Association Between The Early-Onset Level And Variability Of Serum Potassium And Outcomes Of Continuous Ambulatory Peritoneal Dialysis Patients

Serum potassium abnormalities are universal in the peritoneal dialysis(PD)patients.Many previous reports found the risk factors and outcomes of hypokalemia in the PD patients.However,some problems about the potassium in the PD have never been revealed such as the rule of dynamic changes,association between the level or variability and outcomes of PD.In this condition,we design this clinical previous study.Aims:This single-center retrospective study focuses on the association between the early-onset level and variability of serum potassium and outcomes of continuous ambulatory peritoneal dialysis.Furthermore,we are able to establish reasonable and practical potassium controlling range for peritoneal dialysis patients.Methods:Among a total of 2248 patients initiated peritoneal dialysis,1278 eligible patients were enrolled in the study.Clinical serum potassium data were recorded in the initial,first,third and sixth month time point when patients enrolled the peritoneal dialysis.We divided patients according to the average serum potassium level or the fluctuation range:1,the average serum potassium grades:Grade 1:3.76mmol/L?K<4.26mmol/L;Grade 2:4.26mmol/L?K?4.77mmol/L;Grade 3:K<3.76mmol/L;Grade 4:K>4.77mmol/L;2,fluctuation range groups about serum potassium(Group 1-6).Variability Value is represented by standard deviation(RSS)and residual sum of squares(RSS).All-cause mortality,Cardio-vascular mortality,hemodialysis rate,transplantation rate were compared among 4 grades or 6 groups.Survival analysis was performed using the Kaplan-Meier Survival Curve and the Cox proportional hazards regression model.The results were expressed as the hazard ratio(HR)and the 95%confidence interval(95%CI).All statistical tests were two-sided,with a value for P<0.05 defined as significant.Results:By analyzing the data,the level of serum potassium remained stable and hypokalemia patients are 2 times or more than hyperkalemia ones when patients entered to the CAPD 1 month later.Four grades and six groups showed a significant survival difference nevertheless in the near-term or long-term follow-up course with exhibited lower cumulative survival rate in the Grade 3.Besides,group 4 and group 6 has a lower long-term survival comparing with the others.The increasing level of the serum potassium is an independent protective factor of all-cause mortality in the condition of K<4.26mmol/L.Grade 3,Group 4 and the increasing residual sum of squares(RSS)of the serum potassium is associated with higher all-cause mortality even after adjusting for potential confounding factors.Conclusion:Serum potassium abnormalities involving the level and stability contribute more to the death risk in PD patients.Grade 3,Group 4 or the increasing residual sum of squares of the serum potassium is an independent risk factor associated with higher all-cause mortality.The average level and fluctuation range of serum potassium provide an integrated assessment method with significant associations with prospective hospitalization and mortality in chronic PD patients and independently predict high risk of morbidity and mortality.