NKF-DOQI clinical practice guidelines for peritoneal dialysis adequacy. National Kidney Foundation

Gut Microbiome Is Related to Cognitive Impairment in Peritoneal Dialysis Patients

Gut microbiota disturbances may influence cognitive function, increasing uremic toxins and inflammation in dialysis patients; therefore, we aimed to evaluate the association of the gut microbiota profile with cognitive impairment (CI) in patients on automated peritoneal dialysis (APD). In a cross-sectional study, cognitive function was evaluated using the Montreal Cognitive Assessment in 39 APD patients and classified as normal cognitive function and CI. The gut microbiota was analyzed using the 16S rRNA gene sequencing approach. All patients had clinical, biochemical and urea clearance evaluations. Eighty-two percent of patients were men, with a mean age of 47 ± 24 years and 11 (7-48) months on PD therapy; 64% had mild CI. Patients with CI were older (53 ± 16 vs. 38 ± 14, p = 0.006) and had a higher frequency of diabetes mellitus (56% vs. 21%, p = 0.04) and constipation (7% vs. 48%, p = 0.04) and lower creatinine concentrations (11.3 ± 3.7 vs. 14.9 ± 5.4, p = 0.02) compared to normal cognitive function patients. Patients with CI showed a preponderance of S24_7, Rikenellaceae, Odoribacteraceae, Odoribacter and Anaerotruncus, while patients without CI had a greater abundance of Dorea, Ruminococcus, Sutterella and Fusobacteria (LDA score (Log10) > 2.5; p < 0.05). After glucose and age adjustment, Odoribacter was still associated with CI. In conclusion, patients with CI had a different gut microbiota characterized by the higher abundance of indole-producing and mucin-fermenting bacteria compared to normal cognitive function patients.

The effect of body mass index on mortality, peritonitis, technique proficiency and residual renal function in peritoneal dialysis patients

BACKGROUND

The prevalence of obesity is increasing worldwide. Obesity is also increasing in the chronic kidney disease (CKD) population. There are conflicting data on complications such as mortality, peritonitis, and technique proficiency of peritoneal dialysis (PD) in underweight and obese patients according to body mass index (BMI). We aimed to present the data in our region to the literature by comparing the residual renal function (RRF), peritonitis, technique proficiency, and mortality rates of the patients we grouped according to BMI.

METHODS

The data of 404 patients who were started and followed up in our clinic between March 2005 and November 2021 were evaluated retrospectively. They were grouped as underweight, normal weight, overweight, and obese according to BMI. RRF, mortality, technique proficiency and peritonitis data of the groups were compared.

RESULTS

Of the 404 patients, 44 were underweight, 199 were normal weight, 110 were overweight, and 55 were obese. No difference was found between the groups in the technique survey and in the time to first peritonitis with Kaplan-Meier analysis (respectively; p = 0.610, p = 0.445). Multivariate Cox regression analysis showed that BMI did not affect mortality (HR 1.196 [95% CI 0.722-1.981] (p = 0.488)).

CONCLUSION

In conclusion, we report that BMI has no effect on RRF, peritonitis, technique proficiency, and mortality in patients undergoing PD, and that mortality may depend on additional factors such as mean albumin, time to first peritonitis, and loss of RRF.

Apparent Treatment-Resistant Hypertension in the First Year Associated With Cardiovascular Mortality in Peritoneal Dialysis Patients

BACKGROUND

Few reports have focused on the association between apparent treatment-resistant hypertension (aTRH) and cardiovascular (CV) mortality in peritoneal dialysis (PD) population, thus we conducted this retrospective cohort to explore it.

METHODS

This was a retrospective cohort study conducted from January 2011 to January 2020 with PD patients in 4 Chinese dialysis centers. aTRH was defined according to the American College of Cardiology and American Heart Association guidelines. aTRH duration was calculated as the total number of months when patients met the diagnostic criteria in the first PD year. The primary outcome was CV mortality, and the secondary outcomes were CV events, all-cause mortality, combined endpoint (all-cause mortality and transferred to hemodialysis [HD]), and PD withdrawal (all-cause mortality, transferred to HD, and kidney transplantation). Cox proportional hazards models were used to assess the association.

RESULTS

A total of 1,422 patients were finally included in the analysis. During a median follow-up period of 26 months, 83 (5.8%) PD patients incurred CV mortality. The prevalence of aTRH was 24.1%, 19.9%, and 24.6% at 0, 3, and 12 months after PD initiation, respectively. Overall, aTRH duration in the first PD year positively associated with CV mortality (per 3 months increment, adjusted hazards ratio [HR], 1.29; 95% confidence interval 1.10, 1.53; P = 0.002). After categorized, those with aTRH duration more than 6 months presented the highest adjusted HR of 2.92. Similar results were found for secondary outcomes, except for the CV event.

CONCLUSIONS

Longer aTRH duration in the first PD year is associated with higher CV mortality and worse long-term clinical outcomes. Larger studies are warranted to confirm these findings.

CLINICAL TRIALS REGISTRATION

There is no clinical trial registration for this retrospective study.

Effects of incremental peritoneal dialysis with low glucose-degradation product neutral pH solution on clinical outcomes

PURPOSE

Incremental peritoneal dialysis (IPD) could decrease unfavorable glucose exposure results and preserve (RKF). However, there is no standardization of dialysis prescriptions for patients undergoing IPD. We designed a prospective observational multi-center study with a standardized IPD prescription to evaluate the effect of IPD on RKF, metabolic alterations, blood pressure control, and adverse outcomes.

METHODS

All patients used low GDP product (GDP) neutral pH solutions in both the incremental continuous ambulatory peritoneal dialysis (ICAPD) group and the retrospective standard PD (sPD) group. IPD patients started treatment with three daily exchanges five days a week. Control-group patients performed four changes per day, seven days a week.

RESULTS

A total of 94 patients (47 IPD and 47 sPD) were included in this study. The small-solute clearance and mean blood pressures were similar between both groups during follow-up. The weekly mean glucose exposure was significantly higher in sPD group than IPD during the follow-up (p < 0.001). The patients with sPD required more phosphate-binding medications compared to the IPD group (p = 0.05). The rates of peritonitis, tunnel infection, and hospitalization frequencies were similar between groups. Patients in the sPD group experienced more episodes of hypervolemia compared to the IPD group (p = 0.007). The slope in RKF in the 6th month was significantly higher in the sPD group compared to the IPD group (65% vs. 95%, p = 0.001).

CONCLUSION

IPD could be a rational dialysis method and provide non-inferior dialysis adequacy compared to full-dose PD. This regimen may contribute to preserving RKF for a longer period.

Incremental dialysis: review of the literature with pediatric perspective

Drivers towards initiation of kidney replacement therapy in advanced chronic kidney disease include metabolic and fluid derangements, growth, and nutritional status with focus on health optimization. Once initiated, prescription of dialysis is often uniform despite variability in patient characteristics and etiology of kidney failure. Preservation of residual kidney function has been associated with improved outcomes in patients with advanced chronic kidney disease on dialysis. Incremental dialysis is the approach of reducing the dialysis dose by reduction in treatment time, days, or efficiency of clearance. Incremental dialysis has been described in adults at initiation of kidney replacement therapy, to better preserve residual kidney function and meet the individual needs of the patient. Consideration of incremental dialysis in pediatrics may be reasonable in a subset of children with continued emphasis on promotion of growth and development.

