Diffusion Tensor Imaging Study Of Major Depressive Disorder Patients With Insomnia Symptoms

Background:Major depressive disorder(MDD)is widely prevalent throughout the world,and symptoms often include depression,loss of pleasure,loss of interest,abnormal weight gain or loss,and decreased energy,etc.In severe cases,suicidal tendencies may occur,ranking among the top psychiatric diseases.Many patients often present with somatic symptoms as the chief complaint.Insomnia is a common physical symptom in patients with MDD,and often appears as the first symptom.Studies show that about 92% of patients with MDD have sleep disorder,among which85.2% of patients with MDD have insomnia,most of the patients are difficult to fall asleep,wake up early,and wake up repeatedly.Previous studies have shown that patients with MDD with sleep problems have complex clinical symptoms,enhanced suicidal ideation,and aggravated cognitive impairment.Therefore,there is a complex relationship between MDD and insomnia symptoms,but the current research on the mechanism of MDD accompanied by insomnia symptoms is not sufficient,and the conclusions of existing studies are low in homogeneity.Diffusion tensor imaging(DTI),as an important part of neuroimaging,has been gradually applied to explore the neuropathological mechanism of psychiatric diseases.Can therefore be collected with the insomnia patients with MDD,is not associated with insomnia in patients with MDD and healthy participants of diffusion tensor imaging,explore with MDD neuroimaging mechanism of insomnia,further explore the structure of white matter fiber tracts of anomaly and the correlation between clinical features.Methods: Based on inclusion and exclusion criteria,60 first-episode patients with MDD who had not received medication and 30 contemporaneous healthy participants were recruited for demographic matching.The sleep quality and insomnia symptoms of 60 patients were evaluated by Pittsburgh Sleep Quality Index(PSQI).According to the evaluation results,patients with MDD were divided into group with insomnia symptoms(30 cases)and group without insomnia symptoms(30 cases).Participants were assessed for Depression using the Hamilton Depression Scale 24(HAMD-24).The Beck Scale for Suicide Ideation-Chinese Version(BSI-CV)was used to assess participants’ suicidal ideation.Participants’ cognitive functioning was assessed using the Repeatable Battery for the Assessment of Neuropsyehological Status(RBANS) Tests.All participants received DTI image scanning based on JHU white-matter tractography atlas and Tract-based spatial statistics(TBSS).Fractional anisotropy(FA)was used as index to obtain the structural integrity of 20 white matter fibers.Ftest was performed on the data of the three groups of participants to obtain significantly different white matter fiber tracts,which were subsequently examined postmoratally to identify abnormal structural fiber tracts in the group with insomnia symptoms.Finally,the correlation between FA value of abnormal fiber bundles and clinical scale score was analyzed.Results: In this study,the Corticospinal tract R(CST＿R)FA value was increased in participants with insomnia symptoms in the whole white matter bundle compared with healthy controls.Inferior fronto-occipital fasciculus R(IFOF＿R),Forceps minor(FMi),Anterior thalamic radiation R(ATR＿R)FA value decreased;Compared with the group without insomnia symptoms,the Inferior longitudinal fasciculus L(ILF＿L),Anterior thalamic radiation L(ATR＿L)showed decreased FA values,but no increased FA values were found.White matter change is closely related to clinical symptoms of patients,among which CST＿R is related to cognitive function of patients with insomnia symptoms,ATR＿L is related to homicidal ideation of patients with insomnia symptoms.Conclusion:The structure of white matter fiber bundles in patients with MDD with insomnia is abnormal,mainly including CST＿R,IFOF＿R,FMi,ATR＿R,ILF＿L and ATR＿L.These changes in white matter fiber fascicles may be related to the neuropathological mechanism of MDD with insomnia symptoms.At the same time,the structural integrity of CST＿R is related to the cognitive function of patients,and the structural integrity of ATR＿L is related to the suicidal ideation of patients.This study provides new evidence for the cause of insomnia MDD from the perspective of neurophysiology.