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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.)

Background: Providing support is important to maintain a patient on peritoneal dialysis (PD), though its impact on outcomes has not been investigated thoroughly. We examined the association between having support and risk of a transfer to hemodialysis., Methods: In this retrospective observational cohort study, we used data captured in the Dialysis Measurement Analysis and Reporting system about patients who started PD in Alberta, Canada, between 1 January 2013 and 30 September 2018. Support was defined as the availability of a support person in the home who was able, willing and available to provide support for PD in the patient's residence. The outcome of interest was a transfer to hemodialysis for at least 90 days. We estimated the cumulative incidence of a transfer over time accounting for competing risks and hazard ratios to summarise the association between support and a transfer. We split follow-up time as hazard ratios varied over time., Results: Six hundred and eighty-three incident PD patients, median age 58 years ( IQR : 47-68) and 35% female, were followed for a median of 15 months. The cumulative incidence of a transfer to hemodialysis at 24 months was 26%. Having support was associated with a reduced risk of a transfer between 3 and 12 months after the start of dialysis (HR 3-12mo : 0.44; 95% CI: 0.25-0.78), but not earlier (hazard ratio (HR) <3mo : 0.96; 95% confidence interval (CI): 0.55-1.69) or later (HR >12mo : 1.19; 95% CI: 0.65-2.17)., Conclusions: A transfer to hemodialysis is common. Having a support person at home is associated with a short-term protective effect after the initiation of PD.

Albumin-to-creatinine ratio (ACR), the preferred method to quantify proteinuria, can be calculated from urine dipstick protein or protein-to-creatinine ratio (PCR). The performance of calculated vs. measured ACR in predicting kidney failure and death without kidney failure in people with chronic kidney disease (CKD) is unknown. Here, we used population-based data from Alberta, Canada, to identify adults with incident moderate-severe CKD (sustained for more than 90 days) from 2008-04-01 to 2017-03-31, who had same-day measures of ACR and urine dipstick (ACR-dipstick cohort) or PCR (ACR-PCR cohort) in the two years before cohort entry. We followed participants until 2019-03-31 and trained competing risk models of kidney failure and death without kidney failure including age, sex, estimated glomerular filtration rate, diabetes, cardiovascular disease, and either measured or calculated ACR. Model performance was tested in cohorts created using the same algorithm in Manitoba, Canada. The ACR-dipstick and ACR-PCR cohorts included 18,731 and 4,542 people (training cohorts) and 821 and 1,831 people (testing cohorts), respectively. In internal and external testing, there was closer agreement between predictions based on measured vs. PCR-calculated ACR than between those based on measured vs. dipstick-calculated ACR. The dipstick-calculated ACR had higher Brier scores than measured ACR from year three for both outcomes, indicating worsening calibration. Models including measured or calculated ACR had similar discrimination: year one-to-five area under the receiver operating characteristic curve of 83-89% for kidney failure and 69-75% for mortality. Thus, if confirmed in different ethnic groups, calculated ACR can be used for risk predictions when the measured ACR is not available. PCR-calculated ACR may have superior performance to dipstick-calculated ACR., (Copyright © 2022 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Importance: Using the same level of estimated glomerular filtration rate (eGFR) to define chronic kidney disease (CKD) regardless of patient age may classify many elderly people with a normal physiological age-related eGFR decline as having a disease., Objective: To compare the outcomes associated with CKD as defined by a fixed vs an age-adapted eGFR threshold., Design, Setting, and Participants: This population-based cohort study was conducted in Alberta, Canada and used linked administrative and laboratory data from adults with incident CKD from April 1, 2009, to March 31, 2017, defined by a sustained reduction in eGFR for longer than 3 months below a fixed or an age-adapted