The Removal of Uremic Solutes by Peritoneal Dialysis

ABSTRACT

Peritoneal dialysis (PD) is now commonly prescribed to achieve target clearances for urea or creatinine. The International Society for Peritoneal Dialysis has proposed however that such targets should no longer be imposed. The Society's new guidelines suggest rather that the PD prescription should be adjusted to achieve well-being in individual patients. The relaxation of treatment targets could allow increased use of PD. Measurement of solute levels in patients receiving dialysis individualized to relieve uremic symptoms could also help us identify the solutes responsible for those symptoms and then devise new means to limit their accumulation. This possibility has prompted us to review the extent to which different uremic solutes are removed by PD.

Hypokalemia Duration in the First Year Associated with Subsequent Peritoneal Dialysis-Associated Peritonitis: A Multicenter Retrospective Cohort Study

BACKGROUND

The association of hypokalemia (LK) with peritoneal dialysis-associated peritonitis (PDAP) risk remains uncertain. Here, we calculated LK duration in the first PD year and evaluated its association with PDAP.

METHODS

A multicenter, retrospective, incident cohort study of 1633 participants was conducted from January 2008 to October 2020 in China. The duration of LK and severe hypokalemia (SLK) was calculated as the total number of months that a patient's serum potassium (SK) level was less than 3.5 or 3.0 mEq/L during the first PD year. The study outcome was the risk of subsequent PDAP started in the second year and later. Cox proportional hazards models and competing risk models were used to assess the association.

RESULTS

The subsequent PDAP occurred in 420 (25.7%) participants during a median of 28 months of follow-up. Overall, LK duration in the first year was positively associated with a subsequent PDAP risk (per 3-month increments, adjusted HR, 1.13; 95%CI: 1.05-1.23). After categorization, patients with LK duration longer than 6 months had the highest adjusted HR of 1.53 (p = 0.005 vs. those without LK) for subsequent PDAP risk. A similar trend was also found for SLK duration. In a competing risk model, a similar trend was also observed. None of the variables, including demographic and PD characteristics, diabetes history, and several clinical measurements, significantly modified this association. The causative organisms of PDAP were similar to those previously reported.

CONCLUSIONS

PD patients with longer LK duration in the first year had a higher subsequent PDAP risk.

Peritoneal dialysis adequacy: a paradigm shift

For the past 30 years, nephrologists have focused on a single minimal threshold of Kt/V_urea to determine the adequacy of peritoneal dialysis (PD). To date, there is no evidence that shows Kt/V_urea to be a good surrogate measure of uremic symptom control or nutritional state in patients on PD. Volume of distribution (V_urea) generally is considered equivalent to total body water (TBW). Yet, accurate determination of TBW is difficult. The most recent International Society for Peritoneal Dialysis practice recommendations on prescribing high-quality PD emphasized incorporation of multiple measures rather than the single value of Kt/V_urea. These measures include shared decision-making between the patient and the care team and assessment of health-related quality of life, burden of uremic symptoms, presence of residual kidney function, volume status, and biochemical measures including serum potassium and bicarbonate levels. In some cases, PD prescriptions can be tailored to the patient priorities and goals of care, such as in frail and pediatric patients. Overall, there has been a paradigm shift in providing high-quality care to PD patients. Instead of focusing on small solute clearance in the form of Kt/V_urea, nephrologists are encouraged to use a more comprehensive assessment of the patient as a whole.

Current apparent treatment-resistant hypertension in patients undergoing peritoneal dialysis: A multi-center cross-sectional study

Apparent treatment‐resistant hypertension (aTRH) is the most commonly used term to report resistant hypertension (RH) and is considered as a common problem in dialysis population. However, few reports have focused on peritoneal dialysis (PD) hypertensive patients. The authors conducted a multi‐center cross‐sectional study involving 1789 PD patients from nine centers in Guangdong, China. The prevalence of aTRH was estimated by home blood pressure (BP) monitoring. Evaluating drug adherence through Eight‐item Morisky Medication Adherence Scale (MMAS‐8) and pill counting was performed to assess RH in one PD center. Related factors of aTRH were analyzed using logistic regression analysis. The prevalence of aTRH in PD patients was estimated at 42.2% (755 out of 1789 hypertensive patients) based on home BP. Of those, 91.4% patients were classified as uncontrolled RH, 2.0% as controlled RH, and 6.6% as refractory hypertension. The prevalence of RH was 40.6% and 41.9% among those with medium/high adherence based on the MMAS‐8 scores and the pill counting rate, respectively. PD patients who were younger, with higher body mass index, with lower serum albumin and poorer dialysis adequacy were significantly associated with higher aTRH incident. In conclusion, the present study demonstrates a high prevalence of aTRH in PD population, which occurs in about two in five treated hypertensive patients. Nutritional status and dialysis adequacy might tightly associate with aTRH.

Patient Selection and Planning for Image-Guided Peritoneal Dialysis Catheter Placement

Image-guided percutaneous peritoneal dialysis (PD) catheter insertion has become increasingly relied upon to provide urgent access for late presenting kidney failure patients, to overcome surgical backlogs and limited operating room access, to avoid general anesthesia in high-risk patients, and, by itself, as an alternative approach to surgical PD access. Advanced planning for the procedure is essential to assure the best possible outcome. Appropriate selection of patients for percutaneous PD catheter placement, choosing the most suitable catheter type, determining insertion and exit site locations, and final patient preparations facilitate the performance of the procedure, minimizes the risk of complications, and improves the likelihood of providing a successful long-term peritoneal access.

Incremental peritoneal dialysis is a safe and feasible prescription in incident patients with preserved residual kidney function

BACKGROUND

Incremental peritoneal dialysis (PD) is recommended as a component of high-quality care by the international society for PD; however, its feasibility and clinical outcomes have not been widely reported. The aim of this study is to describe our experience with incremental PD.

METHODS

This was a retrospective cohort study of incident PD patients at Eastern Health between 2015 and 2019. Patients who stopped PD within 30 days were excluded. Incremental PD was defined in CAPD as using <8 L/day of exchange volume and in automated PD as dialysing without a last fill. Dialysis modality accorded with patient and physician preferences.

RESULTS

The 96 patients were included in this study; 54 with incremental PD. Compared to full-dose PD, incremental PD patients were more likely to be female, had less comorbid diabetes (28% vs. 52%) and higher residual kidney function (RKF) (Kt/V 2.0 ± 0.7 vs. 1.4 ± 0.7). Age, BMI and starting eGFR did not differ between groups. Incremental PD exposed patients to lower exchange volumes (4.4 ± 2.1 vs. 8.5 ± 1.1 L/day), glucose load (46 ± 41 g/day vs. 119 ± 46) and was associated with a longer peritonitis-free survival. PD technique survival, rates of peritonitis or hospitalization were comparable between groups. Predictors for longer incremental PD use included older age and higher starting eGFR.

CONCLUSIONS

Incremental PD is a feasible, goal-directed initial prescription in patients with RKF with comparable peritonitis rates and technique survival. Validation of this prescription in prospective studies is warranted.

Ulnar-Basilic Arteriovenous Fistula for Hemodialysis Access: Utility as the "Second Procedure" after Radio Cephalic Fistula

Objectives: As per standard guidelines, the recommended order of arteriovenous fistula (AVF) creation for hemodialysis (HD) access is radiocephalic (RC), followed by proximal elbow fistulas and arteriovenous graft. Although ulnar-basilic (UB) fistula has been an alternative to RC-AVF, still this procedure searches clear recommendations. We present here our experience on UB-AVF as the preferred “second procedure” instead of proximal fistula after the RC-AVF.

Methods: Forty-two UB-AVF were created in nonfeasible and failed RC-AVF cases between 2016 and 2018. They were reviewed retrospectively and outcomes were compared with 480 RC-AVF constructed within the same period.

Results: The primary patency at 18 months was 73.8%, 69.6% and mean maturation time was 33.7±6.6 days, 32.1±4.7 days for UB-AVF and RC-AVF respectively (p>0.05).

