the ratio thereof (FEV1/FVC) were assessed at baseline and after 9 years of follow-up in adults from 21 European centres (followed-up sample 5610). Fine particles (PM(2.5)) were measured in 2000/2001 using central monitors.

RESULTS

Despite sufficient statistical power no significant associations were found between city-specific annual mean PM(2.5) and average lung function levels. The findings also do not support an effect on change in lung function, albeit statistical power was insufficient to significantly detect such an association.

CONCLUSIONS

The inability to refuse the null hypothesis may reflect (i) no effect of urban air pollution on lung function or (ii) inherent biases due to the study design. Examples of the latter are lack of individual-level air quality assignment, not quantified within-city contrasts in traffic-related pollution, or the heterogeneity of the studied populations and their urban environments. Future studies on long-term effects of air pollution on lung function could increase statistical power and reduce potential misclassification and confounding by characterizing exposure on the level of individuals, capturing contrasts due to local sources, in particular traffic.

Air Pollution and Inflammatory Response in Myocardial Infarction Survivors: Gene–Environment Interactions in a High-Risk Group

Ambient air pollution has been associated with an increased risk of hospital admission and mortality in potentially susceptible subpopulations, including myocardial infarction (MI) survivors. The multicenter epidemiological study described in this report was set up to study the role of air pollution in eliciting inflammation in MI survivors in six European cities, Helsinki, Stockholm, Augsburg, Rome, Barcelona, and Athens. Outcomes of interest are plasma concentrations of the proinflammatory cytokine interleukin 6 (IL-6) and the acute-phase proteins C-reactive protein (CRP) and fibrinogen. In addition, the study was designed to assess the role of candidate gene polymorphisms hypothesized to lead to a modification of the short-term effects of ambient air pollution. In total, 1003 MI survivors were recruited and assessed with at least 2 repeated clinic visits without any signs of infections. In total, 5813 blood samples were collected, equivalent to an average of 5.8 repeated clinic visits per subject (97% of the scheduled 6 repeated visits). Subjects across the six cities varied with respect to risk factor profiles. Most of the subjects were nonsmokers, but light smokers were included in Rome, Barcelona, and Athens. Substantial inter- and intraindividual variability was observed for IL-6 and CRP. The study will permit assessing the role of cardiovascular disease risk factors, including ambient air pollution and genetic polymorphisms in candidate genes, in determining the inter- and the intraindividual variability in plasma IL-6, CRP, and fibrinogen concentrations in MI survivors.

Air pollution and inflammation (interleukin-6, C-reactive protein, fibrinogen) in myocardial infarction survivors

BACKGROUND

Numerous studies have found that ambient air pollution has been associated with cardiovascular disease exacerbation.

OBJECTIVES

Given previous findings, we hypothesized that particulate air pollution might induce systemic inflammation in myocardial infarction (MI) survivors, contributing to an increased vulnerability to elevated concentrations of ambient particles.

METHODS

A prospective longitudinal study of 1,003 MI survivors was performed in six European cities between May 2003 and July 2004. We compared repeated measurements of interleukin 6 (IL-6), fibrinogen, and C-reactive protein (CRP) with concurrent levels of air pollution. We collected hourly data on particle number concentrations (PNC), mass concentrations of particulate matter (PM) < 10 microm (PM(10)) and < 2.5 microm (PM(2.5)), gaseous pollutants, and meteorologic data at central monitoring sites in each city. City-specific confounder models were built for each blood marker separately, adjusting for meteorology and time-varying and time-invariant covariates. Data were analyzed with mixed-effects models.

RESULTS

Pooled results show an increase in IL-6 when concentrations of PNC were elevated 12-17 hr before blood withdrawal [percent change of geometric mean, 2.7; 95% confidence interval (CI), 1.0-4.6]. Five day cumulative exposure to PM(10) was associated with increased fibrinogen concentrations (percent change of arithmetic mean, 0.6; 95% CI, 0.1-1.1). Results remained stable for smokers, diabetics, and patients with heart failure. No consistent associations were found for CRP.

CONCLUSIONS

Results indicate an immediate response to PNC on the IL-6 level, possibly leading to the production of acute-phase proteins, as seen in increased fibrinogen levels. This might provide a link between air pollution and adverse cardiac events.

Annoyance due to air pollution in Europe

BACKGROUND

Annoyance due to air pollution is a subjective score of air quality, which has been incorporated into the National Environmental monitoring of some countries. The objectives of this study are to describe the variations in annoyance due to air pollution in Europe and its individual and environmental determinants.

METHODS

This study took place in the context of the European Community Respiratory Health Survey II (ECRHS II) that was conducted during 1999-2001. It included 25 centres in 12 countries and 7867 randomly selected adults from the general population. Annoyance due to air pollution was self-reported on an 11-point scale. Annual mean mass concentration of fine particles (PM(2.5)) and its sulphur (S) content were measured in 21 centres as a surrogate of urban air pollution.

RESULTS

Forty-three per cent of participants reported moderate annoyance (1-5 on the scale) and 14% high annoyance (> or =6) with large differences across centres (2-40% of high annoyance). Participants in the Northern European countries reported less annoyance. Female gender, nocturnal dyspnoea, phlegm and rhinitis, self-reported car and heavy vehicle traffic in front of the home, high education, non-smoking and exposure to environmental tobacco smoke were associated with higher annoyance levels. At the centre level, adjusted means of annoyance scores were moderately associated with sulphur urban levels (slope 1.43 microg m(-3), standard error 0.40, r = 0.61).

CONCLUSIONS

Annoyance due to air pollution is frequent in Europe. Individuals' annoyance may be a useful measure of perceived ambient quality and could be considered a complementary tool for health surveillance.

Chronic bronchitis and urban air pollution in an international study

OBJECTIVES

The chronic effects of urban air pollution are not well known. The authors' aim was to investigate the association between the prevalence and new onset of chronic bronchitis and urban air pollution.

METHODS

Subjects from the general population randomly selected for the European Community Respiratory Health Survey (ECRHS I) during 1991-93 in 21 centres in 10 countries were followed up from the years 2000 to 2002 (n = 3232 males and 3592 females; average response rate = 65.3%). PM2.5 and elements, with the same equipment at centre level, and home outdoor NO2 in 1634 individuals were measured. Hierarchical models were used.

RESULTS

The prevalence and new onset of chronic phlegm during follow up were 6.9% and 4.5%, respectively, 5.3% in males and 3.5% in females. Smoking, rhinitis, poor education, and low social class were associated with (prevalence and new onset of) chronic phlegm in both genders, and occupational exposures in males and traffic intensity (adjusted odds ratio for constant traffic, OR = 1.86; 95% CI 1.24 to 2.77) as well as home outdoor NO2 (OR > 50 microg/m3v < 20 microg3 = 2.71; 95% CI 1.03 to 7.16) among females. PM2.5 and S content at centre level did not show any association with prevalence or new onset of chronic phlegm. Similar results were obtained with chronic productive cough.

CONCLUSION

Individual markers of traffic at household level such as reported intensity and outdoor NO2 were risk factors for chronic bronchitis among females.