eGFR threshold. Non-CKD controls were defined as being 65 years or older with a sustained eGFR of 60 to 89 mL/min/1.73 m2 for longer than 3 months and normal/mild albuminuria. The follow-up ended on March 31, 2019. The data were analyzed from February to April 2020., Exposures: A fixed eGFR threshold of 60 vs thresholds of 75, 60, and 45 mL/min/1.73 m2 for age younger than 40, 40 to 64, and 65 years or older, respectively., Main Outcomes and Measures: Competing risks of kidney failure (kidney replacement initiation or sustained eGFR <15 mL/min/1.73 m2 for >3 months) and death without kidney failure., Results: The fixed and age-adapted CKD cohorts included 127 132 (69 546 women [54.7%], 57 586 men [45.3%]) and 81 209 adults (44 582 women [54.9%], 36 627 men [45.1%]), respectively (537 vs 343 new cases per 100 000 person-years). The fixed-threshold cohort had lower risks of kidney failure (1.7% vs 3.0% at 5 years) and death (21.9% vs 25.4%) than the age-adapted cohort. A total of 53 906 adults were included in both cohorts. Of the individuals included in the fixed-threshold cohort only (n = 72 703), 54 342 (75%) were 65 years or older and had baseline eGFR of 45 to 59 mL/min/1.73 m2 with normal/mild albuminuria. The 5-year risks of kidney failure and death among these elderly people were similar to those of non-CKD controls, with a risk of kidney failure of 0.12% or less in both groups across all age categories and a risk of death at 69, 122, 279, and 935 times higher than the risk of kidney failure for 65 to 69, 70 to 74, 75 to 79, and 80 years or older, respectively., Conclusions and Relevance: This cohort study of adults with CKD suggests that the current criteria for CKD that use the same eGFR threshold for all ages may result in overestimation of the CKD burden in an aging population, overdiagnosis, and unnecessary interventions in many elderly people who have age-related loss of eGFR.

Background: Guidelines recommend that non-steroidal anti-inflammatory drugs (NSAIDs) be avoided in kidney transplant recipients due to potential nephrotoxicity. It is unclear whether physicians are following these recommendations., Methods: We conducted a retrospective cohort study of adult kidney transplant recipients from 2008 to 2017 in Alberta, Canada. We determined the frequency and prescriber of NSAID prescriptions, the proportion with serum creatinine and potassium testing post-fill, and the incidence of acute kidney injury (AKI, serum creatinine increase of ≥ 50% or ≥ 26.5 μmol/L from baseline) and hyperkalemia (potassium ≥ 5.5 mmol/L) within 14 and 30 days., Results: Of the 1730 kidney transplant recipients, 189 (11%) had at least one NSAID prescription over a median follow-up of 5 years (IQR 2-9) (280 unique prescriptions). The majority were prescribed by family physicians (67%). Approximately 25% and 50% of prescriptions had serum creatinine and potassium testing within 14 and 30 days, respectively. Of those with lab measurements within 14 days, 13% of prescriptions were associated with AKI and 5% had hyperkalemia., Conclusions: Contrary to guidelines, one in 10 kidney transplant recipients are prescribed an NSAID, and most do not get follow-up testing of graft function and hyperkalemia. These findings call for improved education of patients and primary care providers., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Importance: Severe acute kidney injury (AKI) is a serious postoperative complication. A tool for predicting the risk of AKI requiring kidney replacement therapy (KRT) after major noncardiac surgery might assist with patient counseling and targeted use of measures to reduce this risk., Objective: To derive and validate a predictive model for AKI requiring KRT after major noncardiac surgery., Design, Setting, and Participants: In this prognostic study, 5 risk prediction models were derived and internally validated in a population-based cohort of adults without preexisting kidney failure who underwent noncardiac surgery in Alberta, Canada, between January 1, 2004, and December 31, 2013. The best performing model and corresponding risk index were externally validated in a population-based cohort of adults without preexisting kidney failure who underwent noncardiac surgery in Ontario, Canada, between January 1, 2007, and December 31, 2017. Data analysis was conducted from September 1, 2019, to May 31, 