Changes Of White Matter In Young And Middle-aged Patients With End-stage Renal Disease Undergoing Maintenance Hemodialysis:A Diffusion Tensor Image(DTI)Study

Purpose:To study white matter microstructural abnormalities in young and middle-aged patients with end-stage renal disease(ESRD)undergoing maintenance hemodialysis using diffusion tensor imaging(DTI),and to further explore the relationship between the microstructural alterations of white matter and cognitive function and clinical biochemical indexes.Methods:The DTI imaging data of 21 young and middle-aged ESRD maintenance hemodialysis patients and 21 age-and gender-matched healthy controls(HC)were collected.All subjects underwent neuropsychological tests,including Montreal Cognitive Assessment(MoCA)and Mini-Mental State Examination(MMSE),and collected relevant laboratory data of ESRD patients(including hemoglobin,serum creatinine,blood urea nitrogen and blood calcium).The differences of neuropsychological tests and sub-MoCA scores between the two groups were compared.tract-based spatial statistics(TBSS)was used to analyze the DTI data,and the differences of fractional anisotropy(FA),mean diffusivity(MD),axial diffusivity(AD)and radial diffusivity(RD)between the two groups were compared.We also explored the correlations of the FA and AD values with significant differences in white matter with cognitive function,dialysis time and laboratory examination of ESRD patients.Results:There were significant differences in MoCA and MMSE scores between ESRD group and HC group.Compared with HC group,sub-MoCA scores including visuospatial and executive and delayed recall in ESRD group were decreased(P<0.05).The FA values of multiple symmetrical white matter areas in ESRD group were lower than those in HC group,mainly in the forceps minor,bilateral inferior fronto-occipital fasciculus,inferior longitudinal fasciculus and corticospinal tract(TFCE correction,P<0.05).In ESRD group,the AD value of some white matter areas increased,mainly in the forceps minor,right inferior fronto-occipital fasciculus,left superior longitudinal fasciculus,left corticospinal tract and forceps major(TFCE correction,P<0.05).The values of MD and RD in almost all white matter areas in ESRD group were higher than those in HC group(TFCE correction,P<0.05).Pearson correlation analysis showed that only the FA value of forceps minor was positively correlated with MoCA and MMSE in patients with ESRD(P<0.05).The FA value of forceps minor was negatively correlated with the dialysis time(P<0.05).The FA value of bilateral inferior fronto-occipital fasciculus was negatively correlated with blood urea nitrogen(P<0.05).There was no significant correlation between FA,AD value and serum creatinine,hemoglobin and serum calcium in white matter difference brain regions between the two groups(P<0.05).Conclusion:TBSS analysis method of DTI can be used to detect the microstructural changes of white matter in young and middle-aged patients with ESRD maintenance hemodialysis,and to clarify the possible neuropathophysiological mechanism of cognitive impairment in ESRD patients.Blood urea nitrogen may be a risk factor for white matter damage in ESRD.