Outcomes of Integrated Home Dialysis Care: Results From the Canadian Organ Replacement Register.

RATIONALE & OBJECTIVE: The integrated home dialysis model proposes the initiation of kidney replacement therapy (KRT) with peritoneal dialysis (PD) and a timely transition to home hemodialysis (HHD) after PD ends. We compared the outcomes of patients transitioning from PD to HHD with those initiating KRT with HHD. STUDY DESIGN: Observational analysis of the Canadian Organ Replacement Register (CORR). SETTINGS & PARTICIPANTS: All patients who initiated PD or HHD within the first 90 days of KRT between 2005 and 2018. EXPOSURE: Patients transitioning from PD to HHD (PD+HHD group) versus patients initiating KRT with HHD (HHD group). OUTCOME: (1) A composite of all-cause mortality and modality transfer (to in-center hemodialysis or PD for 90 days) and (2) all hospitalizations (considered as recurrent events). ANALYTICAL APPROACH: A propensity score analysis for which PD+HHD patients were matched 1:1 to (1) incident HHD patients ("incident-match" analysis) or (2) HHD patients with a KRT vintage at least equivalent to the vintage of PD+HHD patients at the transition time ("vintage-matched" analysis). Cause-specific hazards models (composite outcome) and shared frailty models (hospitalization) were used to compare groups. RESULTS: Among 63,327 individuals in the CORR, 163 PD+HHD patients (median of 1.9 years in PD) and 711 HHD patients were identified. In the incident-match analysis, compared to the HHD patients, the PD+HHD group had a similar risk of the composite outcome (HR, 0.88 [95% CI, 0.58-1.32]) and hospitalizations (HR, 1.04 [95% CI, 0.76-1.41]). In the vintage-match analysis, PD+HHD patients had a lower hazard for the composite outcome (HR, 0.61 [95% CI, 0.40-0.94]) but a similar hospitalization risk (HR, 0.85 [95% CI, 0.59-1.24]). LIMITATIONS: Risk of survivor bias in the PD+HHD cohort and residual confounding. CONCLUSIONS: Controlling for KRT vintage, the patients transitioning from PD to HHD had better clinical outcomes than the incident HHD patients. These data support the use of integrated home dialysis for patients initiating home-based KRT. PLAIN-LANGUAGE SUMMARY: The integrated home dialysis model proposes the initiation of dialysis with peritoneal dialysis (PD) and subsequent transition to home hemodialysis (HHD) once PD is no longer feasible. It allows patients to benefit from initial lifestyle advantages of PD and to continue home-based treatments after its termination. However, some patients may prefer to initiate dialysis with HHD from the outset. In this study, we compared the long-term clinical outcomes of both approaches using a large Canadian dialysis register. We found that both options led to a similar risk of hospitalization. In contrast, the PD-to-HHD model led to improved survival when controlling for the duration of kidney failure.

Impact of Prior Abdominal Procedures on Peritoneal Dialysis Catheter Outcomes: Findings From the North American Peritoneal Dialysis Catheter Registry.

RATIONALE & OBJECTIVE: A history of prior abdominal procedures may influence the likelihood of referral for peritoneal dialysis (PD) catheter insertion. To guide clinical decision making in this population, this study examined the association between prior abdominal procedures and outcomes in patients undergoing PD catheter insertion. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Adults undergoing their first PD catheter insertion between November 1, 2011, and November 1, 2020, at 11 institutions in Canada and the United States participating in the International Society for Peritoneal Dialysis North American Catheter Registry. EXPOSURE: Prior abdominal procedure(s) defined as any procedure that enters the peritoneal cavity. OUTCOMES: The primary outcome was time to the first of (1) abandonment of the PD catheter or (2) interruption/termination of PD. Secondary outcomes were rates of emergency room visits, hospitalizations, and procedures. ANALYTICAL APPROACH: Cumulative incidence curves were used to describe the risk over time, and an adjusted Cox proportional hazards model was used to estimate the association between the exposure and primary outcome. Models for count data were used to estimate the associations between the exposure and secondary outcomes. RESULTS: Of 855 patients who met the inclusion criteria, 31% had a history of a prior abdominal procedure and 20% experienced at least 1 PD catheter-related complication that led to the primary outcome. Prior abdominal procedures were not associated with an increased risk of the primary outcome (adjusted HR, 1.12; 95% CI, 0.68-1.84). Upper-abdominal procedures were associated with a higher adjusted hazard of the primary outcome, but there was no dose-response relationship concerning the number of procedures. There was no association between prior abdominal procedures and other secondary outcomes. LIMITATIONS: Observational study and cohort limited to a sample of patients believed to be potential candidates for PD catheter insertion. CONCLUSION: A history of prior abdominal procedure(s) does not appear to influence catheter outcomes following PD catheter insertion. Such a history should not be a contraindication to PD. PLAIN-LANGUAGE SUMMARY: Peritoneal dialysis (PD) is a life-saving therapy for individuals with kidney failure that can be done at home. PD requires the placement of a tube, or catheter, into the abdomen to allow the exchange of dialysis fluid during treatment. There is concern that individuals who have undergone prior abdominal procedures and are referred for a catheter might have scarring that could affect catheter function. In some institutions, they might not even be offered PD therapy as an option. In this study, we found that a history of prior abdominal procedures did not increase the risk of PD catheter complications and should not dissuade patients from choosing PD or providers from recommending it.

