Plasma Osteoprotegerin Correlates Well To The Occurrence Of Microembolic Signals In Acute Atherosclerotic Stroke Patients

Background Instability of atherosclerotic plaque is associated with the occurrence of stroke.Microembolic signal(MES)is an indicator of unstable plaque.We identified a relationship between plasma osteoprotegerin(OPG)and ischemic stroke.Thus,we investigate whether plasma OPG level relate to MES and further evaluate the feasibility of OPG as a biomarker of stroke severity and MES.Methods Our study consisted of 127 patients with large artery atherosclerosis(LAA)stroke in anterior circulation and 56 controls.All the patients were subjected to emboli-monitoring for 60 min using transcranial Doppler(TCD)within 72 h of stroke onset.Patients were classified into MES-positive and MES-negative groups according to the occurrence of MES.Stroke severity at admission was assessed by the National Institutes of Health Stroke Scale(NIHSS).Stroke patients were dividied into NIHSS Score≥6 and NIHSS Score<6 groups.Plasma OPG level of all the participants was measured by an enzyme-linked immunosorbent assay.Results Plasma OPG level was significantly higher in the LAA group than in the control group(1944.03 ± 604.76 vs 1371.17 ± 467.99pg/ml,p<0.001),higher in patients with an NIHSS score(≥ 6)than in those with an NIHSS score(<6)(2260.11±658.21 vs 1841.96±552.39 pg/ml,p=0.001),and higher in MES-positive compared to MES-negative patients(2357.13±513.24 vs 1804.88±570.70pg/ml,p<0.001).ROC curve analysis of OPG was used to determine the stroke severity,the results of which revealed an the area under the ROC curve(AUC)of 0.734 based on a cut-off value of 1998.44 pg/ml;The sensitivity and specificity of this test were 80.6% and 65.6%,respectively.Furthermore,if the levels of OPG was used to distinguish the presence of MES,the AUC was 0.766;the cut-off value was 2107.91 pg/ml.The sensitivity at this cut-off value was 68.8%,and the specificity was 73.7%.Conclusion Plasma OPG level was significantly associated with the stroke severity and the occurrence of microembolic signals.Plasma OPG level could be a useful biomarker for assessing the stroke severity and the occurrence of microembolic signals.