White matter abnormalities in first-episode patients with major depressive disorder

Objective The aim of this study was to explore the microstruetural integrity of whole brain white matter with diffusion tensor imaging(DTI)in patients with major depressive disorder(MDD). Methods Fourteen first-episode,medication-nave young adult patients with MDD and 14 matched healthy controls received DTI scan,then were analyzed by voxel-based analysis.Results The patients showed significantly lower fractional anisotropy(FA)values than healthy controls in the white matter of the fight middle frontal gyrus(x=36,y=49,z=10;t=4.89,cluster=258),left lateral occipitotemporal gyrus (x=-42,y=-56,z=-1;t=5.00,cluster=96),and the angular gyrus(x=24,y=-47,z=41; t=5.23,cluster=120)and sub-gyral(x=42,y=-65,z=27;t=4.56,cluster=76)in right parietal lobe(P0.001).There were no significant correlations between the FA value in any brain area and depressive severity as well as illness course.Furthermore,compared with healthy controls,no regions with significantly higher FA values were found in patients with MDD.Conclusion These findings suggest that abnormalities of brain white matter may be actually present early in the course of MDD and support that white matter lesions which disrupt the neural circuits may be involved in mood regulation.