Home dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference.

Home dialysis modalities (home hemodialysis [HD] and peritoneal dialysis [PD]) are associated with greater patient autonomy and treatment satisfaction compared with in-center modalities, yet the level of home-dialysis use worldwide is low. Reasons for limited utilization are context-dependent, informed by local resources, dialysis costs, access to healthcare, health system policies, provider bias or preferences, cultural beliefs, individual lifestyle concerns, potential care-partner time, and financial burdens. In May 2021, KDIGO (Kidney Disease: Improving Global Outcomes) convened a controversies conference on home dialysis, focusing on how modality choice and distribution are determined and strategies to expand home-dialysis use. Participants recognized that expanding use of home dialysis within a given health system requires alignment of policy, fiscal resources, organizational structure, provider incentives, and accountability. Clinical outcomes across all dialysis modalities are largely similar, but for specific clinical measures, one modality may have advantages over another. Therefore, choice among available modalities is preference-sensitive, with consideration of quality of life, life goals, clinical characteristics, family or care-partner support, and living environment. Ideally, individuals, their care-partners, and their healthcare teams will employ shared decision-making in assessing initial and subsequent kidney failure treatment options. To meet this goal, iterative, high-quality education and support for healthcare professionals, patients, and care-partners are priorities. Everyone who faces dialysis should have access to home therapy. Facilitating universal access to home dialysis and expanding utilization requires alignment of policy considerations and resources at the dialysis-center level, with clear leadership from informed and motivated clinical teams.

Peritoneal Dialysis-Associated Peritonitis Trends Using Medicare Claims Data, 2013-2017.

RATIONALE & OBJECTIVE: The occurrence and consequences of peritoneal dialysis (PD)-associated peritonitis limit its use in populations with kidney failure. Studies of large clinical populations may enhance our understanding of peritonitis. To facilitate these studies we developed an approach to measuring peritonitis rates using Medicare claims data to characterize peritonitis trends and identify its clinical risk factors. STUDY DESIGN: Retrospective cohort study of PD-associated peritonitis. SETTING & PARTICIPANTS: US Renal Data System standard analysis files were used for claims, eligibility, modality, and demographic information. The sample consisted of patients receiving PD treated at some time between 2013 and 2017 who were covered by Medicare fee-for-service (FFS) insurance with paid claims for dialysis or hospital services. EXPOSURES/PREDICTORS: Peritonitis risk was characterized by year, age, sex, race, ethnicity, vintage of kidney replacement therapy, cause of kidney failure, and prior peritonitis episodes. OUTCOME: The major outcome was peritonitis, identified using ICD-9 and ICD-10 diagnosis codes. Closely spaced peritonitis claims (30 days) were aggregated into 1 peritonitis episode. ANALYTICAL APPROACH: Patient-level risk factors for peritonitis were modeled using Poisson regression. RESULTS: We identified 70,271 peritonitis episodes from 396,289 peritonitis claims. Although various codes were used to record an episode of peritonitis, none was used predominantly. Peritonitis episodes were often identified by multiple aggregated claims, with the mean and median claims per episode being 5.6 and 2, respectively. We found 40% of episodes were exclusively outpatient, 9% exclusively inpatient, and 16% were exclusively based on codes that do not clearly distinguish peritonitis from catheter infections/inflammation ("catheter codes"). The overall peritonitis rate was 0.54 episodes per patient-year (EPPY). The rate was 0.45 EPPY after excluding catheter codes and 0.35 EPPY when limited to episodes that only included claims from nephrologists or dialysis providers. The peritonitis rate declined by 5%/year and varied by patient factors including age (lower rates at higher ages), race (Black > White>Asian), and prior peritonitis episodes (higher rate with each prior episode). LIMITATIONS: Coding heterogeneity indicates a lack of standardization. Episodes based exclusively on catheter codes could represent false positives. Peritonitis episodes were not validated against symptoms or microbiologic data. CONCLUSIONS: PD-associated peritonitis rates decline over time and were lower among older patients. A claims-based approach offers a promising framework for the study of PD-associated peritonitis.

Association of single and serial measures of serum phosphorus with adverse outcomes in patients on peritoneal dialysis: results from the international PDOPPS.