Conclusion: Our altered order of preference enabled us to create all the first-time fistula in the distal forearm, providing all the advantages of distal fistula like RC-AVF and avoiding proximal fistula, improved patient convenience and short-term benefit. In an inference that may be used for references and needs support from a larger sample and longer duration study from other centers, UB-AVF may be considered as the second option after RC-AVF depending on the clinical scenario.

Lowering dialysis sessions duration may be dangerous

Dialysis session in less duration - either to give a better quality of life for the patient or to optimize the organization the dialysis institution - may have bad repercussions on the quality of the treatment and therefore the quality of life of the patient. According to the result of the publications listed in this work, we conclude that it is necessary to perform either longer sessions or more frequent treatments to limit the interval time between two sessions. As this is difficult to perform by the providers, we recommend to develop home dialysis to obtain the best result.

Implication of Trends in Timing of Dialysis Initiation for Incidence of End-stage Kidney Disease

IMPORTANCE

In the last 2 decades, there have been notable changes in the level of estimated glomerular filtration rate (eGFR) at which patients initiate long-term dialysis in the US and around the world. How changes over time in the likelihood of dialysis initiation at any given eGFR level in at-risk patients are associated with the population burden of end-stage kidney disease (ESKD) has not been not well defined.

OBJECTIVE

To examine temporal trends in long-term dialysis initiation by level of eGFR and to quantify how these patterns are associated with the number of patients with ESKD.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study analyzing data obtained from a large, integrated health care delivery system in Northern California from 2001 to 2018 in successive 3-year intervals. Included individuals, ranging in number from as few as 983 122 (2001-2003) to as many as 1 844 317 (2016-2018), were adult members with 1 or more outpatient serum creatinine levels determined in the prior year.

MAIN OUTCOMES AND MEASURES

One-year risk of initiating long-term dialysis stratified by eGFR levels. Multivariable logistic regression was performed to assess temporal trends in each 3-year cohort with adjustment for age, sex, race, and diabetes status. The potential change in dialysis initiation in the final cohort (2016-2018) was estimated using the relative difference between the standardized risks in the initial cohort (2001-2003) and the final cohort.

RESULTS

In the initial 3-year cohort, the mean (SD) age was 55.4 (16.3) years, 55.0% were women, and the prevalence of diabetes was 14.9%. These characteristics, as well as the distribution of index eGFR, were stable across the study period. The likelihood of receiving dialysis at eGFR levels of 10 to 24 mL/min/1.73 m2 generally increased over time. For example, the 1-year odds of initiating dialysis increased for every 3-year interval by 5.2% (adjusted odds ratio, 1.052; 95% CI, 1.004-1.102) among adults with an index eGFR of 20 to 24 mL/min/1.73 m2, by 6.6% (adjusted odds ratio, 1.066; 95% CI, 1.007-1.130) among adults with an eGFR of 16 to 17 mL/min/1.73 m2, and by 5.3% (adjusted odds ratio, 1.053; 95% CI, 1.008-1.100) among adults with an eGFR of 10 to 13 mL/min/1.73 m2, adjusting for age, sex, race, and diabetes. The incidence of new cases of ESKD was estimated to have potentially been 16% (95% CI, 13%-18%) lower if there were no changes in system-level practice patterns or other factors besides timing of initiating long-term dialysis from the initial 3-year interval (2001-2003) to the final interval (2016-2018) assessed in this study.

CONCLUSIONS AND RELEVANCE

The present results underscore the importance the timing of initiating long-term dialysis has on the size of the population of individuals with ESKD.

Duration of Serum Phosphorus Control Associated with Overall Mortality in Patients Undergoing Peritoneal Dialysis

BACKGROUND

Serum phosphorus (SP) level is closely associated with overall mortality and cardiovascular events, while the role of SP controlled duration is not fully recognized. Here, we conducted a retrospective cohort study in our department to identify the relationship of SP controlled duration with clinical outcomes in patients undergoing peritoneal dialysis (PD).

METHODS

PD patients in our center from January 1, 2009, to June 30, 2019, were followed up at 2-month (the first year) or 5-month (the next follow-up period) intervals, and until death, until PD withdrawal, or until June 30, 2019. Data at each follow-up point were collected from their medical records. SP levels, changed degree of SP over baseline, and SP controlled duration were analyzed with overall mortality, PD withdrawal (including death, transferred to hemodialysis, and received renal transplantation), and combined endpoint (including death, acute heart failure, cardiovascular event, and stroke).

RESULTS

A total of 530 patients entered the analysis. Of them, 456 (86.0%) had hyperphosphatemia before dialysis, and the SP levels decreased soon after dialysis. The degree of SP change over baseline was the maximum at the 3rd month after dialysis (-31.0%), and lower degree was associated with higher overall mortality (hazard ratio [HR], 1.012; 95% CI, 1.004-1.020; p = 0.003). The median SP controlled duration was 13 (5-28) months, and longer duration was significantly associated with lower overall mortality (HR, 0.968; 95% CI, 0.956-0.981; p < 0.001). After categorization, duration more than 12 months greatly improved overall mortality with a HR of 0.197 (0.082-0.458; p < 0.001 vs. SP never controlled group) and 0.329 (0.150-0.724; p = 0.006 vs. duration <12 months group). Longer SP controlled duration also improved PD withdrawal and combined endpoint.

CONCLUSIONS

In summary, both degree and duration of SP control were tightly associated with overall mortality. We should control SP levels as early, as possible, and as long as we could.

Radial artery diameterand and age related functional maturation of the radio-cephalic arteriovenous fistula

Background

Previous studies have not described the relationship between reducing radial artery diameter as well as increasing age and functional maturation of the radio-cephalic arteriovenous fistula (RCAVF) and no data identify these as linear relationship. The objective of this study was to perform trend analysis to assess these aspects.

Methods

Our retrospective cohort study enrolled and analyzed 353 follow-up cases that underwent first AVF creation. The artery and vein sizes were measured by ultrasound. We performed follow-up, a minimum of 3 months after surgery. Multivariable logistic regression analysis was used to identify independent risk factors inmaturation. Participant age was categorized into four groups (age ≤ 29, 30–49, 50–69, and 70–90 years). Radial artery diameter was categorized into four groups (≤ 1.9, >1.9 and ≤ 2.1, >2.1 and ≤ 2.4, >2.4 mm) according to median and interquartile ranges. We adjusted for confounders in four logistic models, and primary analyses were based on building ordered category models and tested P values for trends to estimate the relationship of radial artery diameter and each 20-year increase in age with risk of maturation.

Results

The mature RCAVF group included 301 cases, and the immature group included 52 cases. Radial artery diameter, age, and diabetes were independent risk factors of maturation. Odds ratios (ORs) associated with maturation reduced with increasing age, while ORs increased with increasing radial artery diameter. P values for trends(<0.05) were observed in all four models. A reduction in radial artery diameter and higher age were significantly associated with a higher incidence of immaturity after adjusting the multivariate models. The risks of immaturation were increased by more than 1.54 fold for each 20-year increase and increased by more than 1.34 fold for the smaller radial artery diameter group.

Conclusion

Our findings suggest that a significantly higher immaturity risk of RCAVF was associated with increasing age and a reduction in radial artery diameter. Our study identified a linear exposure-response relationship of age and radial artery diameter with immaturity incident. A careful selection of patients will be helpful in improving AVF functional maturation.

Effects of educational practices on the peritonitis risk in peritoneal dialysis: a retrospective cohort study with data from the French peritoneal Dialysis registry (RDPLF)

Background

Peritoneal dialysis (PD) is a home-based therapy performed by patients or their relatives in numerous cases, and the role of patients’ educational practices in the risk of peritonitis is not well assessed. Our aim was to evaluate the effect of PD learning methods on the risk of peritonitis.

