Clinical and biological determinants of sclerostin plasma concentration in hemodialysis patients.
BACKGROUND
Sclerostin is a potent inhibitor of bone formation, but the meaning of its serum levels remains undetermined. We evaluated the association between sclerostin levels and clinical or biological data in hemodialyzed patients (HD), notably parathormone (PTH), biomarkers of bone turnover, vascular calcifications and mortality after 2 years.


METHODS
164 HD patients were included in this observational study. The calcification score was assessed with the Kauppila method. Patients were followed for 2 years.


RESULTS
Median sclerostin levels were significantly (p < 0.0001) higher in HD versus healthy subjects (n = 94) (1,375 vs. 565 pg/ml, respectively). In univariate analysis a significant association (p < 0.05) was found between sclerostin and age, height, dialysis vintage, albumin, troponin, homocysteine, PTH, C-terminal telopeptide of collagen type I, bone-specific alkaline phosphatase and osteoprotegerin, but not with the calcification score. In a multivariate model, the association remained with age, height, dialysis vintage, troponin, homocysteine, phosphate, PTH, but also with vascular calcifications. Association was positive for all variables, except PTH and vascular calcifications. The baseline sclerostin concentration was not different in survivors and non-survivors.


CONCLUSIONS
We confirm a higher concentration of sclerostin in HD patients, a positive association with age and a negative association with PTH. A positive association with phosphate, homocysteine and troponin calls for additional research. The clinical interest of sclerostin to assess vascular calcifications in HD is limited and no association was found between sclerostin and mortality.
Nephrology-Dialysis-Transplantation, University of Liège, CHU Sart Tilman, Liège, Belgium.
Pierre
P
Delanaye
Jean-Marie
JM
Krzesinski
Xavier
X
Warling
Martial
M
Moonen
Nicole
N
Smelten
Laurent
L
Médart
Olivier
O
Bruyère
Jean-Yves
JY
Reginster
Hans
H
Pottel
Etienne
E
Cavalier
D048868:Adaptor Proteins, Signal Transducing; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D019485:Bone Morphogenetic Proteins / Q000097:blood*; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D006435:Renal Dialysis; D061205:Vascular Calcification / Q000097:blood
D048868:Adaptor Proteins, Signal Transducing; D015415:Biomarkers; D019485:Bone Morphogenetic Proteins; D005819:Genetic Markers; D010281:Parathyroid Hormone; C422903:SOST protein, human