Incident Peritoneal Dialysis Patients Research Articles

Impact of home-based exercise on residual kidney function in patients initiating peritoneal dialysis: A feasibility multicenter randomized controlled trial.

Although the impact of aerobic exercise (AE) and resistance training (RT) on peritoneal dialysis (PD) patients is well established, the impact of exercise programs on residual kidney function (RKF) has not been elucidated. Patients were randomly assigned to either the exercise (n = 25) or control groups (n = 30). Patients in the exercise group performed AE three times a week and RT twice a week at home for 24 weeks. The control group did not receive any specific intervention. The primary outcome was RKF, assessed by residual glomerular filtration rate (rGFR). Secondary outcomes included urinary protein levels, distance covered in the incremental shuttle walking test (ISWT), and glycated hemoglobin (HbA1c) percentages. Linear mixed-effects models showed no significant changes in mean rGFR between the exercise and control groups at 12 weeks (-0.40; 95% confidence interval (CI): -2.17, 1.36; p = 0.65) and at 24 weeks (0.65; 95% CI: -1.15, 2.45; p = 0.48). There was a trend toward improvement in mean urinary protein level and ISWT results, and a significant decrease in mean HbA1c percentage at 24 weeks in the exercise group (-1.07, 95% CI: -2.29, 0.15, p = 0.09; 37.7, 95% CI: -10.1, 85.5, p = 0.12; -0.57, 95% CI: -0.97, -0.18, p = 0.005, respectively) compared to the control group. The 24-week home-based exercise program did not demonstrate beneficial effects on RKF in incident PD patients. Nonetheless, it may have an impact on reducing urinary protein levels and HbA1c percentages.

Lower risk of the deterioration of muscle mass and function in oral active vitamin D users among Incident peritoneal dialysis patients: a 12-month follow-up cohort study

Data in terms of how active vitamin D supplementation affects muscle mass and function in end-stage renal disease (ESRD) patients has led to inconclusive results. The main goal of this research was to examine the association of active vitamin D supplementation and risk of the deterioration of muscle mass and function among ESRD patients on peritoneal dialysis (PD). Eligible ESRD patients on PD were prospectively included, and followed up at 3-month intervals in the tertiary care center. Based on the medications during the 12-month follow-up period, the patients were divided into two groups (vitamin D users and non-users). The deterioration of muscle mass and function was identified utilizing the criteria set by the Asian Working Group on Sarcopenia in 2019 (AWGS 2019). Primary outcome was defined as the deterioration of muscle mass and function at the end of the 12-month follow-up. The absolute diffecence and 95% confidence interval (CI) of the incidence of deterioration between vitamin D users and non-users was estimated. The association of vitamin D supplementation with risk of the deterioration of muscle mass and function during the 12-month follow-up period, was examined by employing multivariate logistic regression models. A total of 229 incident PD patients (6 of whom were lost in follow-up) were included. During the entire study period, 54.7% (122/223) of the remaining patients were considered users of oral active vitamin D. The incidence of deterioration in muscle mass and function was 30.5% (68/223) throughout the entire follow-up. In this regard, the rate was 23.0% (28/122) that received oral active vitamin D, while it was 39.6% (40/101) in the group that did not receive it, with an absolute diffecence of -16.6% (95% CI − 4.5, − 28.7) and an estimated relative risk (RR) of 0.784 (95% CI 0.651–0.943). After adjustment for potential confounding factors in logistic regression model, vitamin D users group was still associated with decreased risk of the deterioration of muscle mass and function (OR 0.330, 95% CI 0.159–0.683, P = 0.003). In secondary analysis, the relationship between oral active vitamin D and the deterioration of muscle mass and function remained consistent (≤ 0.25 µg per day vs. non-users; OR 0.300, 95% CI 0.131–0.688, P = 0.004); however, no significant relationship was identified in patients receiving a mean daily dose of > 0.25 µg compared with non-users (OR 0.389, 95% CI 0.146–1.034, P = 0.058). These results indicate that active vitamin D supplementation was significantly associated with a decreased risk of the deterioration of muscle mass and function in incident PD patients with ESRD. However, the amount and type of vitamin D used and the duration of the intervention warrant further randomized controlled trials to confirm the possibility that such medication improves sarcopenia in ESRD patients.

The Role of Kt/V and Creatinine clearance on Assisting Optimization of Serum Phosphorus Levels among Patients on PD.

