NIHR Musculoskeletal Biomedical Research Unit, Department of Human Metabolism, University of Sheffield, Sheffield, UK.
Osteoporos Int. 2013 Mar;24(3):941-7. doi: 10.1007/s00198-012-2097-4. Epub 2012 Aug 8.
We measured urinary N-telopeptide of type I collagen (U-NTX) to monitor response to bisphosphonates for osteoporosis. Decrease in U-NTX was associated with increase in spine bone density. A lesser response in U-NTX was more likely in those with secondary osteoporosis or with poor compliance. U-NTX may be a useful early indicator of treatment non-compliance or secondary osteoporosis.
This study aims to determine the utility of the bone resorption marker, U-NTX, in the clinical setting, to monitor the response to bisphosphonate therapy (alendronate and risedronate) for osteoporosis.
A retrospective evaluation of data collected as part of the bone turnover marker monitoring service in the Metabolic Bone Centre, Sheffield, UK. Treatment compliance, underlying causes of osteoporosis, change in U-NTX/creatinine (Cr) at 4 months and change in spine and hip bone mineral density (BMD) by dual-energy X-ray absorptiometry were recorded. Treatment response was defined as either a change in U-NTX/Cr greater than a pre-defined least significant change (LSC) of 54 % or to within the lower half of a pre-defined pre-menopausal reference interval (≤ 30 nM BCE/mmol Cr).
A greater decrease in U-NTX/Cr at 4 months was associated with a greater increase in spine BMD at 18 months (r = -0.33; P < 0.0001, Pearson's correlation). The mean U-NTX/Cr at 4 months was higher in patients with secondary osteoporosis compared with those with primary osteoporosis (P < 0.01, ANOVA). A lesser response in U-NTX/Cr increased the likelihood of secondary osteoporosis or poor treatment compliance (P = 0.04, Fisher's exact test). A lack of response in U-NTX/Cr to within the lower half of the reference interval was a better indicator of secondary osteoporosis and treatment non-compliance than a change in U-NTX/Cr greater than LSC.
Treatment monitoring using U-NTX/Cr has a place in clinical practice for the early identification of non-compliance or presence of secondary osteoporosis.
我们测量了尿Ⅰ型胶原 N 端肽（U-NTX）以监测骨质疏松症的双膦酸盐反应。U-NTX 的减少与脊柱骨密度的增加有关。U-NTX 反应较差的患者更可能患有继发性骨质疏松症或治疗依从性差。U-NTX 可能是治疗不依从或继发性骨质疏松症的早期有用指标。
本研究旨在确定骨吸收标志物 U-NTX 在临床环境中的效用，以监测双膦酸盐（阿仑膦酸钠和利塞膦酸钠）治疗骨质疏松症的反应。
对英国谢菲尔德代谢性骨中心骨转换标志物监测服务中收集的数据进行回顾性评估。记录了治疗依从性、骨质疏松症的潜在原因、4 个月时 U-NTX/肌酐（Cr）的变化以及双能 X 线吸收法测量的脊柱和髋部骨矿物质密度（BMD）的变化。治疗反应定义为 U-NTX/Cr 的变化大于预先定义的最小显著变化（LSC）54%或在预先定义的绝经前参考区间的下半部分（≤30 nM BCE/mmol Cr）内。
4 个月时 U-NTX/Cr 的下降幅度与 18 个月时脊柱 BMD 的增加幅度呈正相关（r = -0.33；P <0.0001，Pearson 相关）。与原发性骨质疏松症患者相比，继发性骨质疏松症患者 4 个月时 U-NTX/Cr 平均值更高（P <0.01，方差分析）。U-NTX/Cr 反应较差会增加继发性骨质疏松症或治疗依从性差的可能性（P = 0.04，Fisher 精确检验）。U-NTX/Cr 未能达到参考区间的下半部分是继发性骨质疏松症和治疗不依从的更好指标，而 U-NTX/Cr 的变化大于 LSC 则不是。
使用 U-NTX/Cr 进行治疗监测在临床实践中有一定的地位，可早期识别不依从或存在继发性骨质疏松症。
