Correlations of Expression Levels of microRNA-206 and microRNA-186 in the Serum With Disease Severity and Prognosis of Elderly Patients With Vascular Dementia

Objective To investigate the correlations of the expression levels of microRNA (miR)-206 and miR-186 in the serum with the disease severity and prognosis of elderly patients with vascular dementia (VD). Methods A total of 104 elderly patients with VD treated in Dalian Municipal Central Hospital from October 2020 to May 2023 were selected into the VD group and 104 healthy volunteers who underwent physical examinations were enrolled in the control group.Baseline data of both groups were collected,and fluorescence quantitative PCR was used to measure the expression levels of miR-206 and miR-186 in the serum.According to the severity of VD,the patients were assigned into mild,moderate,and severe VD groups.The elderly patients with VD were followed up for 6 months after discharge.According to the prognosis,the patients were assigned into good/moderate and poor prognosis groups.The baseline data and the serum levels of miR-206 and miR-186 were compared between the control and VD groups as well as between the good/moderate and poor prognosis groups.The serum levels of miR-206 and miR-186 were compared between the mild,moderate,and severe VD groups.The correlations of serum miR-206 and miR-186 levels with mini-mental state examination (MMSE) score in elderly patients with VD were analyzed,on the basis of which the factors affecting the poor prognosis of elderly patients with VD were predicated.Furthermore,the predictive values of serum levels of miR-206 and miR-186 on the poor prognosis of elderly patients with VD were evaluated. Results The VD group had higher proportions of diabetes history (P=0.021),hypertension history (P<0.001),and hyperlipidemia history (P<0.001),higher serum levels of miR-206 (P<0.001) and miR-186 (P<0.001),and lower score of activity of daily living (P<0.001) than the control group.The serum miR-206 and miR-186 levels varied between the mild,moderate,and severe VD groups (all P<0.001).The trend test results showed that serum miR-206 and miR-186 levels presented a rising trend in mild,moderate,and severe VD groups (all P<0.001).The serum miR-206 and miR-186 levels in elderly VD patients were negatively correlated with the MMSE score (all P<0.001).The poor prognosis group had lower MMSE score and higher serum levels of miR-206 and miR-186 than the good/moderate prognosis group (all P<0.001).The MMSE score was a protective factor and miR-206 and miR-186 were risk factors for poor prognosis in elderly patients with VD (P=0.005,P=0.001,P=0.007).The area under curve of combined serum miR-206 and miR-186 levels in predicting poor prognosis in the elderly patients with VD was 0.963,which was higher than those (0.866 and 0.878) of serum miR-206 and miR-186 levels separately (P=0.010,P=0.020). Conclusions The serum levels of miR-206 and miR-186 in elderly patients of VD are high and closely related to the severity and prognosis of VD.The combination of the two demonstrates high performance in predicting the prognosis of elderly patients with VD.