Bone Abstracts

Background: Association between high serum homocysteine (S-Hcy) levels and low bone mineral density (BMD) and increased fracture risk in postmenopausal women has been repeatedly documented. There are scarce data concerning S-Hcy and bone health in children and adolescents.

Patients and methods: We assessed S-Hcy levels in 37 children and adolescents (22 boys and 15 girls; mean age 13.9±3.5 years) with prevalent low-energy trauma fractures (mean 3.3±2.3 per patient) and/or low spinal L1–L4 BMD (below −2 S.D. Z-score; DXA Lunar GE). We also evaluated S-ALP, serum CrossLaps, osteocalcin (S-OC), body height, weight, and BMI. At the time of assessment, the children were not taking any drugs known to influence bone metabolism. The age-dependent parameters (S-Hcy, BMD, S-ALP, S-OC, S-Crosslaps, height, weight and BMI) were expressed as Z-scores±S.D.

Results: Mean S-Hcy Z-score was significantly higher (1.3±1.5; P<0.0001) and mean L1–L4 BMD Z-score was significantly lower (−1.7±1.3; P<0.0001), respectively, in comparison with reference values. S-ALP did not differ from reference values (P=0.88), while S-CrossLaps and S-OC were higher (1.2±1.8 and 0.4±0.5 respectively; P=0.001). Mean body height, body weight, and BMI Z-score was −0.05±1.31, 0.18±1.62 and 0.48±1.88, respectively, which did not differ from reference values. The body height, weight and BMI Z-scores positively correlated with L1–L4 BMD Z-score (r=0.44, 0.53 and 0.50, respectively; P=0.01). S-Hcy was inversely correlated to L1–L4 BMD (r=−0.33; P=0.05) and S-ALP (r=−0.40; P=0.02) and not related to number of prevalent fractures (r=0.01), S-osteocalcin (r=−0.22) or S-CrossLaps (r=−0.003). There were positive correlations between S-ALP and S-OC (r=0.58; P=0.01), S-ALP and S-Crosslaps (r=0.39; P=0.05), S-OC and S-Crosslaps (r=0.36; P=0.05), respectively. These results suggest increased bone turnover and negative influence of elevated S-Hcy on bone formation and BMD in children and adolescents with recurrent fractures.

Conclusion: Our results suggest that elevated S-Hcy should be considered a risk factor of impaired bone health in children and adolescents.