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Rationale & Objective: Clinical guidelines define chronic kidney disease (CKD) as abnormalities of kidney structure or function for>3 months. Assessment of the duration criterion may be implemented in different ways, potentially impacting estimates of disease incidence or prevalence in the population, individual diagnosis, and treatment decisions, especially for more severe cases. We investigated differences in incidence and prognosis of CKD stage G4 identified by 1 of 4 algorithms., Study Design: Population-based cohort study in Alberta, Canada., Setting & Participants: Residents>18 years old with incident CKD stage G4 (eGFR 15-29mL/min/1.73m 2 ) diagnosed between April 1, 2015, and March 31, 2018, based on administrative and laboratory data., Exposure: Four outpatient eGFR-based algorithms, increasing in stringency, for defining cohorts with CKD G4 were evaluated: (1) a single test, (2) first eGFR<30mL/min/1.73m 2 and a second eGFR 15-29mL/min/1.73m 2 measured>90 days apart (2 tests), (3) ≥2 eGFR measurements of<30mL/min/1.73m 2 sustained for>90 days (qualifying period) and the last eGFR in the qualifying period of 15-29mL/min/1.73m 2 (relaxed sustained), and (4) ≥2 consecutive measurements of 15-29mL/min/1.73m 2 for>90 days (rigorous sustained)., Outcome: Time to the earliest of death, eGFR improvement (a sustained increase in eGFR to≥30mL/min/1.73m 2 for>90 days and>25% increase from the index eGFR), or kidney failure., Analytical Approach: For each of the 4 cohorts, incidence rates and event-specific cumulative incidence functions at 1 year from cohort entry were estimated., Results: The incidence rates of CKD G4 decreased as algorithms became more stringent, from 190.7 (single test) to 79.9 (rigorous sustained) per 100,000 person-years. The 2 cohorts based on sustained reductions in eGFR were of comparable size and 1-year event-specific probabilities. The 2 cohorts based on a single test and a 2-test sequence were larger and experienced higher probabilities of eGFR improvement., Limitations: A short follow-up period of 1 year and a predominantly White population., Conclusions: The use of more stringent algorithms for defining CKD G4 results in substantially lower estimates of disease incidence, the identification of a group with a lower probability of eGFR improvement, and a higher risk of kidney failure. These findings can inform implementation decisions of disease definitions in clinical reporting systems and research studies., Plain-Language Summary: Although guidelines recommend>3 months to define chronic kidney disease (CKD), the methods for defining specific stages, particularly G4 (eGFR 15-29mL/min/1.73m 2 ) when referral to nephrology services is recommended, have been implemented differently across studies and surveillance programs. We studied differences in incidence and prognosis of CKD G4 cohorts identified by 4 algorithms using administrative and outpatient laboratory databases in Alberta, Canada. We found that, compared with a single-test definition, more stringent definitions resulted in a lower disease incidence and identified a group with worse short-term kidney outcomes. These findings highlight the impact of the choice of algorithm used to define CKD G4 on disease burden estimates at the population level, on individual prognosis, and on treatment/referral decisions., (Copyright © 2023 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Survivors of acute kidney injury (AKI) are at high risk of adverse outcomes. Monitoring of kidney function, screening for proteinuria, use of statins and renin-angiotensin-aldosterone system (RAAS) inhibitors, and nephrology follow-up among survivors have not been fully characterized. We examined these processes of care after discharge in survivors of hospitalized AKI., Study Design: Population-based retrospective cohort study., Setting & Participants: Adults in Alberta, Canada, admitted to the hospital between 2009 and 2017, then followed from their discharge date until 2019 for a median follow-up of 2.7 years., Exposure: Hospital-acquired AKI diagnostically conforming to Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria for stage 2 or stage 3 disease, or the need for acute dialysis., Outcome: Outcomes after hospital discharge included the proportion of participants who had evaluation of kidney function, were seen by a specialist or general practitioner, and received postdischarge prescriptions for recommended medications for chronic kidney disease (CKD)., Analytical Approach: Cumulative incidence curves to characterize the proportion of participants who received each process of care outcome within the first 90 days and subsequent 1-year follow-up period after hospital discharge. To avoid risks associated with multiple hypothesis testing, differences were not statistically compared across groups., Results: The cohort (n=23,921) included 50.2% men (n=12,015) with a median age of 68.1 [IQR, 56.9-78.8] years. Within 90 days after discharge, 21.2% and 8.6% of patients with and without pre-existing CKD, respectively, were seen by a nephrologist; 60.1% of AKI survivors had at least 1 serum creatinine measured, but only 25.5% had an assessment for albuminuria within 90 days after discharge; 52.7% of AKI survivors with pre-existing CKD, and 51.6% with de novo CKD were prescribed a RAAS inhibitor within 4-15 months after discharge., Limitations: Retrospective data were collected as part of routine clinical care., Conclusions: The proportion of patients receiving optimal care after an episode of AKI in Alberta