Effects of denosumab on bone mineral density and bone turnover markers in rheumatoid arthritis patients switching from bisphosphonates

BACKGROUND: To compare the efficacy of 12-month denosumab treatment on bone mineral density (BMD) and bone turnover markers (BTMs) between treatment-naïve osteoporosis patients with rheumatoid arthritis (RA) and those with previous bisphosphonate (BP) therapy. METHODS: A total of 36 RA patients with osteoporosis completed 12-month follow-up. Twenty-five patients were osteoporotic treatment-naïve (naïve group), and 11 patients were previously treated with BPs (switch group) (average 7.9 years). BMD and BTMs were measured before and 6 and 12 months after treatment. RESULTS: BTM levels were higher in the naïve group at baseline. However, the same level of suppression was achieved at 6 months in both groups. Spine BMD increased significantly in both groups. There was no significant difference in the mean percent changes of BMD of the spine (naïve group: 6.8 ± 0.8, switch group: 5.1 ± 1.5), femoral neck (2.9 ± 1.4, 2.9 ± 1.3), and total hip (1.7 ± 0.9, 1.4 ± 1.1) between these two groups at 12 months. CONCLUSIONS: The effects of denosumab on BMD and BTMs of the switch group after long-term BP treatment are comparable to those of the naïve group in RA patients. Thus, switching BPs to denosumab is one of the useful options to treat osteoporosis with RA.