@article {Goeminne1702557, author = {C. Pieter Goeminne and Bianca Cox and Simon Finch and Michael R. Loebinger and Pallavi Bedi and Adam T Hill and Tom C Fardon and Kees de Hoogh and Tim S. Nawrot and James D. Chalmers}, title = {The impact of acute air pollution fluctuations on bronchiectasis pulmonary exacerbation. A case-crossover analysis}, elocation-id = {1702557}, year = {2018}, doi = {10.1183/13993003.02557-2017}, publisher = {European Respiratory Society}, abstract = {In bronchiectasis, exacerbations are believed to be triggered by infectious agents, but often no pathogen can be identified. We hypothesized that acute air pollution exposure may be associated with bronchiectasis exacerbations.We combined a case-crossover design with distributed lag models in an observational record linkage study. Patients were recruited from a specialist bronchiectasis clinic at Ninewells Hospital, Dundee, UK.We recruited 432 patients with HRCT diagnosed and clinically confirmed bronchiectasis. After excluding days with missing air pollution data, the final model for PM10 was based on 6741 exacerbations from 430 patients and for NO2 it included 6248 exacerbations from 426 patients. For each 10 {\textmu}g/m3 increase in PM10 and NO2, the risk of having an exacerbation that same day increased significantly by 4.5\% (95\%CI:0.9{\textendash}8.3) and 3.2\% (95\%CI:0.7{\textendash}5.8) respectively. The overall increase in risk of exacerbation for a 10 μg/m3 increase in air pollutant concentration was 11.2\% (95\%CI:6.0{\textendash}16.8) for PM10 and 4.7\% (95\%CI:0.1{\textendash}9.5) for NO2. Subanalysis showed significant higher relative risks during spring (PM10 1.198, 95\%CI 1.102{\textendash}1.303;NO2 1.146, 95\%CI:1.035{\textendash}1.268) and summer (PM10 2.142, 95\%CI:1.785{\textendash}2.570;NO2 1.352, 95\%CI:1.140{\textendash}1.602) when outdoor air pollution exposure would be expected to be highest.In conclusion, acute air pollution fluctuations are associated with increased exacerbation risk in bronchiectasis.Acute air pollution fluctuations are associated with increased exacerbation risk in patients with bronchiectasisFootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. Cox has nothing to disclose.Conflict of interest: Dr. Finch has nothing to disclose.Conflict of interest: Dr. Loebinger has nothing to disclose.Conflict of interest: Dr. Bedi has nothing to disclose.Conflict of interest: Prof. Hill reports personal fees from Bayer, outside the submitted work.Conflict of interest: Dr. Fardon has nothing to disclose.Conflict of interest: Dr. de Hoogh has nothing to disclose.Conflict of interest: Dr. Nawrot has nothing to disclose.Conflict of interest: Dr. Chalmers reports grants from Glaxosmithkline, grants and personal fees from Boehringer-Ingelheim, grants and personal fees from Pfizer, grants and personal fees from Astrazeneca, grants and personal fees from Bayer Healthcare, personal fees from Griffols, personal fees from Chiesi, outside the submitted work; .Conflict of interest: Dr. Goeminne reports personal fees from AstraZeneca, personal fees and non-financial support from Chiesi, personal fees and non-financial support from Boehringer, non-financial support from Pfizer, personal fees and non-financial support from Bayer, outside the submitted work; .}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/early/2018/05/24/13993003.02557-2017}, eprint = {https://erj.ersjournals.com/content/early/2018/05/24/13993003.02557-2017.full.pdf}, journal = {European Respiratory Journal} }