BACKGROUND: While high serum phosphorus levels have been related to adverse outcomes in hemodialysis patients, further investigation is warranted in persons receiving peritoneal dialysis (PD). METHODS: Longitudinal data (2014-17) from the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS), a prospective cohort study, were used to examine associations of serum phosphorus with all-cause mortality and major adverse cardiovascular events via Cox regression adjusted for confounders. Serum phosphorus levels were parameterized by four methods: (i) baseline serum phosphorus; (ii) mean 6-month serum phosphorus; (iii) number of months with serum phosphorus >4.5 mg/dL; and (iv) mean area-under-the-curve of 6-month serum phosphorus control. RESULTS: The study included 5847 PD patients from seven countries; 9% of patients had baseline serum phosphorus <3.5 mg/dL, 24% had serum phosphorus ≥3.5 to ≤4.5 mg/dL, 30% had serum phosphorus >4.5 to <5.5 mg/dL, 20% had serum phosphorus ≥5.5 to <6.5 mg/dL, and 17% had serum phosphorus ≥6.5 mg/dL. Compared with patients with baseline serum phosphorus ≥3.5 to ≤4.5 mg/dL, the adjusted all-cause mortality hazard ratio (HR) was 1.19 (0.92,1.53) for patients with baseline serum phosphorus ≥5.5 to <6.5 mg/dL and HR was 1.53 (1.14,2.05) for serum phosphorus ≥6.5 mg/dL. Associations between serum phosphorus measurements over 6 months and clinical outcomes were even stronger than for a single measurement. CONCLUSIONS: Serum phosphorus >5.5 mg/dL was highly prevalent (37%) in PD patients, and higher serum phosphorus levels were a strong predictor of morbidity and death, particularly when considering serial phosphorus measurements. This highlights the need for improved treatment strategies in this population. Serial serum phosphorus measurements should be considered when assessing patients' risks of adverse outcomes.

Enhancing healthcare quality and outcomes for peritoneal dialysis patients in Thailand: An evaluation of key performance indicators and PDOPPS cohort representativeness.

AIM: To assess whether the peritoneal dialysis (PD) centres included in the Peritoneal Dialysis Outcomes and Practise Patterns Study (PDOPPS) in Thailand are representative of other PD centres in the country, based on 8 key performance indicators (KPIs 1-8). METHODS: A retrospective analysis was conducted comparing PD-related clinical outcomes between PD centres included in the PDOPPS (the PDOPPS group) and those not included (the non-PDOPPS group) from January 2018 to December 2019. Logistic regression analysis was used to identify predictors associated with achieving the target KPIs. RESULTS: Of 181 PD centres, 22 (12%) were included in the PDOPPS. PD centres in the PDOPPS group were larger and tended to serve more PD patients than those in the non-PDOPPS group. However, the process and outcome KPIs (KPIs 1-8) were comparable between the 2 groups. Large hospitals (≥120 beds), providing care to ≥100 PD cases and having experience for >10 years were independent predictors of achieving the peritonitis rate target of <0.5 episodes/year. Most PD centres in Thailand showed weaknesses in off-target haemoglobin levels and culture-negative peritonitis rate. CONCLUSIONS: The PD centres included in Thai PDOPPS were found to be representative of other PD centres in Thailand in terms of clinical outcomes. Thus, Thai PDOPPS findings may apply to the broader PD population in Thailand.

Constipation and clinical outcomes in peritoneal dialysis: Results from Thailand PDOPPS.

BACKGROUND: Patient-reported outcome measures (PROMs) are widely recognized as valuable predictors of clinical outcomes in peritoneal dialysis (PD). Our study aimed to explore the connections between patient-reported constipation and clinical outcomes. METHODS: We assessed constipation in patients across 22 facilities participating in the Thailand Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) from 2014 to 2017. Constipation diagnosis utilized objective assessment tools such as the Bristol stool form scale (BSFS) and a self-reported questionnaire known as the constipation severity score (CSS). The BSFS is a 7-level scale that visually inspects feces based on texture and morphology, while the CSS measures constipation duration and severity using a 5-point Likert scale for various factors. We employed Cox proportional hazards model regression to determine the associations between constipation and clinical outcomes, including mortality, hemodialysis (HD) transfer and peritonitis. RESULTS: Among 975 randomly selected PD patients from 22 facilities, 845 provided written informed consent, and 729 completed CSS questionnaire. Constipation was prevalent in the PD population (13%), particularly among older patients, those who were caregiver dependent, had diabetes and poorer nutritional status (indicated by lower time-averaged serum albumin, potassium, creatinine and phosphate concentrations). Twenty-seven percent of which experiencing symptoms of constipation for over a year. Notably, self-reported constipation at baseline was significantly associated with a shorter time to first peritonitis and higher rates of peritonitis and death. However, no significant association was found between constipation and HD transfer after adjusting for various factors, including age, gender, PD vintage, comorbidities, shared frailty by study sites and serum albumin. CONCLUSION: Patient-reported constipation independently correlated with increased risks of peritonitis and all-cause mortality, though no such correlation was observed with HD transfer. These findings underscore the need for further investigation to identify effective interventions for constipation in PD patients.

