Features of cough variant asthma and classic asthma during methacholine-induced brochoconstriction: a cross-sectional study.
Cough
; 5: 3, 2009 Mar 09.
Article
em En
| MEDLINE
| ID: mdl-19272144
ABSTRACT
BACKGROUND:
Little is known regarding mechanistic and phenotypic differences between cough variant asthma (CVA), presenting with a chronic cough as the sole symptom that responds to bronchodilators, and classic asthma with wheezing during methacholine inhalation. Here we reported airway sensitivity, airway reactivity, and as the main concern, the appearance of cough and wheezes during methacholine inhalation in patients with CVA or classic asthma.METHODS:
We cross-sectionally examined the degrees of airway sensitivity, the point where resistance started to increase, and reactivity, the slope of the methacholine-resistance curve, and the appearance of cough and wheezes in steroid-naïve adult patients with classic asthma (n = 58) or CVA (n = 55) while they were continuously inhaling methacholine during simultaneous measurement of respiratory resistance.RESULTS:
Patients with CVA were less sensitive and less reactive to inhaled methacholine and wheezed less frequently but coughed more frequently during methacholine-induced bronchoconstriction than did patients with classic asthma. Multivariate analysis revealed that airway hypersensitivity and lower baseline FEV1/FVC were associated with the appearance of wheezes, whereas a diagnosis of CVA was associated with coughing.CONCLUSION:
There are mechanistic and phenotypic differences between CVA and classic asthma during methacholine inhalation. Frequent coughing during bronchoconstriction may be a distinctive feature of CVA.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article