Methods

This was a retrospective multicentric study based on data from a French registry. All incident adults assisted by family or autonomous for PD exchanges in France between 2012 and 2015 were included. The event of interest was the occurrence of peritonitis. Cox and hurdle regression models were used for statistical analysis to asses for the survival free of peritonitis, and the risk of first and subsequent peritonitis.

Results

1035 patients were included. 967 (93%) received education from a specialized nurse. Written support was used for the PD learning in 907 (87%) patients, audio support in 221 (21%) patients, and an evaluation grid was used to assess the comprehension in 625 (60%) patients. In the “zero” part of the hurdle model, the use of a written support and starting PD learning with hands-on training alone were associated with a lower survival free of peritonitis (respectively HR 1.59, 95%CI 1.01–2.5 and HR 1.94, 95%CI 1.08–3.49), whereas in the “count” part, the use of an audio support and starting of PD learning with hands-on training in combination with theory were associated with a lower risk of presenting further episodes of peritonitis after a first episode (respectively HR 0.55, 95%CI 0.31–0.98 and HR 0.57, 95%CI 0.33–0.96).

Conclusions

The various PD education modalities were associated with differences in the risk of peritonitis. Prospective randomized trials are necessary to confirm causal effect. Caregivers should assess the patient’s preferred learning style and their literacy level and adjust the PD learning method to each individual.

Characterization of sodium removal to ultrafiltration volume in a peritoneal dialysis outpatient cohort

Background

Failure to control volume is the second most common cause of peritoneal dialysis (PD) technique failure. Sodium is primarily removed by convection, but according to the three-pore model, water and sodium movements are not necessarily concordant. We wished to determine factors increasing sodium to water clearance in clinical practice.

Methods

We reviewed 24-h peritoneal dialytic sodium removal (DSR) and ultrafiltration (UF) volume in consecutive PD patients attending for routine assessment of peritoneal membrane function and adequacy testing. We used a regression model with the DSR/UF ratio as the dependent variable. A second model with DSR as the dependent variable and interaction testing for UF was used as sensitivity analysis.

Results

We included 718 adult PD patients. Mean values were 51.8 ± 64.6 mmol/day and 512 ± 517 mL/day for DSR and UF, respectively. In multivariable analysis, DSR/UF ratio was positively associated with transport type (fast versus slow, P < 0.001), serum sodium (P < 0.001) and diabetes (P = 0.026), and negatively associated with PD mode [automated PD versus continuous ambulatory PD (CAPD), P < 0.001] and the use of 2.27% glucose dialysate (P < 0.001). Sensitivity analysis showed positive interaction with UF for transport type (P < 0.001) and serum sodium (P = 0.032) and negative interaction for PD mode (P < 0.001) and cycles number (P < 0.001).

Conclusions

CAPD, fast transport and high serum sodium allow relatively more sodium to be removed compared with water. Icodextrin has no effect on sodium removal once confounders have been accounted for. Although widely used in the assessment of PD patients, UF should not be considered as a surrogate for DSR in clinical practice.

Flexibility in peritoneal dialysis prescription: Impact on technique survival

Background:

Patient burnout is a major cause of technique failure on peritoneal dialysis (PD). Reducing the PD prescription on an individual basis, dependent upon residual kidney function (RKF), may have a role in prolonging time on PD by reducing dialysis burden. This retrospective study aimed to determine the safety and impact of flexible PD prescribing on technique and patient survival.

Methods:

All patients (186) from our centre starting PD from 1st January 2012 to 31st December 2016 were included. Data on dialysis prescription were collected for each patient from the time they had started PD, and dialysis adequacy measured regularly (3–6 monthly) using PD Adequest.

Results:

Median age at start of dialysis was 61 years. Only 49% started on PD 7 days a week and this dropped to 27% at 3 months following the first clearance test. Over 90% achieved creatinine clearance > 50 L/week/1.73 m2 up to 2 years of follow-up, with 87% achieving this standard at 3 years. Patient and technique survival at 1, 2 and 3 years were 91%, 81%, and 72%, and 89%, 87% and 78% respectively. Factors on univariate analysis affecting technique survival included increasing age (HR 0.98, p = 0.04, 95% CI (0.96–0.999)), two or more episodes of PD-associated peritonitis (HR 4.52, p = 0.00, 95% CI (1.87–10.91)) and increasing PD intensity (HR 3.30, p = 0.02, 95% CI (1.22–8.93)). After multivariate adjustment which included baseline kidney function, low PD intensity continued to be associated with better technique survival (HR 0.17, p = 0.03, 95% CI (0.03–0.85)).

Conclusion:

Tailoring the PD prescription to RKF enables days off dialysis while still maintaining recommended levels of small solute clearance. This approach reduces dialysis burden and is associated with higher technique survival.

Optimization of Peritoneal Dialysis Prescription Using Computer Models of Peritoneal Transport

Computer models are valuable clinical tools in the effort to improve quality of life for dialysis patients. At present, two software programs have been validated clinically in adult and pediatric populations. They are the Personal Dialysis Capacity (PDC: Gambro Lundia AB, Lund, Sweden) and PD Adequest (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.). Both programs seem to give accurate predictions of small-solute clearance, but the PDC seems to be superior in predicting ultrafiltration volumes. Indeed, the software programs have several important differences that affect their accuracy and, hence, their clinical value. The PDC software introduces the concepts of capillary physiology to the field of peritoneal dialysis. It gives a functional description of the peritoneal membrane of the individual patient. Recently, its “new” area parameter (A0/Δx) was shown to be superior to the peritoneal equilibration test (PET) in predicting transperitoneal exchange.

The Initiating Dialysis Early and Late (Ideal) Study: Study Rationale and Design

Objectives

The primary objective of the IDEAL study is to determine whether the timing of dialysis initiation has an effect on survival in subjects with end-stage renal disease (ESRD). The secondary objectives are to determine the impact of “early start” versus “late start” dialysis on nutritional and cardiac morbidity, quality of life, and economic cost.

Design

Prospective multicenter randomized controlled trial. Patients are randomized to commence dialysis at a glomerular filtration rate (by Cockcroft–Gault) of either 10 – 14 mL/minute/1.73 m2 (“early start”) or 5 – 7 mL/min/1.73 m2 (“late start”), with stratification for dialysis modality (hemodialysis vs peritoneal dialysis), study center, and the presence or not of diabetes mellitus.

Setting

Dialysis units throughout Australia and New Zealand.

Patients

Patients with ESRD commencing chronic dialysis therapy.

Outcome Measures

Three years from randomization, all-cause mortality, morbidity, and economic impact; structural and functional cardiac status, nutritional state, and quality of life will be assessed.

Results

To date, 388 patients of a minimum 800 patients have been entered and randomized into the study. Current recruitment rates suggest sufficient patients will be enrolled by December 2004 and follow-up completed by December 2007.

Conclusions

The IDEAL study will provide evidence for the optimal time to commence dialysis.

A Novel Objective Nutritional Score for Children on Chronic Peritoneal Dialysis

Objectives

To establish a novel nutritional score based on a series of objective parameters capable of detecting protein-calorie malnutrition in children being treated with chronic peritoneal dialysis (CPD), to test the score in a healthy pediatric population, and to apply it to children on CPD to evaluate their nutritional status.

Study Population

264 healthy school children (mean age 8.69 ± 3.26 years, range 3.05 – 14.98 years) and 29 patients treated with CPD for 1.75 ± 1.02 years (mean age 10.54 ± 6.28 years, range 2.8 – 15.24 years).

