Assessment of the Relationship Between Age and the Effect of Risedronate Treatment in Women with Postmenopausal Osteoporosis: A Pooled Analysis of Four Studies

Abstract

OBJECTIVES:To quantify the effect of age on the incidence of osteoporosis-related fractures and of risedronate treatment on fracture risk in different age groups in women with postmenopausal osteoporosis. DESIGN: Data from four randomized, double-blind, placebo-controlled, Phase III studies were pooled and analyzed. PARTICIPANTS: The analysis population (N 5 3,229) consisted of postmenopausal women with osteoporosis as determined on the basis of prevalent vertebral fractures, low bone mineral density (BMD), or both. INTERVENTION: Patients had received risedronate 5 mg daily or placebo for 1 to 3 years. MEASUREMENTS: The endpoints of interest were the incidence of osteoporosis-related fractures, clinical fractures, nonvertebral fractures, and morphometric vertebral fractures. The effect of age on fracture risk and treatment benefit was examined using Cox regression models with age and treatment as explanatory variables. The 3-year fracture risk was estimated for patients in each treatment group at a given age. RESULTS: Irrespective of treatment, fracture risks were greater in older patients (Po.001). On average, for every 1-year increase in age, a patient's risk for osteoporosisrelated fracture increased 3.6% (95% confidence interval 5 2.3-5.0%). Irrespective of age, risedronate treatment reduced fracture risk 42%. Risedronate-treated patients had fracture risks similar to those of placebo-treated patients 10 to 20 years younger. CONCLUSION: Patients treated with risedronate have a significantly lower fracture risk, similar to that of untreated patients 10 to 20 years younger. J Am Geriatr Soc 58:658-663, 2010.

Anti‐fracture efficacy of zoledronate in subgroups of osteopenic postmenopausal women: secondary analysis of a randomized controlled trial

“…The upper tertile for age extends from 73 to 91 years at baseline and from 79 years upwards at trial‐end. Fracture prevention is still apparent in this group, addressing an ongoing concern that efficacy of osteoporosis treatments has not been clearly demonstrated in elderly women . This study did not provide calcium supplements to participants, yet still demonstrated anti‐fracture efficacy in their absence.…”

Effect of Bisphosphonates on Fracture Outcomes Among Frail Older Adults

“…In bisphosphonate fracture trials, subgroup analyses have consistently demonstrated efficacy among the oldest individuals [39][40][41] and those with neurologic impairment, 42,43 though these estimates were imprecise and not directly representative of frail adults or NH residents. In the Fracture Intervention Trial comparing alendronate vs placebo among 3658 community-dwelling postmenopausal women, the NNT was 189 over 2 years of follow-up in the oldest subgroup (patients aged 75-85 years), which is similar to our 3-year estimate of 239.…”

Effectiveness of Teriparatide in Women Over 75 Years of Age with Severe Osteoporosis: 36-Month Results from the European Forsteo Observational Study (EFOS)

“…For risedronate, there was a significant 44 % reduction in the risk of vertebral fractures (relative to placebo) in women aged 80 years or above but no significant difference in the incidence of nonvertebral fractures [15]. A pooled analysis of RCTs in postmenopausal women with osteoporosis found that, despite a 4 % increase in the risk of fracture for every 1-year increase in age, there was a 46 % reduction in the risk of clinical fracture over 3 years with risedronate treatment [17]. For zoledronic acid, post hoc subgroup analysis of pooled data from the HORIZON trials found significant reductions (vs. placebo) in the risk of any clinical fracture (35 %), clinical vertebral fractures (66 %), and nonvertebral fractures (27 %) in postmenopausal women aged ≥75 years [16].…”