Analysis Of Risk Factors For In-stent Restenosis Of Coronary Heart Disease And Determination Of The Optimal Threshold Of Triglyceride

BackgroundsChina cardiovascular disease report 2018 points out that the number of patients with coronary heart disease(CHD)in China is increasing year by year,and the portion of younger patients is raising.Percutaneous coronary intervention(PCI)has become a common and important treatment,reducing the mortality of CHD.However,the incidence of in-stent restenosis(ISR)has limited its clinical application.It was found that the most important risk factors of ISR were lipid abnormal and diabetes mellitus.Low-density lipoprotein cholesterol(LDL-C)level of CHD patients after PCI should be less than 1.8mmol/L.However,in recent years,it has reported that the occurrence rate of ISR is still high even though the level of LDL-C of CHD patients after PCI reaches the target level.Secondary dyslipidemia,such as hypertriglyceridemia,plays a critical role in ISR.Hypertriglyceridemia can increase the incidence rate of CHD.However,for CHD patients in very high-risk group,whether the level of triglyceride should be reduced to a lower level rather than 1.7mmol/L is still uncertain.ROC curve was used to analyze the optimal threshold of triglyceride in the very high-risk population of CHD.Furthermore,it has been reported that diabetic patients are often accompanied with dyslipidemia,and diabetes mellitus is also an independent risk factor for ISR.The incidence of ISR in patients with diabetes and CHD was 2～4 times as high as that in patients with CHD alone.Compared with CHD patients after PCI,whether LDL-C of patients with diabetes after PCI needs to be reduced to a lower level,and whether further strengthening lipid-lowering treatment can obtain more cardiovascular benefits,the associated research is less studied.In this paper,we further discussed the difference of lipid level and the incidence rate of ISR between diabetic and non-diabetic patients,and makes clear whether the patients with CHD and diabetes should strengthen the lipid-lowering treatment.ObjectiveTo explore the optimal threshold of triglyceride in CHD patients after PCI whose LDL-C level is less than 1.8mmol/L.To compare the difference of lipid level and the incidence rate of ISR between diabetic patients and non-diabetic patients,in order to determine whether CHD patients with diabetes is needed to strengthen lipid-lowering therapy.MethodsThis is a retrospective study.We included 368 patients with coronary heart disease after PCI from June 2012 to December 2018 in the First Affiliated Hospital of Zhengzhou University.The LDL-C level of these patients was less than 1.8mmol/l before PCI,and patients with serious heart failure,coronary artery bypass grafting,serious liver and kidney dysfunction,malignant tumor,infectious disease and autoimmune disease were excluded.Followed for a year,according to the results of angiography reexamination,patients were divided into two groups:ISR group(n=175,including 121 males and 54 females,aged 59.23± 9.53 years)and non-ISR(n=193,including 146 males and 47 females,aged 58.38 ± 9.80 years)group.The differences of ISR and related risk factors between the two groups were compared and using ROC curve determine the optimal threshold of triglyceride.In order to compare the difference of lipid level and the incidence rate of ISR between diabetes and non-diabetes patients,we divided the patients into two groups:diabetes group(n=109,including 76 males and 33 females,aged 58.48 ± 9.06 years)and non-diabetes group(n=259,including 193 males and 66 females,aged 58.91±9.93 years).Results1.Comparison of general data between two groups:Compared with the non-ISR group,ISR group had more patients with hypertension(107 vs.94,P=0.017)and diabetes(77 vs.32,P<0.001),and the levels of LDL-C(1.51±0.22 vs.1.41±0.25,P<0.001)and triglyceride(1.47±0.79 vs.1.04±0.51,P<0.001)were higher.Furthermore,there were more patients with severe vascular disease in ISR group(132 vs.117,P=0.002).Other risk factors had no difference between two groups.2.Analysis of risk factors promoting ISR:According to univariate and multivariate logistic regression analysis,"gender,diabetes mellitus,LDL-C,triglyceride,number of stents" were independent risk factors of ISR.3.Selection of critical value of blood lipid:Using ROC curve analysis,the suitable critical value of LDL-C was 1.4mmol/L,which was consistent with the latest lipid guideline of ESC/EAS in 2019.The optimal threshold of triglyceride is 1.0mmol/l.The area under the curve(AUC)is 0.713,the sensitivity and specificity are 72%and 66%,respectively.4.Comparison between diabetic and non-diabetic patients:Compared with non-diabetic patients,the prevalence of hypertension(71 vs.130,P=0.009)in diabetic patients was higher.At the same time,the levels of LDL-C(1.51 ±0.18 vs.1.43±0.26,P=0.003)and triglyceride(1.45±0.75 vs.1.16±0.64,P<0.001)and the incidence of ISR(77 vs.98,P<0.001)were higher in diabetic patients.Other risk factors had no difference between two groups.Conclusions1.For CHD patients in very high-risk group,the level of triglyceride should be lower than 1,0mmol/L,instead of 1.7mmol/L.2.For patients with diabetes and CHD,we should strengthen the lipid-lowering treatment.