Resting-state functional connectome correlates of suicide attempt history and childhood trauma in major depressive disorder.

BACKGROUND

A prior suicide attempt is the strongest predictor of subsequent suicide mortality in major depressive disorder (MDD); however, the functional network architecture distinguishing individuals with and without a history of suicide attempts remains incompletely characterized. We applied a connectome-wide functional connectivity (FC) framework to identify FC alterations associated with suicide attempt history in MDD and examine their relationships with suicidal ideation and childhood trauma.

METHODS

Resting-state functional magnetic resonance imaging data were obtained from 204 participants (suicidal depression [SD] = 61, non-suicidal depression [NSD] = 62, healthy controls [HC] = 81). FC matrices were constructed using the Schaefer 400-node atlas. Group differences were examined using network-based statistics (NBS) and graph-theoretical measures.

RESULTS

NBS identified a significant subnetwork exhibiting lower FC in the SD group than in the NSD group (pFWE = 0.038), spanning the visual (VIS), somatomotor (SMN), dorsal attention (DAN), frontoparietal (FPN), and default mode (DMN) networks. Compared with the HC group, the SD group exhibited hypo- and hyperconnected subnetworks, whereas the NSD group showed no significant differences in FC. Graph-theoretical analyses revealed reduced strength, global efficiency, and betweenness centrality within the SD < NSD subnetwork. In the MDD group, mean subnetwork FC, SMN-VIS, and DMN-DMN FC were negatively correlated with suicidal ideation. In the SD group, SMN-SMN FC correlated inversely with childhood sexual abuse.

CONCLUSIONS

These findings suggest that hypoconnectivity across sensory, attentional, and self-referential systems may represent a connectome-level signature of suicide vulnerability in MDD and link childhood sexual abuse to suicide risk.