Contribution of bone turnover markers to bone mass in pubertal boys and girls.
OBJECTIVE
The association between bone turnover markers and bone mass in adolescence is not clear. We aimed to evaluate the associations between bone turnover markers and bone mineral content (BMC), density (BMD) and area (BMA).


METHODS
A total of 56 adolescents (25 boys, 12.5-17.5 years) participated in the study.


METHODS
Bone mass and physical activity (PA) were measured using dual energy X-ray absorptiometry and accelerometers. Osteocalcin and amino-terminal propeptide of type I procollagen (PINP), as markers of bone formation, and beta-isomer of the C-terminal telopeptide of type I collagen, as marker of bone resorption were also measured. Sexual maturation, weight, height and average PA were considered as confounders.


RESULTS
Positive correlations (Pearson) were observed among the three bone turnover markers (r = 0.7-0.9). Stepwise multiple linear regression analyses showed that PINP was strong and negatively associated with BMC, BMD and BMA in girls, explaining 24.9% of the variance in BMC, 25.6% in BMD and 16.3% in BMA.


CONCLUSIONS
PINP is a strong predictor of bone related variables in pubertal girls.
GENUD (Growth, Exercise, Nutrition and Development) Research Group, University of Zaragoza, Zaragoza, Spain. Igracia@unizar.es
Luis
L
Gracia-Marco
Francisco B
FB
Ortega
David
D
Jiménez-Pavón
Gerardo
G
Rodríguez
Jara
J
Valtueña
Angel E
AE
Díaz-Martínez
Marcela
M
González-Gross
Manuel J
MJ
Castillo
Germán
G
Vicente-Rodríguez
Luis A
LA
Moreno
D015502:Absorptiometry, Photon; D000293:Adolescent; D015415:Biomarkers / Q000378:metabolism; D015519:Bone Density / Q000502:physiology; D016723:Bone Remodeling / Q000502:physiology*; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology; D011627:Puberty / Q000502:physiology*
D015415:Biomarkers