Maximal mid-expiratory flow detects early lung disease in α1-antitrypsin deficiency

James Stockley, Asem M. Ismail, Siân M Hughes, Ross Edgar, Robert A Stockley, Elizabeth Sapey*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

45 Citations (Scopus)
210 Downloads (Pure)

Abstract

Pathological studies suggest that loss of small airways precedes airflow obstruction and emphysema in chronic obstructive pulmonary disease (COPD). Not all α1-antitrypsin deficiency (AATD) patients develop COPD, and measures of small airways function might be able to detect those at risk. Maximal mid-expiratory flow (MMEF), forced expiratory volume in 1 s (FEV1), ratio of FEV1/forced vital capacity (FVC), health status, presence of emphysema (computed tomography (CT) densitometry) and subsequent decline in FEV1 were assessed in 196 AATD patients. FEV1/FVC, FEV1 % predicted and lung densitometry related to MMEF % pred (r2=0.778, p<0.0001; r2=0.787, p<0.0001; r2=0.594, p<0.0001, respectively) in a curvilinear fashion. Patients could be divided into those with normal FEV1/FVC and MMEF (group 1), normal FEV1/FVC and reduced MMEF (group 2) and those with spirometrically defined COPD (group 3). Patients in group 2 had worse health status than group 1 (median total St George’s Respiratory Questionnaire (SGRQ) 23.15 (interquartile range (IQR) 7.09–39.63) versus 9.67 (IQR 1.83–22.35); p=0.006) and had a greater subsequent decline in FEV1 (median change in FEV1 −1.09% pred per year (IQR −1.91–0.04% pred per year) versus −0.04% pred per year (IQR −0.67–0.03% pred per year); p=0.007). A reduction in MMEF is an early feature of lung disease in AATD and is associated with impaired health status and a faster decline in FEV1.

Original languageEnglish
Article number1602055
JournalThe European respiratory journal
Volume49
Issue number3
DOIs
Publication statusPublished - 1 Mar 2017

Bibliographical note

Funding Information:
The authors would like to thank patients with AATD for taking part in this study, Diane Griffiths (Registered Nurse, University Hospital Birmingham NHS Foundation Trust, Birmingham, UK), Anita Pye (Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK) and Rebecca Bray (ADAPT Patient Coordinator, University Hospital Birmingham NHS Foundation Trust, Birmingham, UK) for assistance with patient recruitment, and the Alpha-1 Foundation and CSL Behring for funding this work.

Publisher Copyright:
Copyright ©ERS 2017.

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine

Fingerprint

Dive into the research topics of 'Maximal mid-expiratory flow detects early lung disease in α1-antitrypsin deficiency'. Together they form a unique fingerprint.

Cite this