2021., Exposures: Demographic characteristics, surgery type, laboratory measures, and comorbidities before surgery., Main Outcomes and Measures: Acute kidney injury requiring KRT within 14 days after surgery. Discrimination was assessed using the C statistic; calibration was assessed using calibration intercept and slope. Logistic recalibration was used to optimize model calibration in the external validation cohort., Results: The derivation cohort included 92 114 patients (52.2% female; mean [SD] age, 62.3 [18.0] years), and the external validation cohort included 709 086 patients (50.8% female; mean [SD] age, 61.0 [16.0] years). A total of 529 patients (0.6%) developed postoperative AKI requiring KRT in the derivation cohort, and 2956 (0.4%) developed postoperative AKI requiring KRT in the external validation cohort. The following factors were consistently associated with the risk of AKI requiring KRT: younger age (40-69 years: odds ratio [OR], 2.07 [95% CI, 1.69-2.53]; <40 years: OR, 3.73 [95% CI, 2.61-5.33]), male sex (OR, 1.55; 95% CI, 1.28-1.87), surgery type (colorectal: OR, 4.86 [95% CI, 3.28-7.18]; liver or pancreatic: OR, 6.46 [95% CI, 3.85-10.83]; other abdominal: OR, 2.19 [95% CI, 1.66-2.89]; abdominal aortic aneurysm repair: OR, 19.34 [95% CI, 14.31-26.14]; other vascular: OR, 7.30 [95% CI, 5.48-9.73]; thoracic: OR, 3.41 [95% CI, 2.07-5.59]), lower estimated glomerular filtration rate (OR, 0.97; 95% CI, 0.97-0.97 per 1 mL/min/1.73 m2 increase), lower hemoglobin concentration (OR, 0.99; 95% CI, 0.98-0.99 per 0.1 g/dL increase), albuminuria (mild: OR, 1.88 [95% CI, 1.52-2.33]; heavy: OR, 3.74 [95% CI, 2.98-4.69]), history of myocardial infarction (OR, 1.63; 95% CI, 1.32-2.03), and liver disease (mild: OR, 2.32 [95% CI, 1.66-3.24]; moderate or severe: OR, 4.96 [95% CI, 3.58-6.85]). In external validation, a final model including these variables showed excellent discrimination (C statistic, 0.95; 95% CI, 0.95-0.96), with sensitivity of 21.2%, specificity of 99.9%, positive predictive value of 38.1%, and negative predictive value of 99.7% at a predicted risk threshold of 10% or greater., Conclusions and Relevance: The findings suggest that this risk model can predict AKI requiring KRT after noncardiac surgery using routine preoperative data. The model may be feasible for implementation in clinical perioperative risk stratification for severe AKI.

Background: Guidelines recommend referral for nephrology consultation for people with severe chronic kidney disease (CKD) to improve care and renal outcomes, yet the advocated benefits of nephrology referral on CKD progression in this patient population are unclear., Methods: We linked laboratory and administrative data in Alberta, Canada to identify adults with stage 4 CKD between 2002 and 2014 (follow-up end on March 31, 2017). We studied the association between time-varying receipt of outpatient nephrology consultation and kidney failure (the earlier of renal replacement initiation or eGFR < 10 mL/min/1.73 m 2 for more than 3 months), accounting for the competing risk of death., Results: Of the 14,382 participants, 41% were ≥ 85 years old, 33% saw a nephrologist as an outpatient, 9% developed kidney failure, and 53% died over a median of 2.6 years. Compared with people who did not see a nephrologist before or at 7 months (median time to consultation), those who did were more likely to develop kidney failure [5-year risk (95% CI) 0.23 (0.21-0.24) vs 0.07 (0.065-0.075)]. With increasing age or higher eGFR, the 5-year risk of kidney failure became progressively smaller, from 0.24 (0.18-0.29) at age < 65 to 0.01 (0.006-0.015) at age ≥ 85 years and from 0.21 (0.18-0.23) at eGFR 15-19 to 0.066 (0.060-0.072) at eGFR 25-29 mL/min/1.73 m 2 ; yet, the hazard ratio of kidney failure (1.6-4.3) increased following nephrology consultation in people who were older or had higher eGFR., Conclusions: Adults with stage 4 CKD who see a nephrologist are more likely to develop kidney failure than those who don't, especially within lower absolute risk categories. Although selective referral may explain these findings, there is no evidence of an association between nephrology care and reduced risk of kidney failure in people with severe CKD. Studies are needed to assess the benefits of nephrology consultation in people with moderate CKD., (© 2020. Italian Society of Nephrology.)

