Correlation Between Glycosylated HemoglobinA1c、Lipoprotein(a) And The Coronary Lesions In Patients With Coronary Heart Disease

Background and Objective.With the rapid development of economic and social life,unhealthy lifestyle andliving standards of people prevails. So coronary atherosclerotic heart disease(coronary atherosclerotic heart disease, CHD) incidence is increasing year by yearand it has become one of the most important diseases threatening people’s life andhealth, In Europe and the United States, the number of deaths from coronary heartdisease almost accounts for1/3-1/2of the total death and about50%-75%of the totalcardiac death each year.At present the number of coronary heart disease deaths inChina has ranked second in the world, becoming a serious threat to people’s healthand even life. As everyone knows, coronary heart disease is the most common diseasethat caused by atherosclerosis (Atherosclerosis, AS), and a large number of clinicalstudies show that AS advanced since childhood and developing gradually,thatgenerally shows a corresponding clinical symptoms to middle-aged and old period.The current research on coronary heart disease about etiology and pathogenesis is notcompletely understood, current studies suggest that it is caused by many factors, including age, gender, smoking, hypertension, hyperlipidemia, obesity, diabetes andabnormal glucose tolerance, lacking of physical exercise, family genetic factors, andthese are the risk factors for coronary heart disease. But in recent years, with thedeepening of the research and a large number of epidemiological investigation resultsshow that some new factors seem to be involved in the coronary artery disease, thesefactors include apolipoprotein A (Lp-a), fibrinogen（Fbg）, homocysteine (Hcy), blooduric acid（UA）, bilirubin(BIL), and C-reactive protein (CRP) etc..As early as10years ago, type2diabetes as a risk equivalent of CHD has beenidentified by domestic and foreign experts and scholars, in recent years, with theconstant improvement of awareness level, more and more evidence has proved thathyperglycemia is closely related to the formation and development of AS. Thepathogenic mechanism of AS may be related to impaired endothelial function,enhanced lipid oxidation, increased adhesion factor, blood coagulation dysfunction,oxidative stress and inflammatory factors. Glycosylated hemoglobin (HbA1c) as agood indicator of blood glucose control, it is the product of non enzymaticcondensation reaction and that is happening slowly in the blood by glucose andhemoglobin. Domestic and foreign clinical studies have shown that, as a riskfactor,HbA1c has a higher predictive value in the formation and development ofcoronary heart disease.Apolipoprotein A (LP-a) was found by Berg scientists NordicNorway in1963and mainly consists of LDL-C and Apo-A.Moreover the relatedbasic and clinical research show that is not only related with the disorder of lipidmetabolism, which plays a very important role in the progress of coronaryatherosclerosis formation, also is considered to be a risk factor for coronary heartdisease.Although the glycosylated hemoglobin (HbA1c) and apolipoprotein A (LP-a) asa risk factor for coronary heart disease has been accepted by most scholars at homeand abroad in this field, but there are still some problems to be solved:(1) therelationship between HbA1c and LP-a levels and the severity of coronary arterylesion in coronary heart disease?2. What are the possible mechanisms that induce toAS by HbA1c and Lp-a?(3) the relationship between HbA1c and LP-a in patientswith coronary artery disease? The purpose of this study is to explore the relationship between varietydegrees of HbA1c and LP-a levels and the degree of coronary artery disease, todiscuss the possible mechanism of CAS caused by HbA1c and LP-a, to furtheranalysis the relationship between different levels of HbA1c and LP-a, also to providenew ideas for slowing the progression of coronary artery disease and preventing therisk factors.Material and Method1Material398inpatients were selected for the study from the CardiovascularDepartment,the Second Affiliated Hospital of Zhengzhou University,who underwentCoronary angiography(CAG),there are261males and137females,age(60.41±16.8)years old. All subjects were excluded from the study of infectiousdiseases, malignant tumor, operation, trauma, coagulopathy,seriously failure functionof liver and renal, hyperthyroidism, and reduce the nephrotic syndrome.2Methods1Clinical and biochemical parameters were measured: All subjects enrolledwere detailed history,made physical examination,measured blood pressure,electrocardiogram,echocardiography,chest X-ray examination and other relatedinspection.In the second day early morning when the subjects were fasting andhorizontal position to draw venous blood to test liver and kidney function,fastingblood glucose(FBG),glycosylated hemoglobin(HbA1c),glucose tolerance2hoursblood glucose(2hPG),total cholesterol.l(TC),high density lipoprotein Cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C), triglyceride(TG),apolipoprotein A(LP-a) etc..2the diagnosis of coronary angiography and coronary heart disease:Applicationof