Hyperphosphatemia is associated with poor outcome and is still very common in peritoneal dialysis (PD) patients. Since peritoneal phosphate clearance is closer to peritoneal creatinine clearance than urea clearance, we hypothesized that weekly creatinine clearance (CrCl) could be a better marker of serum phosphate in PD. In a retrospective observational study, data from adult PD patients were collected across five institutions in North and South America: LATAM, RRI, Mount Sinai Hospital, Hospital Civil de Guadalajara, and the BRAZPD cohort. All centers analyzed routinely available laboratory data, with exclusions for missing data on serum phosphate, CrCl, or urea Kt/V. A unified statistical protocol was employed across centers. Linear mixed-effect models examined associations between longitudinal serum phosphate levels, CrCl, and Kt/V. Adjustments were made for age, gender, and baseline phosphate binder usage. Mixed-effects meta-analysis determined the pooled effect size of CrCl and Kt/V on serum phosphate trajectories, adjusted for confounders. There were 16,796 incident PD patients analyzed. Age, BMI, gender, PD modality, Kt/V and CrCl as well as serum phosphate varied significantly across the different cohorts, but >70% had residual renal function. For most cohorts, both CrCltotal and urea Kt/V associated negatively with serum phosphorus levels, and log-likelihood ratio tests demonstrate that models including CrCltotal have more predictive information than those including only urea Kt/V for the largest cohorts. Models including CrCltotal increase information predicting longitudinal serum phosphate levels irrespective of baseline urea Kt/V, age, use of phosphorus binder, and gender. CrCl was not more accurate in predicting serum phosphate than urea Kt/V, but its inclusion in multivariable models predicting serum phosphate added accuracy. In conclusion, both creatinine clearance and Kt/V are associated with phosphate levels, and using both biomarkers, instead of just one, may better assist in the optimization of serum phosphate levels.

Iron Deficiency Increases Mortality Risk among Incident Peritoneal Dialysis Patients

Iron Deficiency Increases Mortality Risk among Incident Peritoneal Dialysis Patients

Modified creatinine index as a marker of skeletal muscle mass in peritoneal dialysis patients.

Sarcopenia is common in peritoneal dialysis (PD) patients. Modified creatinine index (MCrI) by the Canaud's formula and single-pool Kt/V value is an accurate surrogate marker for muscle mass in hemodialysis patients. However, the method of calculation and validity of MCrI has not been tested in PD. In the exploratory cohort, we studied 138 consecutive patients converted from PD to hemodialysis. Their MCrI during PD, calculated by the Canaud's formula with total weekly Kt/V, and the conventional MCrI after conversion to HD, were compared by the Bland-Altman method. Their correlation with muscle mass as determined by bioimpedance spectroscopy and creatinine kinetic methods was explored. The result was then validated in a second cohort of 605 incident PD patients. In the exploratory cohort, the average bias of computing MCrI during PD and hemodialysis was 0.758mg/kg/day (95%CI -4.356 to 5.873mg/kg/day). The MCrI during PD significantly correlated with the muscle mass by creatinine kinetics (r=.684, P<.0001) and by bioimpedance spectroscopy (r=.641, P<.0001), but not with protein nitrogen appearance, overhydration, or adipose tissue mass, and the result was similar in the validation cohort. For incident PD patients, MCrI quartile was significantly associated with the risk of death from all cause in 12 months (Gray's test, P=.013) but not conversion to chronic hemodialysis (P=.14). In PD patients, MCrI computed by the Canaud's formula and total weekly Kt/V is a simple and reliable marker of skeletal muscle mass and may serve as a short-term prognostic indicator.

Higher Platelet Count Mostly in the Normal Range Is Associated with the First Episode of Peritonitis Risk in Incident Peritoneal Dialysis Patients

Introduction: Platelets play parts in infection and immune processes. However, the association between platelet count and the risk of peritoneal dialysis (PD)-associated peritonitis is unclear. Methods: This was a retrospective, observational, single-center cohort study. A Cox regression analysis was used to evaluate the independent association of platelet count with the occurrence of first PD-associated peritonitis. Models were adjusted for gender, age, body mass index, cardiovascular disease, diabetes mellitus, white blood cell count, neutrophil-lymphocyte ratio, hemoglobin level, albumin level, potassium level, and anti-platelet medication usage. Results: A total of 2,374 patients were enrolled in this study (59% men; mean age 47.40 ± 12.12). The average platelet count was 229.30 ± 82.12 × 109/L. 467 (20%) patients suffered from PD-associated peritonitis at least once. In the multivariable model, the adjusted hazard ratios (HRs) for quartiles 2, 3 and 4 versus quartile 1 were 1.428 (95% CI 1.060–1.924, p = 0.019), 1.663 (95% CI 1.240–2.229, p < 0.001) and 1.843 (95% CI 1.363–2.492, p < 0.001) with baseline data. A nonlinear relationship between platelet count and first PD-associated peritonitis was observed. Further, the association between platelet and first PD-associated peritonitis was significant in the patients with hypokalemia (P for interaction = 0.040). Conclusion: In PD patients, elevated platelet counts were significantly associated with an increased risk of the first onset of PD-associated peritonitis.

The Time-Dependent Effect of Assistance on Peritoneal Dialysis Duration: An Analysis of Data from the French Language Peritoneal Dialysis Registry.

