Preliminary findings: 25(OH)D levels and PTH are indicators of rapid bone accrual in pubertal children.
OBJECTIVE
The objective of this study was to evaluate the role of serum levels of 25(OH)D and PTH on the accumulation of whole body bone mass in a cohort of children.


METHODS
This was a longitudinal study (1.98 +/- 0.07 y) of sixty-nine children (89% Caucasian, 44% male) enrolled in a calcium supplementation trial. Bone area, bone mineral content (BMC) and density (BMD) of the whole body and radius were assessed using a QDR 2000 (Hologic, Inc) dual energy x-ray absorptiometer. Serum PTH and 25(OH)D were measured using radioimmunoassays.


RESULTS
Vitamin D stores were inversely related gain in bone area (p < 0.002), BMC (p < 0.002) BMD (p < 0.027), as well as to PTH levels (p < 0.0001). Compared to those with adequate vitamin D stores (>34 ng/ml), those who had consistently low vitamin D stores (18 ng/ml) had a 8% larger gain in bone area (p < 0.05); 11% in BMC (p < 0.05) and no differences in gain in BMD; after adjusting for baseline bone measurements, race, gender, season measured, Tanner stage, and calcium intake.


CONCLUSIONS
High normal PTH with low-normal 25(OH)D stores and moderate to high calcium intake may be beneficial to accruing larger bone size and BMC during puberty.
Tylavsky
Frances A
FA
University of Tennessee Health Science Center, Memphis, Tennessee, USA. ftylavsky@utmem.edu
Ryder
Kathryn M
KM
Li
Rongling
R
Park
Vicki
V
Womack
Catherine
C
Norwood
John
J
Carbone
Laura D
LD
Cheng
Sulin
S
D015502:Absorptiometry, Photon; D000135:Acid Phosphatase / Q000378:metabolism; D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects* / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000494:pharmacology; D001842:Bone and Bones / Q000378:metabolism*; D002136:Calcium, Dietary / Q000008:administration & dosage* / Q000494:pharmacology; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D015331:Cohort Studies; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood*; D011627:Puberty / Q000378:metabolism*; D011863:Radioimmunoassay; D018167:Receptors, Calcitriol / Q000378:metabolism; D012923:Social Class; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D015415:Biomarkers; D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary; D010281:Parathyroid Hormone; D018167:Receptors, Calcitriol; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000135:Acid Phosphatase