Influence of depression severity on interhemispheric functional integration: an analysis from the REST-meta-MDD...

Area of Science:

• Neuroimaging
• Psychiatry
• Brain Connectivity

Background:

• Major Depressive Disorder (MDD) significantly impacts daily functioning, necessitating accurate severity stratification for effective treatment.
• Resting-state functional magnetic resonance imaging (fMRI) offers potential neuroimaging biomarkers for MDD assessment.

Purpose of the Study:

• To evaluate voxel-mirrored homotopic connectivity (VMHC) as a neuroimaging biomarker for differentiating MDD severity.
• To investigate VMHC differences between mild-to-moderate and severe MDD patients and their correlation with depression scores.

Main Methods:

• Analysis of resting-state fMRI data from 392 first-episode MDD patients and 440 healthy controls (HC) from the REST-meta-MDD project.
• Classification of MDD patients into mild-to-moderate and severe groups using Hamilton Depression Scale (HAMD) scores.
• Examination of VMHC differences and correlation with HAMD scores, including Receiver Operating Characteristic (ROC) curve analysis.

Main Results:

• Significant VMHC reductions observed in the fusiform gyrus (mild-to-moderate MDD vs. HC) and extended to the insula, postcentral, and angular gyri (severe MDD).
• Increased VMHC in the middle cingulate cortex was found in severe MDD patients compared to mild-to-moderate MDD patients, positively correlating with HAMD scores.
• VMHC effectively differentiated MDD patients from HCs and across different depression severity levels.

Conclusions:

• VMHC serves as a promising neuroimaging biomarker for clinical diagnosis and stratification of MDD severity.
• Findings provide insights into the neurobiological underpinnings of MDD severity.