Correlation Analysis Of Early Glucose Exposure And Peritoneal Dialysis Associated Peritonitis In Peritoneal Dialysis

BackgroundPeritoneal dialysis(PD)is an effective alternative treatment for end-stage renal disease(ESRD).It has been widely used in the world,especially in developing countries,because of its advantages of stable hemodynamics,effective delay of the decline of residual renal function(RRF),good removal effect of middle molecular toxins,low risk of infectious diseases,advantages of health economics and home treatment.According to a global survey,more than 272,000 people worldwide are receiving PD,accounting for 11%of the total number of dialysis patients,and growing at an annual rate of 8%.Statistics showed that there were 40,000 patients in China at the end of 2012,an increase of 10 times compared with 2000.However,the policies of different countries and regions on PD,complications of PD,ultrafiltration failure and peritoneal dialysis fluid and many other issues affect the further promotion of PD.In order to further improve the utilization rate of PD in ESRD patients,it is necessary to understand the roots for limiting the use of PD and reducing the duration of PD treatment.Therefore,clinicians need to master the precautions of PD treatment and the prevention and treatment of related complications,so as to minimize the possibility of PD patients turning to hemodialysis(HD),thus greatly promoting the development of PD.Peritoneal dialysis associated peritonitis(PDAP)is one of the most common complications of PD,which is closely related to hospitalization,ultrafiltration failure,conversion to hemodialysis,increased cost of treatment and mortality.PDAP is also an indicator of Standardised Outcomes in Nephrology-Peritoneal Dialysis(SONG-PD).Previous studies have identified the effects of variable risk factors(malnutrition,use of immunosuppressive drugs,patient training,etc)and immutable risk factors(age,gender,diabetes,residual renal function,race,etc)on PDAP.In clinical studies,it is controversial whether the high glucose environment of peritoneal dialysis fluid is a risk factor for PDAP.Previous studies on the relationship between PD glucose exposure and PDAP have yielded different results.Some studies suggest that there is no significant correlation between glucose exposure and PDAP,but other studies have shown that high glucose exposure is associated with high recurrence rate of PDAP.Therefore,it is of great clinical significance to study the relationship between glucose exposure and PDAP.ObjectiveAt present,there are different results on the relationship between glucose exposure and peritoneal dialysis related peritonitis.Therefore,this study retrospectively analyzed the clinical data of peritoneal dialysis patients who were regularly followed up in the Nephrology Hospital of the First Affiliated Hospital of Zhengzhou University,and explored the relationship between glucose exposure and the risk of PDAP to provide reference for clinical peritoneal dialysis treatment.Methods1.Research objectTotal 374 patients underwent peritoneal dialysis tube implantation and received PD treatment in the Nephrology Hospital of the First Affiliated Hospital of Zhengzhou University between January 1,2015 and December 31,2018.Exclusion criterion included that(1)age<18 years old;(2)patients with automated peritoneal dialysis;(3)patients who did not follow the doctor’s advice for standardized treatment;(4)no follow-up examination or follow-up period less than 3 months;(5)PD treatment time was less than 3 months;(6)PDAP occurred within 6 weeks after PD treatment;(7)complicated with systemic infectious diseases(including hepatitis,syphilis,gonorrhea,etc.);(8)complicated with malignant tumor.The end points included that(1)death;(2)transfer to HD;(3)kidney transplantation;(4)transfer to other centers;(5)end of follow-up(December 31,2019).2.Research methodDemographic and anthropometric characteristics of the studied patients were collected,including age,gender,body mass index(BMI),systolic blood pressure(SBP),duration of follow-up of PD,educational level,history of primary kidney disease,diabetes,hypertension,cardiovascular disease,etc.Clinical parameters measured at 6 weeks,6 months and 