Immunosuppressant Medication Use in Patients with Kidney Allograft Failure: A Prospective Multicenter Canadian Cohort Study.

BACKGROUND: Patients with kidney transplant failure have a high risk of hospitalization and death due to infection. The optimal use of immunosuppressants after transplant failure remains uncertain and clinical practice varies widely. METHODS: This prospective cohort study enrolled patients within 21 days of starting dialysis after transplant failure in 16 Canadian centers. Immunosuppressant medication use, death, hospitalized infection, rejection of the failed allograft, and anti-HLA panel reactive antibodies were determined at 1, 3, 6, and 12 months and and then twice yearly until death, repeat transplantation, or loss to follow-up. RESULTS: The 269 study patients were followed for a median of 558 days. There were 33 deaths, 143 patients hospitalized for infection, and 21 rejections. Most patients (65%) continued immunosuppressants, 20% continued prednisone only, and 15% discontinued all immunosuppressants. In multivariable models, patients who continued immunosuppressants had a lower risk of death (hazard ratio [HR], 0.40; 95% confidence interval [CI], 0.17 to 0.93) and were not at increased risk of hospitalized infection (HR, 1.81; 95% CI, 0.82 to 4.0) compared with patients who discontinued all immunosuppressants or continued prednisone only. The mean class I and class II panel reactive antibodies increased from 11% to 27% and from 25% to 47%, respectively, but did not differ by immunosuppressant use. Continuation of immunosuppressants was not protective of rejection of the failed allograft (HR, 0.81; 95% CI, 0.22 to 2.94). CONCLUSIONS: Prolonged use of immunosuppressants >1 year after transplant failure was not associated with a higher risk of death or hospitalized infection but was insufficient to prevent higher anti-HLA antibodies or rejection of the failed allograft.

Vaccine Effectiveness Against SARS-CoV-2 Infection and Severe Outcomes in the Maintenance Dialysis Population in Ontario, Canada.

BACKGROUND: Vaccination studies in the hemodialysis population have demonstrated decreased antibody response compared with healthy controls, but vaccine effectiveness for preventing SARS-CoV-2 infection and severe disease is undetermined. METHODS: We conducted a retrospective cohort study in the province of Ontario, Canada, between December 21, 2020, and June 30, 2021. Receipt of vaccine, SARS-CoV-2 infection, and related severe outcomes (hospitalization or death) were determined from provincial health administrative data. Receipt of one and two doses of vaccine were modeled in a time-varying cause-specific Cox proportional hazards model, adjusting for baseline characteristics, background community infection rates, and censoring for non-COVID death, recovered kidney function, transfer out of province, solid organ transplant, and withdrawal from dialysis. RESULTS: Among 13,759 individuals receiving maintenance dialysis, 2403 (17%) were unvaccinated and 11,356 (83%) had received at least one dose by June 30, 2021. Vaccine types were BNT162b2 (n=8455, 74%) and mRNA-1273 (n=2901, 26%); median time between the first and second dose was 36 days (IQR 28-51). The adjusted hazard ratio (HR) for SARS-CoV-2 infection and severe outcomes for one dose compared with unvaccinated was 0.59 (95% CI, 0.46 to 0.76) and 0.54 (95% CI, 0.37 to 0.77), respectively, and for two doses compared with unvaccinated was 0.31 (95% CI, 0.22 to 0.42) and 0.17 (95% CI, 0.1 to 0.3), respectively. There were no significant differences in vaccine effectiveness among age groups, dialysis modality, or vaccine type. CONCLUSIONS: COVID-19 vaccination is effective in the dialysis population to prevent SARS-CoV-2 infection and severe outcomes, despite concerns about suboptimal antibody responses.

Impact of Bioelectrical Impedance-Guided Fluid Management and Vitamin D Supplementation on Left Ventricular Mass in Patients Receiving Peritoneal Dialysis: A Randomized Controlled Trial.

