Efficacy of zoledronic acid in treatment of osteoporosis in men and women-a meta-analysis

Abstract

Background: Osteoporosis is a significant cause of morbidity and mortality in the elderly and an important public health issue. Bisphosphonates are the primary treatment options for osteoporosis. The oral administration of bisphosphonates may result in poor patient compliance and thence reduced treatment efficacy. Intravenously administered bisphosphonates may therefore show better treatment efficacy. We have carried out a meta-analysis to evaluate the efficacy of zoledronic acid treatment for osteoporosis in both men and women with either vertebral or non-vertebral fracture.

Material and methods: Randomized controlled trials with zoledronic acid treatment for osteoporosis were retrieved from PubMed, EMBASE and clinicaltrials.gov. The risk ratio with 95% confidence interval (RR, 95% CI) was calculated to evaluate the effect of zoledronic acid treatment on incidence of fracture. Data on changes in bone mineral density (BMD) following zoledronic acid (ZOL) treatment was also extracted. STATA software was used for all the statistical analyses.

Results: Significant reduction in the incidence of both vertebral and nonvertebral fracture was observed following ZOL treatment, as seen from the values for RR with 95% CI (RR 0.24 and 95% CI 0.15 to 0.40 for vertebral fractures; RR 0.76 and 95% CI 0.67 to 0.86 for nonvertebral fractures). BMD was also seen to be increased after ZOL treatment.

Conclusion: Ourmeta-analysis showed that zoledronic acid was effective in reducing the incidence of vertebral fractures as well as nonvertebral fractures, including hip fractures. Significant increase in bone mineral density (BMD) was also observed in patients administered ZOL as compared to placebo.

Keywords: Bisphosphonates; bone mineral density; hip fracture; osteoporosis.

Figures

Figure 1

Prisma Flow chart depicting selection and retrieval of studies for meta-analysis.

Figure 2

Effect of zoledronic acid on incidence of vertebral fractures.Pooled estimate for the risk of vertebral fractures shows that zoledronic acid reduces the risk of vertebral fractures. Heterogeneity chi-squared = 7.43 (d. f. = 2) P = 0.024. Estimate between-study variance Tau-squared = 0.1322; Test of RR = 1: z = 5.63 P = 0.000.

Figure 3

Effect of zoledronic acid on incidence of nonvertebral fractures.Pooled estimate for the risk of nonvertebral fractures showing a reduction in vertebral fractures with zoledronic acid.Heterogeneity chi-squared = 0.03 (d.f. = 1) P = 0.864; Test of RR = 1: z = 4.31 P = 0.000.

Figure 4

Effect of zoledronic acid on incidence of hip fractures. Pooled estimate for the risk of hip fractures shows that zoledronic acid reduces the risk of vertebral fractures. Heterogeneity chi-squared = 0.29 (d. f. = 1) P = 0.591; Test of RR = 1: z = 3.29 P = 0.001.