Importance: The burden of chronic kidney disease (CKD) is expected to increase worldwide as the global population ages, potentially increasing the demand for nephrology services. Understanding whether CKD inevitably progresses or may regress can inform clinical decision-making and health policy., Objective: To study CKD progression and regression by age in adults with CKD., Design, Setting, and Participants: This population-based cohort study used linked administrative and laboratory data to assess adults in the province of Alberta, Canada, with incident mild, moderate, or severe CKD, defined by estimated glomerular filtration rate (eGFR) of 45 to 59, 30 to 44, or 15 to 29 mL/min/1.73 m2 for longer than 3 months, from April 1, 2009, to March 31, 2015. Data were analyzed from July 20 to November 30, 2020., Exposures: Age., Main Outcomes and Measures: Time to the earliest of CKD regression or progression (defined as sustained increase or drop in eGFR category for >3 months, respectively, and a ≥25% increase or decrease in eGFR from baseline, respectively), kidney failure (the earlier of kidney replacement initiation or eGFR <15 mL/min/1.73 m2 for >3 months), death, or censoring (outmigration, 5 years of follow-up, or end of study on March 31, 2017)., Results: Study participants with CKD (55.2% women and 44.8% men) included 81 320 with mild CKD (mean [SD] age, 72.4 [11.3] years), 35 929 with moderate CKD (mean [SD] age, 77.1 [11.5] years), and 12 237 with severe CKD (mean [SD] age, 76.6 [13.8] years). The annual incidence of CKD increased with advancing age, from 180 per 100 000 population younger than 65 years to 7250 per 100 000 in those 85 years or older. After cohort entry, the 5-year probability of regression was similar to that of progression or kidney failure in mild (14.3% vs 14.6%), moderate (18.9% vs 16.5%), and severe (19.3% vs 20.4%) CKD. As mortality at 5 years increased with advancing age in moderate (from 9.6% for age <65 years to 48.4% for age ≥85 years) and severe (from 10.8% for age <65 years to 60.2% for age ≥85 years) CKD, the risk of progression or kidney failure decreased substantially (for moderate CKD, from 32.3% for <65 years to 9.4% for ≥85 years; for severe CKD, from 55.2% for <65 years to 4.7% for ≥85 years), whereas the probabilities of regression varied to a lesser extent (for moderate CKD, from 22.5% for <65 years to 15.4% for ≥85 years; for severe CKD, from 13.9% for <65 years to 18.7% for ≥85 years)., Conclusions and Relevance: This cohort study found that with advancing age, CKD regression and death were more likely than CKD progression or kidney failure. These findings have important implications for patient care and for assessing the potential effect of population aging on the burden of CKD.

Better understanding of kidney function after living donor nephrectomy and how it differs by donor characteristics can inform patient selection, counselling, and follow-up care. To evaluate this, we conducted a retrospective matched cohort study of living kidney donors in Alberta, Canada between 2002-2016, using linked healthcare administrative databases. We matched 604 donors to 2,414 healthy non-donors from the general population based on age, sex, year of cohort entry, urban residence and the estimated glomerular filtration rate (eGFR) before cohort entry (nephrectomy date for donors and randomly assigned date for non-donors). The primary outcome was the rate of eGFR change over time (median follow-up seven years; maximum 15 years). The median age of the cohort was 43 years, 64% women, and the baseline (pre-donation) eGFR was 100 mL/min/1.73 m 2 . Overall, from six weeks onwards, the eGFR increased by +0.35 mL/min/1.73 m 2 per year (95% confidence interval +0.21 to +0.48) in donors and significantly decreased by -0.85 mL/min/1.73 m 2 per year (-0.94 to -0.75) in the matched healthy non-donors. The change in eGFR between six weeks to two years, two to five years, and over five years among donors was +1.06, +0.64, and -0.06 mL/min/1.73 m 2 per year, respectively. In contrast to the steady age-related decline in kidney function in non-donors, post-donation kidney function on average initially increased by 1 mL/min/1.73 m 2 per year attributable to glomerular hyperfiltration, which began to plateau by five years post-donation. Thus, the average change in eGFR over time is significantly different between donors and non-donors., (Copyright © 2020 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Importance: Comparative outcome data examining the association of dialysis initiation with hospital length of stay and intensity of care in older adults with kidney failure are scarce, and prior studies are limited to patients treated by nephrology teams., Objective: To compare in-hospital days and intensity of care among older adults with kidney failure who were treated vs not treated with maintenance