Key Points It is unknown whether the benefit of assisted peritoneal dialysis (PD) programs appears immediately after PD initiation or rather after some time spent on PD.The protective effect of assisted PD on the risk of transfer to hemodialysis was not constant over time; it started after the first 6 months on PD.Assisted PD programs should be sustainable for at least 6 months to observe their benefits. Background Peritoneal dialysis (PD) patient compliance is crucial for the prevention of complications. Assistance is associated with a lower risk of transfer to hemodialysis. As the risk of noncompliance increases over time, the protective effect of assistance on the risk of transfer to hemodialysis may not be immediate after PD initiation, but rather may appear after some time on PD. We aimed to analyze the time-varying effect of assistance on the risk of PD cessation. Methods This retrospective study was conducted using data from the French Language PD Registry of incident PD patients between 2002 and 2018. Because of nonproportional hazards, with a change in the effect of the assistance modality on the different outcomes appearing at 6 months after PD initiation, the associations between the assistance modality and the different outcomes were explored using time-dependent coefficient Cox regression. Results The study included 15,675 patients; 6717 deaths, 4973 transfers to hemodialysis, and 3065 kidney transplantations occurred. Both patients receiving nurse- and family-assisted PD had a lower risk of transfer to hemodialysis (mean cause-specific hazard ratio [cs-HR], 0.67; 95% confidence interval [CI], 0.62 to 0.72; and mean cs-HR, 0.75; 95% CI, 0.67 to 0.84). In the first 6 months after PD initiation, nurse-assisted PD patients had a greater risk of transfer to hemodialysis (&lt;6 months cs-HR, 1.18; 95% CI, 1.03 to 1.36) but had a lower likelihood afterward (≥6 months cs-HR, 0.57; 95% CI, 0.53 to 0.62). Family-assisted PD was not associated with the risk of transfer to hemodialysis in the first 6 months after PD initiation, and those patients had a lower risk of transfer to hemodialysis afterward (≥6 months cs-HR, 0.72; 95% CI, 0.63 to 0.82). Conclusions When implementing a national nurse-assisted PD program, its positive impact on PD duration should not be expected immediately after PD initiation. Assisted PD programs should be sustainable for at least 6 months to observe their benefits. Podcast This article contains a podcast at https://www.asn-online.org/media/podcast/K360/2024_10_31_KID0000000577.mp3

Serum Soluble Suppression of Tumorigenicity-2 Levels Predict Cardiovascular Events in Patients Undergoing Incident Peritoneal Dialysis: A Prospective Cohort Study.

Biomarkers are urgently required to identify peritoneal dialysis (PD) patients at risk of cardiovascular (CV) events. This study aimed to investigate the predictive value of soluble suppression of tumorigenicity-2 (sST2) for CV events in patients undergoing incident PD. In this prospective cohort study, incident PD patients were enrolled. Blood samples to measure sST2 levels were obtained before PD catheter implantation. The patients underwent a standard peritoneal equilibration test (PET) after initiation of PD for 4-6 weeks. The sST2 levels in both serum and dialysate were determined using enzyme-linked immunosorbent assay. CV events were recorded during the follow-up period. A total of 137 patients were enrolled. During the follow-up period of 17.3 months, 49 (35.76%) patients experienced CV events. When patients were dichotomized based on the median values and the calculated cutoff values of sST2, the higher sST2 group had 2.980- and 3.048-fold increased risks of CV events, respectively, when compared with the lower sST2 group. Moreover, the prognostic value of sST2 remained significant as a continuous variable (per 1 standard deviation increase, hazard ratio [HR] = 1.037, 95% confidence interval [CI] 1.010-1.066, p = 0.008). N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were found to indicate a higher risk only when dichotomized based on the calculated cutoff values. Furthermore, serum sST2 and NT-proBNP levels simultaneously above the calculated cutoff values were associated with a higher risk of CV events (HR = 3.398, 95% CI 1.813-6.367, p &lt; 0.001). Baseline serum sST2 level is an independent predictor of the risk of CV events in patients receiving incident PD, and in combination with NT-proBNP level, it can provide a more accurate predictive value.

Early Anuria in Incident Peritoneal Dialysis Patients: Incidence, Risk Factors, and Associated Clinical Outcomes

