Resting Functional Connectivity Of Amygdala Before And After Treatment In Adolescents With First-episode Depression

BackgroundMajor depressive disorder(MDD)is a mood disorders that characterized by depression and/or loss of interest or pleasure.MDD has aroused the concern of the whole society because its morbidity,recurrence,suicide,disability and medical service occupancy rate.Studies of MDD showed that the incidence rate of childhood was about 2.8%,and increased to 5.6% in adolescence.Early-onset MDD patients have poor prognosis and are prone to recurrence and depressive symptoms can continue into adulthood.In recent years,functional magnetic resonance imaging(fMRI)has become one of the hotspots in the study of MDD.Magnetic resonance studies of adult depression have found abnormalities in brain function and structure.brain function structures of adolescent MDD patients are also abnormal,there are still differences changes between adolescent MDD and adult MDD in brain function and structure.Studies have shown that puberty developmental changes affect the pathophysiology of MDD in adolescents,and the pathophysiology between adolescent MDD and adult MDD is still different.Therefore,studying the pathogenesis of MDD in adolescents has important clinical significance for the diagnosis,treatment and prognosis of MDD.Objective1.To investigate the changes of resting brain function in the amygdala of adolescents with first-episode MDD;2.To investigate the changes of resting brain functional connectivity in the amygdala of adolescents with first-episode MDD after treatment.MethodsThe sixteen adolescent first-episode MDD patients with DSM-5 diagnostic criteria were enrolled as subjects,a case-control study was conducted,sixteen adolescent healthy control groups(HCs)matched with age,sex and years of education were selected as controls.Resting functional magnetic resonance(fMRI)scans were performed.The bilateral amygdala was selected regions of interests(ROI)to analyze the functional connections between amygdala and whole brain regions.To compare the difference of functional connectivity between patients and healthy controls,and to compare the difference of functional connectivity between patients after 8 weeks of SSRIs treatment and before treatment.To explore the changes of resting functional connectivity of amygdala between patients and healthy controls and patient group before and after treatment.Results1.The functional connections between left amygdala and bilateral superior temporal gyrus,right cingulate gyrus and right hippocampus in MDD group were enhanced compared with the control group;the functional connections between right amygdala and left superior temporal gyrus,anterior cuneiform lobe,right superior marginal gyrus and left olfactory cortex in depression group were enhanced compared with the control group(p<0.05 with AlphaSim correction).2.The functional connections between left amygdala and bilateral middle temporal gyrus,left posterior central gyrus and left middle frontal gyrus in depression group were enhanced after treatment;the functional connections between right amygdala and right middle temporal gyrus,left inferior occipital gyrus,right middle frontal gyrus,right posterior central gyrus and right superior occipital gyrus in depression group were enhanced after treatment(p<0.05 with AlphaSim correction).Conclusions1.There are abnormal changes in amygdala functional connectivity in adolescents with first-episode MDD before treatment.Abnormal amygdala functional connectivity may be one of the pathogenesis of MDD.2.After antidepressant treatment,the amygdala-brain functional connectivity in adolescents with first-episode depression changed compared with that before treatment,and the depressive symptoms of adolescents were significantly improved.The amygdala functional connectivity can be used as a potential marker of antidepressant treatment.