was low and may represent a target for improving long-term outcomes for this population., Plain-Language Summary: A study in Alberta, Canada, examined the care received by patients with acute kidney disease (AKI) during hospitalization and after discharge between 2007 and 2019. The results showed that a low proportion of patients with moderate to severe AKI were seen by a kidney specialist during hospitalization or within 90 days after discharge. Fewer than 25% of AKI patients had their kidney function monitored with both blood and urine tests within 90 days of discharge. Additionally, about half of AKI survivors with chronic kidney disease (CKD) were prescribed guideline recommended medications for CKD within 15 months after discharge. There is potential to improve health care delivery to these patients both in hospital and after hospital discharge., (Copyright © 2023 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Sick day medication guidance (SDMG) involves withholding or adjusting specific medications in the setting of acute illnesses that could contribute to complications such as hypotension, acute kidney injury (AKI), or hypoglycemia. We sought to achieve consensus among clinical experts on recommendations for SDMG that could be studied in future intervention studies., Study Design: A modified Delphi process following guidelines for conducting and reporting Delphi studies., Setting & Participants: An international group of clinicians with expertise relevant to SDMG was recruited through purposive and snowball sampling. A scoping review of the literature was presented, followed by 3 sequential rounds of development, refinement, and voting on recommendations. Meetings were held virtually and structured to allow the participants to provide their input and rapidly prioritize and refine ideas., Outcome: Opinions of participants were measured as the percentage who agreed with each recommendation, whereas consensus was defined as >75% agreement., Analytical Approach: Quantitative data were summarized using counts and percentages. A qualitative content analysis was performed to capture the context of the discussion around recommendations and any additional considerations brought forward by participants., Results: The final panel included 26 clinician participants from 4 countries and 10 clinical disciplines. Participants reached a consensus on 42 specific recommendations: 5 regarding the signs and symptoms accompanying volume depletion that should trigger SDMG; 6 regarding signs that should prompt urgent contact with a health care provider (including a reduced level of consciousness, severe vomiting, low blood pressure, presence of ketones, tachycardia, and fever); and 14 related to scenarios and strategies for patient self-management (including frequent glucose monitoring, checking ketones, fluid intake, and consumption of food to prevent hypoglycemia). There was consensus that renin-angiotensin system inhibitors, diuretics, nonsteroidal anti-inflammatory drugs, sodium/glucose cotransporter 2 inhibitors, and metformin should be temporarily stopped. Participants recommended that insulin, sulfonylureas, and meglitinides be held only if blood glucose was low and that basal and bolus insulin be increased by 10%-20% if blood glucose was elevated. There was consensus on 6 recommendations related to the resumption of medications within 24-48 hours of the resolution of symptoms and the presence of normal patterns of eating and drinking., Limitations: Participants were from high-income countries, predominantly Canada. Findings may not be generalizable to implementation in other settings., Conclusions: A multidisciplinary panel of clinicians reached a consensus on recommendations for SDMG in the presence of signs and symptoms of volume depletion, as well as self-management strategies and medication instructions in this setting. These recommendations may inform the design of future trials of SDMG strategies., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Collaborative approaches to vascular access selection are being increasingly encouraged to elicit patients' preferences and priorities where no unequivocally superior choice exists. We explored how patients, their caregivers, and clinicians integrate principles of shared decision making when engaging in vascular access discussions., Study Design: Qualitative description., Setting & Participants: Semistructured interviews with a purposive sample of patients, their caregivers, and clinicians from outpatient hemodialysis programs in Alberta, Canada., Analytical Approach: We used a thematic analysis approach to inductively code transcripts and generate themes to capture key concepts related to vascular access shared decision making across participant roles., Results: 42 individuals (19 patients, 2 caregivers, 21 clinicians) participated in this study. Participants identified how access-related decisions follow a series of major decisions about kidney replacement therapy and care goals that influence vascular access preferences and choice. Vascular access shared decision making was strengthened through integration of vascular access selection with dialysis-related decisions and timely, tailored, and balanced exchange of information between patients and their care team. Participants described how opportunities to revisit the vascular access decision before and after dialysis initiation helped prepare patients for their access and encouraged ongoing alignment between patients' care priorities and treatment plans. Where shared decision making was undermined, hemodialysis