RATIONALE & OBJECTIVE: Hypervolemia and vitamin D deficiency occur frequently in patients receiving peritoneal dialysis and may contribute to left ventricular (LV) hypertrophy. The effect of bioelectrical impedance analysis (BIA)-guided volume management or vitamin D supplementation on LV mass among those receiving peritoneal dialysis is uncertain. STUDY DESIGN: Two-by-two factorial randomized controlled trial. SETTING & PARTICIPANTS: Sixty-five patients receiving maintenance peritoneal dialysis. INTERVENTION: BIA-guided volume management versus usual care and oral cholecalciferol 50,000 U weekly for 8 weeks followed by 10,000 U weekly for 44 weeks or matching placebo. OUTCOME: Change in LV mass at 1 year measured by cardiac magnetic resonance imaging. RESULTS: Total body water decreased by 0.9 + 2.4 (SD) L in the BIA group compared with a 1.5 ± 3.4 L increase in the usual care group (adjusted between-group difference: -2.4 [95% CI, -4.1 to -0.68] L, P = 0.01). LV mass increased by 1.3 ± 14.3 g in the BIA group and decreased by 2.4 ± 37.7 g in the usual care group (between-group difference: +2.2 [95% CI, -13.9 to 18.3] g, P = 0.8). Serum 25-hydroxyvitamin D concentration increased by a mean of 17.2 ± 30.8 nmol/L in the cholecalciferol group and declined by 8.2 ± 24.3 nmol/L in the placebo group (between-group difference: 28.3 [95% CI, 17.2-39.4] nmol/L, P < 0.001). LV mass decreased by 3.0 ± 28.1 g in the cholecalciferol group and increased by 2.0 ± 31.2 g in the placebo group (between-group difference: -4.5 [95% CI, -20.4 to 11.5] g, P = 0.6). LIMITATIONS: Relatively small sample size with larger than expected variation in change in LV mass. CONCLUSIONS: BIA-guided volume management had a modest impact on volume status with no effect on the change in LV mass. Vitamin D supplementation increased serum vitamin D concentration but had no effect on LV mass. FUNDING: Unrestricted Baxter International extramural grant and the Kidney Foundation of Canada. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT01045980.

Efficacy of Potassium Supplementation in Hypokalemic Patients Receiving Peritoneal Dialysis: A Randomized Controlled Trial.

RATIONALE & OBJECTIVE: Hypokalemia is a common electrolyte abnormality in patients on peritoneal dialysis (PD) and has been associated with increased risks of peritonitis and death. Whether correction of hypokalemia improves these outcomes is unknown. STUDY DESIGN: Multicenter, open-label, prospective, randomized controlled trial. SETTING & PARTICIPANTS: Adult (aged ≥18 years) PD patients with hypokalemia (defined as at least 3 values or an average value <3.5 mEq/L in the past 6 months). Randomization was stratified according to center and residual urine output (≤100 or >100 mL/day). INTERVENTIONS: Random assignment to either protocol-based potassium supplementation (titratable dose of oral potassium chloride to maintain serum potassium of 4-5 mEq/L) or conventional potassium supplementation (reactive supplementation when serum potassium is <3.5 mEq/L) over 52 weeks. Treatment groups were compared using intention-to-treat analyses implemented using Cox proportional hazards regression. OUTCOME: The primary outcome was time from randomization to first peritonitis episode (any organism). Secondary outcomes were all-cause mortality, cardiovascular mortality, hospitalization, and conversion to hemodialysis. RESULTS: A total of 167 patients with time-averaged serum potassium concentrations of 3.33 ± 0.28 mEq/L were enrolled from 6 PD centers: 85 were assigned to receive protocol-based treatment, and 82 were assigned to conventional treatment. The median follow-up time was 401 (IQR, 315-417) days. During the study period, serum potassium levels in the protocol-based treatment group increased to 4.36 ± 0.70 mEq/L compared with 3.57 ± 0.65 mEq/L in the group treated conventionally (mean difference, 0.66 [95% CI, 0.53-0.79] mEq/L; P < 0.001). The median time to first peritonitis episode was significantly longer in the protocol-based group (223 [IQR, 147-247] vs 133 [IQR, 41-197] days, P = 0.03). Compared with conventional treatment, the protocol-based group had a significantly lower hazard of peritonitis (HR, 0.47 [95% CI, 0.24-0.93]) but did not differ significantly with respect to any of the secondary outcomes. Asymptomatic hyperkalemia (>6 mEq/L) without characteristic electrocardiographic changes occurred in 3 patients (4%) in the protocol-based treatment group. LIMITATIONS: Not double-masked. CONCLUSIONS: Compared with reactive potassium supplementation when the serum potassium level falls below 3.5 mEq/L, protocol-based oral potassium treatment to maintain a serum potassium concentration in the range of 4-5 mEq/L may reduce the risk of peritonitis in patients receiving PD who have hypokalemia. TRIAL REGISTRATION: Registered at the Thai Clinical Trials Registry with study number TCTR20190725004.

Variation in Peritoneal Dialysis-Related Peritonitis Outcomes in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).

