Risk Factors For Cerebral Microbleeds And The Correlation Between Cerebral Microbleeds And Cognitive Function In Patients With Acute Ischemic Stroke

Part one Risk factors for cerebral microbleeds in patients with acute ischemic strokeObjective: To investigate the related risk factors of cerebral microbleeds?CMBs?in patients with acute ischemic stroke?AIS?.Methods: A total of 226 consecutive inpatients with AIS from our department between January 2014 and December 2015 were chosen in our study.Based on the occurrence of CMBs,the patients were divided into two groups?111 patients with CMBs;115 patients without CMBs?.The demographic and clinical data were collected.MR imagings were performed in all the patients.CMBs were counted respectively according to their locations.The number of old lacunar infarcts?LI?and the severity of white matter lesions?WML?were also recorded.Then,logistic regression analysis,?² test,T-test and so on were used to analyze the related risk factors of CMBs in patients with AIS.Results:1 The overall prevalence of CMBs in patients with AIS was 49.1%,44.0% with first-ever AIS and 59.2% with recurrent AIS in this study.The most common location of CMBs in patients with AIS was the lobar regions?64.9%?,followed by the deep regions?58.6%?,and the infratentorial regions?39.6%?.The cases of CMBs from grade 0 to grade 3 were 115?50.9%?,73?32.3%?,21?9.3%?,17?7.5%?.2 Two hundred twenty-six patients with a diagnosis of AIS were included.The CMBs group included a higher age,a higher prevalence of hypertension,antiplatelet use,previous history of stroke,a greater number of old LI,and more severe WML compared with the group without CMBs?P<0.05?.The fasting blood-glucose and proportion of hyperlipemia,total cholesterol,triglyceride,very low density lipoprotein were lower in patients with CMBs than in those without CMBs?P<0.05?.3 The multivariate logistic regression analysis showed that the age?OR=1.063,95%CI:1.025¹.104;P<0.01?,hypertension?OR=3.488,95%CI:1.113¹0.927,P<0.05?,WML?OR=1.282,95%CI:1.155¹.423;P<0.01?and old LI?OR=5.815,95%CI:1.539²1.973,P<0.01?were all the independent risk factors for CMBs in patients with AIS.4 The Spearman's rank correlation analysis suggested that the grade of CMBs was positively correlated with the grade of WML??s=0.354,P<0.01?as well as the grade of old LI??s =0.394,P<0.01?.The linear trend test indicated that the grade of CMBs was linearly with the grade of WML(?²_linear=35.07,P<0.01;?²_nolinear=14.07,P>0.05)as well as the grade of old LI(?²_linear=37.88,P<0.01;?²_nolinear=6.01,P>0.05).Part two Correlation between cerebral microbleeds and the lesion location or subtype of AISObjective: To explore the relationship between between CMBs and the lesion location as well as the correlation between CMBs and AIS mechanism.Methods: After evaluating risk factors of CMBs,AIS mechanism was classified into small-vessel occlusion,large-vessel atherosclerosis and other subtype?cardioembolism,stroke of other determined cause and stroke of undetermined cause?according to the TOAST criteria.The lesion locations were classified into infratentorial,deep,lobar and multiple lesion.The ?² test and Kruskal-Wallis H were used to analyze the relationship between CMBs and the lesion location as well as the correlation between CMBs and AIS mechanism.Results:1 The prevalence of CMBs was 51.1%?24/47?in infratentorial stroke lesion,45.1%?23/51?in deep stroke lesion,49.2%?30/61?in lobar stroke lesion and 50.7%?34/67?in multiple stroke lesion.No differences were statistically significant between them?P>0.05?.There was also no correlation between the location of CMBs and lesion in AIS?P>0.05?.2 The prevalence of CMBs was 59.3%?54/91?in small-vessel occlusion,40.0%?32/80?in large-vessel atherosclerosis and 45.5%?25/55?in other subtype.The correlation between CMBs and AIS mechanism were compared and the difference between them were significant?P<0.05?.Compared between any two groups,the difference were significant?P<0.05?between small-vessel occlusion and large-vessel atherosclerosis.There were no statistically significant differences?P>0.05?between other subtype and small-vessel occlusion or large-vessel atherosclerosis.3 The Kruskal-Wallis H test showed that the difference between the severity of CMBs and AIS mechanism were significant?P<0.05?.Compared between any two groups,the difference were significant?P<0.05?between small-vessel occlusion and large-vessel atherosclerosis.There were no statistically significant differences?P>0.05?between other subtype and small-vessel occlusion or large-vessel atherosclerosis.Part three The influence of cerebral microbleeds on post-stroke cognitive impairmentObjective: To observe the influence of CMBs and dynamic change of CMBs on post-stroke cognitive impairment?PSCI?.Methods: A group of 20 CMBs patients were randomly selected from the first part in our study.After selecting the CMBs patients,a control group of 30 patients were selected from the group without CMBs in the first part,on the basis of their group similarity to the 20 patients with CMBs on the following criteria: distribution of age,gender,years of education,severity of WML,the number of old LI,stroke lesion location and stroke subtype.A detailed neuropsychological assessment and the repeated susceptibility weighted imaging were made after 1 follow-up year.Results:1 The two groups were well matched for distribution of age,gender,years of education,severity of WML,the number of old LI,stroke lesion location and stroke subtype?P>0.5?.2 Compared with the control group,the time of TMTb was longer inpatients with CMBs?P<0.05?.There was no signifcant difference?P>0.05?between the CMB and non-CMB groups in the other neuropsychological assessments.3 The prevalence of CMBs was 64%?32/50?after 1 year.Compared with the control group,only executive impairment was more prevalent in CMBs group?P<0.05?.There was no signifcant difference?P>0.05?between the CMBs and non-CMBs groups in the proportion impaired in the other cognitive domains at the 1-year follow-up.4 In unadjusted binary logistic regression,executive impairment was associated with the age?OR=1.11,95%CI:1.01¹.23;P<0.05?,presence of baseline CMBs?OR=3.5,95%CI:1.05¹1.7,P<0.05?,and any new CMBs at follow-up?OR=3.8,95%CI:1.09¹3.3,P<0.05?.Conclusion:1 The age,hypertension,WML and old LI were all the independent risk factors for CMBs in patients with AIS.2 The more severe of WML or LI,the more severe of CMBs.3 CMBs were more common in small-vessel occlusion.4 CMBs were more severe in small-vessel occlusion.5 Executive impairment was most common in post-stroke cognitive impairment at 1-year follow-up.6 In AIS patients,baseline CMBs were associated with executive impairment at follow-up after 1 years.7 The age,presence of baseline CMBs and any new CMBs at follow-up might be the risk factors for the executive impairment at follow-up after 1years.