Reduced bone mineral density and increased bone turnover in Prader-Willi syndrome compared with controls matched for sex and body mass index--a cross-sectional study.
OBJECTIVE
To study bone mineral status, body composition, and biochemical markers of bone turnover in Prader-Willi syndrome (PWS).


METHODS
Eight subjects with PWS (three males, five females; mean age, 24 years [range 16-41]) were included. Each subject was compared with an age-, sex- and body mass index-matched control randomly drawn from the background population. Bone mineral density (BMD), lean body mass, and fat mass were measured. Plasma PINP, PIIINP, osteocalcin, total alkaline phosphatase, bone-specific alkaline phosphatase, C-terminal telopeptide of type I collagen, and urine cross-linked N-terminal telopeptide of type I collagen were measured as biochemical markers of bone and collagen turnover.


RESULTS
The PWS patients had significantly lower whole-body BMD (mean +/- SD, 1.020 +/- 0.041 vs 1.237 +/- 0.118 g/cm(2); 2p <.01) than controls due to lower bone mineral content (BMC: 2291 +/- 607 vs 2825 +/- 409 g; 2p=.02). Resorptive and formative bone markers were significantly elevated in patients compared with controls. Plasma testosterone was low in male patients (3.50 +/- 4.97 vs 19.2 +/- 8.78 nmol/L, 2p=.05), whereas no difference in plasma estradiol was present.


CONCLUSIONS
The patients had a low BMD due to a high bone turnover. This high turnover was probably linked to sex steroid deficiency.
Vestergaard
Peter
P
Department of Endocrinology and Metabolism C, Aarhus Amtssygehus, Aarhus University Hospital and Faculty of Health Sciences, Aarhus University, Aarhus, Denmark. p-vest@post4.tele.dk
Kristensen
Kurt
K
Bruun
Jens M
JM
Østergaard
John R
JR
Heickendorff
Lene
L
Mosekilde
Leif
L
Richelsen
Bjørn
B
D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D001823:Body Composition; D015519:Bone Density; D016723:Bone Remodeling / Q000502:physiology*; D001862:Bone Resorption / Q000378:metabolism*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D011218:Prader-Willi Syndrome / Q000503:physiopathology*; D018709:Statistics, Nonparametric
D015415:Biomarkers