title: Bronchodilator response following methacholine-induced bronchoconstriction predicts acute asthma exacerbations.
abstract: Methacholine bronchial provocation test provides the concentration of methacholine causing a 20% decrease in forced expiratory volume in 1 s (FEV1) from baseline (PC20). The dose-response slope (DRS), and other continuous indices of responsiveness (CIR; the percentage decline from the post-diluent baseline FEV1 after the last dose of methacholine), and per cent recovery index (PRI; the percentage increase from the maximally reduced FEV1 after bronchodilator inhalation) are alternative measures. The clinical relevance of these indices in predicting acute asthma exacerbations has not been fully evaluated.In two prospective cohorts of childhood and elderly asthmatics, baseline PC20, DRS, CIR and PRI were measured and evaluated as predictors of acute asthma exacerbations.We found that PRI was significantly related to the presence of asthma exacerbations during the first year of follow-up in both cohorts of childhood (p=0.025) and elderly asthmatics (p=0.003). In addition, PRI showed a significant association with the total number of steroid bursts during 4.3 years of follow-up in the cohort of childhood asthmatics (p=0.04).We demonstrated that PRI, an index of reversibility following methacholine-induced bronchoconstriction, was a good clinical predictor of acute exacerbations of asthma in both childhood and elderly asthmatics.
authors.affiliation: The Channing Division of Network Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Dept of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea guinea71@snu.ac.kr.
authors.forename: Heung-Woo
authors.identifier: 0000-0002-4630-9922
authors.initials: HW
authors.lastname: Park
authors.affiliation: Dept of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Woo-Jung
authors.initials: WJ
authors.lastname: Song
authors.affiliation: Dept of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Yoon-Suk
authors.initials: YS
authors.lastname: Chang
authors.affiliation: Dept of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang-Heon
authors.initials: SH
authors.lastname: Cho
authors.affiliation: The Channing Division of Network Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Soma
authors.initials: S
authors.lastname: Datta
authors.affiliation: The Channing Division of Network Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Partners Center for Personalized Medicine, Partners Health Care, Boston, MA, USA.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Weiss
authors.affiliation: The Channing Division of Network Medicine, Dept of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Kelan G
authors.initials: KG
authors.lastname: Tantisira
mesh_terms: D000280:Administration, Inhalation; D000368:Aged; D001249:Asthma / Q000188:drug therapy*; D001900:Boston; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000187:drug effects*; D016085:Bronchoconstrictor Agents / Q000494:pharmacology*; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D002648:Child; D018450:Disease Progression; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D016015:Logistic Models; D008297:Male; D016210:Methacholine Chloride / Q000494:pharmacology*; D011446:Prospective Studies; D056910:Republic of Korea
chemical_list: D016085:Bronchoconstrictor Agents; D001993:Bronchodilator Agents; D016210:Methacholine Chloride