Abstract

Bisphosphonates (BPs) are anticatabolic drugs of choice for treating bone diseases, including bone metastases. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is one of the possible complications. Crosslaps (CTX) could be used as biochemical marker for risk of developing ONJ. Vitamin D (VD) may be involved in this condition. VD status and CTX levels were evaluated and compared in BPtreated women without BRONJ (Group I; n=28) and with BRONJ (Group II; n=58). Women were older and duration of BP use was longer in Group II (p=0.0000036). No differences in calcemia, phosphatemia, or CTX levels were observed; BAP levels were significantly higher and 25OHD were significantly lower in Group II (p=0.040 and p=0.035, respectively). The percentage of subjects with CTX levels between 100 and 149mg/mL was similar in both groups. VD deficiency was observed in 18% of subjects in Group II but in none of the subjects in Group I. No significant differences in the percentage of subjects with VD insufficiency and sufficiency were observed between groups (Group I: 50%; Group II: 40%). Conclusion: CTX levels did not prove useful as predictors of risk for developing BRONJ. The high percentage of women with VD deficiency who developed BRONJ suggests a possible relationship between both conditions and highlights the importance of assessing Vitamin D status.

Keywords: Bisphosphonates; Osteonecrosis of the jaw; Women; Vitamin D; CTX