Publication:

Vitamin D receptor gene polymorphism in patients with aseptic necrosis of the femoral head: a comparative cross-sectional study

Background This study explored the correlation of the Met1Thr (rs2228570) polymorphism of the vitamin D receptor (VDR) gene with aseptic necrosis of the femoral head (ANFH).

Methods This comparative cross-sectional study consisted of 74 patients divided into group 1 of 44 patients with ANFH and group 2 of 30 patients with hip osteoarthritis stage 3 by Kellgren-Lawrence classification. The VDR genotyping was conducted on venous blood samples. Serum vitamin D3 and osteocalcin were quantified via enzyme immunoassays. Statistical analyses consisted of χ² tests for genotype distribution and Mann-Whitney U-tests for biochemical parameters, considering for non-normal distributions.

Results There were no statical significant differences were observed in Met1Thr genotype distribution between ANFH and osteoarthritis groups (χ²=2.081; p=0.353). The carriers of the G (Thr) allele revealed a non-significant pattern toward elevated ANFH risk (OR=2.16; 95% CI 0.74-6.31). Both groups showed severe vitamin D deficiency (median 25(OH)D<30 ng/ml) and significantly reduced osteocalcin levels, reflecting reduced bone turnover rate. No statistically significant differences in Vitamin D3 or osteocalcin levels were noted between groups.

Conclusions Severe vitamin D deficiency and suppressed osteoblastic activity distinguished both ANFH and osteoarthritis. Although the Met1Thr VDR polymorphism was more common in ANFH patients, its connection with disease risk was not statistically significant. These findings suggest vitamin D deficiency as a key risk factor and highlight further research on VDR polymorphisms in larger cohorts.