[1] Sapienza Univ Rome, Dept Clin Internal Anesthesiol & Cardiovasc Sci, I-00161 Rome, Italy
[2] ASL Bari, Osped F Perinei, Nephrol & Dialysis Unit, I-70022 Bari, Italy
[3] Natl Res Council CNR, Inst Clin Physiol, Sect Biostat, I-89124 Reggio Di Calabria, Italy
[4] Geneva Univ Hosp, Dept Med, Serv Bone Dis, CH-1205 Geneva, Switzerland
[5] Fac Med, CH-1205 Geneva, Switzerland
[6] Hosp Badalona Germans Trias & Pujol, Dept Nephrol, Badalona 08916, Spain
[7] Res Inst Germans Trias & Pujol, REMAR IGTP Grp, Can Ruti Campus, Badalona 08916, Spain
[8] Univ Genoa, Nephrol Dialysis & Transplantat, I-16132 Genoa, Italy
[9] Policlin San Martino, I-16132 Genoa, Italy
[10] Alma Mater Studiorum Univ Bologna, Nephrol Dialysis & Renal Transplant Unit, Azienda Osped Univ Bologna, IRCCS, I-40126 Bologna, Italy
[11] Univ Campania Luigi Vanvitelli, Div Nephrol, I-80137 Naples, Italy
[12] Fdn Italiana Ric Malattie Osso FIRMO Onlus, I-50129 Florence, Italy
[13] Univ Milano Bicocca, Dept Stat & Quantitat Methods, Unit Biostat Epidemiol & Publ Hlth, I-20126 Milan, Italy
[14] St Anna Hosp, Dept Nephrol & Dialysis, ASST Lariana, I-22042 Como, Italy
[15] Natl Res Council CNR, Inst Clin Physiol, I-56124 Pisa, Italy
[16] Univ Padua, Dept Med & Surg, I-35128 Padua, Italy