Correlation Between Cognitive Dysfunction And Cerebral Iron Deposition In Patients With Maintenance Peritoneal Dialysis

Objective: To study the correlation between cerebral iron deposition and cognitive dysfunction in CKD patients undergoing maintenance peritoneal dialysis,and to provide theoretical basis for clinical diagnosis and treatment of cognitive dysfunction in CKD patients.Methods:(1)30 healthy physical examinations were selected from outpatient clinics of Affiliated Hospital of Youjiang Medical College for Nationalities as a healthy control group(group A).90 patients with chronic kidney disease(CKD)stage5 were enrolled into the study.The general clinical data(sex,age,BMI,smoking history,primary disease,age at dialysis)and laboratory indicators(WBC,Hb,RBC,platelets,Scr,BUN,β2-MG,Cys-C,ALB,SF,SI,Zn,Ca,P,Vitamin D3,CRP,i PTH,TG,TC,HDL,LDL,VLDL,etc.)were recorded for all participants.(2)Serum of CKD patients was collected,and serum total iron binding capacity(TIBC)was detected by ELISA.Then TAST of CKD patients was calculated,and the patients were divided into group D(TAST ≥ 20%),group E(TAST < 20%,SF≥100 ug/L),group F group(TAST < 20%,SF < 100 ug/L).(3)Head MRI scan was performed,and each Magnetic Susceptibility Value(MSV)of deep gray matter nuclei was determined by quantitative magnetic susceptibility map for analysis and comparison.(4)Montreal Cognitive Assessment(Mo CA)was used to measure cognitive function of patients with CKD,and they were divided into group B(score <26,patients without cognitive impairment)and group C(score ≥ 26,patients with cognitive impairment).(5)All clinical data and test results were statistically analyzed.Results:(1)Compared with chronic kidney disease group,Hb,RBC,RDW-SD,platelet/lymphocyte,albumin,serum iron and TAST in healthy control group were higher than those in chronic kidney group.RDW-CV,neutrophil/lymphocyte,β-microglobulin,cystatin C,serum creatinine,urea nitrogen,ferritin,TIBC and CRP in healthy control group were lower than those in chronic kidney group(P < 0.05),and the difference was statistically significant.The Hb difference between iron sufficient group and absolute iron deficiency group was statistically significant.Compared with functional iron deficiency group,neutrophil/lymphocyte value in absolute iron deficiency group was higher(P=0.043),and the difference was statistically significant.The serum iron and ferritin of absolute iron deficiency group were significantly different from those of iron sufficiency group(P < 0.05),and the difference was statistically significant.Pairwise comparison of TIBC and TSAT showed that there were significant differences between functional and absolute iron deficiency groups and iron sufficiency groups(P < 0.05).(2)The brain iron content in the left and right caudate nucleus and the left and right substantia nigra of chronic kidney disease group and normal control group was significantly higher than that in normal control group,the difference was statistically significant(P < 0.05).There was no significant difference in iron content between chronic kidney disease group and normal control group in the left and right pallidus pallidus,left and right putamen and left and right red nucleus(P > 0.05).There was no significant difference in the left and right magnetic sensitivity values of each brain region(caudate nucleus,globus pallidus,putamen,red nucleus,substantia nigra)between cognitive impairment group,non-cognitive impairment group and normal control group(P > 0.05).Conclusion:(1)The iron metabolism in MPD patients is abnormal,and the content of iron deposition inbrain tissue is significantly increased than that in healthy people.(2)Cognitive dysfunctionin MPD patients is associated with iron deposition in brain tissue.