Associates of mortality among peritoneal dialysis patients with special reference to peritoneal transport rates and solute clearance.

The current report describes the distributions of selected demographic and biochemical parameters, clearance, and other transport values among patients undergoing peritoneal dialysis (PD) and evaluates the associates of mortality using those values, with and without clearance and peritoneal equilibration test (PET) data. All patients receiving PD on January 1, 1994 were selected (n = 2,686). Patients who switched to another form of dialysis during the study period were removed from the study at the time of therapy change. Working files were constructed from the clinical database to include demographic, laboratory, and outcome data. Laboratory data were available in only 1,603 patients and were used to evaluate the biochemical associates of mortality after merging the biochemical, demographic, and outcome data. Patients with clearance data or PET studies underwent a second analysis to assess the effects of peritoneal and renal clearance on survival. The analysis of demographic and laboratory data confirmed the importance of age and serum albumin concentration as predictors of death. Residual renal function (RRF) was strongly correlated with survival, but peritoneal clearance was not. Several possible explanations for the lack of correlation between peritoneal clearance and survival are discussed. The data suggest that RRF and peritoneal clearance may be separate and not equivalent quantities. Substantial work is required to confirm or refute these findings, because the information is essential to establish the adequate dose of PD in patients with various degrees of RRF.     

Quantifying comorbidity in peritoneal dialysis patients and its relationship to other predictors of survival.

BACKGROUND: Comorbidity is the single most important determinant of outcome in patients on renal replacement therapy. The aims of this study were to evaluate a semi-quantitative approach to comorbidity scoring in predicting survival of patients commencing peritoneal dialysis (PD), and to establish the interaction between this and other known predictors of patient outcome, in particular membrane function, residual renal function (RRF) and plasma albumin. METHODS: Comorbidity was recorded in a prospective, single centre cohort study of 303 patients commencing on PD. Using seven disease domains, chosen to reflect the dominance of cardiovascular morbidity in the end-stage renal failure population, comorbidity was graded as '0' when absent, '1' when one or two, and '2' when three or more conditions were present. The Wright comorbidity index, which includes age within the scoring method, was also evaluated. RRF, plasma albumin and peritoneal solute transport were measured every 6 months. Patients were censored at death. RESULTS: Median survival according to grade of comorbidity was 105, 42 and 29 months, respectively (P<0.0001), with good separation of the actuarial survival curves. Using Cox regression, the addition of age and the grade of comorbidity to Kt/V(urea), solute transport and plasma albumin increased the predictive power of the model. All were independent predictors of outcome with the exception of albumin. The Wright comorbidity index also enhanced the Cox model, although was not as powerful as when age and comorbidity were considered independently. At baseline, RRF was not different according to comorbidity unless diabetes was considered separately. Diabetics started with higher RRF, but after 6 months on PD this was the same as non-diabetic patients. Otherwise, initial rate of decline of RRF was similar across the comorbid grades, although the impact of higher drop-out due to earlier loss in patients with more comorbidity may have disguised earlier loss in these patients. Peritoneal solute transport tended to be higher in patients with increased comorbidity at baseline, chi(2) 13.8, P=0.032, and this was sustained with time on treatment. CONCLUSION: Comorbidity has a quantitative effect on survival that is independent of age, RRF and membrane function in PD patients. Comorbidity also appears to be associated with increased solute transport at the start of treatment, which is sustained. With the exception of diabetes, grade of comorbidity does not have a profound effect on loss of RRF.     