dialysis., Design, Setting, and Participants: This population-based, retrospective cohort study included adults in Alberta, Canada, 65 years or older with kidney failure, defined by at least 2 consecutive outpatient estimated glomerular filtration rate values of less than 10 mL/min/1.73 m2 spanning a period of at least 90 days from May 15, 2002, to March 31, 2014. Data were analyzed from August 1, 2017, to August 29, 2019., Exposures: Time-varying exposure to maintenance dialysis for treatment of kidney failure., Main Outcomes and Measures: The primary outcome was rate of in-hospital days. Secondary outcomes included rates of hospital admissions, intensive care unit admissions, cardiopulmonary resuscitations, inpatient palliative care, and emergency department visits; risk of in-hospital death; and time to admission to long-term care., Results: A total of 968 patients (median age, 78.5 [interquartile range, 72.4-84.7] years; 489 men [50.5%]; median follow-up, 2.0 [interquartile range, 0.8-3.9] years) were included in the analysis. Patients who underwent dialysis spent more adjusted in-hospital days per person-year (36.25 [95% CI, 30.72-41.77] vs 14.65 [95% CI, 12.28-17.02]; incidence rate ratio [IRR], 2.47 [95% CI, 1.99-3.08]). However, the dialysis group did not have a higher rate of hospital admissions (1.18 [95% CI 1.07-1.29] vs 1.32 [95% CI 1.17-1.48] per year; IRR, 0.89 [95% CI, 0.77-1.03]). Patients in the dialysis group had a higher rate of intensive care unit admissions per 1000 hospitalizations (98.37 [95% CI, 81.09-115.65] vs 54.51 [95% CI, 37.76-71.26]; IRR, 1.80 [95% CI, 1.28-2.54]) and lower rates of inpatient palliative care per 1000 in-hospital days (3.92 [95% CI, 3.13-4.72] vs 8.60 [95% CI, 6.3-11.0]; IRR, 0.45 [95% CI, 0.32-0.64])., Conclusions and Relevance: In this cohort study, compared with nondialysis care, patients who received maintenance dialysis spent more time in the hospital and were more likely to be admitted to intensive care units. This finding suggests trade-offs between longer survival and higher intensity of use of health care services as a function of dialysis initiation. Maintenance dialysis may be a proxy for the type of philosophy of care driving increased in-hospital time and intensive care and less use of palliative care.

Background: The Kidney Failure Risk Equation (KFRE) predicts risk of progression to kidney failure and is used to guide clinical decisions for patients with chronic kidney disease (CKD)., Methods: The KFRE was implemented to guide access to multidisciplinary care for CKD patients in Alberta, Canada, based on their 2-year risk of kidney failure. We used a mixed methods approach to investigate patients' and providers' perspectives and experiences 1 year following KFRE implementation. We conducted post-implementation interviews with multidisciplinary clinic providers and with low-risk patients who transitioned from multidisciplinary to general nephrology care. We also administered pre- and post-implementation patient care experience surveys, targeting both low-risk patients discharged to general nephrology and high-risk patients who remained in the multidisciplinary clinic, and provider job satisfaction surveys., Results: Twenty-seven interviews were conducted (9 patients, 1 family member, 17 providers). Five categories were identified among patients and providers: targeted care; access to resources outside the multidisciplinary clinics; self-efficacy; patient reassurance and reduced stress; and transition process for low-risk patients Two additional categories were identified among providers only: anticipated concerns and job satisfaction. Patients and providers reported that the risk-based approach allowed the clinic to target care to those most likely to experience kidney failure and most likely to benefit from multidisciplinary care. While some participants indicated the risk-based model enhanced the sustainability of the clinics, others expressed concern that care for low-risk patients discharged from multidisciplinary care, or those now considered ineligible, may be inadequate. Overall, 413 patients completed the care experience survey and 73 providers completed the workplace satisfaction survey. The majority of patients were satisfied with their care in both periods with no overall differences. When considering the responses "Always" and "Often" together versus not, there were statistically significant improvements in domains of access to care, caring staff, and safety of care. There were no differences in healthcare providers' job satisfaction following KFRE implementation., Conclusions: Patients and healthcare providers reported that the risk-based approach improved the focus of the multidisciplinary CKD clinics by targeting patients at highest risk, with survey results suggesting no difference in patient care experience or healthcare provider job satisfaction.

