title: Maximal mid-expiratory flow is a surrogate marker of lung clearance index for assessment of adults with bronchiectasis.
abstract: Little is known about the comparative diagnostic value of lung clearance index (LCI) and maximal mid-expiratory flow (MMEF) in bronchiectasis. We compared the diagnostic performance, correlation and concordance with clinical variables, and changes of LCI and MMEF% predicted during bronchiectasis exacerbations (BEs). Patients with stable bronchiectasis underwent history inquiry, chest high-resolution computed tomography (HRCT), multiple-breath nitrogen wash-out test, spirometry and sputum culture. Patients who experienced BEs underwent these measurements during onset of BEs and 1 week following antibiotics therapy. Sensitivity analyses were performed in mild, moderate and severe bronchiectasis. We recruited 110 bronchiectasis patients between March 2014 and September 2015. LCI demonstrated similar diagnostic value with MMEF% predicted in discriminating moderate-to-severe from mild bronchiectasis. LCI negatively correlated with MMEF% predicted. Both parameters had similar concordance in reflecting clinical characteristics of bronchiectasis and correlated significantly with forced expiratory flow in one second, age, HRCT score, Pseudomonas aeruginosa colonization, cystic bronchiectasis, ventilation heterogeneity and bilateral bronchiectasis. In exacerbation cohort (n = 22), changes in LCI and MMEF% predicted were equally minimal during BEs and following antibiotics therapy. In sensitivity analyses, both parameters had similar diagnostic value and correlation with clinical variables. MMEF% predicted is a surrogate of LCI for assessing bronchiectasis severity.
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Wei-Jie
authors.initials: WJ
authors.lastname: Guan
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Yuan
authors.affiliation: Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Li
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Rong-Chang
authors.initials: RC
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
authors.forename: Nan-Shan
authors.initials: NS
authors.lastname: Zhong
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism*; D001987:Bronchiectasis / Q000378:metabolism* / Q000382:microbiology / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000378:metabolism / Q000382:microbiology / Q000503:physiopathology; D045853:Exhalation / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008168:Lung / Q000378:metabolism / Q000382:microbiology / Q000503:physiopathology*; D008297:Male; D011550:Pseudomonas aeruginosa / Q000472:pathogenicity; D013147:Spirometry / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D015415:Biomarkers