腹膜厚度与腹膜溶质转运功能的相关性

目的 探讨腹膜透析患者腹膜厚度与基线溶质转运功能的关系,分析腹膜转运功能的影响因素.方法 入选2017年1月至2019年6月福建省龙岩市第二医院肾内科收治的非糖尿病终末期肾脏病(ESRD)患者为研究对象.腹膜透析置管术前用彩色超声仪测量患者壁层腹膜厚度.腹膜透析治疗后1个月行标准腹膜平衡试验(PET)检查,以4h腹透液的矫正肌酐与2h血清肌酐的比值(D/Pcr)作为基线溶质转运指标,并按照D/Pcr评估结果分为高/高平均转运(H)组(D/Pcr≥0.65)和低/低平均转运(L)组(D/Pcr< 0.65).比较两组患者临床资料、壁层腹膜厚度和腹膜透析相关指标的差异;二元Logistic回归法分析腹膜转运功能的影响因素.结果 共纳入70例非糖尿病ESRD患者,H组患者腹膜超滤量显著低于L组;腹膜内生肌酐清除率(Ccr)和腹膜厚度显著高于L组(均P<0.05).Pearson及Spearman相关性分析结果显示,腹膜透析患者壁层腹膜厚度与溶质转运指标D/Pcr(r=0.673)、腹膜内生肌酐清除率(Ccr,r=0.261)呈正相关,与腹膜透析超滤量呈负相关(r=-0.365,均P<0.05).偏相关分析结果显示,腹膜厚度与溶质转运指标D/Pcr (r=0.539)、腹膜Ccr(r=0.338)呈正相关(均P<0.05).二元Logistic回归分析结果显示,腹膜增厚是腹膜转运功能的危险因素(OR=1.175,95%CI1.009~ 1.369,P=0.038).结论 非糖尿病腹膜透析患者壁层腹膜厚度与基线溶质转运指标呈正相关,腹膜增厚是影响腹膜转运功能的危险因素.     

Association between residual renal function, inflammation and patient survival in new peritoneal dialysis patients.

BACKGROUND: The recent ADEMEX study (Paniagua R, Amato D, Vonesh E et al. J Am Soc Nephrol 2002; 13: 1307-1320) indicates that peritoneal small solute clearance is not as critical for the survival of peritoneal dialysis (PD) patients as thought previously. On the other hand, low residual renal function (RRF), inflammation and an increased peritoneal transport rate (PTR) as evaluated by the peritoneal equilibration test (PET) are reported to be associated with increased mortality in PD patients, but the relationships between these factors and their separate and combined impact on the survival of PD patients are not clear. In this retrospective analysis, we evaluated possible relationships between RRF, inflammation and initial PTR in patients starting PD and the impact of these factors on patient survival. METHODS: A total of 117 patients with initial assessments for RRF, serum C-reactive protein (CRP) and PET at a mean period of 0.4+/-0.2 months (range 0.1-1.0 months) after start of PD were included in this study. Based on RRF (cut-off point, 4 ml/min/1.73 m(2)), serum CRP (cut-off point, 10 mg/l), and the dialysate to plasma creatinine ratio at 4-h of dwell (mean+1 SD), the patients were divided into different groups: low RRF and high RRF group, high CRP and normal CRP group and high PTR and other PTR group, respectively. RESULTS: Of 117 patients, 54 patients (46%) were in low RRF (<4 ml/min/1.73 m(2)) group, 36 patients (31%) were in high serum CRP (> or = 10 mg/l) group and 17 patients (15%) were in high PTR group. Forty-nine patients (42%) had one of these characteristics, 26 patients (22%) had two of these characteristics, two patients (2%) had three, and 40 patients (34%) had none of these characteristics. Patients with low RRF were older and had a higher prevalence of high CRP, lower normalized protein equivalent of total nitrogen appearance (nPNA), lower total Kt/V(urea) and lower total creatinine clearance (CCr) whereas patients with high CRP were older and had a higher proportion of men, lower serum albumin, lower nPNA, lower RRF and lower total CCr. Patients with high PTR had lower serum albumin, higher RRF and higher total CCr compared with patients with other PTR. Upon logistic multiple regression analysis, age and RRF were identified as factors affecting inflammation. Overall patient survival was significantly lower in the patients with low RRF, with high CRP, and in patients with more than two of the following: low RRF, high CRP and high PTR. In contrast, in patients with none of the discriminators low RRF, high CRP and high PTR, the 5-year survival was 100%. A high PTR was associated with decreased survival during the initial year on PD, but not thereafter. Patients who died during the follow-up period had a higher prevalence of high CRP and lower serum albumin, lower RRF, lower Kt/V(urea) and lower total CCr. Upon Cox proportional hazards multivariate analysis, age and RRF were predictors of mortality. CONCLUSIONS: These results indicate that in patients starting PD, low initial RRF is associated with inflammation, and low RRF and inflammation are both associated with high overall mortality. A high PTR was associated with higher mortality, but only during the initial year on PD, whereas Kt/V(urea) did not predict mortality. These results indicate the importance of RRF and inflammation as predictors of mortality in PD patients whereas the predictive power of PTR as such may lose its significance if these two parameters are taken into consideration.     

