Abstract
The role of air pollution in chronic obstructive pulmonary disease (COPD) remains uncertain.
The aim was to assess the impact of chronic exposure to air pollution on COPD in four cohorts using the standardised ESCAPE exposure estimates. Annual average particulate matter (PM), nitrogen oxides (NOx) and road traffic exposure were assigned to home addresses using land-use regression models. COPD was defined by NHANES reference equation (forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) less than the lower limit of normal) and the Global Initiative for Chronic Obstructive Lung Disease criterion (FEV1/FVC <0.70) and categorised by severity in non-asthmatics.
We included 6550 subjects with assigned NOx and 3692 with PM measures. COPD was not associated with NO2 or PM10 in any individual cohort. In meta-analyses only NO2, NOx, PM10 and the traffic indicators were positively, although not significantly, associated with COPD. The only statistically significant associations were seen in females (COPD prevalence using GOLD: OR 1.57, 95% CI 1.11–2.23; and incidence: OR 1.79, 95% CI 1.21–2.68).
None of the principal results were statistically significant, the weak positive associations of exposure with COPD and the significant subgroup findings need to be evaluated in further well standardised cohorts followed up for longer time, and with time-matched exposure assignments.
Abstract
Results from the ESCAPE study: what is the association of COPD prevalence and incidence with ambient air pollution? http://ow.ly/rQcFM
Footnotes
For editorial comments see page 558.
This article has supplementary material available from erj.ersjournals.com
Support statement: ESCAPE funding: the research leading to these results has received funding from the European Community's Seventh Framework Program (FP7/2007-2011) under grant agreement number 211250. This research would not have been possible without the large previous investments into the original cohort studies contributing existing data to ESCAPE. For further details of these, please refer to the acknowledgements section.
Conflict of interest: Disclosures can be found alongside the online version of this article at erj.ersjournals.com
- Received July 31, 2013.
- Accepted December 10, 2013.
- ©ERS 2014