via a catheter ensued as the most readily available vascular access option., Limitations: Our study was limited to patients and clinicians from hemodialysis care settings and included few caregiver participants., Conclusions: Findings suggest that earlier, or upstream, decisions about kidney replacement therapies influence how and when vascular access decisions are made. Repeated vascular access discussions that are integrated with other higher-level decisions are needed to promote vascular access shared decision making and preparedness., (Copyright © 2022 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: The KDIGO (Kidney Disease: Improving Global Outcomes) definition of acute kidney injury (AKI) is frequently used in studies to examine the epidemiology of AKI. This definition is variably interpreted and applied to routinely collected health care data. The aim of this study was to examine this variation and to achieve consensus in how AKI should be defined for research using routinely collected health care data., Sources of Evidence and Study Design: Scoping review via searching Medline and EMBASE for studies using health care data to examine AKI by using the KDIGO creatinine-based definition. An international panel of experts formed to participate in a modified Delphi process to attempt to generate consensus about how AKI should be defined when using routinely collected laboratory data., Charting Methods and Analytical Approach: The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) extension for scoping reviews was followed. For the Delphi process, 2 rounds of questions were distributed via internet-based questionnaires to all participants with a prespecified cutoff of 75% agreement used to define consensus., Results: The scoping review found 174 studies that met the inclusion criteria. The KDIGO definition was inconsistently applied, and the methods for application were poorly described. We found 58 (33%) of papers did not provide a definition of how the baseline creatinine value was determined, and only 34 (20%) defined recovery of kidney function. Of 55 invitees to the Delphi process, 35 respondents participated in round 1, and 25 participated in round 2. Some consensus was achieved in areas related to how to define the baseline creatinine value, which patients should be excluded from analysis of routinely collected laboratory data, and how persistent chronic kidney disease or nonrecovery of AKI should be defined., Limitations: The Delphi panel members predominantly came from the United Kingdom, the United States, and Canada, and there were low response rates for some questions in round 1., Conclusions: The current methods for defining AKI using routinely collected data are inconsistent and poorly described in the available literature. Experts could not achieve consensus for many aspects of defining AKI and describing its sequelae. The KDIGO guidelines should be extended to include a standardized definition for how AKI should be defined when using routinely collected data., (Copyright © 2021 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: There is limited evidence to guide follow-up after acute kidney injury (AKI). Knowledge gaps include which patients to prioritize, at what time point, and for mitigation of which outcomes. In this study, we sought to compare the net benefit of risk model-based clinical decisions following AKI., Study Design: External validation of 2 risk models of AKI outcomes: the Grampian -Aberdeen (United Kingdom) AKI readmissions model and the Alberta (Canada) kidney disease risk model of chronic kidney disease (CKD) glomerular (G) filtration rate categories 4 and 5 (CKD G4 and G5). Process mining to delineate existing care pathways., Setting & Participants: Validation was based on data from adult hospital survivors of AKI from Grampian, 2011-2013., Predictors: KDIGO-based measures of AKI severity and comorbidities specified in the original models., Outcomes: Death or readmission within 90 days for all hospital survivors. Progression to new CKD G4-G5 for patients surviving at least 90 days after AKI., Analytical Approach: Decision curve analysis to assess the "net benefit" of use of risk models to guide clinical care compared to alternative approaches (eg, prioritizing all AKI, severe AKI, or only those without kidney recovery)., Results: 26,575 of 105,461 hospital survivors in Grampian (mean age, 60.9 ± 19.8 [SD] years) were included for validation of the death or readmission model, and 9,382 patients (mean age, 60.9 ± 19.8 years) for the CKD G4-G5 model. Both models discriminated well (area under the curve [AUC], 0.77 and 0.86, respectively). Decision curve analysis showed greater net benefit for follow up of all AKI than only severe AKI in most cases. Both original and refitted models provided net benefit superior to any other decision strategy. In process mining of all hospital discharges, 41% of readmissions and deaths occurred among people recovering after AKI. 1,464 of 3,776 people (39%) readmitted after AKI had received no intervening monitoring., Limitations: Both original models overstated risks, indicating a need for regular updating., Conclusions: Follow up after AKI has potential net benefit for preempting readmissions, death, and subsequent CKD progression. Decisions could be improved by using risk models and by focusing on AKI across a full spectrum of severity. The current lack of monitoring among many with poor outcomes indicates possible opportunities for implementation of decision support., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Kidney