An Empirical Research On Interpersonal High Risk-stress Model Of College Students' Depression—longitude Tracking And VBM Analysis Of Brain Gray Matter Density Of MDD Patients

Part1Objective:(1) To investigate the roles of high-risk interpersonal factors, as well as stress, in the development of depression symptoms.(2) To test the model of high-risk interpersonal and stress theory of depression.Methods:628students from two universities in Changsha, Hunan of China participated in the longitudinal study for six times in half a year, with an interval of1month. All participants finished the Center for Epidemiological Studies Depression Scale, Network of Relationship Inventory and General Social and Academic Hassles Scale at Time1, and questionnaires assessing depression symptoms and stress level at each follow-up. Hierarchical Lineal Modeling (HLM) was used in data analysis.Results:(1) University students of different age did not vary in both their interpersonal support level and satisfaction (F=1.86, p>0.05/F=1.26, p>0.05). Independent sample t-test revealed female students had significantly higher interpersonal support than male students (18.54±8.70/15.10±8.94, p=0.0001), but no significant results on interpersonal support satisfaction (3.90±0.66/3.78±0.84, p>0.05)(2) HLM result showed:in prediction of depressive symptom in the university students'sample, there were main effect of stress level on first-time depression symptom scores (p<0.001), without Interpersonal supportx stress interaction. In both high interpersonal support group and low interpersonal support group, their depression symptom scores went along with the stress level (slope=0.12, t=4.94, P<0.001)(slope=0.07, t=2.94, P<0.01). But high group showed significantly smaller slope than low group of the line on stress level and depression symptoms (p<0.001).Conclusions:The association between the stress level and increases in depressive symptoms over time was moderated by interpersonal support satisfaction level. Part2Objective:Using the voxel-based morphometry (VBM) analysis, we examined the structural differences in whole brain gray matter density in major depressive disorder (MDD) vs. healthy participants, and explored the relationship between depression, stress and social support, to provide new clues and evidences for the understanding of the pathophysiologic mechanism in major depressive disorder.Methods:38patients with MDD and42healthy subjects participated in the MRI scans. The voxel-based morphometry was used to analyze characteristics of the whole brain gray matter density. Correlation analysis was made between gray matter density, CES-D, SHS and NRI.Results:(1) Compared with healthy controls, decreased gray matter density of right middle frontal gyrus, right superior frontal gyrus, left inferior frontal gyrus, left superior frontal gyrus, and increased right precuneus, left anterior central gyrus and right anterior cingulate were found in MDD group (p<0.001).(2) CES-D scores were positively correlated with the gray matter density of left medial frontal gyrus, negatively correlated with the right fusiform gyrus; SHS scores were positively correlated with left inferior frontal gyrus and cingulate, negatively correlated with left middle frontal gyrus; NRI scores were only negatively correlated with left inferior frontal gyrus, middle frontal gyrus, medial frontal gyrus, anterior central gyrus, precuneus, cingulate, fusiform gyrus, and parahippocampal gyrus.Conclusions:Patients with MDD had a structural brain abnormalities on grey matter density compared to healthy people, which is correlated with depression severity, stress and social support. This may be the pathological mechanism of the development of MDD.