Lower Residual Renal Function Research Articles

Hypoglycemia and Mortality Risk in Incident Hemodialysis Patients

BackgroundHypoglycemia is a frequent occurrence in chronic kidney disease (CKD) patients due to alterations in glucose and insulin metabolism. However, there are sparse data examining the predictors and clinical implications of hypoglycemia including mortality risk among incident hemodialysis patients. MethodsAmong 58,304 incident hemodialysis patients receiving care from a large national dialysis organization over 2007-2011, we examined clinical characteristics associated with risk of hypoglycemia, defined as a blood glucose concentration <70 mg/dL, in the first year of dialysis using expanded case-mix+laboratory logistic regression models. We then examined the association between hypoglycemia during the first year of dialysis with all-cause mortality using expanded case-mix+laboratory Cox models. ResultsIn the first year of dialysis, hypoglycemia was observed among 16.8% of diabetic and 6.9% of non-diabetic incident hemodialysis patients. In adjusted logistic regression models, clinical characteristics associated with hypoglycemia included younger age, female sex, African-American race, presence of a central venous catheter, lower residual renal function, and longer dialysis session length. In the overall cohort, patients who experienced hypoglycemia had a higher risk of all-cause mortality risk (reference: absence of hypoglycemia): adjusted HR (95%CI) 1.08 (1.04, 1.13). In stratified analyses, hypoglycemia was also associated with higher mortality risk in the diabetic and non-diabetic subgroups: adjusted HRs (95% CI’s) 1.08 (1.04-1.13), and 1.17 (0.94-1.45), respectively. ConclusionsHypoglycemia was a frequent occurrence among both diabetic and non-diabetic hemodialysis patients, and was associated with higher mortality risk. Further studies are needed to identify approaches that reduce hypoglycemia risk in the hemodialysis population.

#4445 ANAEMIA MANAGEMENT IN PERITONEAL DIALYSIS: FROM GUIDELINES TO ROUTINE CLINICAL PRACTICE

Abstract Background and Aims The evidence on the management of renal anemia in peritoneal dialysis (PD) is much weaker than in hemodialysis (HD). Current guidelines establish the same haemoglobin (Hb) target for patients under eritropoietin stimulating agents (ESAs) in both dialysis techniques (PD, HD), although patients in PD are usually younger, more active and lesss comorbid. Unfortunately, there is not randomized controlled trials evaluating the efficacy and safety the effect of different Hb target on clinical outcomes. The aim is to describe the current situation of anaemia prevalence, treatments, and achievement of clinical guidelines recommendations in this population. Method Retrospective nationwide multicenter study including patients from 19 PD units. All prevalent PD patients that were active in the technique in November 2019 for at least 3 months was included (to avoid COVID pandemic interferences). Exclusion criteria were a previous kidney transplant failure and being on PD due to a cardiorenal syndrome with a residual renal function over 20 ml/min/1.73 m2. The nephrologists collected baseline data, demographics, comorbidities, and data related to anemia management (ie, laboratory values, previously prescribed treatments, and subsequent adjustments) from electronic medical records. The European adaptation of KDIGO guidelines was the reference for iron and Hb limits, prescriptions and targets. Results A total of 343 patients (mean age 62.9 years, 61.2% male) were included. Regarding anaemia-treatment prescription, 72.9% were receiving ESAs and 33.2% iron therapy (20.7% intravenously-IV and 12.5% orally). Eighty-two (32.8%) patients were receiving ESA without iron therapy, despite to have an indication to do it according ERBP guidelines in 53 out of them. After knowing lab results, iron therapy was only started in 8 (15%) patients. Among ESA-treated patients, 58.8% had an optimal control (Hb 10–12 g/dl). Seventeen patients had haemoglobin over 13 g/dl, and 12 of them continued receiving ESA after knowing lab results. Only three patients had persistent haemoglobin &amp;lt;10 g/dl. Seven patients (2%) met criteria for ESA resistance (epoetin dose &amp;gt;300 IU/kg/week). Patients in the highest tertile of erythropoietin resistance index (ERI) (&amp;gt;6.3 UI/kg/week/g/dl) were more inflamed, had lower albumin levels and lower residual renal function. Conclusion Anaemia prevalence is high in this population and its management in PD Units could be improved according to the ERBP guidelines. The lack of iron therapy in patients who should have received it and the excessive tolerance to high Hb levels are the most relevant opportunities to improve compliance with clinical guidelines.

