Study Of The Cognitive Fluctuations And Resting-state MRI Brain Injury In Hemodialysis Patients With End-stage Renal Disease

Objective:To explore the abnormal intrinsic brain activity in patients with end-stage renal disease?ESRD?undergoing maintenance hemodialysis?MHD?at intervals of 1and 24 hours after hemodialysis session by using regional homogeneity?ReHo?and amplitude of low frequency fluctuation?ALFF?algorithm,and analyze the correlation between altered ReHo,ALFF and cognitive tests,laboratory indexes,to explore the possible pathological mechanisms of MHD related cognitive fluctuation and brain injury in patients with ESRD.Materials and methods:A total twenty-one MHD patients and 21 HC subjects were recruited from Affiliated Zhongshan Hospital of Dalian University during October 2016 to December 2017.The study was approved by the ethics committee of the Affiliated Zhongshan Hospital of Dalian University,written informed consents were obtained from all of the subjects.All participants were right-handed and the age ranges from 25 to 70 years old.All participants who had contraindications of MR scan,alcohol or drug abuse,contraindications of tests,visual impairment,physical dysfunction,brain infarction or tumor,neurological or psychiatric disease et al.were excluded from our study.MHD subjects were excluded if the dialysis duration is less than 3 months.General informations were recorded.All participants accepted cognitive tests,including MoCA et al.MHD patients' laboratorial indexes were recorded within 1 hour after dialysis.All participants accepted MRI scan,including 3DT1 WI,T2FLAIR and rs-fMRI scan.Matlab was used to analyze the ReHo and ALFF differences between MHD group and HC.Two-sample t test was preformed to investigate the whole-brain ReHo and ALFF differences between MHD and HC,P values less than 0.001 was considered as statistically significant.Paired t test was used to investigate the ReHo and ALFF differences of MHD group?Within 1 hour and 24 hour after dialysis?,P values less than 0.05 was considered to be statistically significant.Correlation analysis was used to analyze the correlations between ReHo or ALFF and cognitive tests scores or laboratory tests values,P<0.01 were considered to be statistically significant.Results:1.Demographic and clinical characteristics: significant TMT_A score and MoCA score differences were observed between MHD and HC groups?P<0.05 corrected?.The TMT_A score was significant differences between MHDT1 and MHDT2 group?P<0.001 corrected?.2.Compared to HC group,ReHo were decreased in the right superior temporal gyrus,ALFF values were decreased in the right calcarine,increased in the left cerebellum₈ in MHDT2 group?P<0.001 corrected?.Compared to MHDT1 group,ReHo values were increased in the right temporal gyrus in MHDT2 group?P<0.05 corrected?,ALFF values were increased in the right fusiform gyrus.3.Correlation analysis: There was not significant correlation between ReHo values of difference regions?MHDT1 vs MHDT2 group?and the scores of various laboratory indexes,cognitive scores?P > 0.05 corrected?.Correlation analysis revealed that multiple laboratory indicators and cognitive scores were mainly correlated with the ReHo and ALFF values of one or more brain regions in the default mode network?DMN?region in MHDT1 group?P<0.01 corrected?.Conclusion:1.There were cognitive fluctuation?improvement of executive function?between MHDT1 and MHDT2 groups,which shows enhanced local coherence of neuro-activity in right temporal gyrus.2.MHD patients mainly manifested as cognitive impairment in temporal lobe,frontal lobe and parietal lobe.Compared to MHDT2 group,MHDT1 group revealed that cognitive impairment were much worse in the right temporal lobe,bilateral occipital lobe.Hemodialysis and secondary response to dialysis may be the main influencing factors for the cognitive injury.3.ReHo and ALFF algorithm can be used to detect and evaluate the fluctuation of the short-term spontaneous neuron activity and cognitive fluctuation in MHD patients.