Disrupted white matter integrity in first-episode, drug-naive, late-onset depression.
BACKGROUND
Abnormalities of white matter integrity in frontal and limbic regions have been postulated to play a key role in the pathophysiology of geriatric depression. However, there is no diffusion tensor imaging (DTI) study in patients with first-episode, drug-naive, late-onset depression (LOD). The aim of this study was to investigate whole-brain fractional anisotropy (FA) difference between patients with LOD and healthy controls without a previously determined region of interest.


METHODS
The sample included 15 patients with first-episode, drug-naive LOD and 15 age-, sex-, and education-matched healthy controls. The tract-based spatial statistics (TBSS) method was employed to analyze the DTI data.


RESULTS
Lower FA in the white matter of bilateral parahippocampal gyrus was observed in patients with LOD relative to healthy controls by voxel-wise statistics with the TBSS method. Patients did not have higher FA values in any brain regions compared to healthy controls. There was no correlation between the abnormal FA value in bilateral parahippocampal gyrus and depression severity or related factors.


CONCLUSIONS
The present study should be considered preliminary due to relatively small sample size.


CONCLUSIONS
Our findings suggest that loss of white matter integrity in parahippocampal gyrus may be associated with the pathophysiology of LOD, and thus highlight the limbic contribution to the pathophysiology of LOD.
Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China; Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China.
Wenbin
W
Guo
Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China.
Feng
F
Liu
Shandong Mental Health Center, Jinan, Shandong 250014, China.
Guanglei
G
Xun
Mental Hospital of Nanchang University & Mental Health Center of Jiangxi Province, Nanchang, Jiangxi 330029, China.
Maorong
M
Hu
Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China.
Xiaofeng
X
Guo
Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China.
Changqing
C
Xiao
Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China.
Huafu
H
Chen
Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China. Electronic address: chenjd269@163.com.
Jindong
J
Chen
Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China. Electronic address: edsgwb@126.com.
Jingping
J
Zhao
D017668:Age of Onset; D000368:Aged; D016880:Anisotropy; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D020534:Parahippocampal Gyrus / Q000473:pathology*
Diffusion tensor imaging; Late-onset depression; Tract-based spatial statistics; White matter