Rationale & ObjectiveThe development of anuria was linked to worse clinical outcomes in patients undergoing peritoneal dialysis (PD). Our objective was to investigate the incidence, risk factors, and associated clinical outcomes of anuria within the first year after PD. Study DesignRetrospective Cohort Study. Setting & ParticipantsPatients who started continuous ambulatory peritoneal dialysis (CAPD) at our center between 2006 and 2020 were included and followed up until January 31, 2023. ExposureAge, gender, diabetes, temporary hemodialysis, angiotensin-converting enzyme inhibitors (ACEI)/angiotensin II receptor blockers (ARBs), diuretics, baseline urine volume, serum albumin, daily glucose exposure, peritonitis, and incremental PD. OutcomesThe primary outcome was early anuria, defined as 24-hour urine volume ≤ 100mL within the first year of PD initiation. Secondary outcomes included all-cause mortality, cardiovascular disease (CVD) mortality, technique failure, and peritonitis. Analytical ApproachCox proportional hazards model. ResultsA total of 2592 CAPD patients aged 46.7 ± 14.9 years were recruited. Among them, 58.9% were male, 24.0 % had diabetes. Within the first year of PD therapy, 159 (6.13%) patients developed anuria, with a median duration of 7.53 (interquartile range [IQR] 3.93-10.0) months. Higher baseline urine volume (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.90-0.97), higher serum albumin (HR 0.92, 95% CI 0.88-0.95), with diabetes before PD (HR 0.57, 95% CI 0.35-0.92), and prescribed incremental PD (HR 0.27, 95% CI 0.14-0.51) were associated with a reduced risk for early anuria, while a higher level of daily glucose exposure (HR 1.01, 95% CI 1.00-1.01) was identified as a risk factor for early anuria. Subgroup analyses showed that using ACEI/ARBs was linked to a lower risk of early anuria (HR 0.25, 95% CI 0.09-0.69) in diabetic patients. Treating early anuria as a time-dependent covariate, early anuria was associated with a higher risk for all-cause mortality (HR 1.69, 95% CI 1.23-2.32) and technique failure (HR 1.43, 95% CI 1.00-2.04) after adjusting for confounding factors. LimitationsSingle-center and observational study. ConclusionsThe incidence of early anuria in our center was 6.13%. Higher baseline urine volume, higher serum albumin, a history of diabetes, incremental PD start, and lower daily glucose exposure were associated with lower risks of early anuria. In patients with diabetes mellitus, non-use of ACEI/ARBs was associated with early anuria. Early anuria was related to a higher risk for all-cause mortality and technique failure.

#1085 Prediction models for hospitalization in patients with advanced chronic kidney disease: systematic review, external validation and development study

Abstract Background and Aims Hospitalization is a common complication in patients with advanced chronic kidney disease (CKD). Predicting hospitalization would be beneficial for clinicians and patients. Clinicians may be assisted in adequate healthcare planning by being able to anticipate hospitalizations. Additionally, patients have indicated wanting more information about their risk of hospitalization. By providing patients a personal indication of their risk of hospitalization, they better know what to expect of the future which can foster a feeling of control. Especially for incident dialysis patients this might help, as they enter a new and to them still largely unknown stage of their disease. Moreover, if a patient knows they have a high risk of hospitalization, they may better cope with the hospitalization if it occurs, as it is less unexpected. Therefore, we aimed to 1) identify and give an overview of current prediction models for hospitalization in CKD patients, 2) externally validate these models, and 3) develop a new model if no well-performing models were identified. Method We performed a systematic review in PubMed to identify prediction models for hospitalization, length of stay (LOS), and readmission. Identified models were appraised using the Prediction model Risk of Bias Assessment Tool. We targeted three external validations in hemodialysis (HD), peritoneal dialysis (PD), and pre-dialysis patients in a Dutch dialysis and European pre-dialysis cohort. Prediction models were externally validated on discrimination (C-statistic) and calibration (calibration plot, slope, and calibration-in-the-large). We developed a Fine-Gray model for hospitalization within one year in patients initiating HD, taking into account the competing risk of death. Informed by model performance, we also investigated Cox and logistic regression as modeling strategies. We performed a sensitivity analysis, redefining the outcome to be predicted as the 1-year risk of hospitalization of 3 days or longer. Results From the systematic search, we identified 17 models in 6 studies. All models were developed in the USA or in China. Two models predicted hospitalization rate in incident PD patients and 3 models predicted 30-day readmission in maintenance HD patients and in CKD stage 3-5 patients not on dialysis discharged after a heart failure hospitalization. The risk of 1 and 6 hospitalizations within one year in prevalent HD patients were predicted by one model each. Prolonged LOS in PD patients was predicted by ten models. All models were of low quality with a high risk of bias. The most common shortcomings were using future information to make predictions, inadequate handling of missing data, and model overfitting. Due to underreporting and unavailability of predictors, we could only externally validate 3 models. These models were poorly calibrated and had poor discrimination. We developed a new model in 1,020 incident HD patients predicting 1-year risk of hospitalization. We used age, cardiovascular disease, diabetes mellitus, malignancy, estimated glomerular filtration rate, and body mass index as predictors, selected based on literature and clinical expertise. The model discriminated poorly (C-statistic, 95% confidence interval [CI]; 0.55, 0.53-0.58), also in targeted external validations in 620 PD patients (0.55, 0.52-0.58) and 1,718 pre-dialysis patients (0.52, 0.52-0.54). Calibration was poor for all models. Using different modelling strategies, model performance did not improve. In the sensitivity analysis, discrimination improved but was still low (HD population: 0.58, 0.55-0.62; PD population: 0.59, 0.54-0.63; pre-dialysis: 0.55, 0.52-0.57). Conclusion Hospitalizations are important but difficult to predict for patients with advanced CKD. Current models are insufficient to predict hospitalizations. We offer two main suggestions to improve future predictions of hospitalizations. First, the outcome of hospitalization should be more specific (e.g., cardiovascular hospitalizations) to reduce outcome heterogeneity. Second, the selection of predictors should be extended with more patient-centered factors, such as patient-reported outcomes.