disease is associated with an increased risk for postoperative morbidity and mortality. However, the incidence of major surgery on a population level is unknown. We aimed to determine the incidence of major surgery by level of kidney function., Study Design: Retrospective cohort study with entry from January 1, 2008, through December 31, 2009, and outcome surveillance from January 1, 2010, through December 31, 2016., Setting & Participants: Population-based study using administrative health data from Alberta, Canada; adults with an outpatient serum creatinine measurement or receiving maintenance dialysis formed the study cohort., Exposure: Participants were categorized into 6 estimated glomerular filtration rate (eGFR) categories: ≥60 (G1-G2), 45 to 59 (G3a), 30 to 44 (G3b), 15 to 29 (G4), and<15mL/min/1.73m 2 with (G5D) and without (G5) dialysis. eGFR was examined as a time-varying exposure based on means of measurements within 3-month ascertainment periods throughout the study period., Outcome: Major surgery defined as surgery requiring admission to the hospital for at least 24 hours., Analytical Approach: Incidence rates (IRs) for overall major surgery were estimated using quasi-Poisson regression and adjusted for age, sex, income, location of residence, albuminuria, and Charlson comorbid conditions. Age- and sex-stratified IRs of 13 surgery subtypes were also estimated., Results: 1,455,512 cohort participants were followed up for a median of 7.0 (IQR, 5.3) years, during which time 241,989 (16.6%) underwent a major surgery. Age and sex modified the relationship between eGFR and incidence of surgery. Men younger than 65 years receiving maintenance dialysis experienced the highest rates of major surgery, with an adjusted IR of 243.8 (95% CI, 179.8-330.6) per 1,000 person-years. There was a consistent trend of increasing surgery rates at lower eGFRs for most subtypes of surgery., Limitations: Outpatient preoperative serum creatinine measurement was necessary for inclusion and outpatient surgical procedures were not included., Conclusions: People with reduced eGFR have a significantly higher incidence of major surgery compared with those with normal eGFR, and age and sex modify this increased risk. This study informs our understanding of how surgical burden changes with differing levels of kidney function., (Copyright © 2020 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Use of brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) for cardiovascular (CV) risk assessment in patients with end-stage kidney disease (ESKD) remains unclear. We examined the associations between different threshold elevations of these peptide levels and clinical outcomes in patients with ESKD., Study Design: Systematic review and meta-analysis., Setting & Study Populations: We searched MEDLINE and EMBASE (through September 2019) for observational studies of adults with ESKD (estimated glomerular filtration rate≤15mL/min/1.73m 2 or receiving maintenance dialysis)., Selection Criteria for Studies: Studies that reported NT-proBNP or BNP levels and future CV events, CV mortality, or all-cause mortality., Data Extraction: Cohort characteristics and measures of risk associated with study-specified peptide thresholds., Analytical Approach: Hazard ratios (HRs) for clinical outcomes associated with different NT-proBNP and BNP ranges were categorized into common thresholds and pooled using random-effects meta-analysis., Results: We identified 61 studies for inclusion in our review (19,688 people). 49 provided sufficient detail for inclusion in meta-analysis. Pooled unadjusted HRs for CV mortality were progressively greater for greater thresholds of NT-proBNP, from 1.45 (95% CI, 0.91-2.32) for levels>2,000pg/mL to 5.95 (95% CI, 4.23-8.37) for levels>15,000pg/mL. Risk for all-cause mortality was significantly higher at all NT-proBNP thresholds ranging from> 1,000 to> 20,000pg/mL (HR range, 1.53-4.00). BNP levels>550pg/mL were associated with increased risk for CV mortality (HR, 2.54; 95% CI, 1.49-4.33), while the risks for all-cause mortality were 2.04 (95% CI, 0.82-5.12) at BNP levels>100pg/mL and 2.97 (95% CI, 2.21-3.98) at BNP levels>550pg/mL. Adjusted analyses demonstrated similarly greater risks for CV and all-cause mortality with greater NT-proBNP concentrations., Limitations: Incomplete outcome reporting and risk for outcome reporting bias. Estimation of risk for CV events for specific thresholds of both peptides were limited by poor precision., Conclusions: ESKD-specific NT-proBNP and BNP level thresholds of elevation are associated with increased risk for CV and all-cause mortality. This information may help guide interpretation of NT-proBNP and BNP levels in patients with ESKD., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Fostering the ability of patients to self-manage their chronic kidney disease (CKD), with support from caregivers and providers, may slow disease progression and improve health outcomes. However, little is known about such patients' needs for self-management interventions. We aimed to identify and describe the needs of adults with CKD and informal caregivers for CKD self-management support., Study Design: Descriptive qualitative study using semi-structured interviews and focus groups., Setting & Participants: 6 focus groups (37 participants) and 11 telephone interviews with adults with CKD (stages 1-5, not on renal replacement therapy) and informal caregivers from across Canada., Analytic Approach: Thematic analysis., Results: 3 major themes were identified: (1) empowerment through knowledge (awareness and