#4202 FLUID OVERLOAD AT THE BEGINNING OF PERITONEAL DIALYSIS: A CROSS-SECTIONAL STUDY TO DETERMINE ITS ASSOCIATION WITH SERUM BIOMARKERS

Abstract Background and Aims Volume management in peritoneal dialysis (PD) patients is of major importance as fluid overload has been associated with cardiovascular and non-cardiovascular morbidity and mortality. Clinical examination itself has a poor diagnostic accuracy for minor deviations from normohydration, highlighting the need of additional tools. The aim of this study was to evaluate the association between serum biomarkers (CA-125 and NT-proBNP) and volume status, evaluated by clinical and bioimpedance analysis, at the initiation of PD technique. Method Single-center cross-sectional study including PD patients that started technique between 2017 and 2022. Demographic and clinical data were collected from the electronic records. Parameters evaluated were clinical examination, serum biomarkers, bioimpedance and dialysis adequacy. Results A total of 79 patients (51 male) were included with a mean age of 57±15 years. All of them started with CAPD and 52% were under icodextrin. Hypertension, cardiovascular disease and diabetes were present in 94%, 51% and 34%, respectively. The great majority were under renin-angiotensin-aldosterone system inhibitors (91%), beta-blockers (48%) and diuretic therapy (94%). Baseline PET showed that 77% were high or high-average transporters. Mean weekly Kt/V was 2.4±15. The mean residual renal function (RRF) and residual diuresis were 6.7±15 mL/min/1.73 m2 and 1.6±0.8 L (4% anuric), respectively, and 11% had ultrafiltration failure. Median nPCR was 0.9 g/Kg/day (IQR 0.3). Median NT-proBNP and CA-125 were 1337 pg/mL (IQR 3401) and 14.6 U/mL (IQR 17.6), respectively. NT-proBNP was positively associated with overhydration (OH &amp;gt;2 L) (r = 0.31; p = 0.009), CA-125 (r = 0.28; p = 0.01) and icodextrin use (p = 0.002). It was negatively associated with weekly Kt/V (r = -0.35; p = 0.003), RRF (r = -0.36; p = 0.002), ultrafiltration test (UFT) (r = -0.35; p = 0.003) and nPCR (r = -0.28; p = 0.001). CA-125 was positively associated with higher overhydration (OH &amp;gt; 3.6 L), D/P creatinine (r = 0.3; p = 0.004) and icodextrin use (p = 0.001). It was negatively associated with weekly Kt/V (r = -0.3; p = 0.01), UFT (r = -0.25; p = 0.03) and nPCR (r = -0.23; p = 0.04). NT-proBNP was still associated with overhydration in a multivariable analysis, adjusted to diabetes, icodextrin use, RRF and CA-125 (p = 0.024). Conclusion Serum NT-proBNP and CA-125 seem to be good markers of overhydration at PD baseline. They were also associated with worse dialytic efficacy and ultrafiltration, lower residual renal function and an early need of icodextrin use. Malnourished patients were associated with higher NT-proBNP and CA-125. Early and effective management of hydration may improve clinical outcomes, allowing personalized dialysis prescription and nutritional support.

#6140 DEPENDENCE IN THE ELDERLY PATIENT ON HEMODIALYSIS

Abstract Background and Aims Frailty constitutes a syndrome, characterized by loss of lean body mass (sarcopenia), weakness, and decreased resistance to physical exercise, which leads to decreased activity and a poor response to stress. Reduced activity, in turn, worsens sarcopenia and weakness, leading to a vicious cycle toward functional decline and increased risk of death. Frail patients starting HD may lose independence, as their functional capacity deteriorates, with increased frailty and sarcopenia, especially in the elderly. Aims: Observe the clinical differences in elderly patients on hemodialysis depending on whether they are dependent or not and observe if dependence has an impact on the dialysis regimen used. Method Observational descriptive study for 1 year in patients of the chronic hemodialysis program of four out-of-hospital centers and a hospital unit of the Fundación Renal Íñigo Álvarez de Toledo (Spain). Of the total number of patients receiving dialysis in the units, 107 over 75 years of age, who had been in the program for more than 3 months and who had signed the informed consent, were included in the study. The variables considered for the study were: age, sex, height, weight, and body mass index (BMI), etiology of kidney disease, time on hemodialysis, residual diuresis &amp;gt; 500 mL/min, and type of vascular access. In relation to the hemodialysis regimen, the duration variables were collected in hours of the HD session at the beginning of the program and at the time of the study, weekly hours and days per week Analytically determined: albumin, total iron binding capacity (TIBC) and creatinine. In addition, the measure of dialysis efficacy was established by eKt/V To assess the degree of functional dependency, the Barthel index is considered the most appropriate scale to assess the basic activities of daily living (BADL), obtaining a quantitative estimate of the degree of dependency. Results Association between dependency and the rest of the qualitative variables. Data expressed n (%) or mean ± SD. Conclusion Dependent patients have lower residual renal function, greater comorbidity, less ability to walk, and therefore need transportation to go to dialysis, live in residences, and are extremely tired at the end of dialysis.

Impact of different automated peritoneal dialysis modalities on the inflammatory profile of elderly patients with chronic kidney disease.

