1. Department of Geriatrics, Qingdao Eighth People’s Hospital, Qingdao, Shandong 266121, China
2. Intensive Care Unit, Qingdao Eighth People’s Hospital, Qingdao, Shandong 266121, China
3. Department of Gastroenterology, Qingdao Eighth People’s Hospital, Qingdao, Shandong 266121, China