Gray matter atrophy is constrained by normal structural brain network architecture in depression.

Area of Science:

• Neuroscience
• Neuroimaging
• Psychiatry

Background:

• Growing evidence suggests brain network architecture constrains gray matter atrophy in neuropsychiatric disorders.
• This relationship remains unexplored in individuals with depression.
• This study investigates the link between gray matter atrophy and connectome architecture in depression.

Purpose of the Study:

• To investigate the association between gray matter atrophy and normal connectome architecture at an individual level in depression.
• To identify disease epicenters and understand their role in the pathological progression of depression.

Main Methods:

• Utilized two independent Chinese datasets with 297 patients with depression and 256 healthy controls (HCs).
• Assessed individualized regional atrophy using a normative model.
• Identified putative disease epicenters by matching structural connectome profiles in HCs to atrophy patterns via stepwise regression analysis.

Main Results:

• Connectome architecture of identified epicenters explained 44% (±16%) of gray matter atrophy variance.
• Shared disease epicenters in depression included the hippocampus, thalamus, and medial frontal gyrus, showing higher participation coefficients.
• Brain regions structurally connected to epicenters exhibited greater vulnerability, and two subgroups with different onset ages were identified.

Conclusions:

• Gray matter atrophy in depression is constrained by the structural brain connectome.
• Findings elucidate potential pathological progression pathways in depression.
• Highlights the role of specific brain regions and network architecture in depressive disorders.