Chronic kidney disease, more prevalent in the elderly, is considered a public health issue worldwide. To evaluate the impact of automated, peritoneal dialysis modalities, intermittent and continuous, on the inflammatory profile of elderly people with chronic kidney disease. Prospective, cross-sectional and analytical study carried out in a dialysis clinic in Brasília - Brazil, with 74 elderly people aged 60 years or older. The patients underwent rapid Peritoneal Equilibration Test, clinical assessment, blood collection for biochemical and cytokine assessments, interleukin 6 and transforming growth factor beta 1, and answered a quality-of-life questionnaire (KDQOL-SF36). We used a 5% significance level for data analysis, associations and correlations. Patients in the continuous modality had higher serum values of transforming growth factor beta 1 than those in the intermittent modality, which had higher peritoneal transforming growth factor beta 1, age and residual renal function than those in continuous mode. Interleukin 6 dosage in the peritoneum was associated with age, while serum IL-6 was associated with IL-6 in the peritoneum, time on dialysis and age. There was no association between the modality and the presence of diabetes, blood volume or nutritional status. Both modalities enable good adaptation to the dialysis treatment. Inflammation in automated peritoneal dialysis is mainly associated with low residual renal function, advanced age and longer time on therapy, and not to the type of dialysis performed.

The Association Between Handgrip Strength and Predialysis Serum Sodium Level in Patients With Chronic Kidney Disease Stage 5D.

Purpose: Handgrip strength (HGS) is a useful tool for the systematic assessment of muscle function related to nutritional status. Reduced HGS has been associated with adverse clinical outcomes in chronic kidney disease (CKD) stage 5D patients. In the same patients, predialysis low serum sodium (sNa) has been associated with malnutrition and mortality. Here, we investigated the role of predialysis sNa on muscle function in CKD-5D patients.Methods: We evaluated 45 patients on hemodialysis (HD) and 28 patients on peritoneal dialysis (PD) with HGS measurement, bioimpedance analysis, anthropometric measures, and malnutrition inflammation score (MIS). According to established diagnostic criteria, reduced HGS was defined as strength below 30 and 20 Kg in men and women, respectively. Predialysis sNa values were defined as the mean of all predialysis measurements during the preceding 6 months. Data analysis was performed separately for each of the HD and PD groups.Results: The proportions of reduced HGS did not differ between the HD (66%) and PD (54%) groups, respectively. Patients in the HD group as compared to those in the PD group had higher serum albumin and potassium and mid-arm muscle circumference and lower residual renal function (RRF) and residual urine volume. Multivariate logistic analysis, after controlling for muscle mass, nutritional biomarkers, MIS, fluid overload and RRF, showed that for every 1 mmol/l increase of sNa the odds of reduced HGS was decreased by 60% (OR = 0.40, 95% CI: 0.16–0.99) and 42% (OR = 0.58, 95% CI: 0.36–0.93) in HD and PD patients, respectively. However, stratified analysis indicated that lower sNa levels predicted reduced HGS in individuals with a background of malnutrition, inflammation, overhydration and less preserved RRF, representing unfavorable conditions strongly related to muscle wasting in the dialysis setting.Conclusions: Predialysis sNa is a strong and independent determinant of HGS, a reliable nutritional marker in CKD-5D stage patients. However, according to our findings, lower sNa levels appear to be a marker of underlying unfavorable conditions that are heavily associated with reduced HGS, rather than a causal determinant of reduced HGS. Whether optimizing sNa levels improves patient muscle performance requires further investigations.

Hypomagnesemia as a Predictor of Cardiovascular Morbidity in Patients Undergoing Hemodialysis

Background: Dialysis patients may be particularly vulnerable to the effects of magnesium deficiency, yet scant if any attention is being given to this cation in most dialysis centers, which should be rectified. Objective: To find whether hypomagnesaemia represent an independent risk factor for increased cardiovascular morbidity in hemodialysis patient (HD) either with or without residual renal function (RRF). Patients and methods: 60 prevalent hemodialysis patients were included and subdivided into 15 each; group 1a with normal serum magnesium and residual renal function, group 1b with low serum magnesium and residual renal function, group 2a with normal serum magnesium and no residual renal function and group 2b with low serum magnesium and no residual renal function. Patients were subjected to history taking, clinical examination, lab. tests, echo and ECG. Results: Among 60 hemodialysis patients divided into 30 with RRF and 30 without, hypomagnesemia was found in 30% of whole patients. HD patients with RRF had lower mean serum magnesium level than those without. There was no statistical significant difference between the 2 groups regarding cardiovascular morbidities including diastolic dysfunction, pulmonary hypertension, and others, suggesting that RRF has no effect on cardiovascular morbidities in HD patients. There was no correlation between hypomagnesemia and diastolic dysfunction or pulmonary hypertension or hypertensive heart and left ventricular hypertrophy (LVH) or arrhythmias but we found significant correlation between hypomagnesemia and ischemic heart disease. Conclusion: There is a close relationship between hypomagnesemia and risk factors for cardiovascular disease morbidity in hemodialysis patients.`