RATIONALE & OBJECTIVE: Peritoneal dialysis (PD)-associated peritonitis is a significant PD-related complication. We describe the likelihood of cure after a peritonitis episode, exploring its association with various patient, peritonitis, and treatment characteristics. STUDY DESIGN: Observational prospective cohort study. SETTING & PARTICIPANTS: 1,631 peritonitis episodes (1,190 patients, 126 facilities) in Australia, New Zealand, Canada, Japan, Thailand, the United Kingdom, and the United States. EXPOSURE: Patient characteristics (demographics, patient history, laboratory values), peritonitis characteristics (organism category, concomitant exit-site infection), dialysis center characteristics (use of icodextrin and low glucose degradation product solutions, policies regarding antibiotic self-administration), and peritonitis treatment characteristics (antibiotic used). OUTCOME: Cure, defined as absence of death, transfer to hemodialysis (HD), PD catheter removal, relapse, or recurrent peritonitis within 50 days of a peritonitis episode. ANALYTICAL APPROACH: Mixed-effects logistic models. RESULTS: Overall, 65% of episodes resulted in a cure. Adjusted odds ratios (AOR) for cure were similar across countries (range, 54%-68%), by age, sex, dialysis vintage, and diabetes status. Compared with Gram-positive peritonitis, the odds of cure were lower for Gram-negative (AOR, 0.41 [95% CI, 0.30-0.57]), polymicrobial (AOR, 0.30 [95% CI, 0.20-0.47]), and fungal (AOR, 0.01 [95% CI, 0.00-0.07]) peritonitis. Odds of cure were higher with automated PD versus continuous ambulatory PD (AOR, 1.36 [95% CI, 1.02-1.82]), facility icodextrin use (AOR per 10% greater icodextrin use, 1.06 [95% CI, 1.01-1.12]), empirical aminoglycoside use (AOR, 3.95 [95% CI, 1.23-12.68]), and ciprofloxacin use versus ceftazidime use for Gram-negative peritonitis (AOR, 5.73 [95% CI, 1.07-30.61]). Prior peritonitis episodes (AOR, 0.85 [95% CI, 0.74-0.99]) and concomitant exit-site infection (AOR, 0.41 [95% CI, 0.26-0.64]) were associated with a lower odds of cure. LIMITATIONS: Sample selection may be biased and generalizability may be limited. Residual confounding and confounding by indication limit inferences. Use of facility-level treatment variables may not capture patient-level treatments. CONCLUSIONS: Outcomes after peritonitis vary by patient characteristics, peritonitis characteristics, and modifiable peritonitis treatment practices. Differences in the odds of cure across infecting organisms and antibiotic regimens suggest that organism-specific treatment considerations warrant further investigation.

Humoral Response and SARS-CoV-2 Infection Risk following the Third and Fourth Doses of the BNT162b2 Vaccine in Dialysis Patients.

The optimal SARS-CoV-2 vaccination schedule in dialysis patients and the potential need for a fourth vaccine dose are debatable. We prospectively assessed the humoral responses to three and four doses of BNT162b2 among dialysis patients. The study included 106 dialysis patients; 60 (56.6%) and 46 (43.4%) received 3 and 4 vaccine doses, respectively. Anti-spike (anti-S) antibody titers significantly increased after the third vaccine dose, followed by a decline, yet still remained higher than all previous measurements. The fourth vaccine dose led to another profound rise in anti-S titers. The absolute increase following the fourth dose correlated with response to the third dose. Infection risk however was similar between patients vaccinated with three or four doses.

International peritoneal dialysis training practices and the risk of peritonitis.

BACKGROUND: The effects of training practices on outcomes of patients receiving peritoneal dialysis (PD) are poorly understood and there is a lack of evidence informing best training practices. This prospective cohort study aims to describe and compare international PD training practices and their association with peritonitis. METHODS: Adult patients on PD <3 months participating in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) were included. Training characteristics (including duration, location, nurse affiliation, modality, training of family members, use of individual/group training and use of written/oral competency assessments) were reported at patient and facility levels. The hazard ratio (HR) for time to first peritonitis was estimated using Cox models, adjusted for selected patient and facility case-mix variables. RESULTS: A total of 1376 PD patients from 120 facilities across seven countries were included. Training was most commonly performed at the facility (81%) by facility-affiliated nurses (87%) in a 1:1 setting (79%). In the UK, being trained by both facility and third-party nurses was associated with a reduced peritonitis risk [adjusted HR 0.31 (95% confidence interval 0.15-0.62) versus facility nurses only]. However, this training practice was utilized in only 5 of 14 UK facilities. No other training characteristics were convincingly associated with peritonitis risk. CONCLUSIONS: There was no evidence to support that peritonitis risk was associated with when, where, how or how long PD patients are trained.

Differences in mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech) SARS-CoV-2 vaccine immunogenicity among patients undergoing dialysis.

