Griffin B A, Freeman D J, Tait G W, Thomson J, Caslake M J, Packard C J, Shepherd J
Institute of Biochemistry, Royal Infirmary, Glasgow, UK.
Atherosclerosis. 1994 Apr;106(2):241-53. doi: 10.1016/0021-9150(94)90129-5.
The concentration of plasma LDL subfractions is described in four groups of normocholesterolaemic (total plasma cholesterol < 6.5 mmol/l) male subjects consisting of men with and without coronary artery disease (CAD+/-), as determined by angiography, post-myocardial infarct survivors (PMI) and normal, healthy controls. The CAD(+) and PMI groups were distinguished from the CAD(-) and controls by raised concentrations of plasma triglyceride, very low density lipoprotein (VLDL) cholesterol, small, dense LDL (LDL-III density (d) 1.044-1.060 g/ml) and lower concentrations of high density lipoprotein (HDL) cholesterol and large, buoyant LDL (LDL-I d 1.025-1.034 g/ml). In all groups, a subfraction of intermediate density, LDL-II (d 1.034-1.044 g/ml), was the predominant LDL species but was not related to coronary heart disease risk. Plasma triglyceride showed a positive association with LDL-II (r = 0.51, P < 0.001) below a triglyceride level of 1.5 mmol/l. Above this threshold of 1.5 mmol/l, LDL-II and LDL-I showed significant negative associations with triglyceride (LDL-II r = -0.5, P < 0.001; LDL-I r = -0.45, P < 0.001). Small, dense LDL-III showed a weak positive association with triglyceride that became highly significant above the 1.5 mmol/l threshold (r = 0.54, P < 0.001). While age was positively related to LDL-II within the control subjects (r = 0.3, P < 0.05), there was no difference in the percentage abundance or concentration of LDL-III within control and CAD(-) subjects above and below the age of 40 years. Smoking was associated with a relative deficiency of the LDL-I subfraction (LDL-I to LDL-III ratio in smokers = 0.77, in ex-smokers = 0.95, in non-smokers = 1.89; P < 0.01), as was beta-blocker medication (% LDL-I, users vs. non-users, P < 0.05). Both of these effects could be explained by their primary influence on plasma triglyceride. Analysis of the frequency distributions for the three LDL subfractions revealed the concentration of small, dense LDL-III to be bimodal around a concentration of 100 mg (lipoprotein mass)/100 ml plasma. The calculation of odds ratios based on this figure indicated relative risk estimates of 4.5 (chi 2: P < 0.01) for the presence of coronary artery disease and 6.9 (chi 2: P < 0.001) for myocardial infarction.(ABSTRACT TRUNCATED AT 400 WORDS)
血浆低密度脂蛋白（LDL）亚组分的浓度在四组血浆胆固醇正常（总血浆胆固醇<6.5 mmol/l）的男性受试者中进行了描述，这些受试者包括经血管造影确定患有和未患有冠状动脉疾病（CAD+/-）的男性、心肌梗死后幸存者（PMI）以及正常健康对照者。CAD（+）组和PMI组与CAD（-）组及对照组的区别在于，前两组血浆甘油三酯、极低密度脂蛋白（VLDL）胆固醇、小而密LDL（LDL-III密度（d）1.044 - 1.060 g/ml）浓度升高，高密度脂蛋白（HDL）胆固醇和大而轻的LDL（LDL-I d 1.025 - 1.034 g/ml）浓度降低。在所有组中，中等密度的LDL-II亚组分（d 1.034 - 1.044 g/ml）是主要的LDL种类，但与冠心病风险无关。在甘油三酯水平低于1.5 mmol/l时，血浆甘油三酯与LDL-II呈正相关（r = 0.51，P < 0.001）。高于1.5 mmol/l这个阈值时，LDL-II和LDL-I与甘油三酯呈显著负相关（LDL-II r = -0.5，P < 0.001；LDL-I r = -0.45，P < 0.001）。小而密的LDL-III与甘油三酯呈弱正相关，在1.5 mmol/l阈值以上变得高度显著（r = 0.54，P < 0.001）。在对照受试者中，年龄与LDL-II呈正相关（r = 0.3，P < 0.05），40岁以上和以下的对照受试者与CAD（-）受试者中，LDL-III的相对丰度或浓度没有差异。吸烟与LDL-I亚组分相对缺乏有关（吸烟者LDL-I与LDL-III的比值 = 0.77，既往吸烟者 = 0.95，非吸烟者 = 1.89；P < 0.01），β受体阻滞剂药物治疗也有此关联（%LDL-I，使用者与非使用者相比，P < 0.05）。这两种效应都可以通过它们对血浆甘油三酯的主要影响来解释。对三种LDL亚组分频率分布的分析显示，小而密的LDL-III浓度在100 mg（脂蛋白质量）/100 ml血浆左右呈双峰分布。基于这个数值计算比值比表明，存在冠状动脉疾病的相对风险估计值为4.5（卡方检验：P < 0.01），心肌梗死的相对风险估计值为6.9（卡方检验：P < 0.001）。（摘要截断于400字）