Factors affecting the relationship between ionized and corrected calcium levels in peritoneal dialysis patients: a retrospective cross-sectional study

BackgroundChronic kidney disease-mineral and bone disorder (CKD-MBD) management in patients with end-stage renal disease is important owing to the risk of cardiovascular diseases. In clinical practice, we manage patients not by monitoring the levels of biologically active ionized calcium (iCa) but by monitoring total serum calcium or corrected calcium (cCa). We previously reported that iCa/cCa ratio was different between patients with hemodialysis and those with peritoneal dialysis (PD). In PD patients, several factors are expected to affect iCa/cCa ratio. Therefore, modifying the strategy to achieve better CKD-MBD management might be necessary; however, no reports have studied this to date. Therefore, we investigated the factors influencing iCa/cCa ratio in PD patients.MethodsThis retrospective cross-sectional study examined background and laboratory data, including iCa, collected at routine outpatient visits. The patients were divided into the first, second, and third tertile of iCa/cCa ratio groups to compare patient background and laboratory data. Multiple regression analysis was used to investigate the factors influencing iCa/cCa ratio. We used multiple imputation to deal with missing covariate data.ResultsIn total, 169 PD patients were enrolled. In PD patients with lower iCa/cCa ratio, PD duration was longer and pH was higher. Urine volume and weekly renal Kt/V were lower in the patients with lower iCa/cCa ratio than in those with higher iCa/cCa ratio. iCa/cCa ratio and weekly renal Kt/V were directly correlated (r = 0.41, p < 0.01), and weekly renal Kt/V and pH were independent factors affecting iCa/cCa ratio (t = 2.86, p < 0.01 and t = − 5.42, p < 0.01, respectively).ConclusionsiCa levels were lower in PD patients with lower residual renal function (RRF) even though their cCa levels were equal to those with maintained RRF, warranting caution in the assessment and management of CKD-MBD in PD patients.

P1258CLINICAL COMPARATIVE STUDY OF AORTIC ARCH CALCIFICATION IN PATIENTS WITH MAINTENANCE PERITONEAL DIALYSIS AND HEMODIALYSIS

Abstract Background and Aims Vascular calcification is known to be an important risk factor in patients with dialysis, However, the comparative study on vascular calcification between peritoneal dialysis (PD) and hemodialysis (HD) is less. The aim of this study was to analyze the presence, risk factors of aortic arch calcification (AAC), and compare the prognosis in maintenance PD and HD patients. Method Using retrospective analysis method, 177 patients with PD and 147 patients with HD were included in the study. The extent of AAC was evaluated by chest X-ray examination. The demographic characteristics and clinical data were collected and compared between PD group and HD group. Binary logistic regression analysis was performed to evaluate risk factors associated with the aortic arch calcification. Results The incidence of AAC in HD group (59.86%) was significantly higher than that in PD group (37.29%). Multivariate analysis showed that age, residual renal function (RRF) and serum phosphate were the independent risk factors for calcification of PD patients and the odds ratio (OR) values were 1.133, 1.039, 0.762 and 18.186, respectively. Similarly, age, RRF, calcium-phosphorus product and LDL were the risk factors of HD patients and their respective OR values were 1.125, 0.509, 2.755 and 3.221. Compared with patients without AAC, the presence of moderate-severe AAC was associated with greater risk of mortality, and the OR values were 17.833 and 20.056 in PD group and HD group, respectively. Conclusion Our findings suggest that the AAC was more common in HD patients. Older age and lower RRF are common independent risk factors for AAC in PD and HD patients. Moderate to severe AAC a ppears to be associated with increased risk of mortality.

P1215INVERSE ASSOCIATION BETWEEN DIALYSATE OXALATE REMOVAL AND INTRAPERITONEAL INFLAMMATION IN PERITONEAL DIALYSIS PATIENTS