Methods

Nutritional status was evaluated by means of three sets of measurements: anthropometric (A1 and A2) and bioimpedance analysis (BIA) measurements. Anthropometry included two sets of measures: set A1 consisted of height (H), weight (W), and body mass index (BMI); set A2 consisted of midarm muscle circumference (MAMC), arm muscle area (AMA), and arm fat area (AFA). The BIA measurements included reactance, phase angle, and distance. All parameters are expressed as standard deviation scores (SDS). Tanner's, Rolland–Cachera's, and Frisancho's data were used as references for H, W, BMI, MAMC, AMA, and AFA; personal data obtained from 551 healthy boys and girls were used for the BIA indices. The nine anthropometry and BIA parameters were given scores of 1 to 5: 5 = > 0 SDS, 4 = ≤ 0 and > –1 SDS, 3 = ≤ –1 and > –2 SDS, 2 = ≤ –2 and > –3 SDS, and 1 = ≤ –3 SDS. Average scores were established for each of A1, A2, and BIA, and then summed to obtain the anthropometry–BIA nutrition (ABN) score. To establish the cutoff value between normal nutritional status and malnutrition, the method was first applied to the 264 healthy children; distribution percentiles were calculated for each area score and the ABN score. The ABN score corresponding to the 3rd percentile was considered the limit of normality and then applied three times to the 29 children on CPD, for a total of 87 nutritional assessments.

Results

The score corresponding to the 3rd percentile in the population of healthy children was 10.33. Among the CPD-treated children, 41.4% of the ABN scores were higher than 10.33 (indicating a state of normal nutrition) and 58.6% were lower (indicating various degrees of malnutrition). Severe malnutrition was found in only 1.1% of the cases. The values of all nine A1, A2, and BIA parameters, as well as serum albumin levels, were significantly higher in patients with an ABN score > 10.33 than in those with a score < 10.33.

Conclusion

The ABN score is a simple and objective method of assessing, in clinical practice, the nutritional status of children on CPD.

Evaluation of Nutritional Status and Factors Related to Malnutrition in Children on CAPD

Objective

The aim of this study was to investigate the nutritional status of children on continuous ambulatory peritoneal dialysis (CAPD) and to relate it to the dose of dialysis and serum levels of inflammatory cytokines and insulin-like growth factor-1 (IGF-1).

Patients

17 CAPD patients (8 girls, 9 boys; mean age 13.1 ± 3.5 years, median 15 years) were included in the study. Anthropometric measurements and serum albumin levels were used in the evaluation of nutritional status. Serum interleukin (IL)-1β, IL-6, tumor necrosis factor α, and IGF-1 levels were determined in all CAPD patients and in a healthy control group. Weekly Kt/V and creatinine clearance (CCr) were measured to determine adequacy of dialysis.

Results

The mean dialysis period was 23.7 ± 15.2 months (median 23 months). Anthropometric measurements and serum albumin level were as follows: height 130.2 ± 15.6 cm, height standard deviation score (HtSDS) -4.2 ± 2.4, body mass index (BMI) 16.3 ± 1.6 kg/m2, body mass index standard deviation score (BMISDS) -0.8 ± 0.9, triceps skinfold thickness (TST) 4.2 ± 1.4 mm, midarm circumference (MAC) 16.21 ± 2.3 cm, upper arm muscle area (AMA) 1799.1 ± 535.7 mm2, upper arm fat area (AFA) 334.5 ± 143 mm2, and serum albumin 3.1 ± 0.7 g/dL. The BMI was above the fifth percentile in all patients; TST and MAC were below the fifth percentile in 14 patients (82.4%) and 10 patients (58.8%) respectively. The AMA was below the fifth percentile in 8 patients; however, the AFA was below the fifth percentile in all patients. Mean serum albumin level was under 3.5 g/dL in 70.5% of the children. We found significant positive correlations between BMI and Kt/V ( r = 0.69, p < 0.01), CCr ( r = 0.64, p < 0.05), and IL-6 ( r = 0.61, p < 0.01). There was an inverse correlation between BMISDS and dialysis period ( r = -0.58, p < 0.05); and between IL-6 and serum albumin ( r = -0.49, p < 0.05). A significant positive correlation between BMISDS and serum IGF-1 level ( r = 0.62, p < 0.01) was noted. We also found a significant positive correlation between serum IGF-1 level and both HtSDS ( r = 0.57, p < 0.05) and TST ( r = 0.52, p < 0.05). Significant positive correlations between AFA and CCr and IGF-1 were also noted (both r = 0.56, p < 0.05).

Conclusion

Although many factors may be responsible for malnutrition and growth retardation, we found that prolonged period of dialysis, inadequate dialysis, and low IGF-1 levels are the most important risk factors in CAPD patients.

Attitudes of Canadian Nephrologists toward Dialysis Modality Selection

Objective

To determine the opinions and attitudes of Canadian nephrologists about dialysis modality decisions and optimal dialysis system design.

Participants

Members of the Canadian Society of Nephrology.

Intervention

A mailed survey questionnaire.

Results

A 66% response rate was obtained. Decisions about modality are reported to be based most strongly on patient preference (4.4 on a scale from 1 to 5), followed by quality of life (4.06), morbidity (3.97), mortality (3.85), and rehabilitation (3.69), while neither facility (1.78) nor physician (1.62) reimbursement are important. When asked about the current relative utilization of each modality, nephrologists felt that hospital-based hemodialysis (HD) is slightly overutilized (2.53), continuous ambulatory peritoneal dialysis (CAPD) is about right (3.00), while cycler peritoneal dialysis (PD) (3.53), community-based full (3.83) and self-care HD (3.91), and home HD (4.02) are underutilized. A hypothetical question about optimal distribution to maximize survival revealed that a type of HD should constitute 62.8% of the mix, with more emphasis on cycler PD (14.9%), community-based full care HD (13.8%), self-care HD (14.5%), and home HD (9.0%) than is current practice. However, when the goal was to maximize cost effectiveness, HD fell slightly to 57.8%.

Conclusions

These survey results suggest that the current national average 66%/34% HD/PD ratio is reasonable. However, there appears to be a consensus that Canada could evolve to a more cost-effective, community-based dialysis system without compromising patient outcomes.

Adequacy Targets Can be Met in Anuric Patients by Automated Peritoneal Dialysis: Baseline Data from Eapos

♦ Objective

Conventional continuous ambulatory peritoneal dialysis (CAPD) in patients without residual renal function and with high solute transport is associated with worse clinical outcomes. Automated peritoneal dialysis (APD) has the potential to improve both solute clearance and ultrafiltration in these circumstances, but its efficacy as a treatment modality is unknown. The European Automated Peritoneal Dialysis Outcomes Study (EAPOS) is a 2-year, prospective, European multi-center study designed to determine APD feasibility and clinical outcomes in anuric patients. The present article describes the baseline data for patients recruited into the study.

♦ Design

All PD patients treated in the participating centers were screened for inclusion criteria [urinary output < 100 mL/24 h, or residual renal function (RRF) < 1 mL/min, or both]. After enrollment, changes were made to the dialysis prescription to achieve a weekly creatinine clearance above 60 L per 1.73 m2 and an ultrafiltration rate above 750 mL in 24 hours.

♦ Setting

The study is being conducted in 26 dialysis centers in 13 European countries.

♦ Baseline Data Collection

The information collected includes patient demographics, dialysis prescription, achieved weekly creatinine clearance, and 24-hour ultra-filtration (UF).

