Disrupted functional connectivity of the amygdala is associated with depressive mood in type 2 diabetes patients.

BACKGROUND

Type 2 diabetes mellitus (T2DM) and mood disorders share pathophysiological commonalities in the central nervous system. The purpose of this study was to investigate the alterations in amygdala-based emotional processing circuits in T2DM patients with depressive mood using resting-state functional magnetic resonance imaging (rs-fMRI).

METHODS

T2DM patients with depressive mood (n = 25), T2DM patients without depressive mood (n = 28) and matched healthy controls (n = 25) underwent neuropsychological testing and rs-fMRI scanning. A seed-based correlation analysis was conducted to reveal the altered functional connectivity (FC) of the amygdala. The bilateral amygdala FC was compared among the three groups. Pearson correlation analyses were performed in a voxel-wise manner to investigate the relationship between amygdala FC and the clinical characteristics.

RESULTS

The depressed T2DM patients exhibited the worst performance on the neuropsychological tests among the three groups. Compared to the non-depressed T2DM patients, the depressed T2DM patients showed decreased amygdala FC in the cingulate cortex, inferior frontal gyrus, fusiform gyrus, and precentral gyrus. Moreover, the amygdala FC in the cingulate cortex was associated with the Self-Rating Depression Scale (SDS) score in the T2DM patients.

LIMITATIONS: Cross-sectional design.

CONCLUSIONS

The current study revealed the cognitive changes and alterations in the amygdala-cingulate functional disconnections in T2DM patients with depressive mood, which will advance the understanding of the neural mechanisms underlying depression in T2DM patients.