Rate of Decline of Residual Kidney Function Before and After the Start of Peritoneal Dialysis

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

Rationale & Objective

The development of anuria has been 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 starting PD.

Study Design

Retrospective cohort study.

Setting & Participants

Patients who started continuous ambulatory peritoneal dialysis at our center between 2006 and 2020 were included and followed up until January 31, 2023.

Exposure

Age, sex, diabetes, temporary hemodialysis, angiotensin-converting enzyme inhibitors (ACEis) or angiotensin II receptor blockers (ARBs), diuretics, baseline urine volume, serum albumin, daily glucose exposure, peritonitis, and incremental PD.

Outcomes

The primary outcome was early anuria, defined as 24-hour urine volume ≤100 mL within the first year of PD initiation. Secondary outcomes included all-cause mortality, cardiovascular disease mortality, technique failure, and peritonitis.

Analytical Approach

Cox proportional hazards model.

Results

A total of 2,592 patients undergoing continuous ambulatory peritoneal dialysis aged 46.7 ± 14.9 years were recruited. Among them, 58.9% were male, and 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, 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), having 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, whereas 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 ACEis or 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.

Limitations

Single-center and observational study.

Conclusions

Among PD patients at a single center in China, early anuria was relatively uncommon but associated with an increased risk of mortality and PD technique failure. Incremental PD, higher baseline urine output and serum albumin, and lower daily glucose exposure were associated with a lower risk of early anuria. Clinical trials are needed to evaluate the optimal PD techniques to preserve residual kidney function and maximaze outcomes.

Characteristics of patients and facility of peritoneal dialysis in Korea: Results from the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) Korea

BACKGROUND

Varying peritoneal dialysis (PD)-related clinical outcomes have been reported in different countries. As a participant of the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS), this study investigated the characteristics of Korean PD patients, PD facilities and the incidence rates of clinical outcomes including mortality and PD-related outcomes.

METHODS

From July 2019 to December 2021, a total of 766 Korean PD patients were included for analysis. Poisson regression analysis was used to explore the incidence rates of various clinical events including mortality, modality transfer, exit site or catheter tunnel infection and peritonitis.

RESULTS

Among the 766 patients (median age 55.5 years, males 59.5%), 276 were incident and 490 were prevalent PD patients. The incidence rates of events were as follows: all-cause mortality (0.048), modality transfer (0.051), exit site or catheter tunnel infection (0.054) and peritonitis (0.136) events per person year. The most common causative organism for exit site or tunnel infection was staphylococcus species (47%) and that for peritonitis was streptococcus (28%) followed by staphylococcus (27%) species.

CONCLUSIONS

Up to now, PDOPPS Korea has recruited 766 Korean PD patients and started documentation of major PD-related outcomes which occurred during the follow-up period. The overall incidence rates of clinical outcomes in Korean PD patients were relatively favourable. There was no statistically significant difference in the incidence rates of clinical outcomes according to both facility and patient factors.

The relationship between decline rate of residual renal function in the first year and mortality in peritoneal dialysis patients

INTRODUCTION

To assess the relationship between the rate of residual renal function (RRF) decline in the first year and all-cause and cardiovascular mortality in peritoneal dialysis (PD) patients.

METHODS

Incident PD patients were divided into two groups by the corresponding RRF decline value, when hazard ratio (HR) = 1 was found by the restricted cubic spline. The associations of rate of decline of RRF in the first year with mortality were evaluated.

RESULTS

Of 497 PD patients, 122 patients died. After adjusting for confounding factors, patients in fast-decline group had a significant increase risk of all-cause and cardiovascular mortality (HR: 1.97 and 2.09, respectively). Each 0.1-mL/min/1.73 m2 /month decrease in RRF in the first year of PD was associated with a 19% and 20% higher risk of all-cause and cardiovascular mortality, respectively.

CONCLUSIONS

Faster decline of RRF in the first year was independently associated with all-cause and cardiovascular mortality in PD patients.