#2495 Renal and peritoneal protective effects of SGLT2 Inhibitors in incident peritoneal dialysis (PD) patients

Abstract Background and Aims The renoprotective effect of SGLT2 inhibitors has been evaluated in several large studies, but renal function of the subject is defined as eGFR≥20-30 mL/min/1.73 m2 or higher in most studies. On the other hand, SGLT2 is expressed in the peritoneum, and there have been reports of decreased glucose absorption and improvement of ultrafiltration injury with SGLT2 inhibitors in animal studies. However, there are very few reports on the protective effects of SGLT2 inhibitors on renal and peritoneal function in PD patients. In the present study, we retrospectively evaluated the renal and peritoneal protective effects of SGLT2 inhibitors in patients undergoing PD. Method Among the patients who received PD at our hospital, 8 patients who continued SGLT2 inhibitors and underwent peritoneal equilibrium testing (PET) at the time of induction and 1 year after induction were assigned to the SG group, and 32 patients who received PD without SGLT2 inhibitors were assigned to the control group. PET data, PD drainage volume, urine output, renal • peritoneal • total Kt/V, and renal • peritoneal • total weekly CCr at the time of PD induction and 1 year after PD induction were compared retrospectively. Results Among the 40 patients, the median age was 64 years (interquartile range 52-71), with 33% males, and the median eGFR at PD induction was 5.25 ml/min/1.73 m2. The most common cause of end-stage renal failure was diabetic nephropathy (37.5%), followed by chronic glomerulonephritis (15.0%) and nephrosclerosis (12.5%). At the time of induction of peritoneal dialysis, there were no significant differences between the SG group and the control group in PET data, PD drainage volume, urine output, renal • peritoneal • total Kt/V and weekly CCr. However, at one year after PD induction, urine volume, renal • total Kt/V, and renal weekly CCr were higher in the SG group. Total weekly CCr at 1 year of PD induction was significantly higher in the SG group (p = 0.03). Multivariate linear regression analysis showed that SGLT2 inhibitors were independently associated with total weekly CCr at 1 year after PD induction (p = 0.04). Conclusion Our results suggest that SGLT2 inhibitors may have renal and peritoneal protective effects in patients undergoing PD induction. For CKD stage G4 and 5 patients scheduled for PD induction in the future, proactive continuation of SGLT2 inhibitors may be effective in preserving renal and peritoneal function.

#494 Analysis of technique failure and reasons for the end of follow-up in a peritoneal dialysis unit

Abstract Background and Aims Currently, there are various definitions for peritoneal dialysis technique failure, and several related factors are described. There is controversy regarding whether mortality should be considered a form of technique failure or not, as it involves an event of a different nature. Besides, the exit form peritoneal dialysis (PD) technique can occur due to the transition to hemodialysis (HD), kidney transplantation or the patient's death in general. The aim of this study was to investigate which factors are associated with survival in peritoneal dialysis technique. Method A retrospective study was conducted with 111 incident PD patients in the dialysis unit of Hospital Universitario Virgen de las Nieves, in Granada, Spain, between 2015 and 2020. A survival curve was obtained, evaluating the association of different variables with technique failure and the end of follow-up. By identifying mortality as a competitive risk for technique failure, a Fine and Gray competitive risks model was applied. Results A total of 111 patients were analyzed, with an annual technique survival of 90%, being it 83% at two years, and 74% at three years. Table 1 reflects the demographic and clinical characteristics of the patients. The main causes of technique failure were psychosocial causes (19%), peritoneal catheter mechanical issues (12%), ultrafiltration failure (9.52%), and peritonitis (9.52%). The main reasons for the end of follow-up were kidney transplantation (55%), transfer to HD (26%), and death (12.6%). Among the deceased, 64% were of cardiovascular origin, and 21% were infectious. Technique failure was more observed in patients over 65 years old, in those with a Charlson index higher than 4 points, with diabetes, a history of cardiovascular disease (CVD) and heart failure (HF), in former smokers, and in diabetic kidney disease. Conclusion Technique survival in our center was 90% at one year and 83% at two years, similar to previous Spanish records. The reasons for technique exit were: 55% due to kidney transplantation, 26% due to transfer to hemodialysis, and 19% due to for psychosocial causes. Risk factors related to technique failure were advanced age, Charlson index, diabetes, and a history of cardiovascular disease (CVD) and heart failure (HF).