♦ Results

The study enrolled 177 anuric patients. Median dialysis duration before enrollment was 22.5 months (range: 0 – 285 months). Mean solute transport measured as the dialysate-to-plasma ratio of creatinine (D/PCr) was 0.74 ± 0.12. Patients received APD for a median of 9.0 hours overnight (range: 7 – 12 hours) using a median of 11.0 L of fluid (range: 6 – 28.75 L). Median daytime volume was 4.0 L (range: 0.0 – 9.0 L). Tidal dialysis was used in 26 patients, and icodextrin in 86 patients. At baseline, before treatment optimization, the weekly mean total creatinine clearance was 65.2 ± 14.4 L/1.73 m2, with 105 patients (60%) achieving the target of more than 60 L/1.73 m2. At baseline, 81% of patients with high transport, 69% with high-average transport, and 40% with low-average transport met the target. At baseline, 70% of patients with a body surface area (BSA) below 1.7 m2, 60% with a BSA of 1.7 – 2.0 m2, and 56% with a BSA above 2.0 m2 achieved 60 L/1.73 m2 weekly. Median UF was 1090 mL/24 h, and 75% of patients achieved the UF target of more than 750 mL/24 h.

♦ Conclusion

This baseline analysis of anuric patients recruited into the EAPOS study demonstrates that a high proportion of anuric patients on APD can achieve dialysis and ultrafiltration targets using a variety of regimes. This 2-year follow-up study aims to optimize APD prescription to reach predefined clearance and ultrafiltration targets, and to observe the resulting clinical outcomes.

A Comparison of Peritoneal Equilibration Tests Performed 1 and 4 Weeks after PD Commencement

Objective

The aim of this study was to prospectively evaluate the ability of a peritoneal equilibration test (PET) performed in the first week of peritoneal dialysis (PD) to predict subsequent transport status, as determined by a PET at 4 weeks and >1 year after PD commencement.

Design

Prospective observational study of an incident PD cohort at a single center.

Setting

Tertiary-care institutional dialysis center.

Participants

The study included 50 consecutive patients commencing PD at the Princess Alexandra Hospital between 25/2/2001 and 14/5/2003 (mean age 60.9 ± 12.2 years, 54% male, 92% Caucasian, 38% diabetic). All patients were initially prescribed continuous ambulatory PD.

Main Measurements

Measurements performed during paired PETs included dialysate-to-plasma ratios of urea (D/P urea) and creatinine (D/P creatinine) at 4 hours, the ratio of dialysate glucose concentrations at 0 and 4 hours (D/D0glucose), and drain volumes at 4 hours.

Results

When paired 1-week and 1-month PET data were analyzed, significant changes were observed in measured D/P urea (0.91 ± 0.07 vs 0.94 ± 0.07 respectively; p < 0.05), D/P creatinine (0.55 ± 0.12 vs 0.66 ± 0.11, p < 0.001), and D/D0glucose (0.38 ± 0.08 vs 0.36 ± 0.10, p < 0.05). Using Bland–Altman analysis, the repeatability coefficients were 0.17, 0.20, and 0.13, respectively. Agreement between 1-week and 1-month PET measurements with respect to peritoneal transport category was moderate for D/D0glucose (weighted κ 0.52), but poor for D/P urea (0.30), D/P creatinine (0.35), and drain volumes (0.20). The PET measurements performed more than 1 year following PD commencement ( n = 28) generally agreed closely with 1-month measurements, and poorly with 1-week measurements.

Conclusions

Peritoneal transport characteristics change significantly within the first month of PD. PETs carried out during this time should be considered preliminary and should be confirmed by a PET 4 weeks later. Nevertheless, performing an early D/D0glucose measurement at 1 week predicted ultimate transport status sufficiently well to facilitate early clinical decision-making about optimal PD modality while patients were still receiving PD training. On the other hand, the widespread practice of using measured drain volumes in the first week to predict ultimate transport category is highly inaccurate and not recommended.

Volume management as a key dimension of a high-quality PD prescription

BACKGROUND

Appropriate volume control is one of the key goals in a peritoneal dialysis (PD) prescription. As such it is an important component of the International Society of Peritoneal Dialysis (ISPD) guideline for "High-quality PD prescription" necessitating a review of the literature on volume management. The workgroup recognized the importance of including within its scope measures of volume status and blood pressure in prescribing high-quality PD therapy.

METHODS

A Medline and PubMed search for publications addressing volume status and its management in PD since the publication of the 2015 ISPD Adult Cardiovascular and Metabolic Guidelines, from October 2014 through to July 2019, was conducted.

RESULTS

There were no randomized controlled trials on blood pressure intervention and six randomized trials of bioimpedance-guided volume management. Generally, all studies were of small sample size, short duration, and used surrogate markers as primary outcomes. As a consequence, only "practice points" were drawn. High-quality goal-directed PD prescription should aim to achieve and maintain clinical euvolemia taking residual kidney function and its preservation into account, so that both fluid removal from peritoneal ultrafiltration and urine output are considered and residual kidney function is not compromised. Blood pressure should be included as a key objective parameter in assessing the quality of PD prescription but there is currently no evidence for a specific target in PD. Clinical examination remains the keystone of routine clinical care.

CONCLUSIONS

High-quality goal-directed PD prescription should include volume management as one of the key dimensions.

International comparison of peritoneal dialysis prescriptions from the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS)

Background:

We describe peritoneal dialysis (PD) prescription variations among Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) participants on continuous ambulatory PD (CAPD) and automated PD (APD; n = 4657) from Australia/New Zealand (A/NZ), Canada, Japan, Thailand, United Kingdom (UK), and United States (US).

Results:

CAPD was more commonly used in Thailand and Japan, while APD predominated over CAPD in A/NZ, Canada, the US, and the UK. Total prescribed PD volume normalized to the surface area was the highest in Thailand and the lowest in Japan (for both APD and CAPD) and the UK (for CAPD). PD patients from Thailand had the lowest residual urine volume and residual renal urea clearance, yet achieved the highest dialysis urea clearance. Japanese patients had the lowest dialysis urea clearances for both APD and CAPD. Despite having similar urine volumes to patients in A/NZ, Canada, Japan, and the UK, US CAPD and APD patients used 2.5% and 3.86% glucose PD solutions more frequently, whereas fewer than 25% of these patients used icodextrin. Over half of the patients in A/NZ, Canada, the UK, and Japan used icodextrin, whereas it was hardly used in Thailand. Japan and Thailand were more likely to use 1.5% glucose solutions for their PD prescription.

Conclusions:

There are considerable international variations in PD modality use and prescription patterns that translate into important differences in achieved dialysis clearances. Ongoing recruitment of additional PDOPPS participants and accrual of follow-up time will allow us to test the associations between specific PD prescription regimens and clinical and patient-reported outcomes.

Estimating the Fraction of First-Year Hemodialysis Deaths Attributable to Potentially Modifiable Risk Factors: Results from the DOPPS

PURPOSE

Mortality among first-year hemodialysis (HD) patients remains unacceptably high. To address this problem, we estimate the proportions of early HD deaths that are potentially preventable by modifying known risk factors.

METHODS

We included 15,891 HD patients (within 60 days of starting HD) from 21 countries in the Dialysis Outcomes and Practice Patterns Study (1996-2015), a prospective cohort study. Using Cox regression adjusted for potential confounders, we estimated the fraction of first-year deaths attributable to one or more of twelve modifiable risk factors (the population attributable fraction, AF) identified from the published literature by comparing predicted survival based on risk factors observed vs counterfactually set to reference levels.

