Levels Of Serum Potassium And Related Factors In Patients With Chronic Kidney Disease(CKD) In Different Stages

Objective:Chronic Kidney Disease(CKD)is a common disease that is harmful to human health,and influences the patient's quality of life and mental health.Disorders in Potassium homeostasis are one of the common effects of the chronic kidney disease that often lead to a variety of serious complications,and are even life-threatening.There are few studies comparing the level of serum potassium in patients at different stages of Chronic kidney disease(CKD).This study analyses the serum potassium levels and its related factors in different stages of CKD patient.Method: We made a retrospective study to analyse the serum potassium levels in different stages of CKD patients.We selected patients who were admitted in the nephrology department,from January 2011 to December 2015,of The Hospital of Da Lian Medical University for this study.Exclusion criteria included the following: Age < 18 years;acute kidney injury;trauma;hemolytic anemia;chemotherapy;Exercise Rhabdomyolysis;Regular dialysis patients.The stages of CKD is defined according to K/DOQI guidelines.According to the MDRD formula,e GFR was calculated and CKD was classified as:stage1: GFR?90 ml/(min·1.73m2);stage 2:60 ml/(min·1.73m2)?GFR <89 ml/(min·1.73m2);stage 3: 30 ml/(min·1.73m2)?GFR <59 ml/(min·1.73m2);stage 4:15 ml/(min·1.73m2)?GFR <29 ml/(min·1.73m2);stage 5: End-stage Renal Disease(ESRD):GFR<15 ml/(min·1.73m2)?The level of serum potassium: 3.5 mmol/L? K+ <5.5 mmol/L as the normal;K+? 5.5 mmol/L as hyperkalemia;K+<3.5 mmol/L as hypokalemia.Based on the level of serum potassium,three groups were created,mormokalemic group,hyperkalemia group and hypokalemia group.A total of 622 cases were finally selected.The patients' basic information: name;age;gender;pathology;whether patients were treated with ACEI/ARB,Beta blockers,potassium-sparing diuretic and non potassium–sparing diuretics.Clinical hematological parameters were also collected: serum creatinine(Scr);blood urea nitrogen(BUN);serum potassium(K+);carbon dioxide combining power(CO2CP).According to the CKD stages,the patients were subdivided into early CKD(CKD1~3 stages),late CKD(CKD4~5 stages).Result: 1.General information: In the study,622 cases were selected,348 cases were male(55.95%),female 274 cases(44.05%),age 18 to 91 years,mean age(57.10±16.10)years.Etiological classification of chronic kidney disease was as follows:Primary glomerular disease 250 cases(40.19%),diabetic nephropathy 177 cases(28.46%),hypertensive arteriolar nephrosclerosis 57 cases(9.16%),chronic interstitial nephritis 24 cases(3.86%),20 patients with polycystic kidney(3.22%),and hepatitis B associated nephritis 16 cases(2.57%),lupus nephritis 14 cases(2.25%),Henoch schonlein purpura 11 cases(1.77%),6 patients with obstructive nephropathy(0.96%),6 patients with gouty nephropathy(0.96%),ischemic nephropathy 3 cases(0.48%)and unknown etiology 27 cases(4.34%),others 11 cases(1.77%).In patients with chronic kidney disease,200 cases(32.15%)of patients with diabetes,152 cases(24.44%)of patients were treated with ACEI/ARB,115 cases(18.49%)of patients were treated with beta blockers,19 cases(3.05%)of patients were treated with potassium-sparing diuretic,42 cases(6.75%)of patients were treated with non potassium-sparing diuretics;The mean level of serum potassium was 4.35±0.77 mmol/L,the mean level of Scr 322.70±350.43 ?mol/L,the mean level of BUN 15.47±12.26 mmol/L,the mean level of e GFR 53.31±50.23 ml/(min?1.73m2),the mean level of CO2 CP 22.30±4.85 mmol/L.2.Serum potassium levels in CKD patients: The mean level of serum potassium in CKD patients was 4.35±0.77 mmol/L.Serum potassium for CKD1 stage was 4.04±0.35 mmol/L,serum potassium for CKD2 stage was 4.15±0.45 mmol/L,serum potassium for CKD3 stage was 4.19±0.62 mmol/L,serum potassium for CKD4 stage was 4.45±0.78 mmol/L,serum potassium for CKD5 stage was 4.67±0.98 mmol/L.Higher level of serum potassium was associated with the higher stages of CKD,especially in CKD4 ~ 5 stages.One–way analysis of variance statistical method was used to analyse the levels of serum potassium in CKD1 ~ 5 stages.In the early CKD,there were no statistical significant differences in the level of serum potassium amongthe three stages(P>0.05).And in the late CKD,there was also no statistical significant difference in the level of serum potassium between CKD 4 stage and CKD 5 stage(P>0.05).But there were statistical significant differences in serum potassium levels between the patients of CKD 4 stage and CKD 1 stage and between the patients of CKD 5 stage and CKD 1 stage respectively(P=0.000?P=0.000,P<0.01),moreover regarding the early and late CKD serum potassium levels,there was statistical significant difference between the two groups [(4.16±0.59 vs.4.59±0.83)mmol/L,P=0.002,P<0.01].3.The influence of serum potassium in different groups and drugs treatment: a)The serum potassium level of male patients was significantly higher than that of female ones in CKD1~5 stages[(4.40±0.81 vs.4.28±0.71)mmol/L,P=0.044,P<0.05].b)Serum potassium levels of the diabetes patients was significantly higher than the group without diabetes[(4.53±0.92 vs.4.28±0.69)mmol/L,P=0.001,P<0.01].In the diabetes,the late CKD serum potassium levels are significantly higher than the early CKD ones.