Effects of risedronate on fracture risk in postmenopausal women with osteopenia.

UNLABELLED: This posthoc analysis of four trials studied the efficacy of risedronate to reduce fragility fractures in postmenopausal women with osteopenia (i.e., T-scores between -1 and -2.5). Risedronate reduced the fracture risk by 73% (p = 0.023) in this population of women with low femoral neck bone mass and no prevalent vertebral fractures. INTRODUCTION: Low bone mass represents an increasing health risk and burden. Half of fragility fractures occur in osteopenic women underscoring the need for treatments reducing fracture risk. This analysis reports the effect of risedronate to reduce fragility fracture risk in osteopenic women without prevalent vertebral fractures. METHODS: Postmenopausal women with osteopenia, defined as femoral neck T-score between -1 and -2.5 by DXA and no prevalent vertebral fractures, were identified from four controlled randomized trials (BMD Multinational, BMD North America, VERT Multinational and VERT North America). The risk reduction for fragility fractures in patients receiving 5 mg risedronate daily for 1.5 to 3 years compared to placebo was assessed. An additional sensitivity analysis excluded patients who were osteopenic at the femoral neck but had a BMD lower than -2.5 SD at the lumbar spine. RESULTS: Six hundred and twenty postmenopausal women with osteopenia were included, receiving either placebo (n = 309) or risedronate 5 mg (n = 311). Risedronate reduced the risk of fragility fractures by 73% over 3 years versus placebo (p = 0.023); cumulative fragility fracture incidence was 6.9% in placebo-treated versus 2.2% in risedronate-treated patients. The magnitude of the effect was similar in the sensitivity analysis subset. CONCLUSION: Risedronate significantly reduced the risk of fragility fractures in postmenopausal women with osteopenia (femoral neck T-score between -1 and -2.5 SD) and no prevalent vertebral fractures.

Risedronate decreases fracture risk in patients selected solely on the basis of prior vertebral fracture.

The aim of this study was to examine the effects of risedronate (5 mg/daily) in patients identified solely on the basis of a prior fragility fracture, without BMD as an inclusion criterion. A total of 1,802 patients were examined from the VERT-NA and VERT-MN clinical trials. Lateral radiographs (T4 to L4) were obtained at baseline and annually; incident fractures were evaluated using quantitative and semiquantitative methods at the central facility. BMD was measured at the lumbar spine and femoral neck by dual-energy X-ray absorptiometry. Secondary analyses evaluated vertebral fracture efficacy in patient subgroups categorized according to the presence of risk factors for osteoporosis at baseline (age, femoral neck BMD, lumbar spine BMD, more severe BMD, height, weight, body mass index, prevalent nonvertebral fracture status, smoking, and bone turnover marker levels). Over 3 years, risedronate reduced the risk of new vertebral fractures by 44% (95% CI, 28% to 56%) compared with placebo. In patients subgrouped according to the presence or absence of putative risk factors, the efficacy of risedronate was comparable across all groups (all treatment-by-non BMD subgroup interactions p > or =0.210). Adjustment for age, baseline BMD, and prevalent vertebral fractures on fracture risk gave results similar to the unadjusted analysis. In patients taking placebo, the incidence of new vertebral fracture was higher in several of the high-risk categories (elderly, T-score < or = -2.5 SD). In conclusion, the findings of this study suggest that risedronate is effective in patients identified solely on the basis of a prior fragility fracture and that the efficacy of risedronate in the reduction of vertebral fractures is largely independent of the presence of clinical risk factors for osteoporotic fracture.

Bone density threshold and other predictors of vertebral fracture in patients receiving oral glucocorticoid therapy.

OBJECTIVE: To evaluate predictors of vertebral fractures, including a threshold for bone mineral density (BMD), in patients receiving oral glucocorticoids (GCs). METHODS: Data were obtained from 2 randomized clinical trials (prevention and treatment trials of risedronate) using similar methods, but different inclusion criteria were applied with regard to prior exposure to GCs. Predictors of vertebral fracture in the placebo group were identified using Cox regression with forward selection. The BMD threshold analysis involved a comparison of the 1-year fracture risk in postmenopausal women receiving placebo in the GC trials with that in postmenopausal women not taking GCs in 3 other trials. RESULTS: The study population comprised 306 patients with baseline and 1-year followup data on vertebral fractures (111 receiving placebo and 195 receiving risedronate). In the placebo group, the statistically significant predictors of incident fracture were the baseline lumbar spine BMD (for each 1-point decrease in T score, relative risk [RR] 1.85, 95% confidence interval [95% CI] 1.06-3.21) and the daily GC dose (for each 10-mg dose increase, RR 1.62, 95% CI 1.11-2.36). In the BMD threshold analysis, compared with nonusers of GCs, patients receiving GCs were younger, had a higher BMD at baseline, and had fewer prevalent fractures; nevertheless, the risk of fracture was higher in the GC users compared with nonusers (adjusted RR 5.67, 95% CI 2.57-12.54). The increased risk of fracture was observed in GC users regardless of whether osteoporosis was present. CONCLUSION: The daily, but not cumulative, GC dose was found to be a strong predictor of vertebral fracture in patients receiving GCs. At similar levels of BMD, postmenopausal women taking GCs, as compared with nonusers of GCs, had considerably higher risks of fracture.