Abstract Background and Aims Due to inadequate oxalate removal, hyperoxalemia is a well-established feature in end-stage renal disease (ESRD) patients. Considering the fact that oxalate is primarily removed by kidneys in healthy individuals, we hypothesized that oxalate elimination in peritoneal dialysis (PD) patients could be compensated by PD effluent (PDE). In addition, its dialysate concentration could be associated with intraperitoneal inflammation. In the present study, we investigated oxalate excretion in PDE and its association with intraperitoneal inflammation in PD patients. Method We performed a cross-sectional single-center observational study involving 30 PD patients (17 women and 13 men). The average age was 48.3 ± 9.2 years. Among them, there were 11 (37%) diabetics and 19 (63%) non-diabetic patients. The mean time on PD was 32 [18.5-47] months. Parameters of dialysis adequacy, cytokines concentration and oxalate removal levels with PDE were determined. The spectrophotometric method was performed for determining oxalate concentration in PDE using oxalate oxidase/peroxidase reagent (BioSystems, Spain). The ELISA method was used for the determination of interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) measurements in dialysate. For the statistical analysis, we used Kruskal-Wallis’s t-test and Spearman's rank correlation test. The median (Me) and interquartile ranges [Q25 - Q75] were calculated according to abnormal distribution. All statistical analyses were performed using MedCalc. Results No differences in peritoneal oxalate, IL-6, and MCP-1 excretion between diabetics and non-diabetic patients were observed (Table 1). However, the higher dialysate oxalate concentration was, the lower residual renal function was observed (r = - 0.69; p &amp;lt; 0.0001). Surprisingly, increased dialysate oxalate level was associated with low IL-6 (r = - 0.54; p = 0.002) (Fig. 1) and MCP-1 (r = - 0.7; p &amp;lt; 0.0001) (Fig. 2) concentrations in PDE. Conclusion To the best of our knowledge, the association between PDE oxalate excretion and proinflammatory mediators’ concentrations in PD patients has never been reported before. We suppose that peritoneal oxalate excretion might be involved in the intraperitoneal inflammation process. Further studies are needed to determine the possible pathogenetic role of dialysate oxalate removal in the conditions of intraperitoneal inflammation in PD patients.

P1507COMPETING RISKS MODELING IN PERITONEAL DIALYSIS: THE URGE FOR A CHANGE IN SURVIVAL ANALYSIS METHODOLOGY

Abstract Background and Aims Survival analysis is a cornerstone in medical research. For this purpose Kaplan-Meier is the most widely used statistical test, but the presence of competing risks violates the fundamental assumption that the censoring mechanism is independent of survival time. This leads to overestimation of the cumulative probability of cause-specific failure. Cumulative incidence estimate and competing risks analysis are preferred. The purpose of this study was to compare different survival analysis methods: Kaplan-Meier and cumulative incidence function estimates in a cohort of Peritoneal Dialysis (PD) patients. Method The survival of 115 incident patients on PD in a university hospital was evaluated after establishing 2 cohorts: patients starting renal replacement therapy with PD (PD first; n=85) and patients switching to PD on the first 6 months of dialysis (PD transfer; n=30). Kaplan-Meier, cumulative incidence function, cause-specific and subdistribution hazards were performed. The event of interest was death and the competing risk events were transfer to hemodialysis and renal transplantation. Results Besides higher residual renal function (RRF) and kt/V in the PD first group, there were no other significant differences between groups. There were 22 deaths. PD first group had a better survival with both Kaplan-Meier (log-rank test, p=0.013) and cumulative incidence function (p=0.021) approaches. The Cox regression model showed, as protecting variables, higher albumin (HR=0.174; CI95% 0.054-0.562), higher RRF (HR=0.785; CI95% 0.666-0.925) and PD first (HR=0.350; CI95% 0.132-0.927). Higher Charlson Index predicted worse outcome (HR=1.459; CI95% 1.159-1.835). PD as first dialysis therapy was associated with 65.0 % lower risk of death comparing with PD transfer. The subdistribution multivariable model found higher Charlson Index (HR=1.389; CI95% 1.118-1.725) and lower RRF (HR=0.798; CI95% 0.680-0.936) were statistically associated with death, but not PD transfer or albumin. This result differs from the obtained using the cause-specific hazard model. Analyzing the competing events, patients submitted to renal transplantation had a lower Charlson Index. Conclusion The probability of death was overestimated by the Kaplan-Meier method. The bias of Kaplan-Meier is especially great when the hazard of the competing risks is large. This study consisted on a statistical critical analysis of a real medical example, broader clinical conclusions related with “PD first initiative” should be cautious in this context. It is primordial to recognize the presence of competing risks in studies with multiple outcomes, as in Peritoneal Dialysis studies, to estimate cumulative incidence and yield more accurate results. This study shows how different conclusions are attained with different statistical methodology and its relevance in clinical context.

