A Study On The Identification Of Anxious/Unanxious Depression By Local Brain Activity In The Core Node Of The Default Mode Network Using Resting State Functional Magnetic Resonance

Objective: Anxious depression is the most common subtype of depression,which is characterized by severe depressive symptoms,low response to antidepressants and low clinical remission rate.The purpose of this study is to study the functional characteristics of the local brain area of the default mode network in anxious depression by resting functional magnetic resonance imaging(fMRI)and explore whether these abnormal imaging indexes can be used as neuroimaging markers to distinguish anxious depression from unanxious depression.Methods: First-episode and treatment-naive patients who met the diagnostic criteria for major depressive disorder according to the fourth edition of the Diagnostic and Statistical Manual ofMental Disorder(DSM-IV)were recruited to complete the study.The patients were divided into anxious depressive group and unanxious depressive group according to whether the anxiety/somatization factor score?7 in the 17-item Hamilton Depression Scale(HAMD-17);Healthy people with matching demographic characteristics served as the control group.All subjects underwent the resting state fMRI scans.The demographic data and clinical data of the patients were collected on the day of the scan.The brain imaging data of all subjects were conversion format,time-corrected,head motion-corrected and spatially standardized.After preprocessing,the imaging data were analyzed from the following aspects:(1)Regional homogeneity(ReHo)was used to explore the synchronization of local brain activity in anxious depression and unanxious depression.(2)Amplitude of low frequency fluctuation(ALFF)and fractional ALFF(fALFF)were used to investigate the intensity of spontaneous nerve activity in local brain regions in anxious depression and unanxious depression.Gender among the groups was tested by chi-square test.The one-way analysis of variance(ANOVA)was performed for the years of education and age.Independent two-sample t test was performed for duration and disease severity of the patients.ANOVA was conducted to compare whole brain ReHo,ALFF and fALFF in the three groups,which were followed by post-hoct-test.The ReHo?ALFF?fALFF values were corrected by multiple comparison correction by Alphasim method.The Pearson correlation analysis was performed between the ReHo,ALFF,fALFF values of the brain regions which showing significant difference in anxious/unanxious depressive group and the HAMD-17 total score,HAMD-17 factor score,Hamilton Anxiety Scale(HAMA)total score,course of disease.Each Pearson correlation values were corrected by multiple comparison correction by Bonferroni method.Receiver Operating Characteristic(ROC)statistical method was used to analyze the characteristic values of different brain regions between anxious depressive group and unanxious depressive group to generate the ROC curve.Results:(1).Features of resting state fMRI in anxious depression(1)Analysis of ReHo: Compared with the patients in the unanxious depressive group,the patients in the anxious depressive group displayed significantly lower ReHo values in the left inferior temporal gyrus,left middle temporal gyrusand right superior temporal gyrus.Compared with the subjects in the healthy control group,the patients in the anxious depressive group showed significantly lower ReHo values in the right cerebelum crus 2 and the right cerebellum 9.Relative to the subjects in the healthy control group,the patients in the unanxious depressive group exhibited significantly higher ReHo values in the left inferior temporal gyrus,left middle temporal gyrus and right middle temporal gyrus.(2)Analysis ofALFF:Compared with the patients in unanxious depressive group,the patients in the anxious depressive group displayed significantly lower ALFF values in the right orbital part of middle frontal gyrus.Compared with thesubjects in the healthy control group,the patients in the anxious depressive group showed significantly lower ALFF values in the right cerebelum crus2,right cerebelum crus1 and left cerebelum crus2;Relative to the subjects inthe healthy control group,the patients in unanxious depressive group exhibited significantly higher ALFF values in the right orbital part of middle frontal gyrus,and lower values in right inferior temporal gyrus,right cerebelum crus2,left cerebelum crus1 and left cerebelum crus2.There was negative correlation between the ALFF values of right orbital part of middle frontal gyrus and retardation factor scores in anxious depressive group(r=-0.37,p = 0.003).(3)Analysis of fALFF:Compared with the patients in unanxious depressive group,the patients in the anxious depressive group displayed significantly lower fALFF values in the right superior temporal gyrus.Compared with the subjects in the healthy control group,the patients in anxious depressive group showed significantly lower fALFF values in the right cerebelum 7b,right cerebelum 8,right cerebelum 9 and left cerebelum 9,and higher fALFF values in the left superior temporal gyrus.Relative to the subjects inthe healthy control group,the patients in unanxious depressive group exhibited significantly higher fALFF values in the left middle temporal gyrus,left superior temporal gyrus,right superior temporal gyrus and right cerebelum 4 ? 5.There was a positive correlation between the fALFF values in the right superior temporal gyrus and cognitive impairment factor scores in the anxious depressive group(r=0.36,p=0.005)(2)Identification of resting state functional magnetic resonance index in anxious/unanxious depression(1)Identification of specific brain region index in anxious/unanxious depression The sensitivity and specificity of the ALFF values in the right orbital parts of middle frontal gyrus,the fALFF values in the right superior temporal gyrus and the ReHo values in left inferior temporal gyrus,left middle temporal gyrus,right superior temporal gyrus which could identify anxious/unanxious depression were 42.1%,87.1%;63.2%,70.0%;76.3%,61.7%;60.5%,73.3%;5.3%,95.0%respectively.(2)Identification of combined index in anxious/unanxious depression After combining the index of the ALFF values in the right orbital parts of middle frontal gyrus,the fALFF values in the right superior temporal gyrus and the ReHo values in left inferior temporal gyrus,left middle temporal gyrus,right superior temporal gyrus,the sensitivity and specificity of identifying anxious/unanxious depression were 81.6%,80.0% respectively.Conclusion:(1)Anxious depression have dysfunction of some brain regions in DMN.(2)The combined index of these abnormal brain function characteristics in DMN can be used as a neurobiological marker to identify anxious/unanxious depression.