1. Marcus Institute for Aging Research, Hebrew Senior Life, Boston, MA, USA
2. Division of Geriatrics, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
3. Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
4. Harvard T.H.Chan School of Public Health, Boston, MA 02115, USA
5. PyeongChang Health Center and County Hospital, PyeongChang, Gangwon-Do, Republic of Korea
6. Division of Gerontology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, USA
7. Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA