The Clinical Significance Of The Detection Of Lipoprotein Particles In The High-risk Population Of Coronary Heart Disease

Objective Cigarette smoking is one of the established risk factors of atherosclerotic cardiovascular disease.The incidence of coronary heart disease in smokers is twice as many as non-smokers,but the mechanism is not yet completely clear.It has been confirmed that the blood lipid profile of smokers has an undesirable change,that is,the levels of total cholesterol,low-density lipoprotein cholesterol and triglyceride are relatively high,and the level of high-density lipoprotein cholesterol is relatively low.In recent years,with the deepening of blood lipid research,some scholars have found that lipoprotein particles are more reflective of the occurrence and development of atherosclerotic diseases than lipoproteins.Previous studies have suggested that smoking status(such as persistent smoking or quitting smoking)may have an impact on the body's lipid profile and lipoprotein function.However,its possible effect on lipoprotein particles has been less reported.The aim of this study was to examine the differences in lipoprotein subfractions between different smoking states(non-smoking,smoking cessation,and persistent smoking)in patients with chest pain that had no history of the use of lipid-lowering drugs,and to explore the possible distribution of lipoprotein particles in smoking status.The impact provides new evidence for the high incidence of atherosclerotic disease caused by smoking.Methods The study included 877 consecutive patients with chest pain who had not been treated with lipid-lowering drugs.According to smoking history,patients were divided into three groups,nonsmoking(n = 518),smoking cessation group(smoking cessation for at least 6 months,n = 103)and current smoking(more than 100 consecutive smoking,n = 256)group.The baseline clinical data and laboratory test results of the enrolled patients were collected and improved,and the remaining blood samples were further tested.Detection of lipoprotein subfractions using the Quantimetrix Lipoprint System,the low-density lipoprotein(LDL)and the high-density lipoprotein(HDL)were divided into 3 subfractions as large,medium and small lipoprotein subfractions respectively.Then the effects of different smoking states on lipoprotein particles were compared.Results After adjusting for risk factors such as sex,age,body mass index,drinking history,family history of coronary heart disease,systolic blood pressure,HbAlc,and coronary heart disease,compared with nonsmoking subjects,the current smoking group had significantly lower large/medium HDL-C(both P<0.001)concentration and large HDL subfraction percentage but higher small HDL-C and medium LDL-C concentrations as well as medium LDL subfraction percentage.Importantly,former smoking subjects showed elevated levels of large HDL-C concentration,large HDL particle percentage,and mean LDL particle size and attenuation in small HDL/LDL percentages and small LDL-C concentration,but these levels did not reach the optimal status compared with those of the non-smoking group.Conclusion Our cross-sectional observations in Chinese populations that have not received lipid-lowering drugs suggest that smoking will significantly reduce atherosclerotic lipoprotein particles such as large HDL subfractions and at the same time increase atherogenic lipoprotein particles such as small LDL subfractions;but if individuals quit smoking for more than 6 months,he/she can reverse a number of adverse effects to some extent.Background:A large number of studies have confirmed that diabetic patients are at high risk of coronary heart disease(CAD).Dyslipidemia is a potential risk factor for the high incidence of coronary heart disease.Diabetic patients with dyslipidemia usually present with elevation of fasting and postprandial triglyceride(TG),low-density lipoprotein(LDL),and low-density lipoprotein cholesterol(LDL-C),whereas reduction of high-density lipoprotein(HDL)and high-density lipoprotein cholesterol(HDL-C).Besides,their small dense LDL particles(sdLDL)change significantly.However,studies on the distribution characteristics and possible clinical significance of lipoprotein subfractions in patients with type 2 diabetes(T2D)are still insufficient.The