Cystatin C as marker of residual renal function in patients on peritoneal dialysis: relation with parameters of peritoneal function

INTRODUCTION: Cystatin C (CysC) is a nonglycosylated protein of low molecular weight not influenced by age, sex or inflammation. The aim of this paper is to ascertain the usefulness of serum CysC level determination in peritoneal dialysis (PD) patients. MATERIAL AND METHODS: CysC serum levels were determined in 80 PD patients. The mean age of patients was 53.7 +/- 15 years, with 15.3 +/- 25.8 months on PD. Thirty-three percent were on continuous ambulatory peritoneal dialysis (CAPD) and 66.3% on automated peritoneal dialysis (APD). Fourteen patients (17%) had no residual renal function (RRF). RESULTS: Mean CysC levels were 5.8 +/- 1.4 mg/L, without differences between men (5.5 +/- 1.4 mg/L) and women (5.6 +/- 1.5 mg/L, NS). There was no correlation between CysC levels and age, weight, height or time on PD. Anuric patients had CysC levels significantly higher than non-anuric (6.7 +/- 1.4 vs. 5.3 +/- 1.3 mg/L, p<0.001). CysC levels showed an inverse correlation with RRF (r=-0.60, p<0.001) and residual urine volume (r=-0.58, p<0.001). CONCLUSIONS: In conclusion, serum CysC levels had the same statistical significance as plasma creatinine levels, and they are not influenced by peritoneal transport in PD patients. Consequently, both parameters are valid RRF markers.     

Association between inflammation and changes in residual renal function and peritoneal transport rate during the first year of dialysis.

BACKGROUND: Peritoneal transport rate, a major determinant of peritoneal dialysis (PD) patient survival, increases in most patients starting on PD, while in other patients peritoneal transport rate may decline. Although several factors may contribute to changes in peritoneal transport rate, inflammation is known to be associated with a high peritoneal transport rate, and residual renal function (RRF), which often declines after start of PD, may also be related to inflammation. Therefore, we hypothesized that changes in peritoneal transport rate during patients' first year on PD and declining RRF may be linked with inflammation. METHODS: A total of 76 PD patients (40 males, mean age 56.8+/-14.1 years), who underwent two peritoneal equilibration tests at a mean of 0.4 months and 1 year after beginning PD, were included in the study. Based on the change in dialysate to plasma creatinine concentration ratio at 4-h dwell (D/P Cr) during first year on PD, the patients were divided into decreased or unchanged (group DUC; n=22) and increased (group I; n=54) groups. RESULTS: Initially, group I had a lower proportion of high transporters and more often high serum C-reactive protein (sCRP, > or =10 mg/l) and lower RRF compared with the DUC group. In group I, serum albumin and RRF decreased significantly and dialysate protein loss and glucose absorption increased significantly during the first year on PD. When patients were divided into two groups based on median change in RRF (1.9 ml/min), patients with a decrease in RRF >1.9 ml/min during first year on PD had a higher proportion of high sCRP, higher D/P Cr, and higher changes in D/P Cr compared to patients with a decrease in RRF < or =1.9 ml/min. Patients with elevated sCRP at one year included a higher proportion of patients who had high sCRP at the start of PD, higher increase in D/P Cr, lower serum albumin, lower RRF, and more decrease in RRF during first year on PD compared with patients having normal sCRP. RRF was inversely correlated with changes in D/P Cr during the first year on PD (r=-0.28, P=0.02). Multiple regression analysis revealed that the only factors affecting changes in D/P Cr were high sCRP and a low RRF. CONCLUSIONS: Our preliminary short-term study suggests that changes in peritoneal transport rate during patients' first year on PD may be linked with inflammation and declining residual renal function. Inflammation and residual renal function were identified as the only independent factors determining peritoneal transport rate during the first year on PD. It is possible that inflammation may cause both an increase in peritoneal transport rate and a decline in residual renal function, or that the decline in residual renal function and the increase in peritoneal transport rate may induce or aggravate inflammation. Further studies are needed to confirm these findings.     

Inherent high peritoneal transport and ultrafiltration deficiency: their mid-term clinical relevance.

