Characteristics of different asthma phenotypes associated with cough: a prospective, multicenter survey in China
Jianmeng Zhou, Fang Yi, Feng Wu, Pusheng Xu, Meihua Chen, Huahao Shen, Lin Lin, Yunhui Zhang, Suyun Li, Changgui Wu, Yadong Yuan, Gang Wang, Xianwei Ye, Ping Zhang, Huaping Tang, Qianli Ma, Lan-qing Huang, Zhongmin Qiu, Haiyan Deng, Chen Qiu, Guochao Shi, Jiayu Pan, Wei Luo, Kian Fan Chung, Nanshan Zhong, Kefang Lai, the CPA Cohort Study Group, Ruchong Chen, Wei‐jie Guan, Yanqing Xie, Mei Jiang, Jie Gao, Wen Hua, Guangyun Cai, Cuiyi Chen, Mingjuan Zhou, Yanyan Xu, Minghang Wang, Yimin Guo, Xue Li, Lei Liu, Hongmei Yao, Hong Wen, Jianyou Chen, Xuemei Zhang, Zhiping Zhang, Yu Li, Dandan Chen, Wei Du, Qiaoli Chen, Hu Li, Wen Peng, Liting Zhang, Jiaman Tang, Baojuan Liu, Chen Zhan, Lianrong Huang, Xiaomei Chen
Abstract
BACKGROUND: Asthma is a heterogeneous disease with variable symptoms, which presents with cough either as the sole or predominant symptom with or without wheezing. We compared the clinical and pathophysiological characteristics of cough predominant asthma (CPA), cough variant asthma (CVA) and classic asthma (CA) in order to determine any differential phenotypic traits. METHODS: In 20 clinics across China, a total of 2088 patients were finally recruited, including 327 CVA, 1041 CPA and 720 CA patients. We recorded cough and wheezing visual analogue scale, Leicester cough questionnaire (LCQ) and asthma control test scores. Fractional exhaled nitric oxide (FeNO), induced sputum cell counts, and capsaicin cough challenge were also measured and compared. RESULTS: CPA patients more frequently presented with cough as the initial symptom, and laryngeal symptoms (p < 0.001), had less symptoms related with rhinitis/sinusitis and gastroesophageal reflux (p < 0.05) than CA patients. Comorbidities including rhinitis and gastroesophageal reflux were similar, while the proportion of COPD and bronchiectasis was higher in CA patients. There were no differences in FeNO levels, sputum eosinophil and neutrophil counts, FEV1 (%pred) decreased from CVA to CPA to CA patients (p < 0.001). Cough sensitivity was higher in CVA and CPA compared to CA (p < 0.001), and was positively correlated with LCQ scores. CONCLUSIONS: CVA, CPA and CA can be distinguished by the presence of laryngeal symptoms, cough sensitivity and airflow obstruction. Asthma-associated chronic cough was not associated with airway inflammation or comorbidities in our cohort. Trial registration The Chinese Clinical Trial Registration Center, ChiCTR-POC-17011646, 13 June 2017.