[(4.71±0.97 vs.4.06±0.57)mmol/L,P=0.000,P<0.01].c)The levels of serum potassium between the patients who were on ACEI/ARB and those taking ACEI/ARB,had no significant difference [(4.31±0.71 vs.4.36±0.79)mmol/L,P=0.472,P > 0.05].In patients who were taking ACE/ARB,there was significant difference in the serum potassium in the early CKD compared to the late CKD,[(4.16±0.59 vs.4.58±0.83)mmol/L,P=0.002,P<0.01].d)The levels of serum potassium between the patients who were taking beta-blockers and not taking beta-blockers had statistical significant difference [(4.58±0.96 vs.4.30±0.71)mmol/L,P=0.004,P<0.01],In patients who were taking beta-blockers,there was significant difference in the serum potassium in the early CKD compared to the late CKD,[4.08±0.56 vs.4.75±1.01)mmol/L,P=0.001,P<0.01].e)The levels of serum potassium between the patients who were taking potassium-sparing diuretic and not taking potassium-sparing diuretic had statistical significant difference too [(4.58±0.96 vs.4.30±0.71)mmol/L,P=0.004,P<0.01].f)The levels of serum potassium between the patients who were taking non potassium sparing diuretics and not taking non potassium sparing diuretics hadstatistical significant difference [(4.48±0.89 vs.4.34±0.76)mmol/L,P=0.242,P>0.05].4.Incidence of the serum potassium disbalance in chronic kidney disease patients(Hyperkalemia and hypokalemia): a)The incidence of hyperkalemia: There was no occurrence of hyperkalemia in the CKD1 stage and CKD2 stage.The incidence of CKD3 ~ 5 stages of hyperkalemia were 4.60%(4/87),9.33%(7/75),18.39%(41/223)respectively.Using the chi-square test to compared the incidence of hyperkalemia between early and late CKD,the results showed that the incidence of hyperkalemia between the two groups was statistical significant difference(P=0.000,P<0.01).b)The incidence of hypokalemia: The incidence of hypokalemia in CKD1 ~ 5 stages were 5.49%(9/164)?9.59%(7/73)?9.20%(8/87)?9.33%(7/75)?10.31%(23/223)respectively.Using the chi-square test to compare the incidence of hypokalemia among the CKD1 ~ 5 stages,it was found out that there was no significant difference(P>0.05).c)Based on the level of serum potassium the patients were divided into 3 groups: mormokalemic,hyperkalemia and hypokalemia.Analysing the related parameters of the three groups by one-way analysis of variance,we found out that the e GFR,Scr,BUN,and CO2 CP had statistical significance differences among the three groups(P=0.000?P=0.000?P=0.000?P=0.002,P<0.01).The e GFR,Scr,BUN,CO2 CP were statistical significant different in the hyperkalemia group compared to the normokalemic group(P=0.000?P=0.000?P=0.000?P=0.000,P<0.01).The e GFR?Scr and CO2 CP had statistical significant differences in the hypokalemia group compared to the normokalemic group(P=0.015?P=0.009?P=0.031,P<0.05).5.The level of serum potassium in CKD patients and its related factors.The serum potassium level in CKD patients was shown to have a significant correlation with whether or not they were taking ACEI/ARB,whether or not they were taking potassium sparing diuretics,gender,Scr,BUN,CO2 CP,e GFR(P<0.01).It was found out that CO2 CP,e GFR and female gender had a negative correlation with serum potassium levels(r=-0.083,0.373,0.312 respectively,P<0.05).The intake of beta-blockers and potassium-sparing diuretics,Scr,BUN had a positive correlation with serum potassium levels(r=0.142,0.107,0.300,0.387 respectively,P<0.01).Conclusion: 1.Higher level of serum potassium was associated with higher stages of CKD,especially in CKD4 ~ 5 stages,where the incidence of hyperkalemia is significantly higher.2.In CKD patients,the male are more prone to factors of hyperkalemia.Use of beta-blockers and potassium-sparing diuretic will cause hyperkalemia,and the patients of CKD4~5 stages will be more prone to hyperkalemia than the patients of CKD1~3 stages who were treated with beta-blockers;The patients who taking row of potassium diuretics may not cause potassium disorders.The patients of CKD4~5 stages will be more prone to hyperkalemia than the patients of CKD1~3 stages who were treated with ACEI/ARB;Diabetes patients compared to non-diabetes patients are more prone to hyperkalemia,CKD4 ~ 5 stages diabetes patients are more likely to develop hyperkalemia compared to CKD1~3 stages.