understanding of CKD, diet challenges, medication and alternative treatments, attuning to the body, financial implications, mental and physical health consequences, travel and transportation restrictions, and maintaining work and education), (2) activation through information sharing (access, meaningful and relevant, timing, and amount), and (3) tangible supports for the health journey (family, community, and professionals)., Limitations: Participants were primarily white, educated, married, and English speaking, which limits generalizability., Conclusions: There are opportunities to enhance CKD self-management support by addressing knowledge pertinent to living well with CKD and priority areas for sharing information and providing tangible support. Future efforts may consider the development of innovative CKD self-management support interventions based on the diverse patient and caregiver needs identified in this study., (Copyright © 2019 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Rationale & Objective: Conservative kidney management is holistic patient-centered care for patients with kidney failure that focuses on delaying the progression of kidney disease and symptom management, without the provision of renal replacement therapy. Currently there is no consensus as to what constitutes high-quality conservative kidney management. We aimed to develop a set of quality indicators for the conservative management of kidney failure., Study Design: Nominal group technique and Delphi survey process., Setting & Participants: 16 patients and caregivers from Calgary, Canada, participated in 2 nominal group meetings. 91 multidisciplinary health care professionals from 10 countries took part in a Delphi process., Analytical Approach: Nominal group technique study of patients and caregivers was used to identify and prioritize a list of quality indicators. A 4-round Delphi process with health care professionals was used to rate the quality indicators until consensus was reached (defined as a mean rating on the Likert scale ≥7.0 and percent agreement >75%). Quality indicators that met criteria for consensus inclusion in the Delphi survey were ranked, and comparisons were made with nominal group priorities., Results: 99 quality indicators met consensus criteria for inclusion. The most highly rated quality indicator in the Delphi process was the "percentage of patients that die in the place they desire." There was significant discordance between priorities of the nominal groups with that of the Delphi survey, with only 1 quality indicator being shared on each groups' top 10 list of quality indicators., Limitations: Participants were largely from high-income English-speaking countries, and most already had structured conservative kidney management programs in place, all potentially limiting generalizability., Conclusions: Quality of conservative kidney management care is important to patients, caregivers, and health care professionals. However, discordant quality indicator priorities between groups suggested that care providers delivering conservative kidney management may not prioritize what is most important to those receiving this care. Conservative kidney management programs and health care providers can improve the applicability of this consensus-based quality indicator list to their program by further developing and evaluating it for use in their program., (Copyright © 2018 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Caring for patients with end-stage renal disease (ESRD) requiring dialysis is intensive and expensive. Telehealth may improve the access and efficiency of ESRD care. For this perspective, we systematically reviewed studies that examined the effectiveness of telehealth versus or in addition to usual care for ESRD management. 10 studies were identified, including 7 randomized trials and 3 cohort studies. Study populations, modes of delivery (including telephone, telemetry, or videoconferencing), and the outcomes evaluated varied substantially between studies. Two studies examined telehealth interventions versus standard ESRD care and demonstrated mixed results on processes of care, no differences in laboratory surrogate markers of ESRD care, and reduced or similar rates of hospitalization. Eight studies evaluated the addition of telehealth to usual care and demonstrated no significant improvements in processes of care or surrogate laboratory measures, variable impacts on hospitalization rates, and mixed impacts on some domains of quality of life, including improvement in mental health. Although potential benefits of telehealth in ESRD care have been reported, optimal designs for delivery and elements of care that may be improved through telehealth remain uncertain., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The effectiveness and safety of warfarin use among patients with atrial fibrillation (AF) and reduced kidney function are uncertain., Study Design: Community-based retrospective cohort study (May 1, 2003, to March 31, 2012) using province-wide laboratory and administrative data in Alberta, Canada., Setting & Participants: 14,892 adults 66 years or older with new AF and a measurement of kidney function. Long-term dialysis patients or kidney transplant recipients were excluded., Predictor: Propensity scores were used to construct a matched-pairs cohort of patients with AF who did and did not have a warfarin prescription within a 60-day period surrounding their AF diagnosis., Outcomes: Within 1 year of initiating warfarin therapy (or the matched date for nonusers): (1) the composite of