BACKGROUND: High peritoneal transport has been associated with poorer outcome in peritoneal dialysis (PD) patients, but not necessarily because of PD-dependent conditions. Our primary objective was to analyse the influences of baseline peritoneal small solute transport and ultrafiltration (UF) capacity on patient and technique survival, after adjusting for comorbid conditions. A secondary objective was to determine whether high transport was associated with basal comorbidity. METHODS: In this prospective observational patient/technique survival study, we followed 410 patients who started PD. At the baseline, we collected data to define comorbidities, tally the Charlson index, determine the baseline mass transfer area coefficients (MTAC) of urea and creatinine, net UF, plasma albumin and residual renal function (RRF). No data other than the information on patient and technique survival were recorded after baseline. RESULTS: The mean follow-up was 33 +/- 28 months. Dropouts during the study were due to renal transplantation in 140 cases, death in 142 cases and transfer to haemodialysis (HD) in 77 cases. Patients with inherent UF deficiency, high transport rate or both were not significantly different in the survival analysis from the rest. In the Cox hazards analysis, only age, Charlson index and a lower RRF were the significant mortality risk factors. None of the baseline parameters studied was a predictor of technique failure. High transporter patients had lower plasma albumin and UF capacity, comorbidity and more frequent liver diseases than the rest. Moderate to severe liver disease (n = 14) was significantly associated with the inherent high transport status, but was never accompanied by UF failure (UFF). UFF patients showed higher RRF, creatinine-MTAC and age. CONCLUSIONS: Neither the high transport nor the inherent UFF status has any influence on patient and technique survival. The inherent high small solute transport status is associated with hypoalbuminaemia and a greater comorbidity index. The Charlson index, age and lower RRF are the only independent predictors of mortality. Technique dropout is not predicted by any of the variables studied at the baseline.     

Inflammation, residual kidney function, and cardiac hypertrophy are interrelated and combine adversely to enhance mortality and cardiovascular death risk of peritoneal dialysis patients

C-reactive protein (CRP), the prototype marker of inflammation, and cardiac hypertrophy are important prognostic indicators in dialysis patients. Residual renal function (RRF) has also been shown to influence survival of peritoneal dialysis (PD) patients. This study examined the relations between inflammation, RRF, and left ventricular hypertrophy (LVH) and determined whether inflammation, RRF, and LVH combine adversely to predict the outcomes of PD patients. A prospective observational study was performed in 231 chronic PD patients. Left ventricular mass index (LVMi), residual glomerular filtration rate (GFR), CRP, hemoglobin, serum albumin, and BP were determined at study baseline and related to outcomes. On univariate analysis, age (P = 0.002), dialysis duration (P = 0.004), coronary artery disease (P < 0.001), pulse pressure (P < 0.001), hemoglobin (P < 0.001), serum albumin (P = 0.032), log-CRP (P < 0.001), and GFR (P < 0.001) were significantly associated with log-LVMi. Log-CRP was positively correlated with pulse pressure (R = 0.218, P = 0.001) and negatively correlated with GFR (R = -0.272, P < 0.001). Multivariate analysis showed that log-CRP (P = 0.008) and RRF (P = 0.003) remained associated with log-LVMi independent of hemoglobin, serum albumin, arterial pulse pressure, and coronary artery disease. After follow-up for 30 +/- 14 mo, 34.2% patients had died. CRP, RRF, and LVMi each were significantly predictive of all-cause mortality and cardiovascular death. Kaplan-Meier analysis showed a significant increase in all-cause (P < 0.0001) and cardiovascular mortality (P < 0.0001) as the number of risk factors, namely CRP >/=50th percentile, no RRF, and LVMi>/= 50th percentile increased with the 2-yr all-cause mortality and cardiovascular death reaching as high as 61% and 46%, respectively, for patients who had all three risk factors. Compared with patients with none of the three risk factors, those with all three risk factors had an adjusted hazards ratio of 6.94 (P < 0.001) and 5.43 (P = 0.001) for all-cause mortality and cardiovascular mortality, respectively. In conclusion, inflammation, RRF, and LVH are interrelated and combine adversely to increase mortality and cardiovascular death risk of PD patients.     

