title: Reversibility of the pulmonary function based on the partial flow-volume curve predicts the efficacy of bronchodilator therapy for treating chronic cough.
abstract: OBJECTIVE
  Partial expiratory flow-volume curves have the potential to detect mild bronchoconstriction because they are not affected by the modulatory effects of deep inspiration. The aim of this study was to investigate the relationship between the efficacy of bronchodilator therapy (BDT) in treating the cough and to assess the increase in the expiratory flow of the partial flow-volume curve at 40% above the residual volume level (PEF40) caused by treatment with a short-acting beta-2 agonist (SABA) in patients with chronic nonproductive cough.
  
  
  METHODS
  We measured the reversibility of PEF40 caused by a SABA in 42 patients with chronic nonproductive cough at visit 1 (day 0). The patients received BDT for six days. The visual analogue scale (VAS) was used to assess the efficacy of BDT in treating coughing at visit 2 (day 7) (0 mm, 'no cough;' 100 mm, 'no change in coughing').
  
  
  RESULTS
  Reversibility of the PEF40 was correlated (r=0.690, p<0.001) with the VAS score determined at visit 2 and was higher in the patients with cough variant asthma (CVA) (44.9 ± 18.3%) than in those with atopic cough (13.4 ± 10.4%) (p<0.01).
  
  
  CONCLUSIONS
  Reversibility of the PEF40 predicted the efficacy of BDT in patients with chronic nonproductive cough and helped to identify patients with CVA.
authors.affiliation: Clinical Laboratory, Kanazawa University Hospital, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakade
authors.forename: Masaki
authors.initials: M
authors.lastname: Fujimura
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Ohkura
authors.forename: Masako
authors.initials: M
authors.lastname: Nakata
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nanbu
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Oe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Horita
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Sakai
authors.forename: Takashi
authors.initials: T
authors.lastname: Wada
mesh_terms: D058666:Adrenergic beta-2 Receptor Agonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D002908:Chronic Disease; D003371:Cough / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000187:drug effects*; D012129:Respiratory Function Tests; D016896:Treatment Outcome; D014797:Vital Capacity / Q000187:drug effects; D055815:Young Adult
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents