Comparison of Alendronate and Intranasal Calcitonin for Treatment of Osteoporosis in Postmenopausal Women

Abstract

Both alendronate and calcitonin, the latter administered intranasally, reportedly increase bone mineral density (BMD) and reduce bone turnover, but alendronate seems to be somewhat more effective. This study directly and prospectively compared these treatments in 299 women with an average age of 64 years who were at least 5 years postmenopausal. BMD was monitored at the lumbar spine and femoral neck and trochanter by dual-energy x-ray absorptiometry during 12 months of treatment with 10 mg of alendronate, a matching placebo, or open-label intranasal calcitonin in a daily dose of 200 IU. Serum bone-specific alkaline phosphatase (BSAP) and urinary N-telopeptide of type I collagen adjusted for urinary creatinine (NTx) were measured as markers of bone formation and resorption, respectively. BMD at both the lumbar spine and trochanter increased significantly more in patients given alendronate than in those given calcitonin (Fig. 1). The effect of alendronate significantly exceeded that in placebo patients at all sites. Both serum BSAP and urinary NTx decreased substantially more in alendronate-treated patients than in those given calcitonin or placebo at all intervals (Fig. 2). Adverse events in general and serious complications were noted in similar proportions of all groups. Effects on the upper gastrointestinal tract were more prevalent with alendronate therapy than with calcitonin therapy but were nearly as frequent in patients given the alendronate placebo. Findings in this double-blind randomized study indicate that alendronate was more effective than intranasal calcitonin in promoting increased BMD in postmenopausal women. It suppressed bone turnover more than did calcitonin during 1 year of treatment.Fig. 1: BMD. Mean percent change (±SE) in BMD of the lumbar spine, hip trochanter, and femoral neck with 10 mg of alendronate (ALN, ○), 200 IU of intranasal calcitonin (CT, ▵), and placebo tablet (PBO, □) over 12 months. P values for between-group comparisons are presented.Fig. 2: Biochemical markers of bone turnover. Mean percent change from baseline and SE in BSAP and NTx with 10 mg of alendronate (ALN, ○), 200 IU of intranasal calcitonin (CT, ▵), and placebo tablet (PBO, □) over 12 months. P values for between-group comparisons are presented.J Clin Endocrinol Metab 2000;85:1783–1788