Study On Change Pattern Of Brain Spontaneous Activity On Resting-state FMRI In Maintenance Hemodialysis Patients With Sleep Disorder

Objective:The purpose of this research was to study on the change patterns of spontaneous activity of neurons in the brain of maintenance hemodialysis(MHD)patients with sleep disorder(SD)by resting-state fMRI,as well as analyse the correlation between the abnormal brain activity and clinical corresponding data,to exploring the possible brain injury and neuropathological mechanism of sleep disorder in MHD patients.Methods:Forty MHD patients were collected in hemodialysis center of our hospital from December 2016 to October 2018.According to the pittsburgh sleep quality index(PSQI)score,they were divided into two groups:SD group,n=20,including 13 males and 7 females,mean age 51.10±9.88 years old,the other was NSD group,n=20,including16 males and 4 females with an average age of 44.25±11.70 years old.22 healthy controls(HC group,16 males and 6 females,average age 51.77±10.85 years old)were recruited in the same period who match in age,sex and education years.All subjects were evaluated by Neuropsychological scale within 1 hour after undergoing MRI scan(Siemens3.0T MRI,Verio)which including 3D-T1 MPRAGE sequence and echo-planar imaging sequence.All patients completed the collection of blood biochemical parameters within 24hours before MRI scan.The change patterns of ReHo and ALFF of the whole brain resting fMRI in SD group were analyzed,and discussed the correlation between differential brain regions and clinical corresponding indexes.Statistical analysis were performed using the SPSS19.0.A p value lower than 0.05 indicated a statistically significant difference.Quantitative analysis of ReHo and ALFF values were executed by DPARSF toolkit on MATLAB 2013a platform,and we utilized AlphaSim multiple comparison to corrected the results.Results:The results of this study include the following three parts:1.General clinical data:there was no significant difference in demographic data(sex,age,education years)among the three groups in this study(P>0.05).Nevertheless,the scores of PSQI,TMT_A,SAS and SDS in SD group were significantly higher than those in HC and NSD groups(P<0.05).The scores of MOCA in SD and NSD groups were significantly lower than those in HC group(P<0.05).The serum potassium(K~+)in SD group was significantly higher than that in NSD group(P<0.05),but there was no significant difference in other blood biochemical indexes between SD and NSD groups(P>0.05).2.Value changes of ReHo and ALFF:compared with HC and NSD groups,the patterns of spontaneous activity and brain regions changes in SD group were as follows:the brain regions with significantly decreased ReHo or ALFF were mainly located in DMN and SCC while the parts of brain with increased ReHo values were located in cerebellum and temporal lobe.(cluster P<0.01,AlphaSim corrected).In NSD group,the brain area where the ALFF significantly decreased mainly were medial prefrontal cortex/anterior cingulate gyrus and posterior cingulate in comparison with HC group(cluster P<0.01,AlphaSim corrected).3.Correlation between value changes of ReHo and ALFF and clincal indexes:In SD group,the average ReHo value of patients in cerebellum(right cerebellar hemisphere and cerebellar vermis)was positively correlated with PSQI(r=0.490,P=0.046);The average ReHo value of left fusiform gyrus/inferior temporal gyrus was positively correlated with anxiety,depression and serum phosphours(r=0.626,P=0.007;r=0.721,P=0.001;r=0.528,P=0.030);The average ReHo value of right angular gyrus was negatively correlated with PSQI(r=-0.535,P=0.027),the average ALFF value in right angular gyrus was positively correlated with the depression scores(r=0.511,P=0.036).Conclusion:1.In patients of SD group,there are the spontaneous activity(ReHo and ALFF)of multiple brain areas in DMN decreased significantly,indicating that SD can aggravate the injury of the corresponding brain regions and lead to abnormal spontaneous activity,which may affect the cognitive function of MHD patients.Whlie the increase of ReHo value in emotion regulation-related brain areas might be an important mechanism for causing sleep disorders or aggravating emotion regulation disorders.2.The ReHo value of cerebellum was significantly higher than that of HC group,and the mean ReHo value of cerebellum was positively correlated with PSQI score,suggesting that cerebellum may be an imaging index to evaluate severity of sleep disorders in MHD patients.3.Both ReHo and ALFF methods found that the spontaneous activity of the right ANG decreased,and the ReHo value in the right ANG of patients was negatively correlated with PISQ,and the ALFF value in the right ANG was positively correlated with SDS,suggesting that abnormal spontaneous activity in the right ANG might be a sensitive imaging marker to evaluate the sleep quality and emotional disturbances of patients.