purpose of this study was to analyze the distribution of lipoprotein subfractions in patients with T2D and to explore the clinical significance of the changes.Methods:920 consecutive patients with no history of lipid-lowering drugs were included in the study.Patients were divided into T2D group(n = 204)and non-T2D group(n =716)based on whether or not T2D was combined.Quantitative analysis of LDL and HDL subfractions was performed using the Quantimetrix Lipoprint system.Then,the distribution of lipoprotein subfractions in T2D patients and non-T2D patients was compared and analyzed.Results:Consistent with previous reports,T2D patients showed a higher incidence of dyslipidemia,which was characterized by a significant increase in TG levels(2.07 ±1.14 mmol/1 vs 1.77 ±0.99 mmol/1,P = 0.005).There were upward trends in LDL-C and TC levels,but the difference was not statistically significant(4.93 ± 1.06 mmol/I vs 4.80±0.93mmol/l,P = 0.110;3.28 ± 0.93 mmol/1 vs 3.16 ± 0.88 mol/l,P = 0.084).Compared with the non-T2D group,the concentration of large HDL-C subfractions,the percentage of large HDL subfractions and the average LDL particle size were decreased,and the concentration of small HDL-C/LDL-C subfractions and the percentage of HDL and small LDL subfractions were increased.In addition,Logistics regression analysis revealed that the concentrations of small HDL-C and small LDL-C subfractions,the percentages of small HDL and large HDL subfractions,and the mean LDL particle size were independently associated with T2D(small HDL-C subfractions concentrations:95%CI = 1.009-1.067,P = 0.009;small LDL-C subfractions concentrations:95%CI =0.938-0.983,P=0,001;small HDL subfractions percentage:95%CI=1.023-1.135,P=0.005;large HDL subfractions percentage:95%CI=1.005-1.048,P=0.014;mean LDL particle size:95%CI =0.940-0.999,P=0.040;respectively).Conclusions:The present study suggested that,in addition to the changes in traditional lipid profile such as TG,TC,and LDL-C,dyslipidemia in T2D patients has a significant abnormal distribution of lipoprotein subfractions,manifested as a decrease in the concentration of large HDL-C subfractions,the percentage of large HDL subfractions,and the mean LDL particle size,whereas a increade in the concentration of small HDL-C and small LDL-C,and the percentage of small HDL and small LDL subfractions.The above results provide new ideas for prevention and treatment of CAD in patients with T2D.Background:t has been confirmed that low-density lipoprotein cholesterol(LDL-C)is the most important risk factor for coronary artery disease(CAD).Oxidation of LDL is considered as a key link in the occurrence and development of CAD.The monitoring indicator of LDL oxidation is called oxidized low-density lipoprotein(ox-LDL).At the same time,high-density lipoprotein(HDL)is considered as an important component in anti-atherogenic lipids,and its size is highly heterogeneous,the so-called subfractions,and in recent years,the detection of subfractions is considered to better predict CAD than quantitative analysis of HDL cholesterol(HDL-C).Given that both ox-LDL and HDL subfractions are important in the development and progression of CAD,the ox-LDL and HDL subfractions in patients undergoing non-lipidrnic therapy with coronary angiography(CAG)were tested to see if there was a link between the two markers.Methods:A total of 1417 individuals were consecutively enrolled and divided into CAD(n=942)and non-CAD groups(n=475).The severity of CAD was assessed by Gensini Scores(GS)system.Then,the relationships between ox-LDL and HDL subfractions were evaluated.Results:Compared with non-CAD subjects,CAD patients had higher ox-LDL but lower concentrations of HDL cholesterol(HDL-C,p=0.002)as well as large HDL subfractions(p=0.004).Moreover,ox-LDL were negatively correlated with large HDL subfractions but not HDL-C and this correlation only existed in severe CAD(all p<0.05).Interestingly,ox-LDL was elevated and large HDL subfractions decreased with the increase of the number of stenotic coronary arteries and GS(all p<0.05).Conclusion:Ox-LDL levels are higher in severe CAD patients and negatively associated with large HDL subfraction,suggesting that the interaction of ox-LDL and HDL subfractions in the status of atherosclerosis may need further investigation.