[1] Univ Hosp Zurich, Dept Aging Med, Zurich, Switzerland
[2] Univ Hosp Zurich, Ctr Aging & Mobil, Zurich, Switzerland
[3] Univ Zurich, Zurich, Switzerland
[4] Charite Univ Med Berlin, Radiol Klin, Berlin, Germany
[5] Free Univ Berlin, Berlin, Germany
[6] Humboldt Univ, Berlin, Germany
[7] Univ Sheffield, Sch Med, Ctr Metab Dis, Sheffield, S Yorkshire, England
[8] Australian Catholic Univ, Mary MacKillop Inst Hlth Res, Melbourne, Vic, Australia
[9] Tufts Univ, Jean Mayer USDA Human Nutr Res Ctr Aging, Boston, MA 02111 USA
[10] Geneva Univ Hosp & Fac Med, Div Bone Dis, Geneva, Switzerland
[11] Private Hosp Bethanien, Spine Clin & Traumatol, Zurich, Switzerland
[12] Univ Zurich, Dept Aging Med, Zurich, Switzerland
[13] Zurich City Hosp Waid, Univ Clin Aging Med, Zurich, Switzerland