Gossiel F, Ugur A, Peel N F A, Walsh J S, Eastell R
Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK.
The Medical School, Beech Hill Road, Sheffield, S10 2RX, UK.
Osteoporos Int. 2022 Jun;33(6):1357-1363. doi: 10.1007/s00198-022-06311-3. Epub 2022 Jan 31.
TRACP-5b can be used to monitor the response of treatments in osteoporosis. We investigated the effect of feeding on levels of TRACP-5b and how these markers perform in a clinical setting. After feeding, there was no effect on levels TRACP-5b. It has similar diagnostic accuracy to CTX and PINP.
Bone turnover markers (BTMs) can be used to monitor response to osteoporosis treatment. However, some are affected by food intake and are not suitable to measure in a clinical setting. An assay is available which is capable of detecting the active isoform 5b of tartrate resistance acid phosphatase (TRACP-5b) and it may have minimal biological variation. Our aims were to investigate the effect of feeding on levels of TRACP-5b and compare this to CTX and PINP and then to compare the diagnostic accuracy of TRACP-5b to CTX and PINP in patients with osteoporosis given commonly used treatments.
Eighteen patients were recruited to investigate the effect of feeding on BTMs. Ninety-seven patients (74 females and 23 males) receiving 5 mg annual intra-venous zoledronate (mean age 70) and 97 patients receiving no treatment were recruited as group-matched controls. Sixteen patients receiving 60 mg subcutaneous denosumab every 6 months, (mean age 76) and 16 matched controls were recruited. Seventy-six patients were receiving oral bisphosphonates: 70 mg alendronate weekly, 35 mg risedronate and 150 mg monthly ibandronate (4%). Thirty of these patients had BMD measured at the total hip and lumbar spine. An estimate of compliance was not determined. Eighty patients receiving no treatment were recruited as group-matched controls. TRACP-5b (ELISA, Nittobo) and CTX and PINP were measured in serum in the non-fasting state between 0800 and 1700.
After feeding, there was no effect on levels TRACP-5b and significant reductions in CTX and PINP, 29% and 10%, respectively (p < 0.001). In the zoledronate and denosumab groups, there were no differences in the areas under the curves (AUCs) between TRACP-5b, PINP and CTX. In the oral bisphosphonates group, the AUCs between TRACP-5b and PINP and TRACP-5b and CTX were significantly different, p < 0.01 and p = 0.001, respectively. TRACP-5b was negatively correlated with BMD.
TRACP-5b is not affected by food intake, unlike CTX and PINP. All three BTMs correlate with change in BMD at the lumbar spine and total hip. TRACP-5b has similar diagnostic accuracy to CTX and PINP with commonly used treatments for osteoporosis with the exception of oral bisphosphonate therapy.
抗酒石酸酸性磷酸酶5b（TRACP-5b）可用于监测骨质疏松症治疗的反应。我们研究了进食对TRACP-5b水平的影响以及这些标志物在临床环境中的表现。进食后，对TRACP-5b水平没有影响。它与I型胶原交联C端肽（CTX）和I型前胶原氨基端前肽（PINP）具有相似的诊断准确性。
骨转换标志物（BTMs）可用于监测骨质疏松症治疗的反应。然而，有些会受到食物摄入的影响，不适合在临床环境中测量。有一种检测方法能够检测抗酒石酸酸性磷酸酶的活性同工型5b（TRACP-5b），并且它可能具有最小的生物学变异。我们的目的是研究进食对TRACP-5b水平的影响，并将其与CTX和PINP进行比较，然后比较TRACP-5b与CTX和PINP在接受常用治疗的骨质疏松症患者中的诊断准确性。
招募了18名患者来研究进食对BTMs的影响。97名接受每年5毫克静脉注射唑来膦酸的患者（74名女性和23名男性，平均年龄70岁）和97名未接受治疗的患者作为组匹配对照被招募。16名每6个月接受60毫克皮下注射地诺单抗的患者（平均年龄76岁）和16名匹配对照被招募。76名患者正在接受口服双膦酸盐治疗：每周70毫克阿仑膦酸钠、35毫克利塞膦酸钠和每月150毫克伊班膦酸钠（4%）。这些患者中有30名在全髋和腰椎进行了骨密度测量。未确定依从性的估计值。80名未接受治疗的患者作为组匹配对照被招募。在08:00至17:00的非空腹状态下，在血清中测量TRACP-5b（酶联免疫吸附测定法，日东纺）以及CTX和PINP。
进食后，对TRACP-5b水平没有影响，而CTX和PINP分别显著降低了29%和10%（p < 0.001）。在唑来膦酸和地诺单抗组中，TRACP-5b、PINP和CTX之间的曲线下面积（AUCs）没有差异。在口服双膦酸盐组中，TRACP-5b与PINP之间以及TRACP-5b与CTX之间的AUCs分别有显著差异，p < 0.01和p = 0.001。TRACP-5b与骨密度呈负相关。
与CTX和PINP不同，TRACP-5b不受食物摄入的影响。所有三种BTMs都与腰椎和全髋骨密度的变化相关。除口服双膦酸盐治疗外，TRACP-5b在骨质疏松症的常用治疗中与CTX和PINP具有相似的诊断准确性。