#521 Increasing levels of aortic peak wave velocity along with prolonged higher CaxP product is associated with mortality in peritoneal dialysis

Abstract Background and Aims Valvular calcification is concordant with vascular calcification and develops faster in end-stage renal disease patients than in the average population. There are contradictory reports about the pathophysiology and the predictive value of valvular calcification regarding mortality in this patient population. Aortic peak wave velocity (Vmax) measurement is a non-invasive and reliable marker for the diagnosis of valve calcification. Our study analyzes cardiovascular risk prediction effect of increasing levels of Vmax at different time points in peritoneal dialysis (PD) patients. Method We conducted a retrospective, single-center study of incident PD patients under follow-up between January 1992 and January 2023 in our clinic. Demographics, laboratory, and echocardiographic findings were obtained from medical records. Patients without a baseline echocardiography were excluded. ΔVmax is defined as the last Vmax minus baseline Vmax levels. The patients were divided into two subgroups: Vmax-stable and Vmax-increased. Results The baseline demographics, laboratory, and clinical characteristics, including daily elemental calcium and calcitriol usage, were similar between Vmax-stable and Vmax-increased groups. Baseline calcium (Ca), phosphate (P), and annual CaXP levels were significantly higher in Vmax-increased group [p = 0.01, p = 0.02, and (F(1,27) = 10.415, p = 0.003), respectively]. Cardiovascular mortality was 9.8% in Vmax-stable group and 26.8% in Vmax-increased group (p = 0.02). Conclusion During a follow-up of 20 years, increasing Vmax values were associated with higher CaxP levels in PD patients. Increased Vmax levels, along with higher CaxP levels, are associated with cardiovascular mortality. Even without clinical manifestations, Vmax follow-up is a non-invasive, easily accessible method and might identify the high-risk group regarding cardiovascular mortality in the PD population.

#988 Peritoneal dialysis related peritonitis: insights from a long-term analysis of an Italian center

Abstract Background and Aims Peritonitis is a common and severe complication of peritoneal dialysis (PD). For comparative analysis standardized definitions are crucial, but most studies have been used heterogenous methods to measure outcomes. The ISPD 2022 guidelines have revised and clarified numerous definitions and proposed new peritonitis categories. Thus, deeper comprehension concerning the incidence, prevalence, and outcome of cause- and time specific peritonitis in contemporary cohorts is required. Method Between 1st January 2009 and 31st May 2023, 267 patients who started PD at our institution were included in the study (Tab. 1). All PD-related peritonitis episodes that occurred in our unit during the study period were collected. The new definitions and outcomes of ISPD 2022 recommendations were employed. Results During the study period 113 patients (42.3%) experienced 219 peritonitis (Tab. 2). The overall peritonitis rate was 0.25 episode/patient year. During the study period, 230 patients (88.5%) discontinued the dialytic technique; among them 122 were transferred to HD. Peritonitis represented the main cause of hemodialysis (HD) transfer (35.2%). Patient cumulative probability of remaining peritonitis-free at one year was 84.2%. The initial antibiotic regimen (cefazolin in association with tobramycin ip) was effective in 131 episodes (141/219, 64.3%), while the medical cure and refractory peritonitis rates were equal to 70.3 and 22.4%, respectively. The rates of peritonitis associated death, HD transfer, catheter removal and hospitalization were 6.8%, 18.3%, 18.7% and 64.4%, respectively. Relapsing, repeat, recurrent and enteric peritonitis accounted for 7.8%, 6.8%, 4.1% and 2.7% of all episodes, respectively. Catheter insertion, catheter related and pre-PD peritonitis were 4.2, 2.1 and 0.5%. Gram-positive and Gram-negative bacteria accounted for 74.1% and 21.3% of peritonitis, respectively. Initial antibiotic regimen was more effective in Gram-positive (76.4%) than Gram-negative (35.1%) microorganisms (p &amp;lt; 0.0001). Culture-negative peritonitis accounted for 25.6% of all specimens. In comparison with positive-culture peritonitis, culture-negative episodes showed a higher medical cure rate (88.4%, 46/52 vs 68.9%, 104/151; p &amp;lt; 0.01) and were significantly less likely to be complicated by hospitalization (48.1%, 25/52 vs 72.2%, 109/151; p &amp;lt; 0.05), catheter removal (9.6%, 5/52 vs 22.5%, 34/151; p &amp;lt; 0.05), HD transfer (9.6%, 5/52 vs 21.9%, 33/152; p &amp;lt; 0.05) and death (0%, 0/52 vs 8.6%, 13/151, p &amp;lt; 0.05). However, initial antibiotic regimen response was similar between culture-negative and culture-positive episodes (71.2%, 37/52 vs 62.3%, 94/151, p = ns). Rates of relapsing, repeat and recurrent peritonitis were 0.023, 0.018 and 0.011 episode/patient-year, respectively accounting for 7.8, 6.8 and 4.1% of all episodes The composite outcome of either catheter removal or death due to peritonitis was higher in relapsing (42.1%, 8/19, p &amp;lt; 0.05) and recurrent (44.4%, 4/9, p &amp;lt; 0.05) episodes than generic peritonitis (19.1%, 34/178) but similar to repeat peritonitis (3/15, 20%, p = ns). Although peritonitis from enteric causes represented only 2.7% of all episodes, they needed catheter removal in one-third of events (33.3%) and caused patient death (66.6%) in the remaining cases. Conclusion Although representing the leading cause of HD transfer cause, more than 50% of incident PD patients never experienced peritonitis. Carrying a worse outcome than generic peritonitis, entities such as relapsing, recurrent and enteric peritonitis should be aggressively treated. Conversely, culture-negative peritonitis showed a better prognosis as compared to positive-culture episodes. However, aiming at the prevention of microbial resistances, the reduction of culture-negative cases is necessary to minimize patient exposure to empiric therapy with multiple antibiotics. In our experience first-line empirical antibiotic therapy was effective in almost 65% of the cases. Nevertheless, the efficacy of this regimen was unsatisfactory in Gram-negative microorganisms requiring further microbiological and pharmacokinetic evaluation.

