The Effect Of HDL Cholesterol Reverse Transport Function On The Prognosis Of Coronary Heart Disease

BackgroundMany evidence-based medical evidences have indicated that dyslipidemia isregarded as the most important risk factor of coronary heart disease (CHD)currently,and also closely related to its prevelence, development and prognosis.Clinicalmedicine has manifested that the low level of high-density lipoprotein cholesterol(HDL-C) is acted as an independent risk factor to coronary heart disease(CHD).However,regular blood lipid measurements that clinical laboratory tested such asHDL-C only represent the cholesterol content of lipoprotein,which is not parallel to thelipoprotein particle content and lipids ratio. Increasing studies has found that HDLcholesterol efflux capacity (HCEC) can be used as an index of high-density lipoprotein(HDL) function,which is not relevant with HDL-C levels,also shows negativecorrelation with the occurrence of CHD. Nevertheless,this view has not been widelyconfirmed. Current research suggests that the total cholesterol content of erythrocytemembranes(CEM) are several times higher than other cell membranes,also play animportant role in the progression of CHD.Our team has found that CEM in CHDpatients was significantly higher than control group. However, the mechanism ofreverse cholesterol transport in erythrocyte membranes and the HCEC influence theprognosis of patients with CHD is still not unclear.ObjectiveTo observe the difference of serum HCEC among stable angina pectoris(SAP), unstableangina pectoris(UAP) and acute myocardial infarction(AMI).analyse the correlationbetween HCEC and CEM levels, and the prognosis of patients with CHD,to further discuss why the levels of CEM in CHD subjects is higher than control group. and howHCEC affect the prognosis of patients with CHD.Methods(1)Research groups159subjects with chest pain and(or) chest tightness wererecruited, then assigned into three groups according to their clinical symptoms and theresults of coronary artery angiography and successful followed-up after discharge fromhospital: SAP group(n=36); UAP group(n=65);AMI group(n=58).(2) The amount ofCEM The arterial blood samples were collected during the coronary angiographyprocess, extract erythrocyte membranes from the blood, and then evaluate the levels ofCEM by the enzymatic assay.(3) The level of serum HCEC The arterial blood sampleswere collected during the coronary angiography process, extract serum from arterialblood,after culturing J774cells then evaluate the levels of HCEC by liquid scintillationcounting..(4)Statistical methods All the results for continuous variables are presentedas means and standard deviation(SD). As medians if the distributions were skewed andas percentages for categorical data.Cox proportional hazards model was used to conductmultiple factors regression analysis,then concluded the RR values and95%CI of eachvariable. The Situation of two groups was carried out by Kaplan-Meier curve.TheSPSS13.0ststistical software package was used for all calculations, a P value﹤0.05was considered to indicate statistical significance.Results(1) Clinical datas have no statistical difference between SAP, UAP and AMI groups(P<0.05)；(2) Compared with SAP group (11.80±3.66), the serum HCEC values of AMIgroup(10.10±4.07) were significantly decreased（p=0.017）, the serum HCEC values ofUAP group(10.25±3.93) were higher than that of SAP group, but there was no statisticaldifference.(3) serum HCEC Predict discharge events in CHD patients Take10.34% (median) as the HCEC grouping cut-off point, we discovered the incidence of theprimary end point events while HCEC≤10.34%are Significantly higher than that ofHCEC>10.34%（p<0.05），except for nonfatal stroke。Also the incidence of thesecondary end points events while HCEC≤10.34%and that of HCEC>10.34%，butthere were no statistically significant differenc（ep>0.05）.Cox regression analysis resultsshowed that the HCEC only has value in predicting the primary end point events, withno obvious prediction in the secondary end points event （RR=0.445,95%CI:0.116-1.711, P=0.239）.What’s more, the incidence of the primary end point eventswhile HCEC≤10.34%are Significantly higher than that of HCEC>10.34%（RR=0.171,95%CI:0.036-0.824, P=0.028）.the Kaplan-Meier curve revealed the incidence of theprimary end point events while HCEC≤10.34%are Significantly higher than that ofHCEC>10.34%（p=0.018）, we also found that HCEC only have predictive value for theoccurrence of stroke after further analysis.Conclusion(1)Compared with SAP group, serum HCEC levels of AMI group are significantlydecreased;(2)Serum HCEC have some values on predicting primary end point eventsin patients with coronary heart disease.(3)Serum HCEC have some values onpredicting nonfatal stroke in patients with coronary heart disease.