A Review of Residual Kidney Function in Peritoneal Dialysis Patients

Residual kidney function (RKF) has been associated with better survival, less morbidity, and improved quality of life in peritoneal dialysis (PD) patients. Since higher peritoneal clearance does not lead to better outcomes, more emphasis should be put on preserving kidney function. Many other benefits have been reported, including better volume and blood pressure control, better nutritional status, lower rates of PD peritonitis, preserved erythropoietin and vitamin D production, middle molecule clearance, lower Left Ventricular Hypertrophy, and better serum phosphate level. The most practical method of assessing RKF is the mean of 24-h urinary urea and creatinine clearance. Incremental PD prescription is an ideal option to supplement RKF in PD patients, which also offers more flexibility to the patient and, possibly, improved adherence. Angiotensin converting enzyme inhibitors and angiotensin receptor blockers should be used when possible in PD patients to preserve RKF. Loop diuretics are underutilized in PD patients despite providing an additional means of maintaining fluid balance and reducing the need for higher glucose-containing PD solutions. In this paper, we outline the importance of RKF in PD patients and the different strategies for its preservation.

SGLT2 Inhibitors: The Sweet Success for Kidneys

Sodium-glucose cotransporter-2 inhibitors (SGLT2 inhibitors) were originally developed as antidiabetic agents, with cardiovascular (CV) outcome trials demonstrating improved CV outcomes in patients with type 2 diabetes mellitus (T2D). Secondary analyses of CV outcome trials and later dedicated kidney outcome trials consistently reported improved kidney-related outcomes independent of T2D status and across a range of kidney function and albuminuria. Importantly, SGLT2 inhibitors are generally safe and well tolerated, with clinical trials and real-world analyses demonstrating a decrease in the risk of acute kidney injury. The kidney protective effects of SGLT2 inhibitors generally extend across different members of the class, possibly on the basis of hemodynamic, metabolic, anti-inflammatory, and antifibrotic mechanisms. In this review, we summarize the effects of SGLT2 inhibitors on kidney outcomes in diverse patient populations.

The rationale for the need to study sodium-glucose co-transport 2 inhibitor usage in peritoneal dialysis patients

The wave of kidney and heart outcome trials, showing multiple potential benefits for sodium-glucose co-transport 2 (SGLT2) inhibitors, have excluded patients with an estimated glomerular filtration rate below 25 ml/min/1.73 m2. However, dialysis patients are at the highest risk of cardiovascular disease and would benefit most from effective cardioprotective therapies. There is emerging evidence from experimental studies and post hoc analyses of randomised clinical trials that SGLT2 inhibitors are well tolerated and may also be effective in preventing cardiovascular and mortality outcomes in patients with severe chronic kidney disease, including patients receiving dialysis. As such, extending the usage of SGLT2 inhibitors to dialysis patients could provide a major advancement in their care. Peritoneal dialysis (PD) patients have an additional unmet need for effective pharmacotherapy to preserve their residual kidney function (RKF), with its associated mortality benefits, and for treatment options that help reduce the risk of transfer to haemodialysis. Experimental data suggest that SGLT2 inhibitors, via various mechanisms, may preserve RKF and protect the peritoneal membrane. There is sound physiological rationale and an urgent clinical need to execute robust randomised control trials to study the use of SGLT2 inhibitors in PD patients to answer important questions of relevance to patients and healthcare systems.

Association between lipid profile and residual renal function in incident peritoneal dialysis patients

INTRODUCTION

Residual renal function (RRF) is one of the most crucial factor in the management of peritoneal dialysis (PD). The aim of this study was to evaluate the association between lipid profile and preservation of RRF among incident PD patients.

METHODS

This retrospective cohort study investigated 113 patients (male, 72%; age, 59±14 years) who initiated PD between 2006 and 2017. We investigated the relationships between high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) at PD initiation and change in renal Kt/V during the first year after PD initiation.

RESULTS

Alterations in renal Kt/V during the first year after PD initiation correlated negatively with HDL-C at PD initiation, but not with LDL-C. On multivariate analysis, HDL-C at PD initiation was independently associated with change in renal Kt/V during the first year after PD initiation.

