Objective:To investigate the prognostic value of serum levels of miR-134 and miR-146b in elderly patients with acute ischemic stroke(AIS).Methods:A total of 162 elderly patients with AIS admitted to the Third People's Hospital of Haikou from January 2017 to October 2019 were enrolled.According to modified Rankin Scale(mRS)scores, they were divided into the good prognosis group(n=98, mRS score≤2)and the poor prognosis group(n=64, mRS score>2). Based on the National Institutes of Health Stroke Scale(NIHSS), patients were divide into the mild group(n=46, NIHSS score<5), moderate group(n=75, 5≤NIHSS score≤20), and severe group(n=41, NIHSS score>20). Real-time fluorescence quantitative PCR was used to detect serum levels of miR-134 and miR-146b in each group.Multivariate logistic regression was used to analyze risk factors for poor prognosis in elderly patients with AIS.The receiver operating characteristic(ROC)curve was used to analyze the value of serum miR-134 and miR-146b levels in predicting poor prognosis of elderly patients with AIS.Pearson correlation was used to analyze the correlations of serum levels of miR-134 and miR-146b with NIHSS and mRS scores in elderly patients with AIS.Results:Serum levels of miR-134(3.26±1.13 vs.0.85±0.38)and miR-146b(2.27±0.93 vs.0.56±0.21)were higher in the AIS group than in the control group( t=14.360 and 12.527, P<0.01). Serum levels of miR-134(4.35±1.46 vs.2.28±0.85)and miR-146b(3.07±1.04 vs.1.51±0.66)were higher in the poor prognosis group than in the good prognosis group( t=13.520 and 11.242, P<0.01). Serum levels of miR-134 and miR-146b in the severe group were higher than in the moderate and mild groups( t=10.815 and 9.462, P<0.01), and they were also higher in the moderate group than in the mild group( t=13.627, 11.611, P<0.01). Multivariate Logistic regression analysis showed that serum miR-134( OR=2.470, 95% CI: 1.603-4.927)and miR-146b( OR=1.914, 95% CI: 1.350-3.406)were risk factors for poor prognosis in elderly AIS patients( P<0.05). The ROC curve analysis showed that the optimal cut-off values of serum miR-134 and miR-146b to predict poor prognosis in elderly AIS patients were 3.84 and 2.68, respectively.The area under the ROC curve(AUC)of combined serum miR-134 and miR-146b(0.926, 95% CI: 0.865-0.987)for the prediction of poor prognosis was higher than that of either marker alone, with a sensitivity and specificity of 92.4% and 86.2%, respectively.The correlation analysis showed that serum levels of miR-134 and miR-146b were positively correlated with NIHSS and mRS scores in elderly AIS patients( r=0.806, 0.871, 0.785 and 0.842, all P<0.01). Conclusions:Increased serum miR-134 and miR-146b levels are correlated with the severity of neurological impairment and prognosis in elderly patients with AIS.Serum miR-134 and miR-146b levels together have a high value in predicting poor prognosis in elderly AIS patients.