A retrospective study of clinical features of cough variant asthma in Chinese adults

Abstract

BackgroundClinical features of cough variant asthma (CVA) in Chinese adults are largely uncertain.MethodsA total of 303 patients newly diagnosed as uncontrolled asthma (symptom control and future risk of adverse outcomes), including 175 CVA and 128 classic asthma (CA), were enrolled in this retrospective survey. Clinical features including basic characteristics, pulmonary function, airway hyperresponsiveness (AHR) and cell counts of induced sputum, were compared retrospectively. All patients were classified into four inflammatory subtypes based on the counts of induced sputum eosinophils and neutrophils as eosinophilic (E), neutrophilic (N), mixed granulocytic (M), and paucigranulocytic (P) subtypes. Inflammatory subtype distribution was also compared.ResultsCompared with CA patients, CVA patients were younger (P = 0.009), had a higher prevalence of female patients (P = 0.001), higher parameter values of baseline pulmonary function (P ≤ 0.01 for all), shorter duration of disease (P = 0.002), lower AHR (P = 0.001) and lower sputum eosinophil% (P = 0.009). There was a difference in the AHR distribution as the percentage of moderate and severe AHR in CVA was significantly lower than in CA (41.72% VS 64.70%, P = 0.001). The inflammatory subtype distribution was different as the proportion of E and M subtypes in CVA was lower than in CA (56.0% vs 67.19%, P = 0.049). The proportion of subtype P was the lowest and subtype M was the highest in both CVA and CA patients. There was a similar negative correlation of sputum eosinophil% with AHR in CVA and CA (r = − 0.337, P < 0.0001 and r = − 0.27, P = 0.026, respectively), and a positive correlation between sputum eosinophil% and improvement rate of FEV1 after inhalation of bronchodilator (ΔFEV1%) (r = 0.33, P = 0.01).ConclusionsCVA patients showed a better pulmonary function and lower airway inflammation in contrast to CA patients, which may participate in the pathogenesis of chronic cough in CVA.

Elevated Serum Levels of Herpes Virus Entry Mediator and IL-5 in Cough Variant Asthma Versus Classic Asthma Patients

“…The CVA group had a higher prevalence of female patients and a shorter duration of disease compared to the CA group, and the results are consistent with the earlier report. [14] Meanwhile, we also found noticed the routine PFT parameters for evaluating mechanical properties of the large, medium-sized, and small airways in CVA group were signi cantly greater than those in CA group. It may suggest that the decline of pulmonary function is relatively milder in CVA patients.…”

Elevated Serum Levels of Herpes Virus Entry Mediator and IL-5 in Cough Variant Asthma Versus Classic Asthma Patients

“…The CVA group had a higher prevalence of female patients and a shorter duration of disease compared to the CA group, and the results are consistent with earlier report. [14] Meanwhile, we also found noticed the routine PFT parameters for evaluating mechanical properties of the large, medium-size, and small airways in CVA group were signi cantly greater than those in CA group. It may suggest that the decline of pulmonary function is relatively milder in CVA patients.…”

Allergic shiners in a patient with cough-variant asthma: a case report

“…It is considered chronic when the duration is longer than 8 weeks in adults and adolescents older than 14 years old [ 2 ], and interferes with normal activity and daily life [ 3 ]. One of the most common causes of chronic cough is cough-variant asthma, a specific and atypical asthma phenotype, which accounts for approximately one-third of cases [ 4 ]. This phenotype of asthma is characterized by airway hyperresponsiveness, eosinophilic inflammation, and bronchodilator responsiveness without clinical manifestations such as wheezing and dyspnea [ 5 ].…”