CONCLUSION

These results suggests importance of lipid management among incident PD patients for preservation of RRF.

Residual Renal Function - How Fast Does the Residual Urine Output Function Decline in the First Year of Haemodialysis? - A Scoping Review

Background

Haemodialysis is the most common treatment method in Australia for individuals requiring renal replacement therapy. Although it is known that the residual renal function in these patients has many advantages for their overall health outcomes and that the residual urine volume production is also declining over time, it is unknown how fast this functional decline occurs when patients are embarking on their first year on haemodialysis.

Aim

This scoping review sought to determine if the functional decline in renal residual function in the first year of haemodialysis has been previously investigated, documented or quantified.

Method

The scoping review was performed using variety of nursing and medical databases comprising MEDLINE, Embase, Web of Science and CINAHL Plus with Full Text.

Results

The decline of renal residual function in patients on Peritoneal dialysis over the first year of treatment has previously been described, but not in detail for patients receiving haemodialysis. There is a paucity of knowledge how fast residual urine production can decline in patients receiving haemodialysis during their first year of treatment. A PRISMA checklist has been used to validate the results of this scoping review.

Conclusions

The extended preservation of renal residual function in patients on haemodialysis is crucial for their survival and may have a positive impact on their quality of life. An observational study is needed to examine how fast the functional decrease of the residual urine production function within patients receiving haemodialysis generally occurs. This information could prove to be useful in the context of treatment goals and could inform clinical practice.

Evolving outcomes of peritoneal dialysis: secular trends at a single large center over three decades

Background

Peritoneal dialysis (PD) is improving as a renal replacement therapy for end-stage renal disease (ESRD) patients. We analyzed the main outcomes of PD over the last three decades at a single large-scale PD center with an established high-quality care system.

Methods

As a retrospective cohort study, we included participants (n = 1,203) who began PD between 1990 and 2019. Major PD-related outcomes were compared among the three 10-year cohorts.

Results

The 1,203 participants were 58.3% male with a mean age of 47.9 ± 13.8 years. The median PD treatment duration was 45 months (interquartile range, 19–77 months); 362 patients (30.1%) transferred to hemodialysis, 289 (24.0%) received kidney transplants, and 224 (18.6%) died. Overall, the 5- and 8-year adjust patient survival rates were 64% and 49%, respectively. Common causes of death included infection (n = 55), cardiac (n = 38), and cerebrovascular (n = 17) events. The 5- and 8-year technique survival rates were 77% and 62%, respectively, with common causes of technique failure being infection (42.3%) and solute/water clearance problems (22.7%). The 5-year patient survival significantly improved over time (64% for the 1990–1999 cohort vs. 93% for the 2010–2019 cohort). The peritonitis rate also substantially decreased over time, from 0.278 episodes/patient-year (2000–2004) to 0.162 episodes/patient-year (2015–2019).

Conclusion

PD is an effective treatment option for ESRD patients. There was a substantial improvement in the patient survival and peritonitis rates over time. Establishing adequate infrastructure and an effective system for high-quality PD therapy may be warranted to improve PD outcomes.

Association between different peritoneal dialysis catheter placement methods and short-term postoperative complications

Background

Considering that current peritoneal dialysis has its own shortcomings, In this study, the Seldinger technique was modified to explore the relationship between different catheter placement methods of peritoneal dialysis and short-term postoperative complications.

Methods

We retrospectively analyzed the data of 157 patients who received peritoneal dialysis in the Department of Nephrology of our hospital from January 2017 to December 2019. According to different catheter placement methods, the patients were divided into three groups: 111 cases of open surgery technique, 23 cases of Seldinger technique, and 23 cases of modified Seldinger technique (ultrasound-guided Veress needle puncture). The general data, laboratory indexes, and abdominal infection and catheter-related complications within one month postoperatively were collected.