Background: Guidelines recommend nephrology referral for people with advanced non-dialysis-dependent chronic kidney disease, based mostly on survival benefits seen in retrospective studies of dialysis patients, which may not be generalizable to the broader population with chronic kidney disease. We aimed to examine the association between outpatient nephrology consultation and survival in adults with stage 4 chronic kidney disease., Methods: We linked population-based laboratory and administrative data from 2002 to 2014 in Alberta, Canada, on adults with stage 4 chronic kidney disease (sustained estimated glomerular filtration rate ≥ 15 to < 30 mL/min/1.73 m 2 for > 90 d), who had never had kidney failure and had had no outpatient nephrology encounter in the 2 years preceding study entry. Participants who had never had an outpatient nephrology visit before renal replacement treatment were considered "unexposed." Participants who saw a nephrologist during follow-up were considered "unexposed" before the first outpatient nephrology visit and "exposed" thereafter. The primary outcome was all-cause mortality., Results: Of the 14 382 study participants (median follow-up 2.7 yr), 64% were aged ≥ 80 years, 35% saw a nephrologist and 66% died during follow-up. Nephrology consultation was associated with lower mortality (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.82-0.93). The association was strongest in people < 70 years (HR 0.78, 95% CI, 0.65-0.92), progressively weaker with increasing age, and absent in people ≥ 90 years (HR 1.05, 95% CI 0.88-1.25)., Interpretation: The survival benefit of nephrology consultation in adults with stage 4 chronic kidney disease may be smaller than expected and appears to attenuate with increasing age. These findings should inform recommendations for nephrology referral considering the advanced age of the patient population meeting current referral criteria., Competing Interests: Competing interests: Robert Quinn has a patent issued, for a Dialysis Measurement Analysis and Reporting system — a Web-based data collection system to measure performance in dialysis programs. Mohammed Karim reports grants from the BC SUPPORT Unit, Michael Smith Foundation for Health Research and Natural Sciences and Engineering Research Council of Canada, and personal fees from Biogen Inc., outside the submitted work. No other competing interests were declared., (© 2019 Joule Inc. or its licensors.)

Comparisons of survival between dialysis and nondialysis care for older adults with kidney failure have been limited to those managed by nephrologists, and are vulnerable to lead and immortal time biases. So we compared time to all-cause mortality among older adults with kidney failure treated vs. not treated with chronic dialysis. Our retrospective cohort study used linked administrative and laboratory data to identify adults aged 65 or more years of age in Alberta, Canada, with kidney failure (2002-2012), defined by two or more consecutive outpatient estimated glomerular filtration rates less than 10 mL/min/1.73m 2 , spanning 90 or more days. We used marginal structural Cox models to assess the association between receipt of dialysis and all-cause mortality by allowing control for both time-varying and baseline confounders. Overall, 838 patients met inclusion criteria (mean age 79.1; 48.6% male; mean estimated glomerular filtration rate 7.8 mL/min/1.73m 2 ). Dialysis treatment (vs. no dialysis) was associated with a significantly lower risk of death for the first three years of follow-up (hazard ratio 0.59 [95% confidence interval 0.46-0.77]), but not thereafter (1.22 [0.69-2.17]). However, dialysis was associated with a significantly higher risk of hospitalization (1.40 [1.16-1.69]). Thus, among older adults with kidney failure, treatment with dialysis was associated with longer survival up to three years after reaching kidney failure, though with a higher risk of hospital admissions. These findings may assist shared decision-making about treatment of kidney failure., (Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.)