BACKGROUND: Differences in immunogenicity between mRNA SARS-CoV-2 vaccines have not been well characterized in patients undergoing dialysis. We compared the serologic response in patients undergoing maintenance hemodialysis after vaccination against SARS-CoV-2 with BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna). METHODS: We conducted a prospective observational cohort study at 2 academic centres in Toronto, Canada, from Feb. 2, 2021, to July 20, 2021, which included 129 and 95 patients who received the BNT162b2 and mRNA-1273 SARS-CoV-2 vaccines, respectively. We measured SARS-CoV-2 immunoglobulin G antibodies to the spike protein (anti-spike), receptor binding domain (anti-RBD) and nucleocapsid protein (anti-NP) at 6-7 and 12 weeks after the second dose of vaccine and compared those levels with the median convalescent serum antibody levels from 211 controls who were previously infected with SARS-CoV-2. RESULTS: At 6-7 weeks after 2-dose vaccination, we found that 51 of 70 patients (73%) who received BNT162b2 and 83 of 87 (95%) who received mRNA-1273 attained convalescent levels of anti-spike antibody (p < 0.001). In those who received BNT162b2, 35 of 70 (50%) reached the convalescent level for anti-RBD compared with 69 of 87 (79%) who received mRNA-1273 (p < 0.001). At 12 weeks after the second dose, anti-spike and anti-RBD levels were significantly lower in patients who received BNT162b2 than in those who received mRNA-1273. For anti-spike, 70 of 122 patients (57.4%) who received BNT162b2 maintained the convalescent level versus 68 of 71 (96%) of those who received mRNA-1273 (p < 0.001). For anti-RBD, 47 of 122 patients (38.5%) who received BNT162b2 maintained the anti-RBD convalescent level versus 45 of 71 (63%) of those who received mRNA-1273 (p = 0.002). INTERPRETATION: In patients undergoing hemodialysis, mRNA-1273 elicited a stronger humoral response than BNT162b2. Given the rapid decline in immunogenicity at 12 weeks in patients who received BNT162b2, a third dose is recommended in patients undergoing dialysis as a primary series, similar to recommendations for other vulnerable populations.

Spiritual well-being and its relationship with patient characteristics and other patient-reported outcomes in peritoneal dialysis patients: Findings from the PDOPPS.

BACKGROUND: Spiritual well-being (SWB), an individual's understanding of the meaning and purpose of life, may help patients with chronic or terminal illnesses cope with their diseases. This study aimed to assess SWB in patients on peritoneal dialysis (PD), as well as its relationship with patient characteristics and patient-reported outcomes (PRO). METHODS: The data were obtained from questionnaires that formed part of the PD Outcomes and Practice Patterns Study (PDOPPS). Measures used in this study were SWB scores derived from the WHO quality of life, spirituality, religiousness and personal beliefs (WHOQOL-SRPB) tool including 32 items from eight facets; physical (PCS) and mental component summary (MCS) scores of the 12-Item Short-Form Health Survey (SF-12), Center of Epidemiologic Studies Depression Scale-10 (CES-D-10) scores, burden of kidney disease scores and functional status scores. RESULTS: Overall, 529 out of 848 participants (62%) completely responded to the questionnaires and were included in the analysis. Over two-thirds of PD patients (70%) had moderate or higher SWB scores. The SWB scores were significantly lower in patients with age >65 years and unemployed status. SWB scores positively correlated with higher PCS, MCS, burden of kidney disease scores and functional status scores, while negatively correlated with depression scores by CES-D-10 scale. Patients who reported significant depressive symptoms (CES-D-10 score ≥ 10) had significantly lower SWB scores. CONCLUSION: Better SWB was significantly associated with better health-related QOL (HRQOL) and the absence of depressive symptoms. SWB may be an essential consideration in the delivery of high-quality PD.

A genome-wide association study suggests correlations of common genetic variants with peritoneal solute transfer rates in patients with kidney failure receiving peritoneal dialysis.

Movement of solutes across the peritoneum allows for the use of peritoneal dialysis to treat kidney failure. However, there is a large inter-individual variability in the peritoneal solute transfer rate (PSTR). Here, we tested the hypothesis that common genetic variants are associated with variability in PSTR. Of the 3561 participants from 69 centers in six countries, 2850 with complete data were included in a genome-wide association study. PSTR was defined as the four-hour dialysate/plasma creatinine ratio from the first peritoneal equilibration test after starting PD. Heritability of PSTR was estimated using genomic-restricted maximum-likelihood analysis, and the association of PSTR with a genome-wide polygenic risk score was also tested. The mean four-hour dialysate/plasma creatinine ratio in participants was 0.70. In 2212 participants of European ancestry, no signal reached genome-wide significance but 23 single nucleotide variants at four loci demonstrated suggestive associations with PSTR. Meta-analysis of ancestry-stratified regressions in 2850 participants revealed five single-nucleotide variants at four loci with suggestive correlations with PSTR. Association across ancestry strata was consistent for rs28644184 at the KDM2B locus. The estimated heritability of PSTR was 19%, and a permuted model polygenic risk score was significantly associated with PSTR. Thus, this genome-wide association study of patients receiving peritoneal dialysis bolsters evidence for a genetic contribution to inter-individual variability in PSTR.

Burden of Kidney Disease, Health-Related Quality of Life, and Employment Among Patients Receiving Peritoneal Dialysis and In-Center Hemodialysis: Findings From the DOPPS Program.

