MRI study identifies shared cortical patterns across depression and physical diseases

Major depressive disorder commonly co-occurs with physical illnesses, but the brain features potentially shared across these conditions are not well defined. Researchers analyzed multimodal MRI data from 577 patients with major depressive disorder, asthma, fibromyalgia, gastroesophageal reflux disease or type 2 diabetes, alongside 275 healthy controls. They constructed individual morphometric similarity networks to assess cortical patterns and used molecular and cognitive mapping to explore their correlates.

All patient groups showed regional network abnormalities. A shared pattern involved increased similarity in visual and somatomotor regions and decreased similarity in ventral attention, limbic and default mode networks. The pattern was replicated in independent cohorts. Its spatial distribution was associated with gene-expression signatures related to synaptic signaling, membrane-potential regulation and neuronal architecture, with predominant expression in excitatory and inhibitory neurons and astrocytes. The authors also reported associations with neurotransmitter-system maps and overlap between related genes and known Alzheimer’s disease and bipolar disorder risk loci.

The findings offer a research framework for investigating shared mechanisms across depression and physical illness, but do not establish causation or a diagnostic or treatment application. Cognitive decoding was exploratory, and the reported molecular relationships are spatial associations. The supplied abstract does not provide further detail on the independent replication cohorts or subgroup sizes.