Department of Clinical Biochemistry, Hospital Universitario Miguel Servet, Zaragoza, Spain.
Department of Clinical Biochemistry, Hospital del Oriente de Asturias, Arriondas, Asturias, Spain.
Biochem Med (Zagreb). 2021 Feb 15;31(1):010701. doi: 10.11613/BM.2021.010701. Epub 2020 Dec 15.
The accurate estimation of low-density lipoprotein cholesterol (LDL) is crucial for management of patients at risk of cardiovascular events due to dyslipidemia. The LDL is typically calculated using the Friedewald equation and/or direct homogeneous assays. However, both methods have their own limitations, so other equations have been proposed, including a new equation developed by Sampson. The aim of this study was to evaluate Sampson equation by comparing with the Friedewald and Martin-Hopkins equations, and with a direct LDL method.
Results of standard lipid profile (total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL) and triglycerides (TG)) were obtained from two anonymized data sets collected at two laboratories, using assays from different manufacturers (Beckman Coulter and Roche Diagnostics). The second data set also included LDL results from a direct assay (Roche Diagnostics). Passing-Bablok and Bland-Altman analysis for method comparison was performed.
A total of 64,345 and 37,783 results for CHOL, HDL and TG were used, including 3116 results from the direct LDL assay. The Sampson and Friedewald equations provided similar LDL results (difference ≤ 0.06 mmol/L, on average) at TG ≤ 2.0 mmol/L. At TG between 2.0 and 4.5 mmol/L, the Sampson-calculated LDL showed a constant bias (- 0.18 mmol/L) when compared with the Martin-Hopkins equation. Similarly, at TG between 4.5 and 9.0 mmol/L, the Sampson equation showed a negative bias when compared with the direct assay, which was proportional (- 16%) to the LDL concentration.
The Sampson equation may represent a cost-efficient alternative for calculating LDL in clinical laboratories.
准确估计低密度脂蛋白胆固醇（LDL）对于因血脂异常而有心血管事件风险的患者的管理至关重要。LDL 通常使用 Friedewald 方程和/或直接均相测定法来计算。然而，这两种方法都有其自身的局限性，因此提出了其他方程，包括 Sampson 提出的新方程。本研究旨在通过与 Friedewald 和 Martin-Hopkins 方程以及直接 LDL 方法进行比较，来评估 Sampson 方程。
从两个匿名数据集中获得了标准血脂谱（总胆固醇（CHOL）、高密度脂蛋白胆固醇（HDL）和甘油三酯（TG））的结果，这些数据是在两个实验室使用来自不同制造商（贝克曼库尔特和罗氏诊断公司）的测定法收集的。第二个数据集还包括直接测定法（罗氏诊断公司）的 LDL 结果。对方法比较进行了 Passing-Bablok 和 Bland-Altman 分析。
共使用了 64345 次 CHOL、HDL 和 TG 结果和 3116 次直接 LDL 测定法的结果。在 TG≤2.0mmol/L 时，Sampson 和 Friedewald 方程提供了相似的 LDL 结果（差异≤0.06mmol/L，平均）。在 TG 为 2.0 至 4.5mmol/L 之间，与 Martin-Hopkins 方程相比，Sampson 计算的 LDL 显示出恒定的偏差（-0.18mmol/L）。同样，在 TG 为 4.5 至 9.0mmol/L 之间，与直接测定法相比，Sampson 方程显示出负偏差，该偏差与 LDL 浓度成比例（-16%）。
Sampson 方程可能是临床实验室计算 LDL 的一种具有成本效益的替代方法。