RESULTS

The highest AFs were for catheter use (22%), albumin <3.5 g/dL (19%), and creatinine <6 mg/dL (12%). AFs were 5%-9% for no pre-HD nephrology care, no residual urine volume, systolic blood pressure <130 or ≥160 mm Hg, phosphorus <3.5 or ≥5.5 mg/dL, hemoglobin <10 or ≥12 g/dL, and white blood cell count >10,000/μL. AFs for ferritin, calcium, and PTH were <3%. Overall, 65% (95% CI: 59%-71%) of deaths were attributable to these 12 risk factors. Additionally, the AF for C-reactive protein >10 mg/L was 21% in facilities where it was routinely measured.

CONCLUSION

A substantial proportion of first-year HD deaths could be prevented by successfully modifying a few risk factors. Highest priorities should be decreasing catheter use and limiting malnutrition/inflammation whenever possible.

Higher eGFR at Dialysis Initiation Is Not Associated with a Survival Benefit in Children

BACKGROUND

Study findings suggest that initiating dialysis at a higher eGFR level in adults with ESRD does not improve survival. It is less clear whether starting dialysis at a higher eGFR is associated with a survival benefit in children with CKD.

METHODS

To investigate this issue, we performed a retrospective cohort study of pediatric patients aged 1-18 years who, according to the US Renal Data System, started dialysis between 1995 and 2015. The primary predictor was eGFR at the time of dialysis initiation, categorized as higher (eGFR>10 ml/min per 1.73 m²) versus lower eGFR (eGFR≤10 ml/min per 1.73 m²).

RESULTS

Of 15,170 children, 4327 (29%) had a higher eGFR (median eGFR, 12.8 ml/min per 1.73 m²) at dialysis initiation. Compared with children with a lower eGFR (median eGFR, 6.5 ml/min per 1.73 m²), those with a higher eGFR at dialysis initiation were more often white, girls, underweight or obese, and more likely to have GN as the cause of ESRD. The risk of death was 1.36 times higher (95% confidence interval, 1.24 to 1.50) among children with a higher (versus lower) eGFR at dialysis initiation. The association between timing of dialysis and survival differed by treatment modality-hemodialysis versus peritoneal dialysis (P<0.001 for interaction)-and was stronger among children initially treated with hemodialysis (hazard ratio, 1.56, 95% confidence interval, 1.39 to 1.75; versus hazard ratio, 1.07, 95% confidence interval, 0.91 to 1.25; respectively).

CONCLUSIONS

In children with ESRD, a higher eGFR at dialysis initiation is associated with lower survival, particularly among children whose initial treatment modality is hemodialysis.

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.

IHDIP: a controlled randomized trial to assess the security and effectiveness of the incremental hemodialysis in incident patients

BACKGROUND

Most people who make the transition to renal replacement therapy (RRT) are treated with a fixed dose thrice-weekly hemodialysis réegimen, without considering their residual kidney function (RKF). Recent papers inform us that incremental hemodialysis is associated with preservation of RKF, whenever compared with conventional hemodialysis. The objective of the present controlled randomized trial (RCT) is to determine if start HD with one sessions per week (1-Wk/HD), it is associated with better patient survival and other safety parameters.

METHODS/DESIGN

IHDIP is a multicenter RCT experimental open trial. It is randomized in a 1:1 ratio and controlled through usual clinical practice, with a low intervention level and non-commercial. It includes 152 incident patients older than 18 years, with a RRF of ≥4 ml/min/1.73 m2, measured by renal clearance of urea (KrU). The intervention group includes 76 patients who will start with incremental HD (1-Wk/HD). The control group includes 76 patients who will start with thrice-weekly hemodialysis régimen. The primary outcome is assessing the survival rate, while the secondary outcomes are the morbidity rate, the clinical parameters, the quality of life and the efficiency.

DISCUSSION

This study will enable to know the number of sessions a patient should receive when starting HD, depending on his RRF. The potentially important clinical and financial implications of incremental hemodialysis warrant this RCT.

TRIAL REGISTRATION

U.S. National Institutes of Health, ClinicalTrials.gov . Number: NCT03239808 , completed 13/04/2017.

SPONSOR

Foundation for Training and Research of Health Professionals of Extremadura.

Association between timing of peritoneal dialysis initiation and mortality in end-stage renal disease

Despite the widespread use of chronic dialysis for end-stage renal disease (ESRD), there is no consensus on the optimal timing of initiating renal replacement therapy. Over the past decade, a worldwide trend toward increasing glomerular filtration rate at the initiation of dialysis has been noted. However, available data indicate that early dialysis has no survival benefit or is harmful. Peritoneal dialysis (PD) is one alternative for ESRD and has potential survival factors different from those of hemodialysis. The association between the timing of PD initiation and survival is unclear. This review examines the effect of the timing of dialysis on clinical outcomes in PD patients.

Trends in anemia care in non-dialysis-dependent chronic kidney disease (CKD) patients in the United States (2006-2015)

BACKGROUND

The objective of the study was to examine overall anemia management trends in non-dialysis patients with chronic kidney disease (CKD) from 2006 to 2015, and to evaluate the impact of Trial to Reduced Cardiovascular Events with Ananesp Therapy (TREAT)'s study results (October 2009) and the US Food and Drug Administration (FDA)'s (June 2011) safety warnings and guidelines on the use of ESA therapy in the current treatment of anemia.

METHODS

A retrospective cohort analysis of anemia management in CKD patients using Truven MarketScan Commercial and Medicare Supplemental databases was conducted. Monthly rates and types of anemia treatment for post-TREAT and post-FDA safety warning periods were compared to pre-TREAT period. Anemia management included ESA, intravenous iron, and blood transfusion. A time-series analysis using Autoregressive Integrated Moving Average (ARIMA) model and a Generalized Estimating Equation (GEE) model were used.

RESULTS

Between 2006 and 2015, CKD patients were increasingly less likely to be treated with ESAs, more likely to receive intravenous iron supplementation, and blood transfusions. The adjusted probabilities of prescribing ESAs were 31% (odds ratio (OR) = 0.69, 95% confidence interval (CI): 0.67-0.71) and 59% (OR = 0.41, 95% CI: 0.40, 0.42) lower in the post-TREAT and post-FDA warning periods compared to pre-TREAT period. The probability of prescribing intravenous iron was increased in the post-FDA warning period (OR = 1.11, 95% CI: 1.03-1.19) although the increase was not statistically significant in the post-TREAT period (OR = 1.03, 95% CI: 0.94-1.12). The probabilities of prescribing blood transfusion during the post-TREAT and post-FDA warning periods increased by 14% (OR = 1.14, 95% CI: 1.06-1.23) and 31% (OR = 1.31, 95% CI: 1.22-1.39), respectively. Similar trends of prescribing ESAs and iron supplementations were observed in commercially insured CKD patients but the use of blood transfusions did not increase.

CONCLUSIONS

After the 2011 FDA safety warnings, the use of ESA continued to decrease while the use of iron supplementation continued to increase. The use of blood transfusions increased significantly in Medicare patients while it remained stable in commercially insured patients. Results suggest the TREAT publication had effected treatment of anemia prior to the FDA warning but the FDA warning solidified TREAT's recommendations for anemia treatment for non- dialysis dependent CKD patients.

Correlation between Dt/V derived from ionic dialysance and blood-driven Kt/V of urea in African-American hemodialysis patients, based on body weight and ultrafiltration volume

Background

The Dt/V obtained by using ionic dialysance (D) as a surrogate for urea clearance (K) is a well-validated adjunct measure of hemodialysis adequacy, with a variable level of correlation with urea-based Kt/V. However, this correlation has not been examined based on patients’ body size and ultrafiltration (UF) volume during the dialysis session.

Methods

Simultaneous evaluations of online Dt/V and single-pool variable-volume urea Kt/V were made. Patients were categorized into three subgroups based on their weight (<60, 60–80 and ≥80 kg), body mass index (<25, 25–30 and >30 kg/m²) and UF volume (<1.5, 1.5–3 and >3 L). The correlation between Dt/V and Kt/V was evaluated for the entire cohort per dialysis session in each subgroup.