血清白蛋白水平对腹膜透析患者残余肾功能的影响

目的 研究血清白蛋白水平对腹膜透析患者残余肾功能的影响.方法 54例腹膜透析患者以血清白蛋白35 g/L为界,血清白蛋白≥35 g/L为A组,血清白蛋白<35 g/L为B组,测定血清白蛋白、血肌酐、血尿素氮,白细胞介素6、肿瘤坏死因α,留取24 h尿量及腹透液、记录总量并检测尿素氮、肌酐;残余肾功能等.随访过程中观察以上指标和残余.肾功能(RRF).结果 B组中糖尿病肾病患者的比例高于A组,相关分析结果显示血清白蛋白水平与炎症介质白细胞介素6及肿瘤坏死因α水平呈负相关(r分别=-0.48、-0.64,P均<0.05),随着透析时间的延长两组患者RRF均下降,而B组RRF自腹膜透析6个月时即开始下降,与透析初月比较差异有统计学意义(P<0.05),12个月时A组RRF与透析初月时比较差异有统计学意义(P<0.05),A、B组RRF比较差异也有统计学意义(P<0.05).相关分析结果显示残余肾功能下降绝对值(△RRF)与血清白蛋白水平呈负相关(r=-0.31,P<0.05),与白细胞介素6及肿瘤坏死因α水平呈正相关(r分别=0.45、0.58,P均<0.01).结论 营养不良导致低水平的血清白蛋白是促进腹膜透析患者残余肾功能下降的因素之一,高水平的炎症介质也加速了残余肾功能的恶化.     

Reduced residual renal function is a risk of peritonitis in continuous ambulatory peritoneal dialysis patients.

BACKGROUND: Loss of residual renal function (RRF) contributes to anaemia, inflammation and malnutrition and is also a strong predictor of mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. However, the role of RRF on peritonitis is not yet clearly established. This study aimed to evaluate the effect of RRF on the development of peritonitis. METHODS: Study subjects were 204 end-stage renal disease (ESRD) patients who started PD from January 2000 to December 2005. Biochemical and clinical data within 1 month of PD commencement were considered as baseline. To determine risk factors for peritonitis, multivariate Cox regression was performed. Kaplan-Meier analysis and log-rank test were used to examine the difference of peritonitis-free period according to the presence of diabetes and RRF. RESULTS: On univariate analysis based on baseline data in first peritonitis, diabetes was less prevalent and RRF (6.7+/-2.6 vs 4.0+/-2.3 ml/min/1.73 m2, P<0.01), haemoglobin (10.9+/-1.2 vs 10.6+/-1.2 g/dl, P<0.05) and serum albumin level (3.6+/-0.4 vs 3.4+/-0.4 g/dl, P<0.01) were significantly higher in the peritonitis-free group. Kaplan-Meier analysis showed that time to first PD peritonitis episode was significantly longer in the non-diabetic patients (P<0.001) and in patients with higher residual GFR (P<0.001). Multivariate analysis showed that diabetes [hazard ratio(HR) 1.64, P<0.05] and RRF (per 1 ml/min/1.73 m2 increase, HR 0.81, P<0.01) were independent risk factors. CONCLUSION: Our study revealed that RRF and diabetes were risk factors for peritonitis. These results suggest that preservation of RRF should be viewed as a protective strategy to reduce peritonitis.     

Important differentiation of factors that predict outcome in peritoneal dialysis patients with different degrees of residual renal function.

BACKGROUND: Residual renal function (RRF) is an important predictor of outcome in peritoneal dialysis (PD) patients. Whether results from survival studies in dialysis patients with RRF can also be extrapolated to anuric patients remains uncertain. In this observational study, we examined the characteristics of PD patients with a residual glomerular filtration rate (GFR) > or =1 ml/min per 1.73 m2 vs those with complete anuria and differentiated factors that predict outcome in the two groups of patients. METHODS: Two hundred and forty-six continuous ambulatory peritoneal dialysis (CAPD) patients (39% being completely anuric) were recruited from a single regional dialysis centre. Assessments of haemodynamic, echocardiographic, nutritional and biochemical parameters and indices of dialysis adequacy were done at study baseline and were related to outcomes. RESULTS: During the prospective follow-up of 30.8+/-13.8 (mean+/-SD) months, 28.0% of patients with residual GFR > or =1 ml/min per 1.73 m2 vs 50.5% of anuric patients had died (P = 0.005). The overall 2 year patient survival was 89.7 and 65.0% for patients with GFR > or =1 ml/min per 1.73 m2 and anuric patients, respectively (P = 0.0012). Compared with patients with GFR > or =1 ml/min per 1.73 m2, anuric patients were dialysed for longer (P<0.001), were more anaemic (P<0.005), and had higher calcium-phosphorus product (P<0.01), higher C-reactive protein (P<0.001), lower serum albumin (P<0.05), greater prevalence of malnutrition according to subjective global assessment (P<0.05) and more severe cardiac hypertrophy (P<0.001) at baseline. Using multivariable Cox regression analysis, serum albumin, left ventricular mass index and residual GFR were significant factors associated with mortality in patients with GFR > or =1 ml/min per 1.73 m2, while increasing age, atherosclerotic vascular disease and higher C-reactive protein were associated with greater mortality in anuric PD patients. CONCLUSIONS: Our study demonstrates more adverse cardiovascular, inflammatory, nutritional and metabolic profiles as well as higher mortality in anuric PD patients. Furthermore, factors associated with mortality are also not equivalent for PD patients with and without RRF, suggesting that patients with and without RRF are qualitatively different.     