P1207ANALYSIS OF OUTCOME AND FACTORS ASSOCIATED WITH MAINTENANCE OF PERITONEAL DIALYSIS

Abstract Background and Aims Peritoneal dialysis (PD) is generally associated with a good survival rate and with great preservation of residual renal function (RRF). The various causes of technique failure are responsible for the relative short time staying in PD. Objectives: This study aimed to analyze the outcome and factors correlated with maintenance peritoneal dialysis (PD) to guide for improving prognosis. Method In a retrospective way we examined our PD-cohort concerning mortality, technique survival, peritonitis rate, and other complications. Results From 2005 to 2019 the number of PD patients who have been treated in PD program for more than 3 months was around 199 patient, 29.1% diabetics, mean age 53.3±15.03 years old and meantime in therapy 32.39± 27.34 months. The PD was seen as an alternative for younger patients in the transplant list and elderly patients with comorbidity. Around 7.5% of the PD patients were transplanted and 8.5 % of patients were transferred from HD due to vascular access failure. Around 88.9% of patients were on PD for more than 1 year, 37.7% from 3 up to 5 years and 19.8% percent of the patients have stayed on PD for more than 5 years. Cardiovascular mortality was the main cause of mortality with 53% of the cases. Higher comorbidity index, lower albumin levels, and lower residual renal function were the main risk factors for lower survival. The technical survival of patients was 92.3% during the first year, 79.5% and 69.6% in the second and the fifth year, respectively. There was not found a difference in technical survival between diabetics and nondiabetics patients. Ultrafiltration failure followed by peritonitis was the main reason for transfer patients with more than 24 months in therapy in hemodialysis probably linked with the no availability of icodextrin. Peritonitis rate was 1:41 patient months. Conclusion PD program in our center is organized based in the concept of integrated care in RRT. The outcome of our patients was at least comparable to those reported by larger registries Although we have done good progress in the prevention of infection the nonavailability of icodextrin is an important factor for a technical failure. RRF is an important factor and we need to be more focused to maintain it longer in the future.

Randomized controlled trial to compare the tolerability and efficacy of treatment with Icodextrin 7.5% versus Dextrose 2.5% in chronic peritoneal dialysis patients with high/high average solute transport characteristics and low residual renal function

Aim: Comparison of tolerability and efficacy of treatment with icodextrin vs. dextrose 2.5% amongst high risk cohort of chronic peritoneal dialysis patients (high/high average solute transport characteristics and low residual renal function) over 3 months. Study Design and Methodology: The study was an open-label, comparative, prospective, randomized controlled trial, conducted at department of Nephrology, Postgraduate Institute of Medical Education and Research, Chandigarh, India. A total of 349 end stage renal disease patients on chronic peritoneal dialysis were screened for eligibility over a period of 6 months and 41 patients with high / high average solute transport characteristics and low residual renal function were randomized to receive either icodextrin 7.5% solution or 2.5% dextrose solution in long dwell. Patients were assessed for adequacy of peritoneal dialysis (creatinine & urea clearance), peritoneal membrane transport characteristics including solute clearance (standard peritoneal equilibration test), body composition, total body water, fat mass and fat free mass (using whole body tetrapolar bioimpedance analyzer) at baseline and at the end of 3 months. Statistical Analysis: Continuous variables were compared with independent samples paired t test if normally distributed, or with Mann–Whitney U test if the distribution was skewed. Categorical variables were analyzed with Chi-square test or Fisher exact test as appropriate. Pearson's correlation coefficient was calculated between different quantitative variables. Paired t test and Wilcoxon signed-rank test were used for within-group comparisons. Repeated measure ANOVA was used to compare bioelectrical impedance between intervention groups. Results: The study has shown that use of icodextrin based continuous ambulatory peritoneal dialysis resulted in better ultrafiltration and improved solute clearance when compared to 2.5% dextrose based peritoneal dialysis in a select cohort of patients having high/high average transporter characteristics with poor residual renal function, however, it didn't significantly alter total body water and failed to translate into improvements in either patient's or physician's assessment of global health of response to therapy atleast at 3 months. Conclusions: Although use of icodextrin based peritoneal dialysis solution for long dwell resulted in significant improvement in solute clearance and ultrafiltration nevertheless failed to translate into better hydration status or subjective improvement scores atleast at 3 months.

A Fast Decline of Residual Renal Function in the First Year is a Predictor for Early Withdrawal from Peritoneal Dialysis in Non-Diabetic Patients

Background/Aims: Little is known about the relationship between residual renal function (RRF) decline in early period and survival in non-diabetic peritoneal dialysis (PD) patients. Methods: A total of 567 non-diabetic patients who began PD from January 1, 2005 to June 30, 2013 was investigated. The rate of RRF decline was determined by the “slope of the trend equation” of serial RRFs. A composite end-point of all-cause mortality and conversion to hemodialysis (HD) was used, survival status was censored on June 30, 2016. Results: The median of “the slope of RRF decline equation” was 0.308 (0.001-2.111) ml/min/1.73 m2/ month. In the median follow-up period of 43 months (range 12 to 120 months), 65 (11.5%) patients died, 90 (15.9%) patients converted to HD and 171 (30.2%) patients received kidney transplantation. Multivariate linear regression showed male, high baseline RRF, high baseline peritoneal Kt/V urea, low serum albumin and low uric acid were independently associated with the rate of RRF decline in the first year of PD. Multivariate Cox models revealed that RRF decline in the first year remained a predictor for composite end-point (HR, 2.74, 95% CI, 1.53 to 4.90, P=0.001). The patients were divided into high RRF decline group (> 0.308ml/ min/1.73m2/month) and low RRF decline group (≤0.308 ml/min/1.73m2/month). In the first three years of PD, the rate of end-point events was higher in high RRF decline group (23.2%) than that in low RRF decline group (11.0%) (P< 0.001). There were 189 patients in low RRF decline group and 171 patients in high RRF decline group maintaining PD for more than 3 years, in a median follow-up of 54 months (range 37 to 120 months), the survival rate was 30.9% in high RRF decline group and 46.4% in low RRF decline group (P=0.883). In high RRF decline group, there were 92 patients reaching composited end-point and 112 patients maintaining PD; multivariate Cox model showed high peritoneal Kt/V urea after 1 year of PD and high albumin level were protective factors (HR, 0.29, 95% CI, 0.13 to 0.61, P= 0.001; HR, 0.94, 95% CI, 0.90-0.99, P=0.022, respectively), while fast RRF decline remained risk factor for composite end-point (HR, 3.28, 95% CI,1.48-7.31, P=0.004). Conclusion: A faster RRF decline in the first year was a predictor for all-cause mortality and conversion to HD in non-diabetic PD patients, mainly in the first three year. For patients with faster RRF decline, increasing PD dose was effective to improve survival.

