Study On The Relationship Between OX-LDL&the Ratio And Acute Cerebral Infarction

Objective: Intracranial and extracranial atherosclerotic thrombosis is the leading cause of acute cerebral infarction.Oxidative stress is the main characteristic of atherothrombotic cerebral infarction.Oxidized low density lipoprotein(OX-LDL)is the important biomarker reflecting the oxidative stress level and plays a crucial role in atherosclerosis initiation and progression.Elevated plasma OX-LDL levels are closely associated with atherosclerotic disease.Through determinating plasma OX-LDL levels by the enzyme-linked immunoassay and calculating the value of OX-LDL/TC,OX-LDL/HDL and OX-LDL/LDL,this study explored the value in diagnosis and classification of acute cerebral infarction,as well as the relationship between OX-LDL & its ratio and the severity & short-term prognosis of acute cerebral infarction.Methods:The case group was consisted of 94 patients(74 male,20 female)with acute cerebral infarction in the Second Hospital of Hebei Medical University from December 2015 to December 2016,aged from 40 to 85 years old(mean age 61.29±8.33).All patients hospitalized within 72 hours after onset of symptoms met the diagnostic criteria of acute cerebral infarction made in the fourth national conference on cerebrovascular disease.In accordance with the TOAST criteria,all patients with acute cerebral infarction were further classified into different stroke subtypes:1)large-artery atherosclerosis(LAA),including 61cases;2)small-artery occlusion(SAO),including 33 cases.The controls were 35 healthy volunteers(26 male and 9female,aged from 40 to 85 years,mean age 59.17±10.07)selected from the health examination center in the Second Hospital of Hebei Medical University.General information of all patients were collected,including age,gender,blood pressure,previous history,total cholesterol,triglyceride,high-densitylipoprotein cholesterol(HDL-c),low-density lipoprotein cholesterol(LDL-c),hs-CRP,Hcy and so on.NIHSS score was assigned at admission,and again 14 days after admission or at discharge.The plasma OX-LDL levels were measured using the enzyme-linked immunoassay and the value of OX-LDL/TC,OX-LDL/HDL and OX-LDL/LDL were calculated.Results:1 There was no statistical difference in gender,age,smoking,diabetes and coronary heart disease,diastolic blood pressure,triglycerides,high-density lipoprotein cholesterol and uric acid between case group and control group(P>0.05).But the difference in systolic blood pressure,hs-CRP,homocysteine,total cholesterol and low-density lipoprotein cholesterol between two groups was statistically significant(P<0.05).2 The difference of the plasma OX-LDL levels and the value of OX-LDL/TC,OX-LDL/HDL,OX-LDL/LDL between case group and control group[57.59±24.48VS32.00±14.18,12.70(7.95,17.34)VS7.46(5.38,10.44),52.26(33.13,69.32)VS24.88(19.87,40.37),18.91(12.18,24.44)VS12.93(8.68,16.98)]were statistically significant(P<0.001).Receiver-operating characteristic curve analyses were used to evaluate the diagnostic accuracies of OX-LDL and the ratio.the TC levels with the area under the curve of 0.599 were no statistical difference.The levels of LDL,and hs-CRP with the area under the curve less than 0.7 had lower diagnostic value.The OX-LDL and the ratio and Hcy with the area under the curve more than 0.7(P<0.001)had good diagnostic accuracy.The OX-LDL with area under the curve of 0.807(P<0.001)had the highest diagnostic accuracy in distinguishing healthy controls from patients with acute cerebral infarction.At a cut-off value of 45.35 U/ml,sensitivity was64.9% and specificity was 88.6%.3 The plasma OX-LDL levels in LAA group,SAO group and control group was respectively 62.79±24.96,47.98±20.67,32.00±14.18.OX-LDL/TC was respectively 13.13(9.41,19.26),9.91(6.92,15.19),7.46(5.38,10.44).OX-LDL/HDL was respectively 55.79(40.11,79.66),39.24(22.31,59.81),24.88(19.87,40.37).OX-LDL/LDL was respectively 21.07(14.67,30.71),16.73(10.86,23.73),12.93(8.68,16.98).The value of OX-LDL,OX-LDL/TC and OX-LDL/HDL were significantly higher in LAA group and SAO group than in control groups and the difference was statistically significant(P<0.05).The value of OX-LDL/LDL were significantly higher in LAA group than in control group and the difference was statistically significant(P < 0.05).But there was no statistically difference between SAO group and control group in OX-LDL/LDL(P>0.05).The value of OX-LDL,OX-LDL/TC,OX-LDL/HDL and OX-LDL/LDL were higher in LAA group than in SAO group and was statistically significant(P<0.05).4 Through Spearman rank correlation analysis,only OX-LDL/TC in LAA group was mildly positively correlated to the NIHSS score at admission(r=0.265,P=0.265),however,there was no association between OX-LDL,OX-LDL/TC,OX-LDL/HDL and NIHSS score at admission(P>0.05).OX-LDL and the ratio in SAO group had no significant correlation with NIHSS score at admission(P>0.05).And furthermore,OX-LDL and the ratio between two groups at discharge had no significant correlation(P>0.05).5 In the case group OX-LDL showed positive correlation with hs-CRP(r=0.661,P=0.000),but no correlation with age,blood pressure,TC,TG,HDL,LDL and so on.OX-LDL/TC were positively correlated with hs-CRP(r=0.533,P=0.000),and negatively correlated with TC,TG,HDL and LDL(r=-0.379,P=0.000;r=-0.206,P=0.046;r=-0.244,P=0.018;r=-0.361,P=0.000).OX-LDL/HDL were positively correlated with hs-CRP(r=0.568,P=0.000),and negatively correlated with HDL(r=-0.443,P=0.000).OX-LDL/LDL were positively correlated with hs-CRP(r=0.476,P=0.000),and negatively correlated with TC,HDL and LDL(r=-0.462,P=0.000;r=-0.234,P=0.023;r=-0.477,P=0.000),but no correlated with other factors,such as gender,age,Hcy and so on.Conclusion:1 The OX-LDL,OX-LDL/TC,OX-LDL/HDL and OX-LDL/LDL in patients with acute cerebral infarction were significantly elevated.OX-LDL and the ratio had good value in early diagnosis of acute cerebral infarction.2 The OX-LDL,OX-LDL/TC,OX-LDL/HDL and OX-LDL/LDL were closely associated with large artery atherosclerosis and small artery occlusion stroke according to TOAST criteria.3 Only in LAA group,the value of OX-LDL/TC could reflect the initial severity of acute cerebral infarction,but it could not predict the short-term prognosis of acute cerebral infarction.4 The OX-LDL and the ratio had significantly positive correlation with hs-CRP,and they might play an important role in the initiation and progression of acute cerebral infarction together.