The impact of icodextrin on the outcomes of incident peritoneal dialysis patients.

The aim of the study is to investigate the effects of icodextrin on the risks of death, technique failure and the first episode of peritonitis in peritoneal dialysis (PD) patients. From medical records of a medical center in Taiwan, a total of 725 newly diagnosed end-stage kidney disease patients receiving PD for at least 90 days from January 1, 2007 to December 31, 2018 were identified. These patients were grouped as 190 icodextrin users and 535 non-users. Users were defined as utilization of icodextrin for ≥ 50% of their PD duration. The use of icodextrin was considered a time-varying exposure in the Cox proportional hazard model. The risks of death, technique failure and the first episode of peritonitis were compared between two cohorts by the end of 2018. Compared to the non-users, the icodextrin users had significant lower risks of mortality (6.5 vs.7.2 per 100 person-years; adjusted HR = 0.62, 95% CI = 0.42-0.91) and technique failure (12.7 vs. 15.2 per 100 person-years; adjusted HR = 0.61, 95% CI = 0.47-0.81), and the first peritonitis episode (5.0 vs. 17.0 per 100 person-years; adjusted HR = 0.22, 95% CI = 0.14-0.35). The risk of peritonitis reduced further in icodextrin users with diabetes and with cardiovascular disease. Icodextrin was associated with lower risks of mortality, technique failure, and the first episode of peritonitis.

The prognostic values of estimating intraperitoneal pressure in the occurrence of abdominal wall complicationsin peritoneal dialysis patients.

Increased intraperitoneal pressure is associated with abdominal wall complications and technical failure of peritoneal dialysis (PD). Several equations have been developed to estimate intraperitoneal pressure. We aimed to assess the prognostic yield of the intraperitoneal pressure as estimatedby current equations on the occurrence of abdominal wall complications in peritoneal dialysis patients. This is a retrospective analysis of data from a prospective cohortwhich recruited 1207 incident PD patients. Estimated intraperitoneal pressure was calculated using four available equations(according toSigogne, Castellanos, Scanziani and deJesus Ventura). Abdominal wall complications were recorded during follow-up. Univariate analysis and multivariate analysis with competing risk regression were used to assess the predictive power of theestimates of intraperitoneal pressure in the occurrence of abdominal wall complications. During a median follow-up of 30months, 66 (5.5%) patients (1.6/100 patient-years) developed abdominal wall complications. The median time to the occurrence of abdominal wall complications was 5.7months. Only the estimated intraperitoneal pressure by the de Jesus Ventura equation significantly predicted abdominal wall complications by using univariate analyses. Associations between estimated intraperitoneal pressure by the de Jesus Ventura equation and the occurrence of abdominal wall complications disappeared after adjusting for significant clinical factors. We verified the prognostic value of estimation of intraperitoneal pressure by four availableequations in predicting abdominal wall complications in our single-center PD cohort. Due to a low diagnostic yield, a novel equation for estimating the intraperitoneal pressure is urgently needed.

Serum fibroblast growth factor 23 concentration and the risk of mortality in patients undergoing peritoneal dialysis.

Fibroblast growth factor 23 (FGF23) is a phosphate-regulating hormone that is secreted in large amounts early in chronic kidney disease. In this cohort, we aimed to investigate the association between serum FGF23 concentration and mortality in patients undergoing peritoneal dialysis (PD). Serum FGF23 level was determined by enzyme-linked immunosorbent assay (ELISA) in a large 15-year prospective cohort study of PD patients with stored serum samples at baseline. Kaplan-Meier survival curves and Cox proportional hazards models were performed to characterise the relationship of FGF23 with mortality. A total of 737 incident PD patients were analysed. The baseline median FGF23 concentration was 683.2 (518.5-896.2) pg/mL. Age, serum phosphorus, high-density lipoprotein cholesterol and high-sensitivity C-reactive protein were independently correlated with serum FGF23 concentration. During a median follow-up of 66.7 (41.1-95.4) months, 171 of the 737 participants (23.2%) died, including 84 (49.1%) cardiovascular disease-related and 50 (29.2%) infection-related deaths. Multivariable Cox regression analysis showed that the adjusted hazard ratios of the highest tertile of serum FGF23 compared with those in the lowest tertile were 1.36 (95% confidence interval (CI): 0.89-2.07; p = 0.154), 0.75 (95% CI: 0.40-1.38; p = 0.353) and 2.66 (95% CI: 1.15-6.15; p = 0.022) for all-cause, cardiovascular disease-related and infection-related mortality, respectively. High serum FGF23 concentration is associated with a higher risk of infection-related death for incident PD patients.

Gut permeability, circulating bacterial fragments and measures of congestion in peritoneal dialysis.

