Trait-like white matter abnormalities in current and remitted depression.

Area of Science:

• Neuroimaging
• Psychiatry
• Neuroscience

Background:

• White matter (WM) microstructural alterations are associated with the onset and recurrence of major depressive disorder (MDD).
• Understanding trait-like WM abnormalities is crucial for identifying biological markers of MDD.
• Previous research suggests WM integrity may be compromised in individuals with MDD.

Purpose of the Study:

• To identify trait-like white matter (WM) abnormalities in individuals with current major depressive disorder (MDD) and remitted MDD.
• To investigate WM changes specifically related to the state of clinical remission in MDD.
• To explore the neuroanatomical underpinnings of MDD using diffusion tensor imaging.

Main Methods:

• Diffusion tensor imaging (DTI) data were acquired from three groups: medication-naive first-episode current MDD (cMDD), medication-naive remitted MDD (rMDD), and healthy controls (HCs).
• Tract-based spatial statistics (TBSS) were employed for whole-brain analysis to detect microstructural differences in WM among the groups.
• Fractional anisotropy (FA) values were analyzed to quantify WM integrity.

Main Results:

• Both cMDD and rMDD groups showed significantly reduced FA values in the corpus callosum and corona radiata compared to HCs.
• No significant differences in FA values were found between the cMDD and rMDD groups.
• In the rMDD group, FA values in the corpus callosum were negatively correlated with the duration of illness.

Conclusions:

• Reduced white matter (WM) integrity in the corpus callosum and corona radiata may represent trait markers for major depressive disorder (MDD).
• These WM abnormalities could serve as a neuroanatomical marker for MDD, persisting even after clinical remission.
• The findings suggest that WM alterations are fundamental to MDD pathophysiology, independent of the current depressive state.