Impacts of baseline peritoneal transport characteristics and their changes during follow up on the survival of peritoneal dialysis patients

Objective To evaluate the effects of baseline and changes of peritoneal transport characteristics on the prognosis of maintaining peritoneal dialysis (PD) patients. Methods Five hundred and eight-six PD patients who started PD from September 11, 2006 to October 30, 2014 in a single center were included and followed up until March 30, 2016. According to their baseline D/Pcr value in peritoneal equilibrium test (PET), the patients were divided into high transport (H) group (D/Pcr 0.82-1.03), high average transport (HA) group (D/Pcr 0.65-0.81), low average transport (LA) group (D/Pcr 0.50-0.64) and low transport (L) group (D/Pcr 0.34-0.49). According to the changes of follow-up D/Pcr comparing with baseline D/Pcr, the patients were also divided into ascending group, descending group and no-change group. The patient and technical survival rates were estimated by Kaplan-Meier analysis. Cox proportional hazards analyses were used to analyze the risk factors for PD patient death and technical failure. Results There were 67 patients in L group, 229 patients in LA group, 252 patients in HA group, and 38 patients in H group. The patient survival rate in H group was significantly lower than those of L group (P=0.036), LA group (P=0.008) and HA group (P=0.041). There was no significant difference on technical survival rate among these 4 groups. According to the tendency of follow-up D/Pcr changes, there were 127 patients in ascending group, 101 patients in descending group and 179 patients in no-change group. There was no significant difference on patient survival among these 3 groups (P=0.064). However in patients with a high transport rate (D/Pcr≥0.65), the patient survival was lower in descending group than those in ascending group (P=0.033) and no-change group (P=0.049). Age over 65 years old (HR=2.499), malnutrition during follow-up (HR=3.144), ultrafiltration less than 400 ml/d during follow-up (HR=1.863) and high sensitive C reactive protein≥10 mg/L (HR=4.526) were the independent risk factors for patient death (all P＜0.05). Gender (HR= 1.609), age over 65 years old (HR=1.929), ultrafiltration less than 400 ml/d during follow-up (HR=1.708), high sensitive C reactive protein≥10 mg/L (HR=1.829), malnutrition (HR=1.876) and change of peritoneal transport function (HR=0.579) affect technical failure (all P＜0.05). Conclusions The survival rate of PD patients with basal high peritoneal transit is relatively low, especially for patients with descending transport rate during follow-up. The concern on the peritoneal transport status is constructive for the prognosis of PD patients.     

Possible factors contributing to similar peritoneal dialysis outcome in patients over 60 years of age and the younger ones

