1. Health Management Institute, Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese People’s Liberation Army General Hospital , Beijing , China
2. The 6th Health Department, Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese People’s Liberation Army General Hospital , Beijing , China
3. Health Management Institute, Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese People’s Liberation Army General Hospital , 28# Fuxing Road, Haidian District , Beijing 100853 , China