Alteration of brain functional connectivity strength in patients with type 2 diabetes and its neuropathological mechanism / 解放军医学杂志

ABSTRACT

Objective To explore the change of brain functional connectivity strength in patients with type 2 diabetes mellitus(T2DM)and its neuropathological mechanism.Methods Fifty-six T2DM patients who visited Gansu Provincial Hospital from October 2017 to March 2021 were selected as T2DM group,and 48 healthy controls were selected as control group.A prospective study was conducted on the changes in brain function in T2DM patients by analysis of resting state functional connectivity strength(FCS)and functional connectivity(FC)based on seed points.Brain functional magnetic resonance imaging,clinical variable collection,and neuropsychological testing of patients in two groups were performed.We calculate the FCS value,evaluate the brain function changes of the two groups in the resting state,take the brain regions with significant differences between the groups as the seed points and perform functional connectivity analysis with the whole brain.Correlation analysis was conducted between the FCS,FC values of the different brain regions and clinical variables such as fasting blood glucose(FPG),glycosylated hemoglobin(HbA1c),thyroid hormone(TSH)levels,as well as the scores of mini mental state examination(MMSE),Montreal cognitive assessment(MoCA),clock drawing test(CDT),Hamilton Depression Rating Scale(HAMD-24)and Hamilton Anxiety Scale(HAMA).Results Compared with control group,the HAMD-24 and HAMA scores in T2DM group significantly increased(P<0.01),while the MoCA scores decreased(P<0.05);In T2DM group,the FCS value of the right middle temporal gyrus increased(GRF correction,voxel level P<0.001,clustering level P<0.05),and the FC value of the right middle temporal gyrus-left anterior cingulate cortex decreased(GRF correction,voxel level P<0.001,clustering level P<0.05).Correlation analysis showed that the FC value of right middle temporal gyrus-left anterior cingulate cortex in T2DM patients was negatively correlated with HAMD-24 score(r=-0.395,P=0.003),HbA1c level(r=-0.303,P=0.023),and positively correlated with TSH level(r=0.324,P=0.017).Conclusions The increase of FCS value in the right middle temporal gyrus and the decrease of FC value in the right middle temporal gyrus-left anterior cingulate cortex may be important neuroimaging features of brain function damage in T2DM patients.HbA1c may play an important role in the process of brain damage in T2DM patients.