Effect of haemodialysis and residual renal function on serum levels of galectin-3, B-type natriuretic peptides and cardiac troponin T.

Levels of plasma markers of myocardial fibrosis (galectin-3), stretch (B-type natriuretic peptide (BNP)) and injury (high-sensitivity troponin T (hs-TnT)) are affected by haemodialysis, residual renal function (RRF) and cardiac pathology. We aimed to determine the association of RRF, urine output and haemodialysis itself on cardiac biomarkers in haemodialysis patients. Adult haemodialysis patients underwent venesection pre- and post-haemodialysis then echocardiography and inter-dialytic urine collection to calculate RRF (mL/min per 1.73m2 ) and urine output (mL/day). Galectin-3, BNP-32, NT-ProBNP and hs-TnT levels were compared across tertiles of echocardiographic parameters, RRF and urine output using the non-parametric test for trend across ordered groups. Twenty-three patients (17 male) with mean age 67.7±13.8 years and median (interquartile range) dialysis duration 13.6 (9.8-19.1) months participated. Galectin-3 was substantially lower following haemodialysis: 55 ng/mL (47-70) versus 23 ng/mL (19-27, P < 0.001), but other biomarkers changed little. By increasing RRF tertile, post-dialysis galectin-3 was 32.6 ng/mL (23.7-36.6), 21.9 ng/mL (19.0-23.2) and 19.0 ng/mL (16.9-21.0, P = 0.001); NT-ProBNP was 10 192 ng/L (2303-21 504), 2037 ng/L (1224-10 795) and 1481 ng/L (172-2890, P = 0.016). Results were similar for daily urine volume, but measured echocardiographic parameters were not associated with biomarker concentrations. Plasma concentration of galectin-3 is reduced by the haemodialysis procedure. Lower RRF and urine volume are strongly associated with higher levels of galectin-3 and NT-Pro-BNP. These associations are important to the clinical interpretation of these biomarker levels in haemodialysis patients.

The Association of Longitudinal Serum Uric Acid and All-Cause Mortality in Incident Peritoneal Dialysis Patients

Background: Time-averaged uric acid (TA-UA) value was calculated to investigate the association of longitudinal UA and all-cause mortality in incident peritoneal dialysis (PD) patients. Methods: Three hundred PD patients were divided into 3 groups based on the serum TA-UA level (Group 1: < 6 mg/dL; Group 2: 6–8 mg/dL; Group 3: ≥8 mg/dL). Hazards ratio (HR) of all-cause mortality was calculated. Logistic regression was conducted to identify the associated clinical factors of lower and higher TA-UA level. Results: Increased HRs for death existed in Group 1 and Group 3 compared with Group 2 (HR 3.24, 95% CI 1.25–8.39, p = 0.016; HR 4.69, 95% CI 1.24–17.72, p = 0.023). Lower residual renal function, lower albumin, and higher high-density lipoprotein cholesterol were related to the lower serum TA-UA. Higher body mass index and higher C-reactive protein were associated with higher serum TA-UA in PD patients. Conclusion: Both TA-UA < 6 and ≥8 mg/dL increased the all-cause mortality in incident PD patients.

