The Study For The Change Of CMBs-related Memory Function And Resting-state Brain Function In T2DM With CMBs

Purpose:Diabetes is associated with impaired cognitive functioning and an increased risk of dementia. Diabetes Metabolic disturbance and related micro vascular disease are major causes of impaired cognitive function. The studies for abnormal brain imaging in Type2diabetes mellitus (T2DM) patients is mainly focused on both white matter hyperintensities (WMH) and lacuna infarct so far, however, the study on cerebral microbleeds (CMBs) has been rarely reported. In this study, we used memory scale and functional magnetic resonance imaging (fMRI) methods to investigate whether CMBs will have influence on the T2DM patient’s cognitive function and resting-state brain function, Which can provide vascular aspects for cognitive function in T2DM and brain damage as well as early identification of clinical vascular risk factors and to give timely clinical interventions to improve cognitive function to prevent the development of vascular dementia.Methods:92consecutive patients with T2DM were collected for trial in the third xiangya hospital of central south university from August2012to August2013.They were fulfilled with the prognostic standard of American Diabetes Association2009. According to the SWI results, the subjects were divided into2groups:one group with T2DM with cerebral microbleeds (19men,13women), while the other group without cerebral microbleeds (26men,29women).All subjects were examed by coginitive Scale. The Beck Depression Inventory was used for screening to exclude depression. All subjects valuated the cognitive function by MoCA and WMS to compare and analyze the differences of the total scores of cognitive function and scores of different cognitive domains in patients with or without cerebral microbleeds. Meanwhile, All the patients’chemical and clinical data were detailed noted. The two group were matched in the age、BMI、the year of education and biochemistry-related material. All the patients were examed by traditional magnetic resonance imaging、Functional Magnetic Resonance Imaging and susceptibility weighted imaging. white matter hyperintensities、 Lacunar infarction and cerebral microbleeds were observed. By fMRI analysis、functional-connectivity analysis and ALFF analysis, we get abnormal brain areas in type2diabetes mellitus patients. At last, we made correlation analysis between abnormal brain areas and impaired cognition function.Results:1Among all patients, the CMBs positive was observed in34patients while the CMBs negative was observed in58patients. The incidence rate was36.96%.2Cognitive function:When Compared with the patients who had no CMBs, the scores of WMS memory quotient, working memory and short-time memory was lower in type2diabetes mellitus patients with CMBs.(P<0.05)3Functional connectivity:We carried out analysis between bilateral hippocampal and all other volexs to determine the regions with low-frequency fluctuations that and correlated with it. The results showed that hippocampus showed reduced functional connectivity bilaterally to widespread regions, including left Temporal Pole, left superior temporal gyrus, right anterior cingulate gyrus and right Precentral Gyrus in type2diabetes mellitus patients with CMBs compared to type2diabetes mellitus patients without CMBs. Moreover, the functional connectivity between left hippocampal and left superior temporal gyrus were found to be positively related to short-term memory (imagination) in type2diabetes mellitus with CMBs group(r=0.29, p=0.034), and the functional connectivity between right hippocampal and right anterior cingulate gyrus were found to be positively related to working-memory (WMS1-100) in type2diabetes mellitus with CMBs group(r=0.25, p=0.039).4Two-sample t-test analysis, type2diabetes mellitus with CMBs patients had significantly decreased ALFF values in the left superior frontal gyrus; whereas increased ALFF values were observed in left superior temporal Gyrus、both the bilateral cerebellum posterior lobe and the right Insula. Further more the ALFF value in the left superior temporal Gyrus was found to be correlated positively with total memory (WMS memory quotient core)(r=0.26, p=0.045) Conclusions:The overall score in terms of memory and reduce short-term memory in T2DM patients with CMBs indicated CMBs was associated with cognitive impairment.1.In the resting-state, the functional connectivity between hippocampal and other brain regions and low frequency amplitude value changed in type2diabetes mellitus with CMBs, reflecting CMBs have negative effects on brain function in patients with type2diabetes.2.The change of cognitive function and resting state brain function in T2DM with CMBs, which somewhat explains the pathogenesis of cognitive function impairment of type2diabetes mellitus from vascular factors.This also provides some evidences for judging the condition of cognitive function impairment of type2diabetes mellitus and provides reference for early recognition of vascular risk factors which gives early clinical intervention in order to prevent the development of vascular dementia.