ArticleBMC pulmonary medicine2022
Relationship between concavity of the flow-volume loop and small airway measures in smokers with normal spirometry.
Article in BMC pulmonary medicine, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
What it found
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Who cites it
9 citing papers in PubMed, 10 citations in OpenAlex.
- Morphological Analysis of the Flow-Volume Curve for Identifying Fixed Airflow Obstruction: A Scoping Review.Advances in respiratory medicine · 2026Article
- It's not all about small airways disease: key limitations of oscillometry interpretation.Frontiers in allergy · 2026Review
- Concavity of the maximal expiratory flow-volume curve, and incidence of COPD and respiratory symptoms: a population-based cohort study.ERJ open research · 2026Article
- TBMJ open respiratory research · 2025Article
- Article
- Machine learning approach to flare-up detection and clustering in chronic obstructive pulmonary disease (COPD) patients.Health information science and systems · 2024Article
- Systems Engineering Approach to Modeling and Analysis of Chronic Obstructive Pulmonary Disease Part II: Extension for Variable Metabolic Rates.ACS omega · 2024Article
- Development and evaluation of a computerized algorithm for the interpretation of pulmonary function tests.PloS one · 2024Article
- Systems Engineering Approach to Modeling and Analysis of Chronic Obstructive Pulmonary Disease.ACS omega · 2023Article
Corrections and comments
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Authors and funding
7 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThere is increasing evidence of small airway abnormalities in smokers despite normal spirometry. The concavity in the descending limb of the maximum expiratory flow curve (MEFV) is a recognised feature of obstruction and can provide information beyond FEV
methodsEighty smokers with normal spirometry had small airway function assessed: multiple breath nitrogen washout (MBNW) from which ventilation heterogeneity in the diffusion-dependent acinar (Sacin) and convection-dependent conductive (Scond) airways were assessed, and impulse oscillometry system (IOS) from which respiratory resistance and reactance at 5 Hz (R5 and X5) were measured. Concavity measures were calculated from the MEFV, partitioned into global and peripheral concavity.
resultsWe found abnormal peripheral and global concavity as well as acinar ventilation heterogeneity are common in "normal" smokers. Concavity measures were not related to either MBNW or IOS measurements.
conclusionAbnormalities in concavity indices and MBNW or oscillometry parameters are common in smokers despite normal spirometry. However, these measures likely reflect different mechanisms of peripheral airway dysfunction.
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