Japan Toshiba Infinix VC multifunctional digital subtraction angiography machine,into the catheter through radial artery or femoral artery puncture, five or sixprojection position of the left coronary artery, right coronary angiography using twoor three position, angiography showed left main, left anterior descending branch ofleft circumflex degree, diameter≥50%stenosis, right can be defined. Crown fourvessels of any vessel coronary artery disease 3the extent of coronary artery disease in Gensini score:(1)according to thedifferent degree of stenosis coronary artery with different scores:when the coronaryangiography and coronary artery stenosis was1%~25%the score was1;when thecoronary artery stenosis was26%~50%the score was2;when the coronary arterystenosis was50%~75%the score was4; when the coronary artery stenosis was76%~90%the score was8;when the coronary artery stenosis was91%~99%thescore was16;when the coronary artery stenosis was100%the score was32;(2)whenthe coronary artery can be divided into14segments to determine the weightscoefficient of different coronary artery disease in different coronary arterysegments:the left main stem line number was5;the anterior descend in recentcoefficient was2.5,the middle coefficient was1.5, the apex coefficient was1, thecoefficient of the first diagonal branch was1,the second diagonal branch coefficientwas0.5;LCX proximal coefficient was2.5,the distal segment and the first obtusemarginal branch coefficient was1,posterior branch coefficient was0.5;the proximal tothe right coronary artery,in the middle,distal coefficient,after descending coefficientwere1.Segmental integral level segment weight coefficient multiplied by the narrowweight coefficient, total score for the integration of the sections and paragraphs.4.According to the results of coronary angiography were divided into coronaryheart disease group (n=316), non CHD group (control group, n=82); the2subcomponents:1.according to the level of HbA1c in CHD group from low to high intofive sub groups, group A (HbA1c <6%, n=164), group B [6.0%~6.4%], n=71, groupC[6.5%~6.9%],n=29, group D [6.0%~6.4%] n=40, E group (HbA1c>9%, n=12;2.according to the Lp-a level in CHD group from low to high into five sub groups,group I (Lp-a <10mg/dL), n=87, group Ⅱ Lp-a[10mg/dL~20mg/dL),n=96, groupⅢL p-a[20mg/dL~30mg/dL),n=72，group IVLp-a[30mg/dL~40mg/dL）n=45，groupV (Lp-a≥40mg/dL), n=16.5Statistical Methods: Data analysis using SPSS17.0software, P <0.05isconsidered statistically significant,P <0.01is considered statistically significant.Results1Comparison of coronary heart disease group and the control group, coronaryheart disease on age, sex, FBP,2hPG, LP-a, HbA1c was significantly higher (P <0.01); higher systolic blood pressure than the control group (P <0.05); HDL-Cwas significantly lower than the control group (P <0.01); number of cigarettessmoked, diastolic blood pressure, BMI, TG higher than the control group, TC,LDL-C lower than the control group, the difference was not statistically significant(P>0.05).2coronary heart disease A, B, C, D, E subgroup coronary score were [28（12) vs36（19) vs45（17） vs64（24) vs68（21)]，A group, B group, C group coronarygensini difference was statistically significant (P <0.05), D group, E group relativeto the A group, B group, C group coronary gensini score difference was statisticallysignificant (P <0.01), but the D, E groups coronary gensini score difference was notstatistically significant (P>0.05).stepwise correction for confounding factorsinfluence on coronary artery after coronary Gensini score, Gensini score wascorrelated with HbA1c level By using Spearman rank correlation analysis（r=0.070,P=0.023).3coronary heart disease I, Ⅱ, Ⅲ, Ⅳ, Ⅴ subgroup coronary score were [32(17)vs35(21) vs39(24) vs54(29) vs65(27)]，I group, Ⅱ group, Ⅲgroup coronarygensini score difference was not statistically significant (P>0.05), Ⅳ group,Ⅴgroup relative to the group I, Ⅱ group, Ⅲgroup coronary gensini score differencewas statistically significant (P <0.05), Ⅴgroup relative there was statisticallysignificant in group Ⅳ coronary gensini score differences (P <0.05).stepwisecorrection for confounding factors influence on coronary artery after coronaryGensini score, Gensini score was correlated with Lp-a level By using Spearman rankcorrelation analysis（r=0.064, P=0.047).4CHD A, B, C, D, E subgroup Lp-a levels were[25.04(9.38) vs26.12(10.64) vs26.72(13.23) vs27.14(14.19) vs29.25(15.78)]，there was no statistical differenceamong the five groups significance (P>0.05)；Spearman correlation analysis showedno correlation between HbA1c and Lp-a level (r=0.035, P=0.25).Conclusion1.HbA1c is associated with the severity of coronary artery disease, when HbA1c<7%, coronary lesions gradually increased with the increase of HbA1c level；whenHbA1c≥7%, coronary lesions with elevated levels of HbA1c increase significantly,but HbA1c≥7%compared with HbA1c <7%,coronary artery diseaseincrease significantly.2.LP-a <30mg/dL, Lp-a is not associated with the degree of coronary arterylesion, when Lp-a≥30mg/dL, coronary artery disease is aggravated with the increaseof Lp-a level.3.coronary heart disease patients with elevated HbA1c have no effect on Lp-a.