Background Adverse effects of glucocorticoids (GCT) upon the skeleton and markers of bone turnover have been documented but the mechanisms remain unclear.
Objectives To test of early changes in markers of bone turnover for three months of GCT and the influence of VDR.
Methods In fifty three patients (age 41,7 SD 12,6) with inflammatory diseases who received a dose greater than 5 mg of prednisone or equivalent (mean dose 1,9 g) for 3 months, the serum levels of parathyroid hormone (PTHi), 25-dihydroxyvitamin D, (Vit D), osteocalcin, alkaline phosphatase, and urine ratios of calcium/creatinine and deoxypyridinoline/creatinine, were determined baseline and 3 months after GCT. VDR genotypes were determined by PCR to demonstrate the presence (b) or absence (B) of a restriction target for Bsm I, in intron 7.
Results The patients with high baseline levels of PTHi showing lower levels of baseline VitD, (p = 0,003) and 3 months after of GCT the patients with lower levels of PTH have the higher levels of Vit D, (p = 0,001, r = 0,54). There were no significant differences in biochemical markers of bone remodelling between the three genotypes: bb, BB, and Bb VDR before and 3 months after GCT.
Conclusion These preliminary results suggest not effect of VDR genotype in the changes of the biochemical markers of bone remodelling for glucocorticoid therapy.