The aim of studies was a comparison of dialysisadequacy, nutritional parameters, results ofthe peritoneal equilibration test (PET) andselected standard clinical and laboratory datain peritoneal dialysis (PD) patients withdifferent age, but comparable PD duration andoutcome. Two groups of patients were examined:group I (n = 21, 9 F, 12 M) – age 67.7 ±4.5 yrs, PD duration 20.1 ± 12.1 months;group II (n = 21, 9 F, 12 M) – age 42.8 ±9.1 yrs, PD duration 20.7 ± 12.1 months.Parameters of PD adequacy, results of PET,markers of nutrition and standard laboratorymeasures were determined every 3 months to theend of PD treatment. First obtained values,mean values representing the entire PD courseand last values obtained before the end of PDtherapy were compared in group I and II.Differences in results obtained at thebeginning and at the end of PD therapy werealso compared in each group. At the beginningof PD therapy the older patients showed highertotal fat mass (TFM) expressed as % of totalbody mass (TBM), lower lean body mass (LBM),lower serum levels of iron, phosphorus andcreatinine as well as lower transferrinsaturation. When mean values representing theentire PD course were compared, the olderpatients showed higher TFM as % of TBM andserum ferritin level, whereas lower values wereobserved for diastolic blood pressure (DBP),LBM, serum creatinine, phosphorus and iron. Atthe end of PD therapy TFM as % of TBM and serumferritin level remained higher in olderpatients as well as lower both DBP and LBM weremaintained. Additionally, serum cholesterollevel and residual renal function (RRF) becameat the end of PD treatment higher in the olderindividuals compared to the younger ones. Thedifference in RRF between the two groups wascaused by the decline in RRF in the youngerpatients with relatively stable values of RRFin the older ones. Nutritional parametersimproved in the course of PD only in theyounger group. In conclusion, the olderpatients reach similar PD outcome parameterscompared to the younger ones while they showhigher TFM as % of TBM, stable RRF and moresatisfactory DBP. However, elderly patientsshow a greater progress in the deterioration ofindices of both inflammation andatherosclerosis and therefore are not able toimprove nutritional parameters.     

Benefits of preserving residual renal function in peritoneal dialysis

Residual renal function (RRF) is of paramount importance in patients with end-stage renal disease, with benefits that go beyond contributing to achievement of adequacy targets. Several studies have found that RRF rather than overall adequacy (as estimated from total small solute removal rates) is an essential marker of patient and, to a lesser extent, technique survival during chronic peritoneal dialysis (PD) therapy. In addition, RRF is associated with a reduction in blood pressure and left ventricular hypertrophy, increased sodium removal and improved fluid status, lower serum beta(2)-microglobulin, phosphate and uric acid levels, higher serum hemoglobin and bicarbonate levels, better nutritional status, a more favorable lipid profile, decreased circulating inflammatory markers, and lower risk for peritonitis in PD. As compared with conventional hemodialysis, PD is associated with a slower decrease in RRF. This highlights the usefulness of strategies oriented to preserve both RRF and the long-term viability of the peritoneal membrane. Several factors contributing to the loss of RRF have been identified and should be avoided. Renoprotective drugs and new glucose-sparing, more biocompatible PD regimes may prove useful tools to preserve RRF and peritoneal membrane function in the near future.     

Effect of fluid and sodium removal on mortality in peritoneal dialysis patients

Effect of fluid and sodium removal on mortality in peritoneal dialysis patients. BACKGROUND: Adequacy of peritoneal dialysis (PD) traditionally is assessed using Kt/V(urea) and total creatinine clearance (TCC). However, this approach underestimates the importance of fluid and sodium removal. The aim of this study was to determine the effect of fluid and sodium removal on morbidity and mortality in PD patients. METHODS: One hundred twenty-five PD patients were monitored for three years from the beginning of the treatment. The effects of demographic features, comorbidity, peritonitis rate, blood pressure, medications, blood biochemistry, peritoneal membrane transport characteristics, residual renal function (RRF), Kt/V(urea), TCC, normalized protein nitrogen appearance (nPNA), and removal of sodium and fluid on mortality were evaluated. Total and cardiovascular hospitalization rates were also recorded. A Cox proportional hazards model was used to determine factors predicting mortality. RESULTS: In the Cox model, comorbidity, total sodium and fluid removals, hypertensive status, serum creatinine, and RRF were independent factors affecting survival. In contrast, Kt/V(urea) or TCC did not affect the adjusted survivals. Total sodium and fluid removal and hypertensive status also significantly influenced the hospitalization rate. Systolic and diastolic blood pressures were negatively correlated with total fluid (P < 0.001) and sodium removal (P < 0.001). CONCLUSIONS: Together, these findings suggest that removal of sodium and fluid is a predictor of mortality in PD patients, whereas Kt/V(urea) and TCC are not factors. Adequate fluid and sodium balance is crucial for the management of patients on PD.     

