title: The importance of absolute bone mineral density in the assessment of antiresorptive agents used for the prevention of osteoporotic fractures.
abstract: The usefulness of bone mineral density (BMD) monitoring during antiresorptive treatment is still controversial. This study aimed to determine which factors of change (absolute value or the percent change from the baseline) in BMD are associated with the risk of future fractures. A total of 565 postmenopausal osteoporosis who were treated antiresorptive drugs were included in this prospective observational study. Lumbar BMD (LBMD) was measured at baseline and 1-yr after the initial and subsequent incident fracture was observed. The percent changes in LBMD at 1 yr were 5.4 ± 6.4% and 118 (20.9%) achieved increased LBMD with change of classification to >-2.5 standard deviation (SD). After the initial 1-yr examination, incident fractures developed in 152 (26.9%). The incident fracture risk was significantly associated with the absolute value in LBMD, but not with the percent change. A Cox proportional hazard model demonstrated that increased LBMD with change of classification to >-2.5 SD was a significant predictor for a reduction in incident fractures (hazard ratio: 0.41, 95% confidence interval: 0.21-0.71). In conclusion, these results suggest that monitoring of the antifracture efficacy of antiresorptive treatments should be based on the absolute value of BMD. In particular, increased change to >-2.5 SD is important for reducing the future fracture risk.
authors.affiliation: Public Health Research Foundation, Tokyo, Japan.
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kuroda
authors.affiliation: Department of Internal Medicine, Research Institute and Practice for Involutional Diseases, Nagano, Japan. Electronic address: ripid@fc4.so-net.ne.jp.
authors.forename: Masataka
authors.initials: M
authors.lastname: Shiraki
authors.affiliation: Department of Internal Medicine, Research Institute and Practice for Involutional Diseases, Nagano, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Shiraki
authors.affiliation: Division of Clinical Trial Design and Management, Translational Research Center, Kyoto University, Kyoto, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Tanaka
mesh_terms: D000368:Aged; D015519:Bone Density; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008159:Lumbar Vertebrae / Q000293:injuries*; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D016103:Spinal Fractures / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*
chemical_list: D050071:Bone Density Conservation Agents