TY -的T1高灵敏度心肌肌钙蛋白在阻塞性睡眠呼吸暂停:CPAP后调整分析变化限制在低浓度(adjACL)小变化JF -欧洲呼吸杂志》乔和J - 10.1183/13993003.03022 -2021欧元SP - 2103022 AU Monneret丹尼斯Y1 - 2021/01/01 UR - //www.qdcxjkg.com/content/early/2021/12/16/13993003.03022 - 2021. -抽象N2 -甚至在第99个百分位参考上限(99潺潺流水),高灵敏度升高(hs-cTn)是心肌肌钙蛋白浓度与心血管风险增加有关[1]。然而,肌钙蛋白浓度越低,越高的分析不精确[2]。目前还不清楚到什么程度的改变hs-cTn之间(Δhs-cTn)是重要的检测极限(LOD)和99年的潺潺流水。最近,他等人相比,通过最近的随机控制试验,8周的影响持续气道正压(CPAP)在受试者Δhs-cTnI严重阻塞性睡眠呼吸暂停(OSA)和高血压[3]。他们表现出显著变化比未经处理的对象(调整后的平均差−1.74 ng·l - 1;p = 0.006)。hs-cTnI减少的调整意味着从5.6到4.8 ng CPAP·l - 1(−14.3%)后,和从7.9增加到8.5 ng·l - 1(+ 7.6%),对照组。这些值高于1.2 ng的LOD·l - 1,但是已经接近极限的量化5 ng·l - 1 (hs-cTnI试剂盒3 p25、雅培、芝加哥,美国)。从诊断的角度来看,在个体规模,参考价值(RCV)概念假设改变两个系列之间的结果意义重大,如果大于每个结果的变化的总和。这些变化主要是分析(分析变异系数、脑血管意外)和生物(自身内在,CVi) [2]。 Considering two serial results, the RCV is equal to Z*[(CVa12+CVi12)+(CVa22+CVi22)]1/2, with Z=1.96 for a probability of change of 95%. Considering only analytical imprecision -which mainly depends on assay methods and analyzers- as the minimal unavoidable variation, and applying it to serial results, the adjusted analytical change limit (adjACL) is equal to ±1.96*[(CVa12)+(CVa22)]1/2 [4]. To test whether the Δhs-cTnI observed after 8 weeks of CPAP was greater than the adjACL of hs-cTnI, we used CVa for hs-cTnI concentrations ranging from 50 to 1 ng·L‒1 (mean imprecision profile), provided in the supplemental data from [2], and measured on an Architect Abbott analyser, as did Lui et al. [3]. The regression equation of the best-fit curve was CVa=3997+28.17/hs-cTnI (figure 1). Applying this formula on serial hs-cTnI means of 5.6 and 4.8 ng·L‒1 (before and after CPAP), the adjACL was ±26.2%. Hence, at such low concentrations, the Δhs-cTnI of −14.3% is within the adjACL, meaning that the effect of CPAP is not great enough to decrease troponin more than analytical variability. According to this model, a decrease from 5.6 to at least 4.0 ng·L‒1 (Δhs-cTnI≤−28.6%, i.e., out of adjACL ±28.0%) would have been considered as significantly due to CPAP, at least in part. As expected, Δhs-cTnI of the control group (7.9 to 8.5 ng·L‒1, +7.6%) remains within the adjACL, calculated at ±20.6%. As demonstrated, the closer the concentrations are to the LOD, the greater the imprecision. This regression model reflects real analytical imprecisions for low ranges of hs-cTnI in the laboratory, with concentrations of 10%CV and 20%CV at 4.7 and 1.8 ng·L‒1 [5]. Another analytical consideration is lot-to-lot bias between hs-cTnI reagents and/or calibrators, which can occur over weeks and could partly bias the mean difference of −1.74 ng·L‒1 observed by Lui et al. Illustrating this, Wu et al. recently showed for Abbott hs-cTnI a lot-to-lot bias at low ranges (below 5.4 ng·L‒1) between −1.7 to +2.3 ng·L‒1 [6]. A large difference of 2.5 ng·L‒1 between two successive lots was even observed (from 4.7 to 7.2 ng·L‒1), leading the authors to conclude that “a total analytic error <3.5 ng·L‒1 for long-term studies with hs-cTnI concentrations <10 ng·L‒1 could prevent erroneous reporting of results” [7]. This bias is advantageously considered in the adjACL, since it is also determined over the course of weeks.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Denis Monneret has nothing to disclose. ER -