Randomized controlled study of biocompatible peritoneal dialysis solutions: effect on residual renal function

Residual kidney function is important for patient and technique survival in peritoneal dialysis (PD). Biocompatible dialysis solutions are thought to improve function and viability of peritoneal mesothelial cells and to preserve residual renal function (RRF). We conducted a randomized controlled study comparing use of biocompatible (B) with standard (S) solutions in 93 incident PD patients during a 1-year period. The demographics, comorbidities, and RRF of both groups were similar. At 3 and 12 months, 24-h urine samples were collected to measure volume and the mean of urea and creatinine clearance normalized to body surface area. Surrogate markers of fluid status, diuretic usage, C-reactive protein concentration, peritonitis episodes, survival data, and peritoneal equilibrium tests were also collected. Changes in the normalized mean urea and creatinine clearance were the same for both groups, with no significant differences in secondary end points. Despite non-randomized studies suggesting benefits of these newer biocompatible solutions, we could not detect any clinically significant advantages. Additional studies are needed to determine if advantages are seen with longer term use.     

不同腹膜转运功能的腹膜透析患者的营养不良-微炎症状态评估

目的 评价不同腹膜转运特性的持续性非卧床腹膜透析(CAPD)患者的营养不良-微炎症状态.方法 选择本院稳定腹膜透析半年以上的患者170例,按照腹膜平衡试验计算结果,将患者分为高转运组、高平均转运组、低平均转运组和低转运组.对各组患者的营养及炎症指标进行检测,检测指标包括人体测量指标和生化指标,并根据营养不良-炎症评分表,对每组患者进行评分.对四组患者的各项指标进行方差分析,对各组间指标的均数进行两两比较,并将腹膜平衡试验的D/Pcr与营养不良-微炎症指标进行相关性分析,综合评估各组患者的营养不良-微炎症状态严重程度.结果 符合纳入标准的患者中高转运组24例、平均转运组42例、低平均转运组50例、低转运组54例.MIS分值越高,患者的营养状况越差,微炎症状态越严重,D/Pcr与PD患者人体测量指标、贫血指标和营养指标呈负相关,与炎症指标呈正相关.四组患者的相关指标均有显著性差异,按营养不良-微炎症状态的严重程度排列为:高转运＞高平均转运＞低平均转运＞低转运.结论 不同腹膜转运特性对腹膜透析患者的营养不良-微炎症状态有不同的影响,高通透性腹膜功能患者营养不良-微炎症状态较低通透性者差,故应加强对高通透性CAPD患者的腹透方案调整及营养管理.     

Hyperleptinaemia and chronic inflammation after peritonitis predicts poor nutritional status and mortality in patients on peritoneal dialysis.

BACKGROUND: The serum leptin level is elevated in patients undergoing peritoneal dialysis (PD) and associated with a loss of lean body mass. The nutritional status of PD patients may further be worsened following peritonitis. We investigated the association between hyperleptinaemia, inflammation and malnourishment in PD-related peritonitis. METHODS: We conducted a prospective study on PD patients who developed peritonitis. Blood samples were obtained as baseline (D0) before the onset of peritonitis, and once peritonitis developed, leptin, adiponectin (ADPN) and other inflammatory markers were collected, on day 1 (D1), day 7 (D7) and day 42 (D42) of peritonitis. Patients were followed-up for any censor event or 1 year after peritonitis. RESULTS: Forty-two patients with a mean age of 62.9+/-13.2 years were recruited. Fourteen (33.3%) were diabetic. The serum leptin levels increased significantly from baseline to day 1 and 7, but fell back to the premorbid state at day 42. In contrast, the ADPN level decreased from a baseline value of 15.60+/-10.4 microg/ml to 13.01+/-8.1 microg/ml on day 1 (P=0.01) but rose to 14.39+/-8.9 microg/ml on day 7 (P=0.28) and 13.87+/-7.9 microg/ml on day 42 (P=0.21). High-sensitivity C-reactive protein (hs-CRP) increased significantly from baseline to day 1, 7 and even at day 42. The lean body mass (LBM) and nutritional markers decreased significantly after peritonitis. For patients with high hs-CRP (>3.0 mg/l) at day 42, there was a higher mortality rate than for those with lower hs-CRP (<3.0 mg/l, P=0.02), even if they were in clinical remission of peritonitis. CONCLUSIONS: Our study confirmed an increase in serum leptin during acute peritonitis and a prolonged course of systemic inflammation after apparent clinical remission of peritonitis. These factors related to the persistent chronic inflammation may contribute to the development of malnourishment and poor survival rate.