title: Phosphodiesterase 3 inhibition and cough in elderly asthmatics.
abstract: OBJECTIVE
  Cough is a common symptom of bronchial asthma, a chronic inflammatory airway disease. Recently, the therapeutic effects of selective phosphodiesterase (PDE) inhibitors have been focused on bronchial asthma. This study was designed to investigate the clinical effect of PDE 3 inhibition on cough reflex sensitivity in elderly patients with bronchial asthma.
  
  
  METHODS
  Effects of cilostazol, a PDE 3 inhibitor, on cough response to inhaled capsaicin were examined in 11 patients over 70 years with stable asthma in a randomized, placebo-controlled cross over study. Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough reflex sensitivity.
  
  
  RESULTS
  The cough threshold was significantly (p < 0.05) increased after two-week treatment with cilostazol (100 mg twice a day orally) compared with placebo [48.8 (GSEM 1.4) vs. 29.2 (GSEM 1.3) muM].
  
  
  CONCLUSIONS
  These findings indicate that PDE 3 inhibition may be a novel therapeutic option for elderly patients with asthma, especially for their cough symptoms.
authors.affiliation: The Department of Internal Medicine, Toyama City Hospital, Toyama, Japan. ishiura@tch.toyama.toyama.jp.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ishiura
authors.forename: Masaki
authors.initials: M
authors.lastname: Fujimura
authors.forename: Kouichi
authors.initials: K
authors.lastname: Nobata
authors.forename: Miki
authors.initials: M
authors.lastname: Abo
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Oribe
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Myou
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakamura