Endocrine Abstracts

Introduction: Some recent data indicates that high levels of homocysteine (Hcy) can be independent risk factor for osteoporosis and fractures in elderly. There are few explanations how homocysteine influence bone resorption and probably modify effect of therapy for osteoporosis. 1. Hcy interferes with collagen cross-linking. 2. High levels of Hcy specially stimulate resorptive activity of osteoclasts in vitro. 3. Hcy interfere bisphosphonates binding to hydroxyapatite.

The aim: To investigate is there a connection between levels of homocysteine and changes in levels of osteokalcin, β-crosslaps and ionized calcium during the therapy.

Materials and methods: We examined 40 women’s with diagnosed osteoporosis (DXA of lumbar spine or hip: T score or X-ray of the spine). All patients use alendronate 10 mg per day with 500 mg of calcium and 0.25 μg of activated vitamin D. Levels of homocysteine, osteocalcin (OC), β-crosslaps (CL) and ionized calcium were measured on baseline and after 6-8 weeks during the therapy. Results were linearly correlated.

Results: There was no significant correlation between baseline levels of homocysteine and osteocalcin (r=−0.1618, t=1.011, P>0.05) and β-crosslaps (r=−0.0199, t=0.123, P>0.05) before therapy. There was no correlation between levels of homocisteine with change in levels of β-crosslaps and osteocalcin during the therapy (CL: r=0.0737, t=0.3696, P>0.05, OC: r=−0.11262, t=0.55526, P>0.05). Homocysteine levels before therapy are slightly negatively correlated with levels of ionized calcium before therapy. (r=− 0.306, t=1.982, P>0.05, P<0.1).

Conclusions: In this preliminary study, there was no significant correlation between levels of homocysteine and biochemical bone markers before and during the antiresorptive treatment with alendronate. Although there is a suggestion for further investigations with more patients included.