Sclerostin in institutionalized elderly women: associations with quantitative bone ultrasound, bone turnover, fractures, and mortality.
OBJECTIVE
To evaluate the association between levels of circulating sclerostin (an emerging biomarker and important regulator of bone formation) and laboratory parameters of bone and mineral metabolism, bone mineral density and quality measured using quantitative ultrasound (QUS), fracture risk, and mortality.


METHODS
Prospective cohort study.


METHODS
Austrian nursing homes (N = 95).


METHODS
Female nursing home residents aged 70 and older (mean 84 ± 6; N = 539).


METHODS
Serum sclerostin, bone turnover markers, and bone mineral density and quality were measured at baseline. Participants were followed for clinical fractures and all-cause mortality.


RESULTS
Partial correlation analysis adjusted for age, weight, and renal function revealed a significant positive correlation between sclerostin levels and calcaneal stiffness and radial and phalangeal speed of sound (all P < .01) and a significant negative correlation between sclerostin levels and osteocalcin, serum C-terminal telopeptide of type I collagen, and parathyroid hormone (PTH; P < .05). After a mean follow-up of 27 ± 8 months, 139 participants (26%) had died and 64 had a hip or other nonvertebral fracture (12%). Sclerostin was not predictive of mortality. In women with a negative fracture history, it was significantly but not linearly associated with fracture risk.


CONCLUSIONS
In institutionalized elderly women, there is a significant relationship between serum sclerostin levels and QUS indices, bone turnover, and PTH, but sclerostin was not strongly associated with important clinical outcomes. Thus, it remains unclear whether sclerostin is a clinically useful predictor of fractures or mortality, at least in this setting.
Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria.
Karin
K
Amrein
Harald
H
Dobnig
Doris
D
Wagner
Claudia
C
Piswanger-Sölkner
Thomas R
TR
Pieber
Stefan
S
Pilz
Andreas
A
Tomaschitz
Hans Peter
HP
Dimai
Astrid
A
Fahrleitner-Pammer
D048868:Adaptor Proteins, Signal Transducing; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D019485:Bone Morphogenetic Proteins / Q000097:blood*; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000378:metabolism*; D005260:Female; D050723:Fractures, Bone / Q000097:blood* / Q000000981:diagnostic imaging / Q000378:metabolism / Q000401:mortality*; D005819:Genetic Markers; D006801:Humans; D007326:Institutionalization; D011446:Prospective Studies; D018570:Risk Assessment; D014463:Ultrasonography
D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; D005819:Genetic Markers; C422903:SOST protein, human
bone turnover; fracture risk; mortality; nursing home; sclerostin