title: Aging deteriorated perception of urge-to-cough without changing cough reflex threshold to citric acid in female never-smokers.
abstract: BACKGROUND
  The effect of aging on the cognitive aspect of cough has not been studied yet. The purpose of this study is to investigate the aging effect on the perception of urge-to-cough in healthy individuals.
  
  
  METHODS
  Fourteen young, female, healthy never-smokers were recruited via public postings. Twelve elderly female healthy never-smokers were recruited from a nursing home residence. The cough reflex threshold and the urge-to-cough were evaluated by inhalation of citric acid. The cough reflex sensitivities were defined as the lowest concentration of citric acid that elicited two or more coughs (C2) and five or more coughs (C5). The urge-to-cough was evaluated using a modified the Borg scale.
  
  
  RESULTS
  There was no significant difference in the cough reflex threshold to citric acid between young and elderly subjects. The urge-to-cough scores at the concentration of C2 and C5 were significantly smaller in the elderly than young subjects. The urge-to-cough log-log slope in elderly subjects (0.73 ± 0.71 point · L/g) was significantly gentler than those of young subjects (1.35 ± 0.53 point · L/g, p < 0.01). There were no significant differences in the urge-to-cough threshold estimated between young and elderly subjects.
  
  
  CONCLUSIONS
  The cough reflex threshold did not differ between young and elderly subjects whereas cognition of urge-to-cough was significantly decreased in elderly subjects in female never-smokers. Objective monitoring of cough might be important in the elderly people.
authors.affiliation: Department of Internal Medicine and Rehabilitation Science, Tohoku University Graduate School of Medicine, Sendai, Japan. sebihara@med.tohoku.ac.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ebihara
authors.forename: Takae
authors.initials: T
authors.lastname: Ebihara
authors.forename: Masashi
authors.initials: M
authors.lastname: Kanezaki
authors.forename: Peijun
authors.initials: P
authors.lastname: Gui
authors.forename: Miyako
authors.initials: M
authors.lastname: Yamasaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Arai
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kohzuki