Back to Journals » International Journal of Chronic Obstructive Pulmonary Disease » Volume 10 » Issue 1

A new approach to assess COPD by identifying lung function break-points

Authors Eriksson G, Jarenbäck L, Peterson S, Ankerst J, Bjermer L, Tufvesson E

Received 3 April 2015

Accepted for publication 25 May 2015

Published 14 October 2015 Volume 2015:10(1) Pages 2193—2202


Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 3

Editor who approved publication: Dr Richard Russell

Göran Eriksson,1,* Linnea Jarenbäck,1,* Stefan Peterson,2 Jaro Ankerst,1 Leif Bjermer,1 Ellen Tufvesson1

1Respiratory Medicine and Allergology, Department of Clinical Sciences, Lund University, 2Regional Cancer Center South, Skåne University Hospital, Lund, Sweden

*These authors contributed equally to this work

Purpose: COPD is a progressive disease, which can take different routes, leading to great heterogeneity. The aim of the post-hoc analysis reported here was to perform continuous analyses of advanced lung function measurements, using linear and nonlinear regressions.
Patients and methods: Fifty-one COPD patients with mild to very severe disease (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I–IV) and 41 healthy smokers were investigated post-bronchodilation by flow-volume spirometry, body plethysmography, diffusion capacity testing, and impulse oscillometry. The relationship between COPD severity, based on forced expiratory volume in 1 second (FEV1), and different lung function parameters was analyzed by flexible nonparametric method, linear regression, and segmented linear regression with break-points.
Results: Most lung function parameters were nonlinear in relation to spirometric severity. Parameters related to volume (residual volume, functional residual capacity, total lung capacity, diffusion capacity [diffusion capacity of the lung for carbon monoxide], diffusion capacity of the lung for carbon monoxide/alveolar volume) and reactance (reactance area and reactance at 5Hz) were segmented with break-points at 60%–70% of FEV1. FEV1/forced vital capacity (FVC) and resonance frequency had break-points around 80% of FEV1, while many resistance parameters had break-points below 40%. The slopes in percent predicted differed; resistance at 5 Hz minus resistance at 20 Hz had a linear slope change of -5.3 per unit FEV1, while residual volume had no slope change above and -3.3 change per unit FEV1 below its break-point of 61%.
Conclusion: Continuous analyses of different lung function parameters over the spirometric COPD severity range gave valuable information additional to categorical analyses. Parameters related to volume, diffusion capacity, and reactance showed break-points around 65% of FEV1, indicating that air trapping starts to dominate in moderate COPD (FEV1 =50%–80%). This may have an impact on the patient’s management plan and selection of patients and/or outcomes in clinical research.

Keywords: spirometry, severity, body plethysmography, single-breath carbon-monoxide diffusion test, impulse oscillometry, break-point

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]


Other article by this author:

The effect of COPD severity and study duration on exacerbation outcome in randomized controlled trials

Eriksson G, Calverley PM, Jenkins CR, Anzueto AR, Make BJ, Lindberg M, Fagerås M, Postma DS

International Journal of Chronic Obstructive Pulmonary Disease 2017, 12:1457-1468

Published Date: 15 May 2017

Readers of this article also read:

COPD in Taiwan: a National Epidemiology Survey

Cheng SL, Chan MC, Wang CC, Lin CH, Wang HC, Hsu JY, Hang LW, Chang CJ, Perng DW, Yu CJ

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2459-2467

Published Date: 11 November 2015

Increased serum TRAIL and DR5 levels correlated with lung function and inflammation in stable COPD patients

Wu YQ, Shen YC, Zhang JL, Wan C, Wang T, Xu D, Yang T, Wen FQ

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2405-2412

Published Date: 6 November 2015

Prevalence of chronic obstructive pulmonary disease in asymptomatic smokers

Sansores RH, Velázquez-Uncal M, Pérez-Bautista O, Villalba-Caloca J, Falfán-Valencia R, Ramírez-Venegas A

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2357-2363

Published Date: 2 November 2015

Effect of tiotropium on lung function decline in early-stage of chronic obstructive pulmonary disease patients: propensity score-matched analysis of real-world data

Lee HY, Choi SM, Lee J, Park YS, Lee CH, Kim DK, Lee SM, Yoon HI, Yim JJ, Kim YW, Han SK, Yoo CG

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2185-2192

Published Date: 13 October 2015

Biomarker-based detection of asthma–COPD overlap syndrome in COPD populations

Tamada T, Sugiura H, Takahashi T, Matsunaga K, Kimura K, Katsumata U, Takekoshi D, Kikuchi T, Ohta K, Ichinose M

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2169-2176

Published Date: 9 October 2015

Prevalence and risk factors for COPD in greenhouse farmers: a large, cross-sectional survey of 5,880 farmers from northeast China

Liu S, Ren YG, Wen DL, Chen Y, Chen DH, Li LY, Zhang XH, Zhang YB, Fu S, Li ZH, Xia SY, Wang DL, Chen H, Zhao J, Wang XG

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:2097-2108

Published Date: 1 October 2015

Association between vitamin D receptor polymorphisms and osteoporosis in patients with COPD

Kim SW, Lee JM, Ha JH, Kang HH, Rhee CK, Kim JW, Moon HS, Baek KH, Lee SH

International Journal of Chronic Obstructive Pulmonary Disease 2015, 10:1809-1817

Published Date: 4 September 2015