The effects of teriparatide on the incidence of back pain in postmenopausal women with osteoporosis

Objectives: Back pain is a major cause of suffering, disability, and cost. The risk of developing back pain was assessed following treatment with teriparatide [rh(PTH 1-34)] in postmenopausal women with osteoporosis. Research design and methods: A secondary analysis of back pain findings from the global, multi-site Fracture Prevention Trial was conducted where postmenopausal women with prevalent vertebral fractures were administered teriparatide 20 mu g (n = 541) or placebo (n = 544) for a median of 19 months. Treatment-emergent back pain data were collected during adverse event monitoring, and spine radiographs were obtained at baseline and study endpoint. Main outcome measures: The risk of back pain stratified by severity of new or worsening back pain and the risk of back pain associated with both number and severity of new vertebral fractures. Results: Women randomized to teriparatide 20 mu g had a 31% reduced relative risk of moderate or severe back pain (16.5% vs. 11.5%, P = 0.016) and a 57% reduced risk of severe back pain (5.2% vs. 2.2%, P = 0.011). Compared with placebo, teriparatide-treated patients experienced reduced relative risk of developing back pain associated with findings of: one or more new vertebral fractures by 83% (6.5% vs. 1.1%, P < 0.001), two or more new vertebral fractures by 91% (2.5% vs. 0.20%, P = 0.004), and one or more new moderate or severe vertebral fractures by 100% (5.1% vs. 0.0%, P < 0.001). Conclusions. Teriparatide-treated women had reduced risk for moderate or severe back pain, severe back pain, and back pain associated with vertebral fractures. The mechanism of the back pain reduction likely includes the reduction both in severity and number of new vertebral fractures.