Nazir D J, McQueen M J
Department of Laboratory Medicine, Hamilton General Division, Hamilton Civic Hospitals, Ontario, Canada.
Clin Biochem. 1997 Mar;30(2):163-70. doi: 10.1016/s0009-9120(96)00163-4.
It is generally believe that lipoprotein(a) (Lp(a)) levels remain relatively constant in the same individual, but there is a paucity of data to substantiate this belief. This study was undertaken to determine the extent of intra-individual variation in Lp(a) over a 12-month period.
Lp(a) was measured monthly in duplicate over a 12-month period in 11 females and 11 males who were healthy, free-living, normal subjects by the Incstar Immunoprecipitin method using a goat antibody which was monospecific for Lp(a).
Some subjects showed considerable month-to-month variations which were not correlated with changes in other lipid parameters or with weight. Others showed fairly constant Lp(a) levels, with a few values which were quite different from the rest. This was not attributable to methodological factors; low and high controls gave mean (mg/L), SD and CV values of 181, 8.6, 4.7 and 431, 14, 3.3, respectively. The difference between the minimum and maximum values in the same individuals ranged from a low of 14 mg/L in one subject to a high of 229 mg/L in another over the one-year period.
Lp(a) showed greater intra-individual variations in normal subjects than is commonly believed. It is therefore recommended that Lp(a) should be measured sequentially over a few weeks to arrive at a mean value for assessing risk of coronary heart disease.
人们普遍认为，同一个体的脂蛋白(a)（Lp(a)）水平相对稳定，但缺乏数据证实这一观点。本研究旨在确定12个月内Lp(a)的个体内变异程度。
采用Incstar免疫沉淀法，使用对Lp(a)具有单特异性的山羊抗体，对11名健康、自由生活的正常女性和11名男性进行为期12个月的每月两次Lp(a)测量。
一些受试者的Lp(a)水平呈现出显著的逐月变化，且与其他血脂参数的变化或体重无关。另一些受试者的Lp(a)水平相当稳定，只有少数值与其他值差异较大。这并非方法学因素所致；低浓度和高浓度对照的平均（mg/L）、标准差和变异系数分别为181、8.6、4.7和431、14、3.3。在一年时间里，同一个体内Lp(a)最小值与最大值之间的差异，低至一名受试者的14 mg/L，高至另一名受试者的229 mg/L。
正常受试者中Lp(a)的个体内变异比通常认为的更大。因此，建议在几周内连续测量Lp(a)，以得出用于评估冠心病风险的平均值。
