Research On The Impact Of Dialysis Modality On Cognitive Function And Relationship Of Serum BDNF Levels And Cognitive Function

Objective: Our aim is to assess the cognitive function of dialysis patients, discusswhether dialysis modality can affect cognitive function, and analyze the causes to allow forspecific treatment. We also want to test the patients’ serum levels of BDNF in order to findnew clinical indicators for cognitive impairment to improve the diagnosis and treatment ofcognitive impairment.Methods:80ESRD patients underwent maintenance dialysis in nephrologydepartment of the Second Affiliated Hospital of Soochow University from June2011through January2012, including40cases of peritoneal dialysis (PD group),40patientswith hemodialysis (HD group) and40control cases hospitalized for chronic kidneydisease with a eGFR>60ml/min/1.73m2(CKD group). There are no significantdifferences in age, sex, education among these three groups. The MoCA questionnaire wasused to assess the cognitive function of all Subjects. Serum biochemical, electrolyte, PTH,and clotting series, etc were tested based on an empty stomach. Serum BDNF levels wasdetermined with ELISA test. Statistics were carried out using SPSS17.0statisticalsoftware package, while P <0.05is considered statistically significant.Results:1. MoCA score in PD group and HD group are significantly lower than incontrol group, while PD group show significantly higher MoCA score than the HD group.2. Serum BDNF levels are significantly lower in both PD group and HD group，compared with in control group. Serum BDNF levels in PD group is lower than in HDgroups, although there is no statistically significance.3. There is significant positive correlation between Serum BDNF levels and MoCA score (r=0.422, P <0.01).4. MoCA score is correlated with age, length of education, and the residual renalfunction in PD group, while serum BDNF levels is correlated with the length of educationand serum PTH levels.5. In HD group, MoCA score is correlated with age, length of education, low densitylipoprotein cholesterol and urea reduction ratio (URR), while BDNF levels show nocorrelation with the demographic and clinical data.Conclusion:1. Cognitive impairment is prevalent in ESRD patients, PD can improve cognitivefunction through protection of the residual renal function and amelioration of thehemodynamic impairment.2. BDNF is a sensitive marker of the cognitive impairment index, can serve as apractical biochemical marker for evaluation of cognitive impairment in clinicalassessments.3. Protection of residue renal function In PD patients and more sufficienthemodialysis in HD patients may be promising strategies to delay in cognitive decline.