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An Efficient Diagnosis of Diffuse Parenchymal Lung Disease from Spirometry Exploring the Novel Role of FEF25–75
CC BY-NC-ND 4.0 · Indian J Med Paediatr Oncol 2022; 43(S 01): S1-S19
DOI: DOI: 10.1055/s-0042-1755481
Correspondence to: parthachest@yahoo.com
Background: The peripheral interstitial involvement in diffuse parenchymal lung disease (DPLD) can affect the small airways and, thus influence the FEF25–75 (forced expiratory flow), a marker of small airway function in spirometry. Here we evaluate the role of FEF25–75 for the diagnosis of DPLD that is otherwise diagnosed by high-resolution computerized tomography of chest.
Materials and Methods: FVC (forced vital capacity), FEF25–75, FEV1 (forced expiratory volume), and derived variables (FVC/FEF25–75) are used to differentiate DPLD from normal, obstructive lung disease (OLD) populations. Using different combinations of variables, receiver operating characteristic curve and regression analysis are done to identify the best possible combination to diagnose DPLD from spirometry.
Results: We included 639 adult patients’ (normal = 64, DPLD = 268, and OLD = 307 including asthma = 153 and COPD = 154) spirometry data. FEF25–75 alone could differentiate unmixed DPLD from OLD with sensitivity and specificity of 86.9 and 85.1%, respectively. The derived variables also showed promising diagnostic accuracies. A regression equation using age, FVC, FEV1/FVC, and FVC/FEF25–75(%) is found to have 79% diagnostic accuracy of DPLD on test population (n = 639). The same equation showed 90 and 87% diagnostic accuracy of DPLD in validation population of 427 mixed patients from same center and 100 mixed patients from different centers.
Conclusion: The inclusion of derived variables from spirometry and the regression equation using age, FVC, FEV1/FVC, FVC/FEF25–75 (%) appears rewarding in the diagnostic exercise for DPLD. Hence, this spirometric approach needs further validation from multiple centers to be included in clinical practice.
Publication History
Article published online:
22 August 2022
© 2022. Indian Society of Medical and Paediatric Oncology. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India
Correspondence to: parthachest@yahoo.com
Background: The peripheral interstitial involvement in diffuse parenchymal lung disease (DPLD) can affect the small airways and, thus influence the FEF25–75 (forced expiratory flow), a marker of small airway function in spirometry. Here we evaluate the role of FEF25–75 for the diagnosis of DPLD that is otherwise diagnosed by high-resolution computerized tomography of chest.
Materials and Methods: FVC (forced vital capacity), FEF25–75, FEV1 (forced expiratory volume), and derived variables (FVC/FEF25–75) are used to differentiate DPLD from normal, obstructive lung disease (OLD) populations. Using different combinations of variables, receiver operating characteristic curve and regression analysis are done to identify the best possible combination to diagnose DPLD from spirometry.
Results: We included 639 adult patients’ (normal = 64, DPLD = 268, and OLD = 307 including asthma = 153 and COPD = 154) spirometry data. FEF25–75 alone could differentiate unmixed DPLD from OLD with sensitivity and specificity of 86.9 and 85.1%, respectively. The derived variables also showed promising diagnostic accuracies. A regression equation using age, FVC, FEV1/FVC, and FVC/FEF25–75(%) is found to have 79% diagnostic accuracy of DPLD on test population (n = 639). The same equation showed 90 and 87% diagnostic accuracy of DPLD in validation population of 427 mixed patients from same center and 100 mixed patients from different centers.
Conclusion: The inclusion of derived variables from spirometry and the regression equation using age, FVC, FEV1/FVC, FVC/FEF25–75 (%) appears rewarding in the diagnostic exercise for DPLD. Hence, this spirometric approach needs further validation from multiple centers to be included in clinical practice.
No conflict of interest has been declared by the author(s).
Publication History
Article published online:
22 August 2022
© 2022. Indian Society of Medical and Paediatric Oncology. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India