RATIONALE & OBJECTIVE: Individuals faced with decisions regarding kidney replacement therapy options need information on how dialysis treatments might affect daily activities and quality of life, and what factors might influence the evolution over time of the impact of dialysis on daily activities and quality of life. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: 7,771 hemodialysis (HD) and peritoneal dialysis (PD) participants from 6 countries participating in the Peritoneal and Dialysis Outcomes and Practice Patterns Studies (PDOPPS/DOPPS). PREDICTORS: Patient-reported functional status (based on daily living activities), country, demographic and clinical characteristics, and comorbidities. OUTCOME: Employment status and patient-reported outcomes (PROs) including Kidney Disease Quality of Life (KDQOL) instrument physical and mental component summary scores (PCS, MCS), kidney disease burden score, and depression symptoms (Center for Epidemiologic Studies Depression Scale [CES-D] score > 10). ANALYTICAL APPROACH: Linear regression (PCS, MCS, kidney disease burden score), logistic regression (depression symptoms), adjusted for predictors plus 12 additional comorbidities. RESULTS: In both dialysis modalities, patients in Japan had the highest PCS and employment (55% for HD and 68% for PD), whereas those in the United States had the highest MCS score, lowest kidney disease burden, and lowest employment (20% in HD and 42% in PD). After covariate adjustment, the association of age, sex, dialysis vintage, diabetes, and functional status with PROs was similar in both modalities, with women having lower PCS and kidney disease burden scores. Lower functional status (score <11) was strongly associated with lower PCS and MCS scores, a much greater burden of kidney disease, and greater likelihood of depression symptoms (CES-D, >10). The median change in KDQOL-based PROs was negligible over 1 year in participants who completed at least 2 annual questionnaires. LIMITATIONS: Selection bias due to incomplete survey responses. Generalizability was limited to the dialysis populations of the included countries. CONCLUSIONS: Variation exists in quality of life, burden of kidney disease, and depression across countries but did not appreciably change over time. Functional status remained one of the strongest predictors of all PROs. Routine assessment of functional status may provide valuable insights for patients and providers in anticipating outcomes and support needs for patients receiving either PD or HD.

Telehealth for Home Dialysis in COVID-19 and Beyond: A Perspective From the American Society of Nephrology COVID-19 Home Dialysis Subcommittee.

The coronavirus disease 2019 (COVID-19) pandemic, technological advancements, regulatory waivers, and user acceptance have converged to boost telehealth activities. Due to the state of emergency, regulatory waivers in the United States have made it possible for providers to deliver and bill for services across state lines for new and established patients through Health Insurance Portability and Accountability Act (HIPAA)- and non-HIPAA-compliant platforms with home as the originating site and without geographic restrictions. Platforms have been developed or purchased to perform videoconferencing, and interdisciplinary dialysis teams have adapted to perform virtual visits. Telehealth experiences and challenges encountered by dialysis providers, clinicians, nurses, and patients have exposed health care disparities in areas such as access to care, bandwidth connectivity, availability of devices to perform telehealth, and socioeconomic and language barriers. Future directions in telehealth use, quality measures, and research in telehealth use need to be explored. Telehealth during the public health emergency has changed the practice of health care, with the post-COVID-19 world unlikely to resemble the prior era. The future impact of telehealth in patient care in the United States remains to be seen, especially in the context of the Advancing American Kidney Health Initiative.

Hemodialysis Use and Practice Patterns: An International Survey Study.

RATIONALE & OBJECTIVE: Hemodialysis (HD) is the most common form of kidney replacement therapy. This study aimed to examine the use, availability, accessibility, affordability, and quality of HD care worldwide. STUDY DESIGN: A cross-sectional survey. SETTING & PARTICIPANTS: Stakeholders (clinicians, policy makers, and consumer representatives) in 182 countries were convened by the International Society of Nephrology from July to September 2018. OUTCOMES: Use, availability, accessibility, affordability, and quality of HD care. ANALYTICAL APPROACH: Descriptive statistics. RESULTS: Overall, representatives from 160 (88%) countries participated. Median country-specific use of maintenance HD was 298.4 (IQR, 80.5-599.4) per million population (pmp). Global median HD use among incident patients with kidney failure was 98.0 (IQR, 81.5-140.8) pmp and median number of HD centers was 4.5 (IQR, 1.2-9.9) pmp. Adequate HD services (3-4 hours 3 times weekly) were generally available in 27% of low-income countries. Home HD was generally available in 36% of high-income countries. 32% of countries performed monitoring of patient-reported outcomes; 61%, monitoring of small-solute clearance; 60%, monitoring of bone mineral markers; 51%, monitoring of technique survival; and 60%, monitoring of patient survival. At initiation of maintenance dialysis, only 5% of countries used an arteriovenous access in almost all patients. Vascular access education was suboptimal, funding for vascular access procedures was not uniform, and copayments were greater in countries with lower levels of income. Patients in 23% of the low-income countries had to pay >75% of HD costs compared with patients in only 4% of high-income countries. LIMITATIONS: A cross-sectional survey with possibility of response bias, social desirability bias, and limited data collection preventing in-depth analysis. CONCLUSIONS: In summary, findings reveal substantial variations in global HD use, availability, accessibility, quality, and affordability worldwide, with the lowest use evident in low- and lower-middle-income countries.