all-cause death, ischemic stroke, or transient ischemic attack (also assessed as separate end points) and (2) first hospitalization or emergency department visit for a major bleeding episode defined as an intracranial, upper or lower gastrointestinal, or other bleeding., Measurements: Baseline glomerular filtration rate (GFR) was estimated using the CKD-EPI creatinine equation. Patients were matched within estimated GFR (eGFR) categories: ≥90, 60 to 89, 45 to 59, 30 to 44, and <30mL/min/1.73m 2 . Information for baseline characteristics (sociodemographics, comorbid conditions, and prescription drug use) was obtained., Results: Across eGFR categories, warfarin therapy initiation was associated with lower risk for the composite outcome compared to nonuse (adjusted HRs [95% CI] for eGFR categories ≥ 90, 60-89, 45-59, 30-44, and <30mL/min/1.73m 2 : 0.59 [0.35-1.01], 0.61 [0.54-0.70], 0.55 [0.47-0.65], 0.54 [0.44-0.67], and 0.64 [0.47-0.87] mL/min/1.73m 2 , respectively). Compared to nonuse, warfarin therapy was not associated with higher risk for major bleeding except for those with eGFRs of 60 to 89mL/min/1.73m 2 (HR, 1.36; 95% CI, 1.13-1.64)., Limitations: Selection bias., Conclusions: Among older adults with AF, warfarin therapy initiation was associated with a significantly lower 1-year risk for the composite outcome across all strata of kidney function. The risk for major bleeding associated with warfarin use was increased only among those with eGFRs of 60 to 89mL/min/1.73m 2 ., (Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Educational interventions are increasingly used to promote peritoneal dialysis (PD), the most common form of home therapy for end-stage renal disease. A systematic review of the evidence in support of dialysis modality education is needed to inform the design of patient-targeted interventions to increase selection of PD. We performed a systematic review and meta-analysis to characterize the relationship between patient-targeted educational interventions and choosing and receiving PD., Study Design: Systematic review and meta-analysis., Setting & Population: Published original studies and abstracts., Selection Criteria for Studies: We searched MEDLINE, EMBASE, CINAHL and EBMR. We included controlled observational studies and randomized trials of educational interventions designed to increase PD selection., Intervention: Predialysis educational interventions., Outcomes: The primary outcome was choosing PD, defined as intention to use PD regardless of whether PD was ever used. The secondary outcome, receiving PD, was defined as an individual receiving PD as his or her treatment., Results: Of 3,540 citations, 15 studies met our inclusion criteria, including 1 randomized trial. In the single randomized trial (N=70), receipt of an educational intervention was associated with a more than 4-fold increase in the odds of choosing PD (OR, 4.60; 95% CI, 1.19-17.74). Based on results from 4 observational studies (N=7,653), patient-targeted educational interventions were associated with a 2-fold increase in the odds of choosing PD (pooled OR, 2.15; 95% CI, 1.07-4.32; I(2)=76.7%). Based on results from 9 observational studies (N=8,229), patient-targeted educational intervention was associated with a 3-fold increase in the odds of receiving PD as the initial treatment modality (OR, 3.50; 95% CI, 2.82-4.35; I(2)=24.9%)., Limitations: Most studies were observational studies, which can establish an association between education and choosing PD or receiving PD, but does not establish causality., Conclusions: This systematic review demonstrates a strong association between patient-targeted education interventions and the subsequent choice and receipt of PD., (Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Preemptive correction of a stenosis in an arteriovenous (AV) access (fistula or graft) that is adequately providing hemodialysis (functional AV access) may prolong access survival as compared to waiting for signs of access dysfunction to intervene (deferred salvage). However, the evidence in support of preemptive intervention is controversial. We evaluated benefits and harms of preemptive versus deferred correction of AV access stenosis., Study Design: Systematic review and meta-analysis of randomized controlled trials., Setting & Population: Adults receiving hemodialysis by a functional AV access., Selection Criteria for Studies: We searched the Cochrane Kidney and Transplant Specialised Register and EMBASE to October 15, 2015., Intervention: Active access surveillance (flow measurement and Doppler or venous pressure) and preemptive correction of a newly identified stenosis versus routine clinical monitoring and deferred salvage, or preemptive correction of a known stenosis versus deferred salvage., Outcomes: Access loss (primary outcome) and thrombosis (overall and by access type), infection, mortality, hospitalization, and access-related procedures., Results: We included 14 trials (1,390 participants; follow-up, 6-38 months). Relative to deferred salvage, preemptive correction of AV access stenosis had a nonsignificant effect on risk for access loss (risk ratio [RR], 0.81; 95% CI, 0.65-1.02; I(2)=0%) and a significant effect on risk for thrombosis (RR, 0.79; 95% CI, 0.65-0.97; I(2)=30%). Treatment effects were larger in fistulas than in grafts for both risk for access loss (subgroup difference, P=0.05) and risk for thrombosis (subgroup difference, P=0.002). Results were heterogeneous or imprecise for mortality, rates of access-related infections or procedures, and hospitalization., Limitations: