Characteristics of Patients with Chronic Cough Who Developed Classic Asthma during the Course of Cough Variant Asthma: A Longitudinal Study

Abstract

Background: Some patients develop asthmatic symptoms such as wheezing and dyspnea during the course of cough variant asthma (CVA), which are considered precursors of classical asthma. Objectives: To identify the characteristics of such patients, we investigated the nature of CVA patients with or without developing bronchial asthma in the longitudinal study. Methods: In 28 CVA patients whom we could observe over 5 years, duration of coughing, physical examination findings, pulmonary function and bronchial hyperresponsiveness to inhaled methacholine were retrospectively assessed. Results: Of these patients with CVA, 10 developed the asthmatic symptoms of wheezing and dyspnea (precursors of classical asthma) over 5 years. All these 10 patients showed marked bronchial hyperresponsiveness; however, there were no significant differences in the bronchial responsiveness to methacholine between patients with precursors of classical asthma and pure CVA patients who did not wheeze. The duration of coughing had a significant relationship with precursors of classical asthma. Seven patients with precursors of classical asthma developed wheezing in the first year and 1 patient each in the second, third and fourth year. Conclusions: These findings of a 5-year observation suggest that longer duration of coughing may be an important factor that develops precursors of classical asthma in patients with CVA.

Cough variant asthma patients are more depressed and anxious than classic asthma patients

“…The present results showed that CVA patients were generally younger and included more women than classic asthma patients, although there was no statistic difference in age of newly diagnosed patients. Given the previous report that CVA is a precursor of classic asthma and 30-40% of them have developed classic asthma [1,10,37], it is natural that CVA patients are less commonly elderly. Many studies have suggested that adult CVA patients are more likely to be females [10,11,[37][38][39], while in children, CVA was identified in slightly more boys than girls [40,41].…”

Comparison of Cause Distribution between Elderly and Non-Elderly Patients with Chronic Cough

“…Although wheezing and dyspnea may eventually develop in about 30% of patients with CVA [28], it is difficult to precisely predict who will progress to classical asthma [29]. Moreover, there is not enough evidence that inhaled corticosteroids will prevent the onset of classical asthma, or improve the pulmonary function and cough reflex sensitivity in CVA [30].…”

Pharmacotherapy of cough-variant asthma

“…Age, sex, atopy and pulmonary function tests were not found to predict typical asthma development, but more severe airway hyper-responsiveness and a higher degree of sputum eosinophilic inflammation were found more frequently in children who subsequently developed typical asthma [31]. In a study enrolling 28 CVA patients treated with theophylline and bronchodilators, but not with inhaled corticosteroids, who were followed up for 5 years, it was found that longer duration of coughing may be associated with a higher risk of typical asthma development [32]. In another study, predictors of progression to typical asthma were compared in CVA patients taking or not taking inhaled corticosteroids.…”