Results

There were 48 (31.0 %) cases of complications in 157 patients within one month postoperatively, which were mainly catheter-related complications (45 cases, 29.0 %). The incidence of catheter tip peritoneal drift (catheter migration) in the three groups was 27.3 %, 39.1 %, and 9.1 %, respectively, with no significant difference between groups (P = 0.069). Univariate logistic regression analysis showed that the systolic blood pressure, history of abdominal and pelvic surgery, creatinine, and modified Seldinger technique were possible impact factors of catheter migration (P < 0.10). After fully adjusting for confounding factors, Compared with the open surgery group, the modified Seldinger method group significantly reduced the risk of catheter migration with an OR of 0.161 (95 % confidence interval: 0.027–0.961, P = 0.045); However, the difference between the Seldinger method group and the open surgery group was not significant, with an OR of 1.061 (95 % confidence interval: 0.308–3.649, P = 0.926). Curve fitting showed that the average incidence of catheter migration in the three groups was 27.3 % (95% CI: 15.9-42.7 %), 28.5 % (95% CI: 10.7-56.9 %), and 5.7 % (95% CI: 1.0-27.0 %); the modified Seldinger method has the lowest average incidence of catheter migration.

Conclusions

Modified Seldinger technique can significantly reduce catheter-related short-term complications after peritoneal dialysis, and it is especially effective in reducing the incidence of catheter migration. Modified Seldinger technique is a safe and feasible method for the placement of a peritoneal dialysis catheter.

Rate of decline in residual kidney function pre and post peritoneal dialysis initiation: A post hoc analysis of the IDEAL study

Background

Residual kidney function (RKF) is associated with improved survival and quality of life in dialysis patients. Previous studies have suggested that initiation of peritoneal dialysis (PD) may slow RKF decline compared to the pre-dialysis period. We sought to evaluate the association between PD initiation and RKF decline in the Initiating Dialysis Early And Late (IDEAL) trial.

Methods

In this post hoc analysis of the IDEAL randomized controlled trial, PD participants were included if results from 24-hour urine collections had been recorded within 30 days of dialysis initiation, and at least one value pre- and one value post-dialysis commencement were available. The primary outcome was slope of RKF decline, calculated as mean of urinary creatinine and urea clearances. Secondary outcomes included slope of urine volume decline and time from PD initiation to anuria.

Results

The study included 151 participants (79 early start, 72 late start). The slope of RKF decline was slower after PD initiation (-2.69±0.18mL/min/1.73m²/yr) compared to before PD (-4.09±0.33mL/min/1.73m²/yr; change in slope +1.19 mL/min/1.73m²/yr, 95%CI 0.48–1.90, p<0.001). In contrast, urine volume decline was faster after PD commencement (-0.74±0.05 L/yr) compared to beforehand (-0.57±0.06L/yr; change in slope -0.18L/yr, 95%CI -0.34—-0.01, p = 0.04). No differences were observed between the early- and late-start groups with respect to RKF decline, urine volume decline or time to anuria.

Conclusions

Initiation of PD was associated with a slower decline of RKF compared to the pre-dialysis period.

Higher serum phosphorus predicts residual renal function loss in male but not female incident peritoneal dialysis patients

BACKGROUND

Elevated serum phosphorus level is a risk factor for progression of chronic kidney disease in non-dialysis patients. However, the association of serum phosphorus level with residual renal function (RRF) loss among incident continuous ambulatory peritoneal dialysis (CAPD) patients remains unclear.

METHODS

We performed a retrospective analysis of prospectively collected cohort of 1245 incident CAPD patients from January 2006 to December 2015 and followed up until December 2017. Patients were stratified into tertiles according to baseline serum phosphorus levels. RRF loss was defined as residual glomerular filtration rate (mL/min/1.73 m²) reaching zero or estimated urine output less than 200 mL/day on two successive clinic visits. Propensity-score matched Cox's proportional hazards and competing risk models were performed to examine the association of serum phosphorus with RRF loss.

