1 Intensive Care Unit of Geriatrics, Beijing Shijitan Hospital Affiliated to Capital Medicine University, No.10 Tieyi Road, Beijing, Haidian District, 100038, People's Republic of China.
2 Department of Pulmonary and Critical Care, Medicine, Beijing Shijitan Hospital Affiliated to Capital Medicine University, No.10 Tieyi Road, Beijing, Haidian District, 100038, People's Republic of China.
3 Department of Geriatrics, Beijing Shijitan Hospital Affiliated to Capital Medicine University, No.10 Tieyi Road, Beijing, Haidian District, 100038, People's Republic of China.
4 Department of Geriatrics, Beijing Shijitan Hospital Affiliated to Capital Medicine University, No.10 Tieyi Road, Beijing, Haidian District, 100038, People's Republic of China. [email protected].