0
Pulmonary Rehabilitation |

Using the Lower Limit of Normal (LLN) for the FEV1/FVC Ratio Changes the Prevalence of Airway Obstruction in a Hospital Based-Population

Vanina Martín, MD; Marcela Heres, MD; Sebastian Lamot, MD; Marco Solis, MD; Nicolas Itcovici, MD; Silvia Quadrelli, MD
Author and Funding Information

Fundación Sanatorio Guemes, Ciudad Autónoma de Buenos Aires, Argentina


Chest. 2013;144(4_MeetingAbstracts):826A. doi:10.1378/chest.1704136
Text Size: A A A
Published online

Abstract

SESSION TITLE: Physiology/PFTs/Rehabilitation Posters

SESSION TYPE: Original Investigation Poster

PRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PM

PURPOSE: Published guidelines recommend spirometry to accurately diagnose COPD. However, even spirometry-based COPD prevalence estimates can vary widely. GOLD recommendations define COPD as a post-bronchodilator FEV/FVC of <70%, with the severity based on the value of FEV1. However, there is currently no consensus on the criteria for diagnosing COPD. This study evaluated the impact of different definitions of airway obstruction on the estimated prevalence of obstruction in a hospital-based sample.

METHODS: All consecutive spirometry tests performed in adult subjects at the pulmonary function laboratory of a tertiary reference center from January 2011 to December 2012. Obstructive airway disease was defined using the following criteria: 1)self-reported diagnosis of chronic bronchitis or emphysema; 2)FEV1/FVC<0.70; 3)FEV1/FVC<0.70 and FEV1<80% predicted (GOLD Stage IIA); 4)FEV1/FVC<0.88 (ERS 95); 5) FEV1/FVC below the LLN (ECCS/ERS reference values). This analysis was performed using the ECCS/ERS prediction equation. All analyses were performed using SPSS 14.0 for Windows (SPSS, Chicago, Illinois, USA).

RESULTS: 3567 subjects that performed an eligible spirometry (1716 men, age 51,5±16,6 year-old, FVC 90,6±18,4%, FEV1 81,2±20,1%, FEV1/FVC 71,1±11,4%). Rates in studied patients varied from 1) 15,9 % (self-report), 2) 37,1% in GOLD fixed FEV1/FVC ratio below 70%, 3) 27,7% in GOLD stage II (FEV1/FVC<70% + FEV1<80%), 4) 69% (fixed ratio< 88% using ERS equation) and 5) 28% (FEV1/FVC below the LLN). For persons aged >50 yrs, the fixed ratio criteria produced the highest rate estimates. For all subgroups tested, the GOLD Stage II criteria produced lower estimates than other spirometry-based definitions.

CONCLUSIONS: This study demonstrates that in the daily practice of a pulmonary function laboratory, large differences in the prevalence of obstruction exist when defined by spirometry that arise from using different definitions even using the same prediction equations. While a fixed cut-off seems easy to apply, it comes at the expense of erroneous classification of disease.

CLINICAL IMPLICATIONS: A clear definition of COPD that can serve as a guide to clinicians is still not available.

DISCLOSURE: The following authors have nothing to disclose: Vanina Martín, Marcela Heres, Sebastian Lamot, Marco Solis, Nicolas Itcovici, Silvia Quadrelli

No Product/Research Disclosure Information


Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543