Area under flow-volume loop may predict severe exacerbation in COPD patients with high grade of dyspnea

• Published in: Respiratory physiology & neurobiology 2021-12, Vol.294, p.103771-103771, Article 103771
• Main Authors: Satici, Celal, Demirkol, Mustafa Asim, Arpinar Yigitbas, Burcu, Erinc, Aysegül, Kosar, Ayse Filiz
• Format: Article
• Language: English
• Subjects: Aged; AreaFE; CAT score; COPD; Dyspnea - etiology; Dyspnea - physiopathology; Exacerbation; Female; Humans; Male; Middle Aged; Prognosis; Pulmonary Disease, Chronic Obstructive - complications; Pulmonary Disease, Chronic Obstructive - diagnosis; Pulmonary Disease, Chronic Obstructive - physiopathology; Retrospective Studies; Risk Factors; Severity of Illness Index; Spirometry; Symptom Flare Up
• ISSN: 1569-9048; 1878-1519
• DOI: 10.1016/j.resp.2021.103771

•AreaFE% was found to be more sensitive parameter than conventional spirometric parameters in the diagnosis of hyperinflation.•Hyperinflation is the main underlying mechanism of a COPD exacerbation.•Low AreaFE% value is an independent risk factor in addition to a high CAT score in predicting future severe exacerbation.•AreaFE% has an excellent discriminative ability in predicting future severe exacerbation. Exacerbations in patients with COPD may still be unpredictable, although the general risk factors have been well defined. We aimed to determine the role of a novel parameter, area under flow-volume loop, in predicting severe exacerbations. In this single-centre retrospective cohort study, 81 COPD patients over 40 years of age with high grade of dyspnea (having a CAT score of ≥10) and a history of ≥1 moderate exacerbation in the previous year were included. Area under flow-volume curve (AreaFE%) was obtained from pulmonary function test graph and calculated from Matlab programme. Univariate and multivariate logistic regression analyses were performed to determine independent risk factors of the severe exacerbation. Patients with severe exacerbation (n = 70, 86.4 %) were older. They had lower FEV1%, FVC%, 6MWD, AreaFE% and higher CAT score than patients without exacerbation. After performing multivariate analysis, high CAT score and low AreaFE% value were found to be independent risk factors for severe exacerbation (OR: 1.12, 95 % CI: 1.065–1.724; p = 0.01 and OR: 1.18, 95 % CI: 0.732−0.974; p = 0.02). We found that a low AreaFE% value was an independent risk factor in addition to a high CAT score and these both have an excellent discriminative ability in predicting the risk of severe exacerbation