Impact of air pollution on lung function in cystic fibrosis over a decade in London: a UK CF Registry study
File(s)
Article in press
Author(s)
Saleem Khan, Muhammad
Barratt, Benjamin
Davies, Bethan
Simmonds, Nicholas
Piel, Fred
Type
Journal Article
Abstract
Objective: Despite extensive research on the detrimental effects of air pollution on respiratory diseases like asthma and chronic obstructive pulmonary disease (COPD), the
impact on people with cystic fibrosis remains understudied. Our study aimed to quantify the
association between air pollution exposure and lung function decline in people with CF in
London, United Kingdom (UK).
Methods: Using ten years (2008-2017) of UK Cystic Fibrosis Registry data, we conducted a longitudinal cohort study to evaluate the association between air pollution and the rate of decline in percent predicted forced expiratory volume in one second (ppFEV1) among people with CF. Residential postcode exposure was based on high-resolution models of particulate matter with a diameter of less than 2.5 micrometres (PM2.5) and nitrogen dioxide (NO2) from the London Air Pollution Toolkit. We estimated the temporal decline in ppFEV1 in high, medium and low exposure sub-groups based on air pollutant concentration tertiles using linear mixed models with random intercepts.
Results: We used 3,333 ppFEV1 measurements of 393 people with CF (122 children, 271 adults). Over 40% of these people with CF lived in postcodes falling into the most deprived national quintile. For PM2.5, the adjusted mean ppFEV1 declined by 13.3% (95%CI: -24.1; -4.0) over the study period in the high-exposure tertile compared to 8.5% (95%CI: -11.7; -6.4) in the low-exposure tertile. Differences between the exposure groups were less consistent for NO2. Children and people with CF with severe genotypes seemed particularly vulnerable.
Conclusions: This study provides novel evidence of the detrimental impact of air pollution on lung function in people with CF. Our findings highlight the importance of addressing air pollution as a modifiable risk factor to improve long-term outcomes of people with CF, and the need for national studies of the impact of environmental factors on CF in the UK.
impact on people with cystic fibrosis remains understudied. Our study aimed to quantify the
association between air pollution exposure and lung function decline in people with CF in
London, United Kingdom (UK).
Methods: Using ten years (2008-2017) of UK Cystic Fibrosis Registry data, we conducted a longitudinal cohort study to evaluate the association between air pollution and the rate of decline in percent predicted forced expiratory volume in one second (ppFEV1) among people with CF. Residential postcode exposure was based on high-resolution models of particulate matter with a diameter of less than 2.5 micrometres (PM2.5) and nitrogen dioxide (NO2) from the London Air Pollution Toolkit. We estimated the temporal decline in ppFEV1 in high, medium and low exposure sub-groups based on air pollutant concentration tertiles using linear mixed models with random intercepts.
Results: We used 3,333 ppFEV1 measurements of 393 people with CF (122 children, 271 adults). Over 40% of these people with CF lived in postcodes falling into the most deprived national quintile. For PM2.5, the adjusted mean ppFEV1 declined by 13.3% (95%CI: -24.1; -4.0) over the study period in the high-exposure tertile compared to 8.5% (95%CI: -11.7; -6.4) in the low-exposure tertile. Differences between the exposure groups were less consistent for NO2. Children and people with CF with severe genotypes seemed particularly vulnerable.
Conclusions: This study provides novel evidence of the detrimental impact of air pollution on lung function in people with CF. Our findings highlight the importance of addressing air pollution as a modifiable risk factor to improve long-term outcomes of people with CF, and the need for national studies of the impact of environmental factors on CF in the UK.
Date Issued
2026-02-05
Date Acceptance
2026-01-12
Citation
Thorax, 2026, pp.1-8
ISSN
0040-6376
Publisher
BMJ Publishing Group
Start Page
1
End Page
8
Journal / Book Title
Thorax
Copyright Statement
© Author(s) (or their employer(s)) 2026. Re- use permitted under CC BY. Published by BMJ Group.
License URL
Identifier
10.1136/thorax-2024-222710
Publication Status
Published online
Date Publish Online
2026-02-05