1. Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, and
2. Institute of Respiratory Medicine, School of Medicine, Tongji University, Shanghai, China;
3. Department of Respiratory Medicine, Branch of National Clinical Research Center for Respiratory Disease, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China; and
4. Department of Respiratory and Critical Care Medicine, Ruijin Hospital and
5. Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China