Small number and size of primary studies limited analysis power., Conclusions: Preemptive stenosis correction in a functional AV access does not improve access longevity. Although preemptive stenosis correction may be promising in fistulas, existing evidence is insufficient to guide clinical practice and health policy., (Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Diabetes mellitus and hypertension are risk factors for acute kidney injury (AKI). Whether estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio (ACR) remain risk factors for AKI in the presence and absence of these conditions is uncertain., Study Design: Meta-analysis of cohort studies., Setting & Population: 8 general-population (1,285,045 participants) and 5 chronic kidney disease (CKD; 79,519 participants) cohorts., Selection Criteria for Studies: Cohorts participating in the CKD Prognosis Consortium., Predictors: Diabetes and hypertension status, eGFR by the 2009 CKD Epidemiology Collaboration creatinine equation, urine ACR, and interactions., Outcome: Hospitalization with AKI, using Cox proportional hazards models to estimate HRs of AKI and random-effects meta-analysis to pool results., Results: During a mean follow-up of 4 years, there were 16,480 episodes of AKI in the general-population and 2,087 episodes in the CKD cohorts. Low eGFRs and high ACRs were associated with higher risks of AKI in individuals with or without diabetes and with or without hypertension. When compared to a common reference of eGFR of 80mL/min/1.73m(2) in nondiabetic patients, HRs for AKI were generally higher in diabetic patients at any level of eGFR. The same was true for diabetic patients at all levels of ACR compared with nondiabetic patients. The risk gradient for AKI with lower eGFRs was greater in those without diabetes than with diabetes, but similar with higher ACRs in those without versus with diabetes. Those with hypertension had a higher risk of AKI at eGFRs>60mL/min/1.73m(2) than those without hypertension. However, risk gradients for AKI with both lower eGFRs and higher ACRs were greater for those without than with hypertension., Limitations: AKI identified by diagnostic code., Conclusions: Lower eGFRs and higher ACRs are associated with higher risks of AKI among individuals with or without either diabetes or hypertension., (Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Robust estimates and sources of variation in risks of clinical outcomes for cardiopulmonary bypass (CPB)-associated acute kidney injury (AKI) are needed to inform clinical practice and policy. We aimed to assess whether the methods for defining acute kidney disease modify the estimated association of AKI with CPB., Study Design: Systematic review and meta-analysis., Setting & Population: Adults undergoing CPB., Selection Criteria for Studies: Cohort studies reporting adjusted associations between CPB-associated AKI and early mortality, later mortality, stroke, myocardial infarction, congestive heart failure, all-cause hospitalization, chronic kidney disease, end-stage kidney disease, bleeding complications, or perioperative infection., Predictors: CPB-associated AKI and renal replacement therapy., Outcomes: The primary outcome was early mortality (in-hospital or within 90 days of surgery) in studies reporting adjusted associations and secondary outcomes including total and cardiovascular mortality, major adverse cardiovascular events, rehospitalization, end-stage kidney disease, bleeding, and perioperative infection., Results: 46 studies with 47 unique cohorts comprising 242,388 participants were included. The pooled rate of CPB-associated AKI was 18.2%, and of renal replacement therapy, 2.1%. CPB-associated AKI was associated with early mortality (risk ratio [RR], 4.0; 95% CI, 3.1-5.2; crude mortality with CPB-associated AKI, 4.6%; without CPB-AKI, 1.5%) with considerable heterogeneity between studies (I(2)=87%). The AKI definition did not modify prognostic estimates (P for subgroup analysis = 0.9). When heterogeneity was fully accounted for using credibility ceilings, risks of early mortality were attenuated (RR, 2.2; 95% CI, 1.8-2.8) but remained high. Renal replacement therapy also was associated with early mortality (RR, 5.3; 95% CI, 3.4-8.1). CPB-associated AKI also was associated with long-term mortality (RR, 2.0; 95% CI, 1.7-2.3) and stroke (RR, 2.2; 95% CI, 1.1-4.5). No other outcomes were reported in more than 3 studies., Limitations: Unclear attrition from follow-up in most studies and variable adjustment for confounders across studies., Conclusions: CPB-associated AKI is associated with a more than 2-fold increase in early mortality regardless of AKI definition., (Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Ambulatory care-sensitive conditions have been described as those that (if appropriately managed in an outpatient setting) generally do not require subsequent hospitalization. Our goal was to identify clinical populations of people who are at the highest risk of ambulatory care-sensitive conditions related to chronic kidney disease (CKD)., Study Design: Retrospective cohort study., Setting & Participants: 2,003,054 adults (including 238,747 adults with CKD) residing in Alberta, Canada, with at least one serum creatinine measurement between 2002 and 2009., Predictors: Estimated glomerular filtration rate and albuminuria categories, CKD status, demographics, and clinical characteristics., Outcomes: Hospitalization with heart failure, hyperkalemia, volume overload, or malignant hypertension., Measurements: We used the Alberta Kidney Disease Network