Altered spontaneous brain activities in maintenance hemodialysis patients with cognitive dysfunction and the construction of cognitive function prediction models

Abstract

Abstract Trial registration:The study was approved by the Ethics Committee of the Second People's Hospital of Changzhou City (KY032-01). OBJECTIVE: To measure changes in spontaneous brain activity in maintenance hemodialysis patients (MHD) with cognitive impairment (CI) base on resting-state functional magnetic resonance imaging (rs-fMRI) and predict cognitive function in maintenance hemodialysis patients by combining spontaneous brain activity and clinical indicators. METHODS: We selected 50 patients undergoing maintenance hemodialysis at the Second People's Hospital of Changzhou City from September 2020 to December 2021; 28 healthy volunteers were recruited during the same period, and all subjects underwent neuropsychological testing and rs-fMRI. MHD patients were divided into MHD-CI group and MHD-NCI group according to neuropsychological testing score. Data analysis was performed after image preprocessing to explore spontaneous brain activity changes in differential brain regions of MHD-CI patients and to analyze the correlation between spontaneous brain activity and clinical variables. Back propagation neural network (BPNN) was used to predict cognitive function. RESULTS: Compared with the MHD-NCI group, the patients with MHD-CI had more severe anemia and higher urea nitrogen levels, the lower mALFF values in the left postcentral gyrus, lower mfALFF values in the left inferior temporal gyrus, and greater mALFF values in the right caudate nucleus (p < 0.05). Correlation analysis showed that the mALFF values in the left postcentral gyrus of MHD patients were significantly positively correlated with hemoglobin levels (r = 0.551, p = 0.000) and MOCA scores (r = 0.457, p = 0.001), negatively correlated with urea nitrogen (r = –0.519, p = 0.000). left temporal inferior gyrus mfALFF values were significantly negatively correlated with urea nitrogen levels (r = –0.523, p = 0.000) and positively correlated with MOCA scores (r = 0.295, p = 0.038). The right caudate nucleus mALFF values were negatively correlated with MOCA scores (r = -0.455, p = 0.001). Based on quantifiable influencing factors, we construct different BPNN prediction models, indicating that the diagnostic efficacy of the model which inputs were hemoglobin, urea nitrogen and mALFF value in the left central posterior gyrus is optimal(R2=0.8054). CONCLUSION: In summary, the left inferior temporal gyrus and left postcentral gyrus might be the critical regions affecting cognitive function in MHD-CI patients, and correction of anemia and adjustment of urea nitrogen levels might help prevent CI in MHD patients. Combined with rs-fMRI not only reveals the neurophysiological mechanism of cognitive impairment, but also can serves as a neuroimaging marker for the diagnosis and evaluation of cognitive impairment in patients with MHD.