RESULTS

A total of 421 (33.82%) patients had loss of RRF over a median follow-up of 26.23 months. In the entire cohort, elevated serum phosphorus was associated with increased risk for RRF loss after adjustment. In the propensity-score matched cohort, patients in the 3rd tertile of serum phosphorus had a 51% higher risk of RRF loss than those in the combination of the 1st and 2nd tertiles. Furthermore, the association of serum phosphorus level with RRF loss differed by sex (interaction P = 0.018). The adjusted HRs per 1 mg/dL increase in serum phosphorus level of RRF loss were 1.32 (95% CI 1.15-1.50, P < 0.001) for male and 1.03 (95% CI 0.87-1.21, P = 0.750) for female, respectively. These findings persisted in competing risk analysis.

CONCLUSION

Higher serum phosphorus levels independently predicts RRF loss in men treated with CAPD.

Transfers to Hemodialysis Among US Patients Initiating Renal Replacement Therapy With Peritoneal Dialysis

RATIONALE & OBJECTIVE

Identifying patients who are likely to transfer from peritoneal dialysis (PD) to hemodialysis (HD) before transition could improve their subsequent care. This study developed a prediction tool for transition from PD to HD.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults initiating PD between January 2008 and December 2011, followed up through June 2015, for whom data were available in the US Renal Data System (USRDS).

PREDICTORS

Clinical characteristics at PD initiation and peritonitis claims.

OUTCOMES

Transfer to HD, with the competing outcomes of death and kidney transplantation.

ANALYTICAL APPROACH

Outcomes were ascertained from USRDS treatment history files. Subdistribution hazards (competing-risk) models were fit using clinical characteristics at PD initiation. A nomogram was developed to classify patient risk at 1, 2, 3, and 4 years. These data were used to generate quartiles of HD transfer risk; this quartile score was incorporated into a cause-specific hazards model that additionally included a time-dependent variable for peritonitis.

RESULTS

29,573 incident PD patients were followed up for a median of 21.6 (interquartile range, 9.0-42.3) months, during which 41.2% transferred to HD, 25.9% died, 17.1% underwent kidney transplantation, and the rest were followed up to the study end in June 2015. Claims for peritonitis were present in 11,733 (40.2%) patients. The proportion of patients still receiving PD decreased to <50% at 22.6 months and 14.2% at 5 years. Peritonitis was associated with a higher rate of HD transfer (HR, 1.82; 95% CI, 1.76-1.89; P < 0.001), as were higher quartile scores of HD transfer risk (HRs of 1.31 [95% CI, 1.25-1.37), 1.51 [95% CI, 1.45-1.58], and 1.78 [95% CI, 1.71-1.86] for quartiles 2, 3, and 4 compared to quartile 1 [P < 0.001 for all]).

LIMITATIONS

Observational data, reliant on the Medical Evidence Report and Medicare claims.

CONCLUSIONS

A large majority of the patients who initiated renal replacement therapy with PD discontinued this modality within 5 years. Transfer to HD was the most common outcome. Patient characteristics and comorbid diseases influenced the probability of HD transfer, death, and transplantation, as did episodes of peritonitis.

Incremental Peritoneal Dialysis May be Beneficial for Preserving Residual Renal Function Compared to Full-dose Peritoneal Dialysis

Maintaining residual renal function (RRF) is a crucial issue in peritoneal dialysis (PD). Incremental dialysis is the practice of initiating PD exchanges less than four times a day in consideration of RRF, and increasing dialysis dose in a step-wise manner as the RRF decreases. We aimed to compare the outcomes of incremental PD and full-dose PD in terms of RRF preservation and other outcomes. This was a single-center, observational study. Data were extracted retrospectively from a cohort of incident PD patients over 16 years old who started PD between 2007 and 2015 in the PD Unit of Seoul National University Hospital. We used inverse probability weighting (IPW) adjustment based on propensity scores to balance covariates between the incremental and full-dose PD groups. Multivariate, time-dependent Cox analyses were performed. Among 347 incident PD patients, 176 underwent incremental PD and 171 underwent conventional full-dose PD. After IPW adjustment, the incremental PD group exhibited a lower risk of developing anuria (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.43–0.88). Patient survival, technique survival, and peritonitis-free survival were all similar between these groups (P > 0.05 by log-rank test). Incremental PD was beneficial for preserving RRF and showed similar patient survival when compared to conventional full-dose PD.