database, which incorporates data from Alberta Health, the Northern and Southern Alberta Renal Programs, and clinical laboratories in Alberta., Results: During a median follow-up of 4.1 years, 43,863 participants were hospitalized for heart failure; 6,274 participants, for hyperkalemia; 2,035 participants, for volume overload; and 481 participants, for malignant hypertension. All 4 conditions were more common at lower estimated glomerular filtration rates and in the presence of albuminuria. In the subset of participants with CKD, heart failure, hyperkalemia, and volume overload were associated most strongly with older age, diabetes, chronic liver disease, and prior heart failure. Malignant hypertension was associated with prior hypertension, aboriginal status, and peripheral vascular disease. Remote-dwelling participants were more likely to experience heart failure and malignant hypertension than those living closer to providers., Limitations: No data for medication use or potentially important process-based outcomes for study participants., Conclusions: Our findings suggest that future studies seeking to determine how to prevent ambulatory care-sensitive conditions in people with CKD should target remote dwellers and those with comorbid conditions such as concomitant heart failure and liver disease., (Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Ascorbic acid is believed to improve anemia in patients with end-stage renal disease, but its overall effectiveness is unclear., Study Design: Systematic review and meta-analysis., Setting & Population: Adult hemodialysis patients., Selection Criteria for Studies: Randomized clinical trials of ascorbic acid use in addition to standard anemia management., Intervention: Ascorbic acid., Outcomes: Weighted mean difference (WMD) for change in hemoglobin level, recombinant human erythropoietin (rHuEPO) dose, transferrin saturation and ferritin level and adverse events., Results: Of 157 potentially relevant studies, 6 studies (n = 326 patients) met the inclusion criteria. Combining the 3 randomized clinical trials involving patients with baseline hemoglobin levels <11 g/dL, change in hemoglobin level was greater for ascorbic acid use compared with standard care (WMD, 0.9 g/dL; 95% CI, 0.5-1.2 g/dL). Compared with standard care, ascorbic acid use also was associated with a statistically significant decrease in rHuEPO dose (WMD, -17.1 U/kg/wk; 95% CI, -26.0 to -8.2 U/kg/wk) and improvement in transferrin saturation (WMD, 7.9%; 95% CI, 5.2-10.5%), with no change in ferritin concentration. Adverse events had questionable relevance to ascorbic acid use; no study reported oxalate levels or occurrence of oxalosis., Limitations: Small number of studies, heterogeneity between study populations, and study durations were short. Adverse events were poorly reported., Conclusions: Although the studies are limited by small numbers of subjects, short durations of follow-up, and variable quality, these results suggest that compared with standard care, ascorbic acid use may result in an increase in hemoglobin concentration and transferrin saturation and decrease in rHuEPO requirements. Longer term studies are required to confirm these results, provide information about adverse events, and determine whether these changes translate into improved patient outcomes and cost-effectiveness.

Background: The effects of kidney disease on the risk of hospitalization or death from specific noncardiovascular causes, including pneumonia, are unclear. The objective of this study is to determine the associations between estimated glomerular filtration rate (eGFR) and hospitalization or death with pneumonia., Study Design: Retrospective cohort study., Setting & Participants: Community-based study from a Canadian health region of 252,516 participants with 1 or more outpatient serum creatinine measurements from July 1, 2003, to June 30, 2004, who were not receiving dialysis or kidney transplantation., Predictor: eGFR calculated by using the 4-variable Modification of Diet in Renal Disease Study equation., Outcomes: Hospitalization with pneumonia or death within 30 days after pneumonia hospitalization., Measurements: Cox proportional hazards models adjusted for age, sex, socioeconomic status, and comorbidities with censoring at death, initiation of renal replacement therapy, or emigration., Results: Lower eGFR was associated with increased risk of hospitalization with pneumonia, although the magnitude of effect varied with age. The risk associated with decreased eGFR was greatest in participants 18 to 54 years old; compared with participants with an eGFR of 60 to 104 mL/min/1.73 m(2), adjusted hazard ratios for hospitalization with pneumonia were 3.23 (95% confidence interval, 2.40 to 4.36) in those with eGFR of 45 to 59 mL/min/1.73 m(2), 9.67 (95% confidence interval, 6.36 to 14.69) for eGFR of 30 to 44 mL/min/1.73 m(2), and 15.04 (95% confidence interval, 9.64 to 23.47) for eGFR less than 30 mL/min/1.73 m(2). Associations became weaker with increasing age, although the graded inverse association between lower eGFR and risk remained for older participants. An age-dependent inverse relationship also was observed between eGFR and risk of death within 30 days of hospitalization with pneumonia., Limitations: Residual confounding caused by severity of illness or unmeasured comorbidities may be present., Conclusion: The risk of hospitalization and death with pneumonia is greater at lower eGFRs, especially in younger adults. This association may contribute to excess mortality in people with chronic kidney disease.