White Matter Microstructural Abnormalities And Its Related Cognitive Function Changes In End-stage Renal Disease:A Diffusion Tensor Image(DTI)Study

Background:End-stage renal disease(ESRD)is a serious public health problem,which can often lead to multiorgan dysfunction,such as cerebrovascular disease and cognitive damage.It is essential to understand cognitive impairment in patients with ESRD to develop better ESRD treatment and prevent further cognitive impairment.Cognitive impairment is believed to be related to structural abnormalities in the brain.Diffusion tensor imaging(DTI)can detect microstructural changes of the white matter(WM)in ESRD patients.Fraction anisotropy(FA),mean diffusivity(MD),axial diffusivity(AD)and radial diffusivity(RD)are the DTI parameters that can be used to evaluate WM microstructural integrity in detail.Purpose:To investigate white matter microstructural abnormalities in patients with ESRD using TBSS analysis of DTI and to explore the possible mechanisms underlying the impaired cognitive function.Materials and Methods:This study was approved by the research ethics committee of Guangdong Second Provincial General Hospital and all participants provided informed consent.We performed a TBSS analysis of DTI data collected from 35 neurologically asymptomatic patients with ESRD and 40 age-and gender-matched healthy controls(HCs)to investigate the microstructural changes in their WM over the whole brain.Moreover,Pearson's correlations were performed between clinical indicators and WM regions of decreased FA value in ESRD patients.Results:lower FA and higher MD AD and RD were observed in widespread and symmetrical WM in ESRD patients than HCs,Pearson correlation analysis revealed a significantly positive correlation between the Mini-Mental State Examination(MMSE),digit span test scores and FA values in the left anterior thalamic radiation(p<0.01)and demonstrated a significantly negative correlation between FA values and the serum creatinine and blood urea nitrogen in the anterior thalamic radiation(p<0.01).There was no correlation between FA values and hemodialysis duration and disease duration.Conclusion:The results in our study indicated widespread impairment of the white matter in ESRD patients.Damage to the thalamic radiation and corona radiata may damage the default mode network and central executive network respectly and so affect cognitive function in ESRD patients.Demyelination and axonal injury may both lead to WM impairment in ESRD patients,and accumulation of serum creatinine and blood urea nitrogen may contribute to this impairment.