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.

Rapid Change in Residual Renal Function Decline Is Associated with Lower Survival and Worse Residual Renal Function Preservation in Peritoneal Dialysis Patients

The survival advantage observed among peritoneal dialysis patients early on after dialysis initiation has been largely attributed to residual renal function (RRF) preservation due to higher baseline residual function and fewer comorbidities. We hypothesize that a rapid decline in RRF is associated with higher risk of anuria and mortality. In a retrospective cohort study of 581 subjects on peritoneal dialysis with longitudinal prevalent data, we assessed whether RRF change over time, in addition to baseline RRF, increased risk of mortality and anuria using Kaplan-Meier analysis and Cox proportional hazard analysis to control for known risk factors. Rapid RRF decline (≥ 0.09 decline) over a 12-month period was associated with a 2.6-fold increase in the risk of death (hazard ratio [HR] 2.60, 95% confidence interval [CI] 1.66 - 4.07, compared with < 0.09 decline) and a 2-fold increase in anuria (HR 2.06, 95% CI 1.24 - 3.42). Each quartile of increasing severity of RRF decline over a 12-month period increased risk incrementally for death (2^nd quartile: HR 3.04, CI 1.26 - 7.34; 3^rd quartile: HR 4.01, CI 1.71 - 9.83; 4^th quartile HR 5.78, CI 2.10 - 15.9) and generally for anuria (quartiles with HR 5.72 - 7.21). The escalating risk of mortality and anuria was greater for those with diabetes mellitus. In conclusion, rapid decline in RRF over a 12-month period increased the risk of mortality and likewise anuria, beyond previously established risk factors for mortality and anuria. The impact on mortality and RRF preservation was particularly severe for those with diabetes mellitus.

Decline of kidney function during the pre-dialysis period in chronic kidney disease patients: a systematic review and meta-analysis

Purpose

Substantial heterogeneity exists in reported kidney function decline in pre-dialysis chronic kidney disease (CKD). By design, kidney function decline can be studied in CKD 3–5 cohorts or dialysis-based studies. In the latter, patients are selected based on the fact that they initiated dialysis, possibly leading to an overestimation of the true underlying kidney function decline in the pre-dialysis period. We performed a systematic review and meta-analysis to compare the kidney function decline during pre-dialysis in CKD stage 3–5 patients, in these two different study types.

Patients and methods

We searched PubMed, EMBASE, Web of Science and Cochrane to identify eligible studies reporting an estimated glomerular filtration rate (eGFR) decline (mL/min/1.73 m²) in adult pre-dialysis CKD patients. Random-effects meta-analysis was performed to obtain weighted mean annual eGFR decline.

Results

We included 60 studies (43 CKD 3–5 cohorts and 17 dialysis-based studies). The meta-analysis yielded a weighted annual mean (95% CI) eGFR decline during pre-dialysis of 2.4 (95% CI: 2.2, 2.6) mL/min/1.73 m² in CKD 3–5 cohorts compared to 8.5 (95% CI: 6.8, 10.1) in dialysis-based studies (difference 6.0 [95% CI: 4.8, 7.2]).

Conclusion

To conclude, dialysis-based studies report faster mean annual eGFR decline during pre-dialysis than CKD 3–5 cohorts. Thus, eGFR decline data from CKD 3–5 cohorts should be used to guide clinical decision making in CKD patients and for power calculations in randomized controlled trials with CKD progression during pre-dialysis as the outcome.

