title: The response in spinal bone mass to tibolone treatment is related to bone turnover in elderly women.
abstract: To determine the ability of bone turnover to predict the response in bone mass during treatment with Tibolone, two biochemical markers of bone metabolism were evaluated [CrossLaps corrected for urinary creatinine (CrossLaps/Cr.) and serum osteocalcin measured in a newly developed assay (N-Mid)]. Data from a 2-year double-blind, randomized trial with 56 completing Tibolone-treated women and 13 placebo-treated women were studied. Bone mineral density in the spine (QDR-1000) and indices of bone turnover were determined every 3 months throughout the study. The response in bone mass was calculated as the percent annual change in bone mineral density from baseline and was determined from a total of nine measurements. The response in bone mass was correlated to prestudy values of CrossLaps/Cr. (r = 0.27; p < 0.05), but was uncorrelated to prestudy values of N-Mid. The changes from baseline of these two markers were significantly correlated with the response in bone mass from the 6 months' time point and throughout the rest of the study, i.e., at 1 year: CrossLaps/Cr.: r = 0.54; p < 0.001, N-Mid: r = 0.49; p < 0.001). The change from baseline in the two markers was clearly more predictive of the response in bone mass than the baseline values of these markers as evaluated in a multiple, linear regression-model. Within 1 year of Tibolone-treatment, measured changes in CrossLaps/Cr. and bone mineral density are at least equally predictive of the true response in bone mass over 2 years. These results indicate a possibility of monitoring Tibolone therapy with biochemical markers of bone turnover, at least on group basis.
authors.affiliation: Center for Clinical and Basic Research, Ballerup, Denmark.
authors.forename: N H
authors.initials: NH
authors.lastname: Bjarnason
authors.forename: K
authors.initials: K
authors.lastname: Bjarnason
authors.forename: C
authors.initials: C
authors.lastname: Hassager
authors.forename: C
authors.initials: C
authors.lastname: Christiansen
mesh_terms: D000368:Aged; D045930:Anabolic Agents / Q000627:therapeutic use*; D015519:Bone Density / Q000187:drug effects*; D016723:Bone Remodeling / Q000502:physiology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D016014:Linear Models; D009652:Norpregnenes / Q000627:therapeutic use*; D011379:Prognosis
chemical_list: D045930:Anabolic Agents; D009652:Norpregnenes; C027385:tibolone