Objective: To determine rates of major bleeding by level of kidney function for older adults with atrial fibrillation starting warfarin., Design: Retrospective cohort study., Setting: Community based, using province wide laboratory and administrative data in Alberta, Canada., Participants: 12,403 adults aged 66 years or more, with atrial fibrillation who started warfarin treatment between 1 May 2003 and 31 March 2010 and had a measure of kidney function at baseline. Kidney function was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation and participants were categorised based on estimated glomerular filtration rate (eGFR): ≥ 90, 60-89, 45-59, 30-44, 15-29, <15 mL/min/1.73 m(2). We excluded participants with end stage renal disease (dialysis or renal transplant) at baseline., Main Outcome Measures: Admission to hospital or visit to an emergency department for major bleeding (intracranial, upper and lower gastrointestinal, or other)., Results: Of 12,403 participants, 45% had an eGFR <60 mL/min/1.73 m(2). Overall, 1443 (11.6%) experienced a major bleeding episode over a median follow-up of 2.1 (interquartile range: 1.0-3.8) years. During the first 30 days of warfarin treatment, unadjusted and adjusted rates of major bleeding were higher at lower eGFR (P for trend <0.001 and 0.001, respectively). Adjusted bleeding rates per 100 person years were 63.4 (95% confidence interval 24.9 to 161.6) in participants with eGFR <15 mL/min/1.73 m(2) compared with 6.1 (1.9 to 19.4) among those with eGFR >90 mL/min/1.73 m(2) (adjusted incidence rate ratio 10.3, 95% confidence interval 2.3 to 45.5). Similar associations were observed at more than 30 days after starting warfarin, although the magnitude of the increase in rates across eGFR categories was attenuated. Across all eGFR categories, adjusted rates of major bleeding were consistently higher during the first 30 days of warfarin treatment compared with the remainder of follow-up. Increases in major bleeding rates were largely due to gastrointestinal bleeding (3.5-fold greater in eGFR <15 mL/min/1.73 m(2) compared with ≥ 90 mL/min/1.73 m(2)). Intracranial bleeding was not increased with worsening kidney function., Conclusions: Reduced kidney function was associated with an increased risk of major bleeding among older adults with atrial fibrillation starting warfarin; excess risks from reduced eGFR were most pronounced during the first 30 days of treatment. Our results support the need for careful consideration of the bleeding risk relative to kidney function when assessing the risk-benefit ratio of warfarin treatment in people with chronic kidney disease and atrial fibrillation, particularly in the first 30 days of treatment., (© Jun et al 2015.)

Background: Fluid removal during dialysis, also known as ultrafiltration (UF), leads to intradialytic hypotension (IDH) in a significant number of patients treated with hemodialysis (HD) and is associated with an increase in morbidity and mortality. At present, there are no accepted standards of practice for the prevention or treatment of IDH. Relative blood volume monitoring (BVM) is based on the concept that the hematocrit increases with UF, relative to the patient's baseline hematocrit. The use of BVM biofeedback, whereby the HD machine automatically adjusts the rate of UF based on the relative blood volume, has been proposed for the prevention of IDH., Methods/design: This is a 22-week randomized crossover trial. Participants undergo a 4-week run-in phase to standardize medications and dialysis prescriptions. Subsequently, participants are randomized to standard HD or to BVM biofeedback for a period of 8 weeks followed by a 2-week washout phase before crossing over. The dialysis prescription remains identical for both arms. The primary outcome is the frequency of symptomatic IDH as defined by an abrupt drop in the systolic blood pressure of ≥ 20 mm Hg accompanied by headache, dizziness, loss of consciousness, thirst, dyspnea, angina, muscle cramps or vomiting. Secondary outcomes include the number of symptomatic IDH episodes and any reduction in IDH episodes, nursing interventions, dialysis adequacy, total body water, extra- and intracellular fluid volumes, brain natriuretic peptide and cardiac troponin levels, blood pressure, antihypertensive medication use, patient symptoms and quality of life., Discussion: Our study will determine the impact of using BVM biofeedback to prevent IDH and other serious adverse events in susceptible patients., Trial Registration: Clinicaltrials.gov NCT01988181 (6 November 2013).

