0
Clinical Investigations: ASTHMA |

Ratio Between Forced Expiratory Flow Between 25% and 75% of Vital Capacity and FVC Is a Determinant of Airway Reactivity and Sensitivity to Methacholine*

Annie Lin Parker; Muhanned Abu-Hijleh; F. Dennis McCool
Author and Funding Information

*From the Department of Pulmonary and Critical Care Medicine, Memorial Hospital of Rhode Island and Brown Medical School, Providence, RI.

Correspondence to: Annie Lin Parker, MD, FCCP, Department of Pulmonary and Critical Care Medicine, Memorial Hospital of Rhode Island, 111 Brewster St, Pawtucket, RI 02860; e-mail: Annie_Parker@brown.edu



Chest. 2003;124(1):63-69. doi:10.1378/chest.124.1.63
Text Size: A A A
Published online

Study objective: The ratio between forced expiratory flow between 25% and 75% of vital capacity (FEF25–75) and FVC is thought to reflect dysanapsis between airway size and lung size. A low FEF25–75/FVC ratio is associated with airway responsiveness to methacholine in middle-aged and older men. The current study was designed to assess this relationship in both male and female subjects over a broader range of ages.

Study design: Data analysis of consecutive subjects who had a ≥ 20% reduction in FEV1 after ≤ 189 cumulative units of methacholine over a 7-year period.

Setting: Pulmonary function laboratory in a university-affiliated hospital.

Patients: A total of 764 consecutive subjects aged 4 to 91 years (mean ± SD age, 40.8 ± 19.6 years). There were 223 male (29.3%) and 540 female (70.7%) subjects.

Measurements and results: Airway reactivity was assessed as the dose-response slope of the reduction in FEV1 from baseline vs the cumulative dose of inhaled methacholine. The cumulative dose of methacholine causing 20% reduction in FEV1 (PD20) was used as the indicator of airway sensitivity. In a linear regression model that included age, height, and percentage of predicted FEV1, the FEF25–75/FVC ratio accounted for 7.6% of variability in airway reactivity (p < 0.0001, r2 = 0.076). Subjects with higher airway sensitivity, indicated by lower PD20, also had a lower FEF25–75/FVC ratio.

Conclusions: A low FEF25–75/FVC ratio, indicating small airway size relative to lung size, is associated with higher airway sensitivity and reactivity to methacholine in susceptible subjects.

Figures in this Article

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
Guidelines
Diagnosis and management of asthma.
Institute for Clinical Systems Improvement
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543