Kim Sang Wan, Park Do Joon, Park Kyong Soo, Kim Seong Yeon, Cho Bo Youn, Lee Hong Kyu, Shin Chan Soo
Department of Internal Medicine, Seoul National University College of Medicine, Seoul.
Endocr J. 2005 Dec;52(6):667-74. doi: 10.1507/endocrj.52.667.
Biochemical markers of bone turnover have been suggested to be useful in monitoring the efficacy of antiresorptive therapy. In this study, we investigated the predictive value of bone turnover markers to determine short-term response in bone mineral density (BMD) and to identify nonresponders in 138 postmenopausal women (mean age 58 years) with osteoporosis given with either hormone thearpy (HT) or alendronate. Urinary type I collagen N-telopeptide (NTx) and serum osteocalcin (OC) at baseline, 3, and 6 months after treatment as well as spine and femoral neck BMD at baseline and 12 months were measured. Significant decreases in both NTx and OC were evident in women on treatment with antiresorptive agents as early as 3 months (p<0.01). Percent change of NTx at 3 months correlated with the percent change of spinal BMD at 12 months of treatment. When bone turnover markers were stratified by tertiles, the average rate of lumbar spine BMD gain increased significantly with increasing tertiles of baseline value (p<0.05) and percent change (p<0.05) of urinary NTx at 3 month of treatment. In terms of BMD response, urinary NTx at 3 months decreased significantly more in BMD responders group than in nonresponders group. Logistic regression analysis demonstrated that percent change of NTx at 3 months is an independent predictor to identify BMD nonresponders, defined as those whose BMD gain remained within the precision error range of dual energy X-ray absorptiometer (DXA). We conclude that biochemical markers of bone turnover, especially percent change in urinary NTx levels, can be used to determine BMD response to antiresorptive therapy in Korean postmenopausal women with osteoporosis.
骨转换生化标志物已被认为有助于监测抗吸收治疗的疗效。在本研究中，我们调查了骨转换标志物在确定骨矿物质密度（BMD）短期反应以及识别138名接受激素治疗（HT）或阿仑膦酸盐治疗的绝经后骨质疏松症女性（平均年龄58岁）中的无反应者方面的预测价值。测量了基线、治疗后3个月和6个月时的尿I型胶原N-端肽（NTx）和血清骨钙素（OC），以及基线和12个月时的脊柱和股骨颈BMD。接受抗吸收药物治疗的女性在治疗3个月时，NTx和OC均显著下降（p<0.01）。治疗3个月时NTx的变化百分比与治疗12个月时脊柱BMD的变化百分比相关。当根据三分位数对骨转换标志物进行分层时，腰椎BMD增加的平均速率随着治疗3个月时尿NTx基线值（p<0.05）和变化百分比（p<0.05）的三分位数增加而显著增加。就BMD反应而言，BMD反应者组治疗3个月时尿NTx的下降幅度显著大于无反应者组。逻辑回归分析表明，治疗3个月时NTx的变化百分比是识别BMD无反应者的独立预测指标，BMD无反应者定义为其BMD增加保持在双能X线吸收仪（DXA）精度误差范围内的人群。我们得出结论，骨转换生化标志物，尤其是尿NTx水平的变化百分比，可用于确定韩国绝经后骨质疏松症女性对抗吸收治疗的BMD反应。
