White matter characteristics between amygdala and prefrontal cortex underlie depressive tendency in end stage renal disease patients before the dialysis initiation.

Depression is one of the common incidental symptoms in end-stage renal disease (ESRD) patients, empirically overlooked. Reproducible results observed that altered interregional white matter (WM) connections between depression-related brain regions (thalamus, amygdala, and prefrontal cortex (PFC)) in the human brain were closely associated with depression. Whether the depressive tendency of ESRD patients is also association with the WM connections is remains unknown. To address this problem, 56 ESRD patients before dialysis initiation and 56 healthy controls (HCs) were scanned with diffusion tensor imaging. According to the diagnostic and statistical manual of mental disorders, ESRD patients were separated into with and without depressive tendency groups. Twenty-five essential metabolites were tested in ESRD. The tractography atlas-based analysis and multiple regression analysis were implemented to gain features which could map the depressive tendency variability across ESRD. For metabolites, the levels of thrombocytes and calcium have significant differences between with and without depressive tendency groups. For WM microstructure, depressive tendency ESRD patients had abnormal WM diffusion properties along the fiber tracts of the amygdala-PFC. Compared with the features which were extracted from the group-difference of WM or metabolites, only WM features combinations (1000 bootstrap samples; 5000 permutation tests) along the fiber tract of the amygdala-PFC was a significant predictor of either with or without depressive tendency. Our findings suggested that the advanced neuroprotection may be planned before dialysis initiation, and the WM characteristics of amygdala-PFC may be a potential neuromarkers for the early diagnosis of depressive tendency in ESRD patients before dialysis initiation.