Stampfer M J, Sacks F M, Salvini S, Willett W C, Hennekens C H
Channing Laboratory, Department of Medicine, Boston, MA 02115.
N Engl J Med. 1991 Aug 8;325(6):373-81. doi: 10.1056/NEJM199108083250601.
The independent contributions of subfractions of high-density lipoprotein (HDL) cholesterol (HDL2 and HDL3) and apolipoproteins in predicting the risk of myocardial infarction are unclear. Prospective data are sparse, but HDL2 is widely believed to be a more important predictor than HDL3.
Blood samples were collected at base line from 14,916 men (ages, 40 to 84 years) who were participants in the Physicians' Health Study. After five years of follow-up, plasma samples from 246 men with new myocardial infarction (case subjects) were analyzed together with specimens from 246 men matched to them for age and smoking status who had not had a myocardial infarction.
The levels of total cholesterol and apolipoprotein B-100 were significantly associated with an increased risk of myocardial infarction (data on levels of low-density lipoprotein cholesterol were unavailable). Both HDL cholesterol and HDL2 levels were associated with a substantially decreased risk of myocardial infarction, but the HDL3 level was the strongest predictor; the relative risk was 0.3 (95 percent confidence interval, 0.2 to 0.6) for those in the fifth of the group with the highest HDL3 levels, as compared with the fifth with the lowest levels. The benefit of a higher HDL cholesterol level was most pronounced among those with lower total cholesterol levels. Levels of apolipoprotein A-I and apolipoprotein A-II were also associated with decreased risk. However, the levels of HDL subfractions and apolipoproteins did not add significantly to the value of a multivariate model that included the ratio of total to HDL cholesterol in predicting myocardial infarction, whereas that ratio remained a significant independent predictor of risk. After adjustment for other risk factors, a change of one unit in the ratio of total to HDL cholesterol was associated with a 53 percent change in risk (95 percent confidence interval, 26 percent to 85 percent).
This study underscores the importance of HDL cholesterol in predicting the risk of myocardial infarction and demonstrates protective effects of both the HDL3 and HDL2 subfractions of HDL cholesterol. We found little or no predictive value for the levels of apolipoproteins A-I, A-II, and B or HDL subfractions after conventional risk factors and the ratio of total to HDL cholesterol were considered.
高密度脂蛋白（HDL）胆固醇的亚组分（HDL2和HDL3）及载脂蛋白在预测心肌梗死风险中的独立作用尚不清楚。前瞻性数据稀少，但普遍认为HDL2比HDL3是更重要的预测指标。
从参加医师健康研究的14916名男性（年龄40至84岁）基线时采集血样。经过五年随访，对246名新发心肌梗死男性（病例组）的血浆样本与246名年龄和吸烟状况与之匹配且未发生心肌梗死的男性（对照组）样本进行分析。
总胆固醇和载脂蛋白B-100水平与心肌梗死风险增加显著相关（低密度脂蛋白胆固醇水平数据不可用）。HDL胆固醇和HDL2水平均与心肌梗死风险大幅降低相关，但HDL3水平是最强的预测指标；HDL3水平处于最高五分位组的人群与最低五分位组相比，相对风险为0.3（95%置信区间，0.2至0.6）。HDL胆固醇水平较高的益处在总胆固醇水平较低的人群中最为明显。载脂蛋白A-I和载脂蛋白A-II水平也与风险降低相关。然而，在预测心肌梗死的多变量模型中，HDL亚组分和载脂蛋白水平并未显著增加已包含总胆固醇与HDL胆固醇比值模型的预测价值，而该比值仍是风险的显著独立预测指标。在调整其他风险因素后，总胆固醇与HDL胆固醇比值每变化一个单位，风险变化53%（95%置信区间，26%至85%）。
本研究强调了HDL胆固醇在预测心肌梗死风险中的重要性，并证明了HDL胆固醇的HDL3和HDL2亚组分均具有保护作用。在考虑传统风险因素和总胆固醇与HDL胆固醇比值后，我们发现载脂蛋白A-I、A-II和B水平或HDL亚组分几乎没有预测价值。