Baseline and Time-Averaged Values Predicting Residual Renal Function Decline Rate in Japanese Peritoneal Dialysis Patients

Residual renal function (RRF) is a strong prognostic factor of morbidity and mortality in patients undergoing peritoneal dialysis (PD). We determined predictors of the RRF rate of decline using both baseline values and time-averaged ones. We retrospectively analyzed 94 patients being treated with PD at the Japanese Red Cross Medical Center. The decline rate of RRF was calculated by a diminution in the weekly renal Kt/V between the first and last follow up divided by follow-up years. The mean follow-up period was 2.28 years, and the mean decline rate of weekly renal Kt/V was 0.25 per year. A multivariate analysis using baseline parameters identified dialysis-to-plasma ratios of creatinine at 4 h (P = 0.02), urinary protein (P = 0.02), and mean blood pressure (MBP) (P < 0.01) as being positively associated with the RRF rate of decline, while the use of angiotensin converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) had a negative correlation (P = 0.03). When using time-averaged values as independent variables, a lower weekly total renal Kt/V (P < 0.0001), higher urinary protein (P < 0.0001), and higher MBP (P = 0.04) independently predicted a faster RRF rate of decline. We demonstrated that PD patients with a lower MBP and lower urinary protein both at baseline and throughout their PD duration had a slower RRF rate of decline. We recommend strict control of blood pressure and anti-proteinuric therapy for PD patients.

Predictors of Residual Renal Function Decline in Peritoneal Dialysis Patients: The balANZ Trial

Objective

Preservation of residual renal function (RRF) is associated with improved survival. The aim of the present study was to identify independent predictors of RRF and urine volume (UV) in incident peritoneal dialysis (PD) patients.

Methods

The study included incident PD patients who were balANZ trial participants. The primary and secondary outcomes were RRF and UV, respectively. Both outcomes were analyzed using mixed effects linear regression with demographic data in the first model and PD-related parameters included in a second model.

Results

The study included 161 patients (mean age 57.9 ± 14.1 years, 44% female, 33% diabetic, mean follow-up 19.5 ± 6.6 months). Residual renal function declined from 7.5 ± 2.9 mL/min/1.73 m2 at baseline to 3.3 ± 2.8 mL/min/1.73 m2 at 24 months. Better preservation of RRF was independently predicted by male gender, higher baseline RRF, higher time-varying systolic blood pressure (SBP), biocompatible (neutral pH, low glucose degradation product) PD solution, lower peritoneal ultrafiltration (UF) and lower dialysate glucose exposure. In particular, biocompatible solution resulted in 27% better RRF preservation. Each 1 L/day increase in UF was associated with 8% worse RRF preservation ( p = 0.007) and each 10 g/day increase in dialysate glucose exposure was associated with 4% worse RRF preservation ( p < 0.001). Residual renal function was not independently predicted by body mass index, diabetes mellitus, renin angiotensin system inhibitors, peritoneal solute transport rate, or PD modality. Similar results were observed for UV.

Conclusions

Common modifiable risk factors which were consistently associated with preserved RRF and residual UV were use of biocompatible PD solutions and achievement of higher SBP, lower peritoneal UF, and lower dialysate glucose exposure over time.

Changing Landscape for Peritoneal Dialysis: Optimizing Utilization

The future growth of peritoneal dialysis (PD) will be directly linked to the shift in US healthcare to a value-based payment model due to PD's lower yearly cost, early survival advantage over in-center hemodialysis, and improved quality of life for patients treating their kidney disease in the home. Under this model, nephrology practices will need an increased focus on managing the transition from chronic kidney disease to end-stage renal disease (ESRD), providing patient education with the aim of accomplishing modality selection and access placement ahead of dialysis initiation. Physicians must expand their knowledge base in home therapies and work toward increased technique survival through implementation of specific practice initiatives that highlight PD catheter placement success, preservation of residual renal function, consideration of incremental PD, and competence in urgent start PD. Avoidance of both early and late PD technique failures is also critical to PD program growth. Large dialysis organizations must continue to measure and improve quality metrics for PD, expand their focus beyond the sole provision of PD to holistic patient care, and initiate programs to reduce PD hospitalization rates and encourage physicians to consider the benefits of PD as an initial modality for appropriate patients. New and innovative strategies are needed to address the main reasons for PD technique failure, improve the connectivity of the patient in the home, leverage home biometric data to improve overall outcomes, and develop PD cycler devices that lower patient treatment burden and reduce both treatment fatigue and treatment-dependent complications.