Introduction: Serum 25(OH)D concentrations for optimal bone metabolism in children is unknown. Only few data exist describing the effects of increasing serum 25(OH)D on bone metabolism markers.
Aim: The aim of the study was to explore the association between serum 25(OH)D and bone metabolism markers in children.
Patients and methods: Serum levels of bone formation (OC, P1NP) and bone resorption (CTx) markers (Cobas e411, Roche Diagnostics) were determined in 161 healthy children (mean age: 9.47±4.94 years; range: 1.9219.66). Vitamin D status was evaluated by serum levels of 25(OH)D and PTH (Cobas e411; Roche Diagnostics). Bone metabolism markers reference intervals was prepared according to age and gender.
Results: Serum 25(OH)D levels <10 ng/ml were described in 25.0% children, 1020 ng/ml in 40.8% children and >20 ng/ml in 34.2% cases. Only 12.5% patients have serum 25(OH)D >30 ng /ml. Positive correlations were observed among the three bone metabolism markers (R at range 0.670.76, P<0.001). The correlation between serum 25(OH)D and PTH (R=−0.26, P=0.002) indicate significant negative association between these parameters. Multivariate analysis for predictors of age-adjusted bone metabolism markers showed that serum 25(OH)D was strongly and positively associated with OC, P1NP and CTx in healthy children, explaining 10.3% of the variance in OC (P<0.001), 12.5% in P1NP (P<0.0001), and 16.2% in CTx (P<0.0001). Not significant effect of PTH on bone metabolism was evidenced in our study.
Conclusions: Strong and positive association of serum 25(OH)D with bone formation as well as resorption markers indicates that proper vitamin D status is very important for bone health especially in period of bone mass accrual.
18 May 2013 - 22 May 2013