Limited data exist on the association between gut permeability, circulating bacterial fragment and volume overload in peritoneal dialysis (PD) patients. We measured circulating bacterial fragments, N-terminal pro B-type natriuretic peptide (NT-proBNP), calprotectin and zonulin levels, and evaluate their association with the clinical outcomes in PD patients. This was a single-center prospective study on 108 consecutive incident PD patients. Plasma endotoxin and bacterial DNA, and serum NT-proBNP, calprotectin and zonulin levels were measured. Primary outcomes were technique and patient survival, secondary outcomes were hospitalization data. There was no significant correlation between plasma endotoxin and bacterial DNA, and serum NT-proBNP, calprotectin and zonulin levels. The Homeostatic Model Assessment for Insulin Resistance (HOMA)-2β index, which represents insulin resistance, positively correlated with plasma bacterial DNA (r=0.421, P<.001) and calprotectin levels (r=0.362, P=.003), while serum NT-proBNP level correlated with the severity of volume overload and residual renal function. Serum NT-proBNP level was associated with technique survival even after adjusting for confounding factors [adjusted hazard ratio (aHR) 1.030, 95% confidence interval 1.009-1.051]. NT-proBNP level was also associated with patient survival by univariate analysis, but the association became insignificant after adjusting for confounding factors (aHR 1.010, P=.073). Similarly, NT-proBNP correlated with the number of hospitalizations and duration of hospitalization by univariate analysis, but the association became insignificant after adjusting for confounding factors. There was no correlation between markers of gut permeability, circulating bacterial fragments and measures of congestion in PD patients. Bacterial fragments levels and gut permeability are both associated with insulin resistance. Serum NT-proBNP level is associated with the severity of volume overload and technique survival. Further studies are required to delineate the mechanism of high circulating bacterial fragment levels in PD patients.

Albumin-to-alkaline phosphatase ratio as a novel prognostic indicator in patients undergoing peritoneal dialysis: a propensity score matching analysis.

Though the albumin-to-alkaline phosphatase ratio (AAPR) is used as a biomarker in various diseases, little is known about its effect on outcomes after peritoneal dialysis (PD). This multicenter retrospective study comprised 357 incident PD patients stratified according to the AAPR. Propensity score matching (PSM) was performed to identify 85 patients for a well-matched comparison of all-cause and cardiovascular mortality. Using Cox regression, we performed univariate and multivariate analyses to investigate the prognostic value of the AAPR and established a Kaplan-Meier curve-predicted nomogram to estimate expected overall survival (OS). We assessed the predictive accuracy using the concordance index (c-index). We found that the optimal cut-off of the AAPR to predict mortality was 0.36. In the present cohort of patients undergoing PD, a low AAPR strongly correlated with worse OS. In the multivariate analysis, the AAPR was shown to be an independent marker predicting reduced OS both before [hazard ratio (HR) 1.68, 95% confidence interval (CI) 1.08-2.60, P = 0.020] and after PSM (HR 1.96, 95% CI 1.06-3.62, P = 0.020). We also observed significant differences in OS in several subgroups, but not the group of patients with comorbidities. A nomogram was established to predict overall survival, with a c-index for prediction accuracy was 0.71 after PSM. AAPR has potential as an independent prognostic biomarker in patients undergoing PD.

Atherogenic index predicts all-cause and cardiovascular mortality in incident peritoneal dialysis patients

Background and aimsAtherosclerosis, the main cause of cardiovascular disease (CVD), is prevalent in patients undergoing peritoneal dialysis (PD). Atherogenic index (AI) is a strong predictor of atherosclerosis. However, its prognostic value in CVD outcomes and all-cause mortality among patients undergoing PD remains uncertain. Therefore, we aimed to evaluate the association between AI and all-cause and CVD mortality in PD patients. MethodsCalculated based on lipid profiles obtained through standard laboratory procedures, AI was evaluated in 2682 patients who underwent PD therapy between January 2006 and December 2017 and were followed up until December 2018. The study population was divided into four groups according to the quartile distribution of AI (Q1: <2.20, Q2: 2.20 to <2.97, Q3: 2.97 to <4.04, and Q4: ≥4.04). Multivariable Cox models were employed to explore the associations between AI and CVD and all-cause mortality was evaluated. ResultsDuring a median follow-up of 35.5 months (interquartile range, 20.9–57.2 months), 800 patients died, including 416 deaths from CVD. Restricted cubic splines showed non-linear relationship between AI and adverse clinical outcomes. The risks of all-cause and CVD mortality gradually increased across quartiles (log-rank, p < 0.001). After adjusting for potential confounders, the highest quartile (Q4) showed significantly elevated hazard ratio (HR) for both all-cause mortality (HR 1.54 [95% confidence interval (CI), 1.21–1.96]) and CVD mortality risk (HR 1.78 [95% CI, 1.26–2.52]), compared to the lowest quartile (Q1). ConclusionsAI was independently associated with all-cause and CVD mortality in patients undergoing PD, suggesting that AI might be a useful prognostic marker.