Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Jun 13;8(6):e65177.
doi: 10.1371/journal.pone.0065177. Print 2013.

Computed tomography structural lung changes in discordant airflow limitation

Affiliations

Computed tomography structural lung changes in discordant airflow limitation

Firdaus A A Mohamed Hoesein et al. PLoS One. .

Abstract

Background: There is increasing evidence that structural lung changes may be present before the occurrence of airflow limitation as assessed by spirometry. This study investigated the prevalence of computed tomography (CT) quantified emphysema, airway wall thickening and gas trapping according to classification of airflow limitation (FEV1/FVC <70% and/or < the lower limit of normal (LLN)) in (heavy) smokers.

Methods: A total number of 1,140 male former and current smokers participating in a lung cancer screenings trial (NELSON) were included and underwent chest CT scanning and spirometry. Emphysema was quantified by the 15(th) percentile, air way wall thickening by the square root of wall area for a theoretical airway with 10mm lumen perimeter (Pi10) and gas trapping by the mean lung density expiratory/inspiratory (E/I)-ratio. Participants were classified by entry FEV1/FVC: group 1>70%; group 2<70% but >LLN; and group 3<LLN. 32 restricted subjects, i.e. FEV1/FVC >70% but FEV1 <80% predicted, were excluded. Multivariate regression analysis correcting for covariates was used to asses the extent of emphysema, airway wall thickening and gas trapping according to three groups of airflow limitation.

Results: Mean (standard deviation) age was 62.5 (5.2) years and packyears smoked was 41.0 (18.0). Group 2 subjects when compared to group 1 had a significantly lower 15(th) percentile, -920.6 HU versus -912.2 HU; a higher Pi10, 2.87 mm versus 2.57 mm; and a higher E/I-ratio, 88.6% versus 85.6% (all p<0.001).

Conclusion: Subjects with an FEV1/FVC<70%, but above the LLN, have a significant greater degree of structural lung changes on CT compared to subjects without airflow limitation.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: HK is member of the medical advisory board of Roche Diagnostics. Siemens Germany and Roche Diagnostics provided funding towards this study. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials.

Similar articles

Cited by

References

    1. Mannino DM, Buist AS (2007) Global burden of COPD: risk factors, prevalence, and future trends. Lancet 370(9589): 765–73. - PubMed
    1. Jordan RE, Lam KH, Cheng KK, Miller MR, Marsh JL, et al. (2010) Case finding for chronic obstructive pulmonary disease: a model for optimising a targeted approach. Thorax 65(6): 492–8. - PMC - PubMed
    1. Vestbo J, Hurd SS, Agusti AG, Jones PW, Vogelmeier C, et al... (2012) Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease, GOLD Executive Summary. Am J Respir Crit Care Med Epub ahead of print. doi: 10.1164/rccm.201204–0596. - PubMed
    1. Hogg JC (2004) Pathophysiology of airflow limitation in chronic obstructive pulmonary disease. Lancet 364(9435): 709–21. - PubMed
    1. Hackx M, Bankier AA, Gevenois PA (2012) Chronic Obstructive Pulmonary Disease: CT Quantification of Airways Disease. Radiology 265(1): 34–48. - PubMed

Publication types

MeSH terms

Grants and funding

Funding was provided by European Union (EU) Framework Package Seven (FP7), grant number 201379, COPACETIC. The NELSON-trial was sponsored by: Netherlands Organisation for Health Research and Development (ZonMw); Dutch Cancer Society Koningin Wilhelmina Fonds (KWF); Stichting Centraal Fonds Reserves van Voormalig Vrijwillige Ziekenfondsverzekeringen (RvvZ); Siemens Germany; Roche Diagnostics; Rotterdam Oncologic Thoracic Steering committee (ROTS); and G.Ph.Verhagen Trust, Flemish League Against Cancer, Foundation Against Cancer and Erasmus Trust Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.