Predictive factors for achievement of treatment goals in patients with postmenopausal osteoporosis treated with denosumab.

OBJECTIVES: To investigate efficacy of long-term treatment with denosumab and predictive factors for achievement of treatment goals in patients with postmenopausal osteoporosis (PMO). METHODS: We enrolled 111 PMO patients who had T-scores ≤-2.5 either at the lumbar spine (L-) or femoral neck (FN-), who had never been treated for osteoporosis, and who could be followed for at least 3 years. We first evaluated changes in bone mineral density (BMD) for up to 7 years. We next defined the treatment goal as the achievement of a T-score >-2.5 at month 36 and performed multivariate analysis to identify predictive factors for achievement of the goal. RESULTS: Lumbar spine- and femoral neck bone-mineral density increased yearly for 7 years. Among 87 patients with baseline L-T-scores ≤-2.5, better baseline L-T-scores predicted achievement of L-T-scores >-2.5 at month 36. The cut-off value for baseline L-T-score was -3.4. Among 76 patients with baseline FN-T-scores ≤-2.5, better baseline FN-T-scores predicted achievement of FN-T-scores >-2.5 at month 36. The cut-off value for baseline FN-T-scores was -2.8. CONCLUSIONS: Long-term treatment with denosumab was effective in PMO patients. As better baseline T-score predicted achievement of T-scores >-2.5, early initiation of treatment will contribute to better outcome.