Altered spontaneous brain activity in patients with progressive-stage and end-stage chronic kidney disease: insights from dALFF analysis

Chronic kidney disease (CKD) is a worldwide public health problem. Its association with cognitive impairment has attracted widespread attention in the world. However, the neuropathological mechanisms underlying kidney-brain interactions in CKD remain unclear. Using the dynamic amplitude of low-frequency fluctuations (dALFF) technique, 21 patients with progressive-stage CKD (CKD stages 3-4), 22 patients with end-stage CKD (CKD stage 5, ESKD), and 23 healthy volunteers (HCs) were enrolled to explore the brain regions with dALFF abnormalities in the progressive-stage and end-stage CKD. We used biased correlation analyses to explore the relationship between dALFF values and clinical indicators in patients with progressive-stage and end-stage CKD. Patients with both progressive-stage CKD (stages 3-4) and ESKD had abnormal dALFF values in the right parahippocampus, right inferior temporal gyrus, and left cuneus compared with HCs. In addition, abnormal dALFF were present in the left fusiform gyrus, insula and hippocampus in patients with progressive-stage CKD and in the left inferior temporal gyrus in patients with ESKD. Biased correlation analysis showed that dALFF values in the right parahippocampus, left fusiform gyrus and left insula were positively correlated with serum creatinine concentrations in patients with progressive-stage CKD and that dALFF values in the left inferior temporal gyrus were negatively correlated with MoCA scores in patients with ESKD. Our findings highlight the variability of neuroimaging changes between different stages of CKD and provide new insights and research directions for an in-depth exploration of the neuropathological mechanisms of renal-brain interactions.