Skeletal response to treatment with teriparatide (TPD) after bisphosphonate in post-menopausal women with osteoporosis and a high prevalence of secondary risk factors in real-life setting of a metabolic bone clinic; effect of age and vitamin D status

Purpose: Teriparatide (TPD) is a skeletal anabolic agent used in patients with severe post-menopausal osteoporosis (PMO) and steroid-induced osteoporosis who are at hish risk of fracture. Predictors of therapeutic response to teriparatide in real-life setting are not well characterised. We investigated potential factors associated with teriparatide response in post-menopausal women with established osteoporosis. Methods: We carried out a retrospective survey of 48 women, aged 73.2 [7.5] years with severe osteoporosis and prevalent fractures treated with TPD according to the NICE criteria. BMD was measured at baseline, 6-12 and 18-24 months at the lumbar spine (LS), total hip (TH) and femoral neck (FN). Bone turnover markers, serum 25 (OH)vitamin D were determined at 3-12 and 12-24 months. Results: BMD increased at 6-12 months (% change mean [SEM] 6.5 [1.1] p = 0.004) and 18-24 months (8.45 % [1.2] p<0.001) at the LS. A significant increase in BMD was observed at FN (3.1 [1.3] % p = 0.02). Changes in BMD at the TH was higher in patients younger than 73 years compared to older women (% change in BMD 4.13 [1.64] % v/s -1.7 [1.1] p = 0.007). Baseline 25 (OH) vitamin D correlated with change in P1NP at 3-12 months (r = 0.45 p = 0.049). Conclusions: TPD-induced changes in BMD at the TH appears may be dependent on age. Vitamin D status may influence the early anabolic effect to TPD. Our data suggest that these factors may be important considerations when initiating and optimising treatment with TPD, although further larger studies are needed to confirm these findings.