TY - JOUR T1 - Computed tomography total airway count predicts progression to COPD in at risk smokers JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00307-2021 SP - 00307-2021 AU - Miranda Kirby AU - Benjamin M. Smith AU - Naoya Tanabe AU - James C. Hogg AU - Harvey O. Coxson AU - Don D. Sin AU - Jean Bourbeau AU - Wan C. Tan A2 - , Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/early/2021/07/15/23120541.00307-2021.abstract N2 - There is limited understanding of how to identify people at high risk of developing chronic obstructive pulmonary disease (COPD). Our objective was to investigate the association between computed tomography (CT) total airway count (TAC) and incident COPD over 3-years among ever-smokers from the population-based Canadian Cohort Obstructive Lung Disease (CanCOLD) study.CT and spirometry were acquired in ever-smokers at baseline; spirometry was repeated at 3-year follow-up. CT TAC was generated by summing all airway segments in the segmented airway tree (VIDA Diagnostics, Inc.). CT airway wall area, wall thickness for a theoretical airway with 10 mm perimeter (Pi10), and low attenuation areas below −856HU (LAA856) were also measured. Logistic and mixed effects regression models were constructed to determine the association for CT measurements with development of COPD and FEV1/FVC decline, respectively.Among 316 at risk participants evaluated at baseline (65±9 years, 40% female, 18±19 pack-years), incident COPD was detected in 56 participants (18%) over a median 3.1±0.6 years of follow-up. Among CT measurements, only TAC was associated with incident COPD (p=0.03), where a 1-sd decrement in TAC increased the odds ratio for incident COPD by a factor of two. In a multivariable linear regression model, reduced TAC was significantly associated with greater longitudinal FEV1/FVC decline (p=0.03), but no other measurements were significant.CT TAC predicts incident COPD in at risk smokers, indicating that smokers exhibit early structural changes associated with COPD prior to abnormal spirometry.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. 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 ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. Kirby reports other from VIDA Diagnostics Inc., outside the submitted work.Conflict of interest: Dr. Smith reports grants from the Canadian Institutes of Health Research, the National Institutes of Health (USA), the McGill Inter-disciplinary Initiative in Infection and Immunity (MI4), the Research Institute of the McGill University Health Centre, the Quebec Lung Association, and the Quebec Health Research Fund outside the submitted work.Conflict of interest: Dr. Tanabe reports grants from FUJIFILM, personal fees from AstraZeneka, personal fees from Boehringer Ingelheim, personal fees from GlaxoSmithKline, outside the submitted work.Conflict of interest: Dr. Hogg has nothing to disclose.Conflict of interest: Dr. Coxson has nothing to disclose.Conflict of interest: Dr. Sin reports personal fees from AstraZeneca, personal fees from Boehringer Ingelheim, personal fees from Grifols, outside the submitted work.Conflict of interest: Dr. Bourbeau reports grants from CIHR, grants from Canadian Respiratory Research Network (CRRN), personal fees from Canadian Thoracic Society, personal fees from CHEST, grants from Foundation of the MUHC, grants from Aerocrine, grants and personal fees from AstraZeneca, grants and personal fees from Boehringer Ingelheim, grants and personal fees from Grifols, grants and personal fees from GlaxoSmithKline, grants and personal fees from Novartis, grants and personal fees from Trudell, outside the submitted work.Conflict of interest: Dr. Tan reports grants from Canadian Institute of Heath Research (CIHR/Rx&D Collaborative Research Program Operating Grants- 93326) with industry partners Astra Zeneca Canada Ltd., Boehringer-Ingelheim Canada Ltd, GlaxoSmithKline Canada Ltd, Merck, Novartis Pharma Canada Inc., Nycomed Canada Inc., Pfizer Canada Ltd., during the conduct of the study; personal fees from GlaxoSmith Kline, Canada, personal fees from Astrazeneca, Canada, outside the submitted work. ER -