Results

Mean Kt/V was greater than the mean Dt/V (1.72 versus 1.50, P < 0.001), with an overall correlation r value of 0.602. This correlation was stronger in the medium weight group versus lower and higher weights. The correlation between Dt/V and Kt/V was inversely related to the UF volume (r = 0.698, 0.621 and 0.558 for those with UF volume of <1.5, 1.5–3.0 and >3 L, respectively). A total of 99.3% of patients with Dt/V of >1.2 also had Kt/V >1.2 and 9.5% of those with Dt/V <1.2 had their Kt/V <1.2.

Conclusions

There is a moderate degree of correlation between Dt/V and Kt/V in African-American hemodialysis patients, which is impacted by body size and UF volume. A Dt/V of >1.2 strongly predicts adequate dialysis as defined by Kt/V of >1.2.

Clinical Results of Arteriovenous Fistulas Constructed Using Autologous Vessels in End-Stage Renal Disease Patients on Hemodialysis

Background

For hemodialysis patients with end-stage renal disease (ESRD), it is important to construct an efficient vascular access with a superior patency rate. This study investigated the factors influencing the efficiency of arteriovenous fistulas (AVFs) constructed using an autologous vessel and evaluated the necessity of ultrasonography as a preoperative tool for AVF construction.

Methods

A retrospective analysis was performed of 250 patients in whom an AVF was constructed using an autologous vessel due to ESRD at our institution from January 2009 to April 2016.

Results

The 1-, 3-, and 5-year patency rates for all subjects were 87.6%, 85.6%, and 84.4%, respectively. The patients who underwent a preoperative evaluation of their vessels via ultrasonography had better patency rates than those who did not. Superior patency rates were found in patients under 65 years of age or with an anastomotic vein diameter of 3 mm or more. The 1-year patency rate and the diameter of the anastomotic vein showed a positive relationship.

Conclusion

Ultrasonography is strongly recommended for AVF construction, and efforts should be made to increase the patency rate in patients over 65. Superior clinical results can be expected when an AVF is made using an autologous vessel with an anastomotic vein diameter of at least 3 mm.

A Review of Percutaneous Transluminal Angioplasty in Hemodialysis Fistula

The number of patients in dialysis increases every year. In this review, we will evaluate the role of percutaneous transluminal angioplasty (PTA) according to patency of arteriovenous fistula and grafts. The main indication of PΤΑ is stenosis > 50% or obstruction of the vascular lumen of an arteriovenous fistula and graft. It is usually performed under local anesthesia. The infection rate is as low as the number of complications. Fistula can be used in dialysis in the same day without the need for a central venous catheter. Primary patency is >50% in the first year while primary assisted patency is 80-90% in the same time period. Repeated PTA is as durable as the primary PTA. An early PTA carries a risk of new interventions. Cutting balloon can be used as a second-line method. Stents and covered stents are kept for the management of complications and central outflow venous stenosis. PTA is the treatment of choice for stenosis or obstruction of dialysis fistulas. Repeated PTA may be needed for better patency. Drug eluting balloon may become the future in PTA of dialysis fistula, but more trials are needed.

Incremental start to PD as experienced in Italy: results of censuses carried out from 2005 to 2014

BACKGROUND

It is not known how widely used in Italy an incremental start to in peritoneal dialysis (Incr-PD) is.

METHODS

By analyzing the peritoneal dialysis (PD) censuses conducted by the PD Study Group (GSDP-SIN) for the years 2005, 2008, 2010, 2012 and 2014 in all the Centers performing PD in Italy, the use of Incr-PD, i.e. continuous ambulatory peritoneal dialysis (CAPD) with 1 or 2 exchanges/day or automated peritoneal dialysis (APD) with 3-4 sessions/week, was examined among incident PD patients.

RESULTS

In 2014 PD was started in Italy by 1,652 patients, 455 (27.5%) of whom incrementally (Incr-CAPD 82.2% vs. Incr-APD 17.8%). Incr-PD was used in 53.5% of the 225 Centers. The number of patients and of Centers using Incr-DP increased constantly over the years up to 2012 (in 2005 Incr-PD was used in 33.4% of Centers, and in 11.9% of patients). The use of Incr-PD was greater in Centers with a more extensive PD program and greater use of PD in general. The most widely-used modality in Incr-PD was CAPD.

CONCLUSIONS

Incr-PD is used in Italy in a large number of incident PD patients. The reasons for this increase need to be clarified, as current adequacy targets are based on full-dose studies with a very low glomerular filtration rate (GFR).

Explaining trends and variation in timing of dialysis initiation in the United States

The United States Renal Data System (USRDS) registry of end-stage renal disease has often been used to study the timing of dialysis initiation, measured by estimated glomerular filtration rate (eGFR) at dialysis initiation. We conducted an observational study and examined how well variables in the USRDS database explain the trends and variation in eGFR at dialysis initiation.We identified 971,481 patients who initiated dialysis between 1995 and 2012 in the USRDS registry.The mean eGFR at dialysis initiation monotonically rose from 7.7 in 1995 to 11.1 in 2009, and then leveled off to 10.9 mL/min/1.73 m in 2012. The trend of rising, then leveling off was similar across all subgroups studied. Substantial variation in eGFR at dialysis initiation was observed, with standard deviation of 4.38 (95% CI: 2.0-18.4). A total of 11.4% of the total variation occurred across physicians and 88.6% within physicians. Adjustment for measured factors only modestly decreased the total variation. Of the total variance, 10.7% was explained by measured patient-level variables and 1.2% by measured physician and other factors, while 9.2% of physician-level variation and 78.9% of patient-level variation remained unexplained. The extent of variation explained by measured variables was similar over the entire study period.The finding that the majority of variation in eGFR at dialysis initiation is unexplained by measured variables casts doubt on how well eGFR serves as a measure for "timing" of dialysis initiation, and it indicates the need to collect more focused data to gain understanding of factors that affect timing of dialysis initiation in the US.

The Use of Incremental Peritoneal Dialysis in a Large Contemporary Peritoneal Dialysis Program

BACKGROUND

The use of an incremental peritoneal dialysis (PD) strategy in a large contemporary patient population has not been described.

OBJECTIVE

We report the use of this strategy in clinical practice, the prescriptions required, and the clearances achieved in a large center which has routinely used this approach for more than 10 years.

DESIGN

This is a cross-sectional observational study.

SETTING

A single large Canadian academic center.

PATIENTS

This study collected data on 124 prevalent PD patients at a single Canadian academic center.

METHODS AND MEASUREMENTS

The proportion of patients who achieve the clearance target on a low clearance or incremental PD prescription; the actual PD prescriptions and consequent total, peritoneal, and renal urea clearances [Kt/V] achieved; and patient and technique survival and peritonitis rate in comparison with national and international reports.

RESULTS

Of the 124 prevalent PD patients in this PD unit, 106 (86%) were achieving the Kt/V target, and of these, 54 (44% of all patients) were doing so using incremental PD prescriptions. Fifty of these incremental PD patients were using automated PD (APD) with either no day dwell (68%) or less than 7 days a week treatment (12%) or both (20%). Patient survival in our PD unit was not different from that reported in Canada as a whole. Peritonitis rates were better than internationally recommended standards.

LIMITATIONS

This is an observational study with no randomized control group.

CONCLUSIONS

Incremental PD is feasible in a contemporary PD population treated mainly with APD. Almost half of the patients were able to achieve clearance targets while receiving less onerous and less costly low clearance prescriptions. We suggest that incremental PD should be widely used as a cost-effective strategy in PD.