The diagnostic importance of a reduced FEV1/FEV6

8Citations
Citations of this article
23Readers
Mendeley users who have this article in their library.

Abstract

Background: On spirometry the FEV1/FEV6 ratio has been advocated as a surrogate for the FEV1/FVC. The significance of isolated reductions in either the FEV1/FEV6 or FEV1/FVC is not known. Methods: First-time adult spirograms (n = 22,837), with concomitant lung volumes (n = 12,040), diffusion (n = 14,154), and inspiratory capacity (n = 12,480) were studied. Four groups were compared. 1) Only FEV1/FEV6 reduced (n = 302). 2) Only FEV1/FVC reduced (n = 1158). 3) Both ratios reduced (n = 6593). 4) Both ratios normal (n = 14,784). Results: In patients with obstructed spirometry (either a reduced FEV1/FVC and/or FEV1/FEV6), 3.8% only had a reduced FEV1/FEV6, while 14.4% only had a reduced FEV1/FVC. The mean FEV1 was lower when both ratios were reduced. The group with only a reduced FEV1/FEV6, compared to only the FEV1/FVC reduced, had a lower FEV1, FVC, BMI, Expiratory Time, and IC (p values < 0.0001). DLCO was also lower (p = 0.005), and the FEV1/FVC and RV/TLC were higher (p values < 0.0001). When the patients with only a reduced FEV1/FEV6 had a subsequent spirogram, 60% had a reduced FEV1/FVC when their mean expiratory times were 3.5 seconds longer. Ninety percent of this group had strong clinical evidence of airways obstruction. Conclusions: The FEV1/FEV6 is not as sensitive as the FEV1/FVC for diagnosing airways obstruction, but in the presence of a normal FEV1/FVC, subjects have greater physiologic abnormalities than when only the FEV1/FVC is reduced. The FEV1/FEV6 ratio should not replace the FEV1/FVC as the standard for airways obstruction, but there is benefit including this measurement to identify individuals with greater air trapping and diffusion abnormalities. © 2012 Informa Healthcare USA, Inc.

Cite

CITATION STYLE

APA

Morris, Z. Q., Huda, N., & Burke, R. R. (2012). The diagnostic importance of a reduced FEV1/FEV6. COPD: Journal of Chronic Obstructive Pulmonary Disease, 9(1), 22–28. https://doi.org/10.3109/15412555.2012.630701

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free