12 months after PD treatment were retrieved including hemoglobin(HB),blood potassium,blood calcium,blood phosphorus;calcium-phosphorus product(Ca×P),blood urea nitrogen(BUN),serum creatinine(SCr),uric acid(UA),alkaline phosphatase(ALP),serum albumin(ALB),blood glucose,total cholesterol,triglyceride,estimated glomerular filtration rate(eGFR),parathyroid hormone(iPTH),ferritin,glucose exposure,weekly total urea clearance rate(Kt/V)and total creatinine clearance rate(TCcr).The incidence of peritonitis:the number of peritonitis times divided by the total follow-up time(years),expressed in patient/year.Calculation of glucose exposure:the glucose content in peritoneal dialysate was calculated,expressed in g/24h.3.Statistical methodsStatistical analysis was performed using SPSS version 21.0.Data are presented as mean ± SD for normally distributed variables or median(25-75th percentiles)for non-normally distributed variables,which are analysed by repetitive measure analysis of variance or Greenhouse-Geisser method.χ2 test was used for comparisons among categorical data which are presented as number(%).Independent risk factors for peritonitis were assessed in univariate and multivariate Cox’s proportional hazard models.Kaplan-Meier survival analysis was used to compare the time-to-peritonitis of high and low glucose exposure groups and Log-rank test was performed.According to the median glucose exposure at 6 weeks,6 months and 12 months after the initial treatment of peritoneal dialysis,the patients were divided into the high glucose exposure group(>90 g/24 h)and the low glucose exposure group(≤ 90 g/24 h).P<0.05 were considered significant.Results1.According to the criteria,227 PD patients were recruited in the study.By the end of follow-up,56 patients(24.67%)had PDAP,with a total of 79 times.Patients were on dialysis for 13(8,21)months at the first episode of peritonitis and the incidence of peritonitis was 0.16 patients/year.2.The clinical data of patients at 6 weeks,6 months and 12 months were analyzed and the average glucose exposure was(83.3 g±21.2)g/24 h,(101.5 ±30.6)g/24 h and(112.0± 31.6)g/24 h respectively(P<0.001).Hb,blood phosphorus,Ca × P,iPTH,BUN,Scr,eGFR and ferritin were significantly different(all P<0.05),while SBP,blood calcium,UA,ALP,ALB,blood glucose,total cholesterol,triglyceride,total Kt/V and TCcr had no significant difference.3.Independent risk factors for peritonitis were assessed in univariate and multivariate Cox’s proportional hazard models.Univariate Cox regression analysis showed that glucose exposure at 6 weeks and blood glucose at 12 months were risk factors for PDAP[(HR=1.929,95%CI 1.033-3.600,P=0.039)and(HR=0.479,95%CI 0.351-1.993,P=0.025)].After adjusting for the covariates,including age,hemoglobin,blood glucose(categorical variable),total cholesterol and ferritin,multivariate Cox regression analysis showed that glucose exposure at 6 weeks was still an independent risk factor for PDAP(HR=2.165,95%CI 1.066-4.397,P=0.033),and age at 6 weeks and 12 months was also a risk factor for PDAP[(HR=1.374,95%CI 0.54-1.792,P=0.019)and(HR=1.691,95%CI 1.042-2.744,P=0.033)].4.χ2 test was used for comparisons of incidence rate of PDAP among different glucose exposure groups.The incidence rate of PDAP in high glucose group was higher than that in low glucose group at 6 weeks(χ2=6.480 P=0.011).However,there was no significant difference in the incidence rate between the two groups at 6 months and 12 months[(χ2=1.860,P=0.173)and(χ2=0.196,P=0.658)].5.Kaplan-Meier survival curve was used to analyze the time-to-peritonitis of patients with different glucose exposure.At 6 weeks and 6 months,patients with high glucose exposure had a shorter time to peritonitis than those with low glucose exposure[(log rank χ2=10.180,P=0.001)and(log rank χ2=3.992,P=0.046)],but there was no significant difference between the two groups at 12 months(log rank χ2=0.002,P=0.966).Conclusion1.Early glucose exposure was an independent risk factor for peritoneal dialysis associated peritonitis.2.In the early stage of peritoneal dialysis,compared with patients with low glucose exposure,patients with high glucose exposure had a high incidence and early onset of peritoneal dialysis associated peritonitis.