Capozza Ricardo F, Cure-Cure Carlos, Cointry Gustavo R, Meta Margarita, Cure Pablo, Rittweger Joern, Ferretti José Luis
Center of Ca-P Metabolism Studies, CEMFoC, National University of Rosario, Rosario, Argentina.
Menopause. 2008 Sep-Oct;15(5):905-13. doi: 10.1097/gme.0b013e318164ee85.
This study evaluated dual-energy x-ray absorptiometry-assessed whole-body bone-muscle relationship (bone mineral content/lean mass [BMC/LM]) as an indicator of its nonmechanical perturbations (ie, systemic) in pre- and postmenopausal women. A total of 3,205 women were studied, either healthy (no fracture [No Fx] groups, 1,035 premenopausal, 1,556 postmenopausal) or with recent fractures (Fx groups, 139 premenopausal, 475 postmenopausal) located at osteoporotic sites (hip, spine, long-bone metaphyses; Type II Fx, n = 386) or at other skeletal sites (Type I Fx, n = 228) to evaluate the impact of decreased muscle mass on fracture incidence before and after menopause.
SD-scored graphs of BMC/LM proportionality were obtained from the No Fx groups as normal references. Based on the reference BMC versus LM curves obtained from their respective No Fx pre- and postmenopausal controls, BMC-LM SD scores were calculated for all women with fractures.
BMC-LM SD scores in all premenopausal women with fractures and in Type I Fx postmenopausal women were similar to the reference. In contrast, SD scores in Type II Fx postmenopausal women were lower than the reference, especially in those with hip fractures. Except for Type II Fx postmenopausal women, all groups showed linear and similar BMC versus LM curves. Type II Fx postmenopausal women showed nonlinear relationships, with progressively decreasing BMC and BMC-LM SD scores as their LM decreased.
Results suggest that both LM and BMC-LM SD scores can help to differentiate between systemic and mechanical (disuse-related) osteopenia/osteoporosis after menopause. Low LM values or BMC-LM SD scores seem to constitute additional fracture risk factors beyond those usually detected in premenopausal women or in women with other types of fractures. This application of dual-energy x-ray absorptiometry technology may lead to more effective diagnosis and treatment at low cost.
本研究评估了双能X线吸收法测定的全身骨-肌肉关系（骨矿物质含量/瘦体重[BMC/LM]），以此作为绝经前和绝经后女性非机械性扰动（即全身性）的一个指标。共对3205名女性进行了研究，她们要么健康（无骨折[无Fx]组，1035名绝经前女性，1556名绝经后女性），要么近期在骨质疏松部位（髋部、脊柱、长骨干骺端；II型骨折，n = 386）或其他骨骼部位（I型骨折，n = 228）发生骨折（Fx组，139名绝经前女性，475名绝经后女性），以评估绝经前后肌肉量减少对骨折发生率的影响。
从无Fx组获取BMC/LM比例的标准差评分图作为正常参考。根据从各自绝经前和绝经后无Fx对照获得的参考BMC与LM曲线，为所有骨折女性计算BMC-LM标准差评分。
所有绝经前骨折女性和I型骨折绝经后女性的BMC-LM标准差评分与参考值相似。相比之下，II型骨折绝经后女性的标准差评分低于参考值，尤其是髋部骨折女性。除II型骨折绝经后女性外，所有组的BMC与LM曲线均呈线性且相似。II型骨折绝经后女性表现出非线性关系，随着瘦体重降低，BMC和BMC-LM标准差评分逐渐下降。
结果表明，瘦体重和BMC-LM标准差评分均有助于区分绝经后的全身性和机械性（废用相关）骨质减少/骨质疏松。低瘦体重值或BMC-LM标准差评分似乎构成了绝经前女性或其他类型骨折女性中通常检测到的骨折风险因素之外的额外骨折风险因素。双能X线吸收法技术的这种应用可能会以低成本实现更有效的诊断和治疗。
