Functional Magnetic Resonance Imaging Study Of Abnormal Waist-to-height Ratio In Type 2 Diabetes Mellitus

Objectives:Patients with Type 2 diabetes mellitus may have cognitive impairment in earlier stage.Obesity,especially abdominal obesity,is also a risk factor for cognitive impairment.Type 2 diabetes mellitus with overweight/obesity is common.Overweight and obesity can seriously affect the control of blood sugar and metabolism in type 2 diabetes mellitus.At present,there are few studies about how dose overweight/obesity work on the brain of type 2 diabetes mellitus patients.We believe that waist to height ratio could reflect the level of visceral fat and discriminate obesity-related cardiometabolic risk better.In this study,ALFF(Amplitude of Low-Frequency Fluctuations)based on resting magnetic resonance functional sequence was used to analyze the brains of type 2 diabetic subjects which were devided to healthy,overweight,very overweight and obese using the weist to high ratio standard,and whether different degrees of overweight/obesity had effects on the brains of type 2 diabetic patients was explored.Method:According to the selection criteria,76 patients diagnosed as T2DM were selected as the case group in the Endocrinology out-patient department and In-patient department of The First Affiliated Hospital of Kunming Medical University from November 2017 to November 2018.In the end two subjects were excluded because of the image quality.According to waist to height ratio,patients were divided into four groups:G1,G2,G3 and G4.Group G1 was normal type 2 diabetes group,group G2 was overweight type 2 diabetes group,group G3 was very overweight type 2 diabetes group,and group G4 was obese type 2 diabetes group.Meanwhile,30 healthy volunteers with matched sex,age,education years,waist to height ratio,normal blood sugar and normal plasma triglyceride.All the subjects were measured waist to height ratio,blood pressure,and tested the level of glycated hemoglobin(HbA1c),fasting blood glucose,plasma triglyceride test,and underwent T2WI,BOLD sequence of brain using Silent GE 3.0 T magnetic resonance scanner.The data were processed by MRICron software,MATLAB software,DPABI software and DPARSF software.ANCOVA analysis and double-sample t-test were used to analyze the ALFF values in the intergroup.The ALFF values with statistic difference and clinical data were compared and analyzed by SPSS software,and the correlation analysis and multivariate linear statistical analysis were performed.Results:(1)There were statistic difference between HC group and G1 group.The ALFF values of right cerebellum 6 lobes,right anterior cerebellum and right fusiform increased in G1 group,but there was no correlation between the ALFF values and clinical data.(2)There was no statistic difference between G1 group and G2 group.(3)There were statistic differences between the two groups:the ALFF values of the right fusiform and the right parahippocampal gyrus increased in the G3 group,but there was no correlation between the ALFF values and clinical data.(4)There were statistic differences between G3 group and G4 group.The ALFF values of right cerebellum Crus2 area,right fusiform,right cerebellum 6 lobes,right anterior cerebellum,right parahippocampal gyrus and right hippocampus decreased in G4 group,but there was no significant correlation with clinical data.(5)There were statistic differences between HC group and G2 group.The ALFF values of right cerebellum 6 lobes,right anterior cerebellum,right temporal lobe and right fusiform increased in G2 group.The correlation analysis showed that waist to height ratio,the value of HbAlc and fasting blood sugar were weakly and positively correlated with statistically different ALFF values.(6)There were statistic differences between the G1 group and the G3 group.The ALFF values of the right cerebellum Crus2 area,the right fusiform,the right cerebellum 6 lobes,the right anterior cerebellum and the right parahippocampal gyrus increased in the G3 group.There were statistic differences in ALFF values between the groups.The correlation analysis showed that the waist to height ratio was moderately positively correlated with statistically different ALFF values ALFF values.(7)There was statistic difference between G2 group and G4 group in ALFF values.Compared with G2 group,the ALFF values of 6 lobes of right cerebellum,anterior lobe of right cerebellum and spindle gyrus of right cerebellum were decreased in G4 group.The correlation analysis showed that waist to height ratio was moderately negatively correlated with statistically different ALFF values.(8)There were statistic differences between HC group and G3 group.The ALFF values of right cerebellum Crus2 area,right fusiform,right cerebellum 6 lobes,right anterior cerebellum,right parahippocampal gyrus and right hippocampus increased in G3 group.The correlation analysis showed that waist to height ratio,the value of HbA1c were moderately correlated with ALFF values.(9)There was no statistic difference between G1 group and G4 group.(10)There was no statistic difference between HC group and G4 group.Conclusions:The value of HbA1c and waist to height ratio are correlated with the changes of ALFF values in right cerebellum,right fusiform,right hippocampus and right parahippocampal gyrus,and the correlation has some regularity.When the waist-to-height ratio is overweight,the correlation between HbA1c and abnormal brain area of ALFF value is greater.With the increase of waist-to-height ratio,the correlation between the waist-to-height ratio and abnormal brain area of ALFF value is gradually enhanced and surpasses that of HbAlc,and the abnormal brain area of ALFF value is gradually increased.