Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia.
Attoquant Diagnostics GmbH, Vienna, Austria.
Clin Chem. 2020 Mar 1;66(3):483-492. doi: 10.1093/clinchem/hvaa001.
Many medications (including most antihypertensives) and physiological factors affect the aldosterone/renin ratio (ARR) when screening for primary aldosteronism (PA). We sought to validate a novel equilibrium angiotensin II (eqAngII) assay and compare correlations between the aldosterone/angiotensin II ratio (AA2R) and the current ARR under conditions affecting the renin-angiotensin system.
Among 78 patients recruited, PA was excluded in 22 and confirmed in 56 by fludrocortisone suppression testing (FST). Peripheral levels of eqAngII, plasma renin activity (PRA) and direct renin concentration (DRC) were measured.
EqAngII showed good consistency with DRC and PRA independent of PA diagnosis, posture, and fludrocortisone administration. EqAngII showed close (P < 0.01) correlations with DRC (r = 0.691) and PRA (r = 0.754) during FST. DRC and PRA were below their assays' functional sensitivity in 43.9% and 15.1%, respectively, of the total 312 samples compared with only 7.4% for eqAngII (P < 0.01). Bland-Altman analysis revealed an overestimation of PRA and DRC compared with eqAngII in a subset of samples with low renin levels. The AA2R showed not only consistent changes with the ARR but also close (P < 0.01) correlations with the ARR, whether renin was measured by DRC (r = 0.878) or PRA (r = 0.880).
Dynamic changes of eqAngII and the AA2R show good consistency and close correlations with renin and the ARR. The eqAngII assay shows better sensitivity than DRC and PRA assays, especially at low concentrations. Whether the AA2R can reduce the impact of some factors that influence the diagnostic power of the ARR warrants further study.
在原发性醛固酮增多症（PA）筛查中，许多药物（包括大多数降压药）和生理因素都会影响醛固酮/肾素比值（ARR）。我们试图验证一种新的平衡血管紧张素 II（eqAngII）检测方法，并比较在影响肾素-血管紧张素系统的情况下，醛固酮/血管紧张素 II 比值（AA2R）与当前 ARR 的相关性。
在招募的 78 名患者中，22 名患者被排除在 PA 之外，56 名患者通过氟氢可的松抑制试验（FST）被确诊为 PA。测量外周 eqAngII、血浆肾素活性（PRA）和直接肾素浓度（DRC）水平。
eqAngII 与 DRC 和 PRA 具有良好的一致性，与 PA 诊断、体位和氟氢可的松给药无关。在 FST 期间，eqAngII 与 DRC（r=0.691）和 PRA（r=0.754）密切相关（P<0.01）。与 eqAngII 相比，DRC 和 PRA 在 312 个总样本中分别有 43.9%和 15.1%低于其检测的功能灵敏度，而 eqAngII 仅为 7.4%（P<0.01）。Bland-Altman 分析显示，与 eqAngII 相比，在一些肾素水平较低的样本中，PRA 和 DRC 的测量值存在高估。AA2R 不仅与 ARR 具有一致的变化，而且与 ARR 密切相关（P<0.01），无论是通过 DRC（r=0.878）还是 PRA（r=0.880）测量肾素。
eqAngII 和 AA2R 的动态变化与肾素和 ARR 具有良好的一致性和密切的相关性。eqAngII 检测法比 DRC 和 PRA 检测法具有更好的灵敏度，尤其是在低浓度时。AA2R 是否可以降低一些影响 ARR 诊断能力的因素的影响，需要进一步研究。