A15199 Resistant hypertension in dialyzed patients- how to define it properly

Objectives: Hypertension (HTN) is an overwhelming finding in dialysis patients and the blood pressure (BP) control is often very poor in this group. Resistant hypertension is defined as inability to reach blood pressure below 140/90 mm Hg despite treatment with 3 hypotensive drugs including diuretic. The etiology of HTN in end-stage renal disease is multifactorial. The aim of the study was to assess blood pressure control in 104 hemodialysis (HD group) and 64 peritoneal dialysis (PD group) patients. Methods: The medical history, BP measurements, residual diuresis, laboratory tests, the presence of peripheral edema type of hypotensive therapy, the presence of volume overload, the presence of residual diuresis and BP control was analyzed. Results: HD patients were significantly older than PD group (Me = 64 vs. Me = 57,5y, p < 0,05) with longer dialysis vintage (p < 0,05), with lower diastolic BP, lower residual renal function (44% vs. 62%, p < 0,05). Prevalence of resistant hypertension was 44% in HD population and 63% in PD (p < 0.01). The peripheral edema was observed significantly more often in PD group with uncontrolled BP (above 140/90 mmHg) (72,2% vs 35,7%, p < 0,05). The average amount of hypotensive drugs was 3 in HD and 4 in PD patients. The most used hypotensive drug was beta-blocker. PD patients were treated with ACEi and ARB significantly wider (p < 0,05). Conclusion: BP and volume control are more satisfactory in HD group. However, definition of resistant hypertension in dialyzed patients should be modified accordingly as diuretics are not used in patients without residual renal function. It should be also stated which BP measurements are valid for definition of resistant hypertension (before, after, between HD).

Ultrafiltration rate in conventional hemodialysis: Where are the limits and what are the consequences?

Ultrafiltration rate (UFR) has attracted attention as a modifiable aspect of volume management. The objective of this review is to summarize the evidence that links UFR to patient outcomes and discuss UFR cut-offs proposed, and discuss possible consequences of adapting UFR as a quality metric. Higher UFRs has been associated with younger age, longer dialysis vintage, greater prevalence of comorbidities, higher Kt/V, lower weight, greater interdialytic weight gain, lower residual renal function, and shorter treatment times. Many of the characteristics associated with high UFRs have also been independently associated with poor patient outcomes. Four observational studies have assessed the association between UFR and patient mortality. All of them reported an association between higher UFR and greater patient mortality, though the studies differed in their definition of UFR, follow-up, and adjustment for confounding. Evidence for the association between higher UFR and potential mediations of the mortality association, such as interdialytic hypotension, cardiac remodeling, and cardiovascular events was less consistent. There was a graded association between higher UFRs and all-cause mortality; no definitive cut-off for acceptable UFR can be established based on the current evidence. Targeting UFR in isolation might result in volume expansion and worsening patient outcomes. Residual confounding likely contributed to the findings of the observational studies. No randomized controlled trials addressed the questions. Evidence supporting UFR limits is weak and confounded. Randomized controlled trials are needed before UFR can be used as a quality of care indicator.

Residual Renal Function and Obstructive Sleep Apnea in Peritoneal Dialysis: A Pilot Study.

Obstructive sleep apnea is common in patients with end-stage renal disease, and there is increasing evidence that clinical factors specific to end-stage renal disease contribute pathophysiologically to obstructive sleep apnea. It is not known whether circumstances specific to dialysis modality, in this case peritoneal dialysis, affect obstructive sleep apnea. Our study aimed to investigate the prevalence of obstructive sleep apnea in the peritoneal dialysis population and the relevance of dialysis-specific measures and kidney function in assessing this bidirectional relationship. Participants with end-stage renal disease who were treated with nocturnal automated peritoneal dialysis for at least 3 months were recruited from a hospital-based dialysis center. Laboratory measures of dialysis adequacy, peritoneal membrane transporter status, and residual renal function were gathered by chart review. Patients participated in a home sleep apnea test using a level III sleep apnea monitor. Of fifteen participants recruited, 33% had obstructive sleep apnea diagnosed by apnea-hypopnea index ≥ 5 events per hour of sleep. Renal creatinine clearance based upon 24-h urine collection was negatively correlated with apnea-hypopnea index (ρ = - 0.63, p = 0.012). There were no significant associations between anthropometric measures, intra-abdominal dwell volume, or peritoneal membrane transporter status and obstructive sleep apnea measures. The prevalence of obstructive sleep apnea and sleep disturbances is high in participants receiving peritoneal dialysis. Elevated apnea-hypopnea index is associated with lower residual renal function, whereas dialysis-specific measures such as intra-abdominal dwell volume and peritoneal membrane transporter status do not correlate with severity of obstructive sleep apnea.

Acid base status of prevalent peritoneal dialysis patients

Acid-base status of patients on peritoneal dialysis is influenced by multiple factors. Metabolic acidosis is a common feature of chronic renal failure and dialysis treatment provides alkali in the dialysate in order to maintain a normal acid-base balance. This paper reports the prevalence of acid-base disorders in peritoneal dialysis patients and their associations with clinical and laboratory parameters. This is a cross-sectional retrospective study that included all PD patients registered in the RDPLF database. Metabolic acidosis was found in 20.4% of patients while 27.8% of patients had metabolic alkalosis. There is a significant relationship between age, protein intake estimated by nPNA and the level of alkaline reserve pleading in favor of the influence of dietary intakes in the maintenance of metabolic acidosis. Low residual renal function is associated with a lower probability of being in metabolic alkalosis. These results could allow an individual choice of the dialysate buffer in order to permanently obtain stable acid-base status in patients on peritoneal dialysis.