Holvoet Paul, Macy Elizabeth, Landeloos Michele, Jones Dan, Jenny Nancy S, Van de Werf Frans, Tracy Russell P
Department of Cardiovascular Diseases, Katholieke Universiteit Leuven, Leuven, Belgium.
Clin Chem. 2006 Apr;52(4):760-4. doi: 10.1373/clinchem.2005.064337. Epub 2006 Feb 23.
Oxidized LDL (ox-LDL) plays an important role in the pathogenesis of coronary heart disease (CHD). Several tests for circulating ox-LDL have been published. We believe it is critical to carefully evaluate these assays because small differences in performance may have profound effects when results are compared; we therefore compared the analytical and clinical performances of 2 assays: one developed in our laboratory and a commercial assay (Mercodia) that uses the same monoclonal antibody (4E6).
We determined the variance of ox-LDL in both tests, including its longitudinal stability (n = 225; 3 time points per person) and its diagnostic accuracy, by ROC analysis of 95 consecutive CHD patients and 20 controls.
The between-person variability was 77% for the in-house assay (with the remaining 23% being within-person and analytical variance) and 74% for the commercial assay. For comparison, previously reported values were 66% for high-sensitivity C-reactive protein and 82% for total cholesterol. The areas under the curves for CHD in the 2 assays were identical (0.85). The odds ratios (logistic regression) for CHD among persons with high ox-LDL (>or=15 mg/L) compared with persons with low ox-LDL were not different: 4.3 (95% confidence interval, 1.4-12) for the in-house assay and 3.3 (1.1-10) for the commercial assay.
The longitudinal stability of ox-LDL, as assessed by multiple measures in people over time, is similar to that of total cholesterol and high-sensitivity C-reactive protein. Both assays tested similarly distinguish between healthy controls and CHD patients.
氧化型低密度脂蛋白（ox-LDL）在冠心病（CHD）发病机制中起重要作用。已有多项检测循环ox-LDL的方法发表。我们认为仔细评估这些检测方法至关重要，因为在比较结果时，性能上的微小差异可能会产生深远影响；因此，我们比较了两种检测方法的分析性能和临床性能：一种是我们实验室开发的方法，另一种是使用相同单克隆抗体（4E6）的商业检测方法（Mercodia）。
我们通过对95例连续的冠心病患者和20例对照进行ROC分析，确定了两种检测方法中ox-LDL的方差，包括其纵向稳定性（n = 225；每人3个时间点）及其诊断准确性。
内部检测方法的个体间变异性为77%（其余23%为个体内和分析方差），商业检测方法为74%。相比之下，先前报道的高敏C反应蛋白的值为66%，总胆固醇为82%。两种检测方法中冠心病的曲线下面积相同（0.85）。ox-LDL水平高（≥15 mg/L）者与ox-LDL水平低者相比，冠心病的比值比（逻辑回归）无差异：内部检测方法为4.3（95%置信区间，1.4 - 12），商业检测方法为3.3（1.1 - 10）。
通过对人群进行多次测量评估的ox-LDL纵向稳定性与总胆固醇和高敏C反应蛋白相似。两种检测方法在区分健康对照和冠心病患者方面表现相似。
