Department of Renal Medicine, Aarhus University Hospital, Aarhus, Denmark.
Department of Renal Medicine, Aarhus University Hospital, Aarhus, Denmark; Department of Renal Medicine, Copenhagen University Hospital, Copenhagen, Denmark.
Transplant Proc. 2023 Nov;55(9):2071-2078. doi: 10.1016/j.transproceed.2023.08.025. Epub 2023 Oct 6.
Reliable estimates of glomerular filtration rate (eGFR) are important for detecting changes in graft function in kidney transplant recipients. Current eGFR equations are based on plasma creatinine and/or cystatin C; however, these are associated with significant bias. This study investigated if equations based on β-trace protein (BTP) and β2-microglobulin (B2M) performed better than the 2021 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations based on creatinine and cystatin C among kidney transplant recipients.
We included samples and data from the clinical trial CONTEXT. Glomerular filtration rate (GFR) was measured by plasma clearance of an exogenous marker. The eGFR was calculated using the CKD-EPI equations for estimating GFR from BTP and/or B2M and the 2021 CKD-EPI creatinine and creatinine-cystatin C equations. The GFR estimates were evaluated 3 (n = 82) and 12 (n = 64) months after transplant using mean bias, precision, and accuracy. Furthermore, we analyzed the ability of the equations to correctly classify the direction of changes in measured GFR from 3 to 12 months.
Among the BTP- and B2M-based equations, the combined eGFR-BTP-B2M performed best with respect to precision (SD = 7.64 mL/min/1.73 m) and accuracy (±10% from measured GFR = 36%). The eGFR-BTP-B2M and the eGFR-creatinine-cystatin C (2021) performed similarly when comparing precision, accuracy, and residuals (P = .481). The BTP- and/or B2M-based equations did not perform better than the eGFR-creatinine-cystatin C (2021) in correctly classifying the direction of changes in measured GFR from 3 to 12 months.
β-trace protein and/or B2M do not improve the estimation of GFR when compared with creatinine- and cystatin C-based 2021 CKD-EPI equations.
对于检测肾移植受者移植物功能的变化，可靠的肾小球滤过率 (eGFR) 估计值非常重要。目前的 eGFR 方程基于血浆肌酐和/或胱抑素 C；然而，这些与显著的偏差有关。本研究探讨了基于β-痕迹蛋白 (BTP) 和β2-微球蛋白 (B2M) 的方程在肾移植受者中是否比基于肌酐和胱抑素 C 的 2021 年慢性肾脏病流行病学合作 (CKD-EPI) 方程表现更好。
我们纳入了临床试验 CONTEXT 的样本和数据。通过外源性标记物的血浆清除率来测量肾小球滤过率 (GFR)。使用 CKD-EPI 方程计算基于 BTP 和/或 B2M 的 eGFR，以及 2021 年 CKD-EPI 肌酐和肌酐-胱抑素 C 方程。使用平均偏差、精密度和准确性评估移植后 3（n=82）和 12 个月（n=64）的 GFR 估计值。此外，我们分析了这些方程正确分类 3 至 12 个月期间测量的 GFR 变化方向的能力。
在基于 BTP 和 B2M 的方程中，组合 eGFR-BTP-B2M 表现最好，精密度（SD=7.64 mL/min/1.73 m）和准确性（与测量的 GFR 相差±10%=36%）。eGFR-BTP-B2M 和 eGFR-肌酐-胱抑素 C（2021）在比较精密度、准确性和残差时表现相似（P=0.481）。与 eGFR-肌酐-胱抑素 C（2021）相比，基于 BTP 和/或 B2M 的方程在正确分类 3 至 12 个月期间测量的 GFR 变化方向方面并没有表现更好。
与基于肌酐和胱抑素 C 的 2021 年 CKD-EPI 方程相比，β-痕迹蛋白和/或 B2M 并不能改善 GFR 的估计。
