Clinical characteristics of obese, fixed airway obstruction, exacerbation-prone phenotype and comorbidities among severe asthma patients: a single-center study.

"Declarations Ethics approval and consent to participateThis study was conducted in accordance with the Declaration of Helsinki and received permission from the ethics committee of Zhongshan hospital, Fudan University (approval number: B2019-020R). This study was exempt from informed consent by the approval of the ethics committee of Zhongshan hospital, Fudan University because of the retrospective nature of the study. Consent for publicationNot applicable. Competing interestsThe authors declare no competing interests. Competing interests The authors declare no competing interests."

"Funding This work was supported by National Natural Science Foundation of China (82270028, 81970060, 82000013, 82100028), Clinical Research Special Fund of Zhongshan Hospital (2020ZSLC26), Shanghai Municipal Key Clinical Specialty (shslczdzk02201), Clinical Research Plan of SHDC (SHDC2020CR1002A)."