Cost-Minimization Study Comparing Annual Infusion of Zoledronic Acid or Weekly Oral Alendronate in Women With Low Bone Mineral Density

Abstract

Cost-minimization study to assess the annual direct costs of 2 antiresorptive strategies in postmenopausal women with low bone mineral densities (BMDs). Patients were randomly assigned to receive 70mg of oral weekly alendronate or a 1-time 5mg of intravenous zoledronic acid. All medical and nonmedical direct costs were recorded for 1yr. Student's t-test or the Chi-squared test was used. A total of 101 postmenopausal women were enrolled with a mean age of 58.3±7.6yr and a postmenopausal period of 13.5±8.3yr. A total of 50 patients completed 1yr of alendronate and 51 patients received zoledronic acid. At baseline, no differences were seen between the 2 groups in anthropometric measures, comorbidities, and bone mineral density. The costs for medical attention for low bone mass were $81,532 (US Dollars) for the alendronate group and $69,251 for the zoledronic acid group; the cost per patient was $1631 in the alendronate group vs $1358 in the zoledronic acid group (p<0.0001). Therefore, zoledronic acid treatment provided an annual savings of 15% of the direct costs compared with oral alendronate treatment. Moreover, there was a significant increase in lumbar spine T-scores in the zoledronic acid group when compared with the alendronate group. Annual zoledronic acid infusion as an antiresorptive treatment in women with low BMD provides significant monetary savings when compared with weekly alendronate therapy for 1yr. Zoledronic acid infusion is also linked to higher increase in BMD and compliance.