Comparison of biochemical markers of bone remodelling in the assessment ofthe effects of alendronate on bone in postmenopausal osteoporosis

The effects of alendronate treatment on biochemical markers of bone remodel ling and bone mineral density (BMD) were studied in 30 Caucasian women (pos tmenopausal for at least 3 years, age 42-76 years, with BMD of the lumbar s pine at least 2 S.D. below the mean for mature, premenopausal women). The p atients were randomly assigned to receive alendronate (10 mg/day) or placeb o for 12 months (double blind). The study was subsequently extended to a se cond year of open alendronate treatment. The treatment with alendronate res ulted in a significant and progressive increase in BMD of the lumbar spine and femoral neck. Under the treatment, the maximal decrease of biochemical markers of bone remodelling (osteocalcin in plasma, bone-specific alkaline phosphatase, N-terminal propeptide of type I procollagen and C-terminal tel opeptide of type I collagen in serum, and cross-linked amino-terminal N-tel opeptide and total hydroxyproline in urine) was observed at 6 months with n o further change during the 2-year period. There were no significant differ ences in discriminating between patients treated for 1 year with alendronat e or placebo using either the percentage change in spine BMD at month 12, o r a single measurement of the marker at month 6, or log (percent of baselin e at month 6 of value of the marker). In this respect, the power of all the biochemical markers were comparable. The markers are a valuable adjunct to the measurements of BMD, especially in the patients not showing an increas e of 3% or more at the lumbar spine BMD after 1 year of treatment. (C) 1999 Elsevier Science B.V. All rights reserved.