众所周知，血脂代谢紊乱是急性心肌梗死（AMI）的危险因子，特别是低密度脂蛋白胆固醇（LDL-C）和高密度脂蛋白胆固醇（HDL-C）。随着LDL-C水平的增高，患者将来发生AMI的风险也随之增高。与LDL-C不同的是，HDL-C则是AMI的保护因子，表现为HDL-C水平越高，患者越不容易发生AMI。然而，在AMI发生与发展的过程中，LDL-C和HDL-C除了作为危险（保护）因子外，是否还可以作为预后因子呢？
近期Am J Cardiol在线刊登的一篇论文指出，LDL-C与AMI患者院内死亡密切相关。研究者对美国国家心肌梗死登记中心（National Registry of Myocardial Infarction，NRMI）的数据库进行了分析，采用多元logistic回归评价了115492名AMI患者就诊24小时内的血脂水平与院内死亡的关系。研究人员发现：LDL-C水平越高，患者发生院内死亡的风险越小。多变量的logistic回归结果表明：与LDL-C小于77 mg/dl的患者相比，LDL-C大于128 mg/dl的患者发生院内死亡的优势比（OR）为0.85（95%CI: 0.76-0.96）。最重要的是，LDL-C与AMI患者院内死亡的关联性与患者发病前是否接受降脂药物治疗无关，即不论患者入院前是否接受过降脂药物治疗，LDL-C增高均与院内死亡风险降低有关。相比之下，HDL-C与患者院内死亡的关系并不十分明显。
研究者指出，在AMI发生与发展的过程中，患者可能发生继发性肝脏功能衰竭，LDL-C的合成能力随之降低。因此，LDL-C的水平在一定程度上反映了肝脏的受损程度，其水平越低，表明肝脏受损程度越严重，患者的预后也因此越差。该研究发现LDL-C与AMI患者的近期预后密切相关，提示在AMI的救治过程中，可以将LDL-C视为一个近期预后判断指标。 |
原文信息
Relation between Serum Low-Density-Lipoprotein Cholesterol and In-Hospital Mortality Following Acute Myocardial Infarction (The Lipid Paradox)
The American Journal of Cardiology,2015: in press
Lipoprotein levels are currently recognized as independent risk factors for long-term cardiovascular events after acute myocardial infarction (AMI). During the acute-phase reaction following AMI, previous studies have reported trends of decreased low-density lipoprotein cholesterol (LDL-C), increased triglycerides, and variable high-density lipoprotein cholesterol (HDL-C) levels, often proportional to the severity of myocardial necrosis. However, the association between LDL-C and HDL-C levels and in-hospital mortality has not been well established following AMI. The relationship between lipid levels and in-hospital all-cause mortality in 115,492 patients hospitalized for AMI (July 2002–December 2006), registered in the National Registry of Myocardial Infarction (NRMI) 4b–5, was evaluated using multivariable-adjusted logistic regression models. Mean LDL-C was 104 ± 38, HDL-C 41 ± 14 and triglycerides 143 ± 83 (mg/dl). Compared with the lowest quartile of LDL-C (< 77 mg/dl), the risk of in-hospital mortality in the 2nd– 4th quartiles was decreased (adjusted odds ratio [OR] = 0.79, 0.80 and 0.85, respectively). For HDL-C, only those in the lowest quartile (< 31 mg/dl) had higher risk of in-hospital mortality (OR = 1.20) compared with the highest quartile (≥ 47 mg/dl). Results from NRMI 4b−5 suggest a lipid paradox, with lower LDL-C levels associated with increased risk of in-hospital mortality, contrary to findings outside of the acute setting. Consistent with previous analyses, lowest HDL-C levels were associated with increased in-hospital mortality. In conclusion, further explorations of the relationship between very low levels of LDL-C, myocardial necrosis and subsequent adverse cardiovascular events are warranted.
原文链接：http://www.sciencedirect.com/science/article/pii/S0002914914022693 |
