Efficacy of osteoporosis pharmacotherapies in preventing fracture among oral glucocorticoid users: a network meta-analysis

Efficacy of osteoporosis medication is not well-established among patients taking oral glucocorticoids. We assessed the efficacy of approved osteoporosis pharmacotherapies in preventing fracture by combining data from randomized controlled trials. Teriparatide, risedronate, and etidronate were associated with decreased vertebral fracture risk.

INTRODUCTION

Several osteoporosis drugs are approved for the prevention and treatment of glucocorticoid (GC)-induced osteoporosis. However, the efficacy of these treatments among oral GC users is still limited. We aimed to examine the comparative efficacy of osteoporosis treatments among oral GC users.

METHODS

We updated a systematic review through to March 2015 to identify all double-blinded randomized controlled trials (RCTs) that examined osteoporosis treatment among oral GC users. We used a network meta-analysis with informative priors to derive comparative risk ratios (RRs) and 95 % credible intervals (95 % CrI) for vertebral and non-vertebral fracture and mean differences in lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD). Treatment ranking was estimated using the surface under the cumulative ranking curve (SUCRA) statistic. A meta-regression was completed to assess a subgroup effect between patients with prior GC exposures and GC initiators.

RESULTS

We identified 27 eligible RCTs examining nine active comparators. Etidronate (RR, 0.41; 95%CrI = 0.17-0.90), risedronate (RR = 0.30, 95%CrI = 0.14-0.61), and teriparatide (RR = 0.07, 95%CrI = 0.001-0.48) showed greater efficacy than placebo in preventing vertebral fractures; yet, no treatment effects were statistically significant in reducing non-vertebral fractures. Alendronate, risedronate, and etidronate increased LS BMD while alendronate and raloxifene increased FN BMD. In preventing vertebral fractures, teriparatide was ranked as the best treatment (SUCRA: 77 %), followed by risedronate (77 %) and zoledronic acid (76 %). For non-vertebral fractures, teriparatide also had the highest SUCRA (69 %), followed by risedronate (64 %). No subgroup effect was identified with regards to prior GC exposure.

CONCLUSIONS

Despite weak trial evidence available for fracture prevention among GC users, we identified several drugs that are likely to prevent osteoporotic fracture. Teriparatide, risedronate, and etidronate were associated with decreased vertebral fracture risk.

Fracture risk in oral glucocorticoid users: a Bayesian meta-regression leveraging control arms of osteoporosis clinical trials

Little data exist on the frequency of fracture among oral glucocorticoid users. We examined the effect of oral glucocorticoids on fracture incidence using data from randomized controlled trials. Patients starting glucocorticoids had a higher probability of fracture and decline in bone mineral density compared to chronic glucocorticoid users.

INTRODUCTION

Oral glucocorticoids (GCs) are the leading cause of secondary osteoporosis. However, there have been few studies that quantify the rate of fracture among GC users. We sought to provide a pooled estimate of fracture risk from randomized controlled trials (RCTs) of GC-treated patients.

METHODS

We updated a MEDLINE search published by the American College of Rheumatology through to March 2015 and identified RCTs of osteoporosis therapies that reported fracture and bone mineral density (BMD) among oral GC users. We restricted the analysis to placebo or control arms. RCT arms were stratified by GC exposure at enrolment to GC initiators (≤6 months) and chronic GC users (>6 months). Bayesian meta-regression was used to estimate the annual probability of vertebral fracture (primary), non-vertebral fracture and percentage change in lumbar spine and femoral neck BMD.

RESULTS

The annual incidence of vertebral and non-vertebral fracture was 5.1 % (95 % CrI = 2.8-8.2) and 2.5 % (95 % CrI = 1.2--4.2) among GC initiators, and 3.2 % (95 % CrI = 1.8-5.0) and 3.0 % (95 % CrI = 0.8-5.9) among chronic GC users. Our meta-regression identified a non-significant effect of group-level variables (mean age, mean BMD, mean GC daily dose, patients with previous vertebral fractures, proportion of women and adjuvant used) on vertebral fracture rate.

CONCLUSION

Our study found higher vertebral fracture incidence among GC initiators, yet a relative decline in fracture incidence with longer exposure. Our findings suggest that fracture incidence among oral GC users may be more common than previously estimated. Optimizing GC-induced osteoporosis management during early exposure to GC is essential to prevent fractures.