1. Division of Endocrinology and Diabetes, University Campus Bio-Medico di Roma, Rome, Italy
2. Division of Bone Mineral Diseases, Washington University in Saint Louis, Saint Louis, Missouri
3. Vita-Salute San Raffaele University, Milan, Italy
4. Clinical Transplant Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS Ospedale San Raffaele, Milan, Italy
5. Geriatric Unit, University Campus Bio-Medico di Roma, Rome, Italy
6. Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
7. Centers for Disease Control and Prevention, Atlanta, Georgia
8. Department of Medicine, University of California, San Francisco, San Francisco, California
9. Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California
10. Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts
11. Department of Medicine, Harvard Medical School, Boston, Massachusetts
12. Division of Gerontology, Beth Israel Deaconess Medical Center, Boston, Massachusetts