Context: Studies of kidney failure in older adults have focused on receipt of dialysis, which may underestimate the burden of disease if older people are less likely to receive treatment., Objective: To determine the extent to which age is associated with the likelihood of treatment of kidney failure., Design, Setting, and Participants: Community-based cohort study of 1,816,824 adults in Alberta, Canada, who had outpatient estimated glomerular filtration rate (eGFR) measured between May 1, 2002, and March 31, 2008, with a baseline eGFR of 15 mL/min/1.73 m2 or higher and who did not require renal replacement therapy at baseline. Age was categorized as 18 to 44, 45 to 54, 55 to 64, 65 to 74, 75 to 84, and 85 or more years and eGFR as 90 or higher, 60 to 89, 45 to 59, 30 to 44, and 15 to 29 mL/min/1.73 m2., Main Outcome Measures: Adjusted rates of treated kidney failure (receipt of dialysis or kidney transplantation), untreated kidney failure (progression to eGFR <15 mL/min/1.73 m2 without renal replacement therapy), and death., Results: During a median follow-up of 4.4 years, 97,451 (5.36%) died, 3295 (0.18%) developed kidney failure that was treated and 3116 (0.17%) developed kidney failure that went untreated. Within each eGFR stratum the rate of treated kidney failure was higher in younger compared with older people. For example, in the lowest eGFR stratum (15-29 mL/min/1.73 m2), adjusted rates of treated kidney failure were more than 10-fold higher among the youngest (18-44 years) compared with the oldest (≥85 years) groups (adjusted rate, 24.00 [95% CI, 14.78-38.97] vs 1.53 [95% CI, 0.59-3.99] per 1000 person-years, respectively; P < .001). Rates of untreated kidney failure were consistently higher at older ages. In the eGFR stratum of 15 to 29 mL/min/1.73 m2, adjusted rates of untreated kidney failure were more than 5-fold higher among the oldest (≥85 years), compared with the youngest (18-44 years) groups (adjusted rate, 19.95 [95% CI, 15.79-25.19] vs 3.53 [95% CI, 1.56-8.01] per 1000 person-years, respectively; P < .001). Rates of kidney failure overall (treated and untreated combined) demonstrated less variation across age groups; eg, the adjusted rate per 1000 person years for those with eGFR of 15-29 mL/min/1.73 m2 was 36.45 (95% CI, 24.46-54.32) among participants aged 18 to 44 years and 20.19 (95% CI, 15.27-26.69) among those aged 85 years or older (P = .01)., Conclusion: In Alberta, Canada, rates of untreated kidney failure are significantly higher in older compared with younger individuals.

Background: Administrative data are commonly used for surveillance of chronic medical conditions. The purpose of this study was to determine the validity of an algorithm derived from administrative data for identifying chronic kidney disease (CKD) compared to the reference standard of estimated glomerular filtration rate (eGFR)., Methods: We identified adults from the province of Alberta with at least two outpatient serum creatinine measurements within a 1-year time period. Validity indices were estimated for CKD using up to 3 years of administrative data (physician billing claims and hospital discharge abstracts) for various case-definition combinations. For each algorithm, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated against two reference standard definitions of CKD (two eGFR measurements <60 mL/min/1.73m(2) or mean eGFR < 30 mL/min/1.73m(2))., Results: A total of 321 293 eligible subjects were identified. Irrespective of the algorithm, sensitivities for defining CKD (eGFR < 60 mL/min/1.73m(2)) using administrative codes were low. A case-definition algorithm employing two physician claims or one hospitalization within a 2-year period had sensitivity of 19.4%, specificity of 97.2%, PPV of 60.1% and NPV of 84.8% for detecting CKD. Estimates of sensitivity were higher when <30 mL/min/1.73m(2) was used as the reference standard, although PPVs were lower and consistently less than 50%., Conclusion: These results, using eGFR as a reference standard, suggest that administrative data have insufficient sensitivity and PPV for CKD surveillance, although they may be useful when highly specific algorithms are required for research purposes.

Context: The current staging system for chronic kidney disease is based primarily on estimated glomerular filtration rate (eGFR) with lower eGFR associated with higher risk of adverse outcomes. Although proteinuria is also associated with adverse outcomes, it is not used to refine risk estimates of adverse events in this current system., Objective: To determine the association between reduced GFR, proteinuria, and adverse clinical outcomes., Design, Setting, and Participants: Community-based cohort study with participants identified from a province-wide laboratory registry that includes eGFR and proteinuria measurements from Alberta, Canada, between 2002 and 2007. There were 920 985 adults who had at least 1 outpatient serum creatinine measurement and who did not require renal replacement treatment at baseline. Proteinuria was assessed by urine dipstick or albumin-creatinine ratio (ACR)., Main Outcome Measures: All-cause mortality, myocardial infarction, and progression to kidney failure., Results: The majority of individuals (89.1%) had an eGFR of 60 mL/min/1.73 m(2) or greater. Over median follow-up of 35 months (range, 0-59 months), 27 959 participants (3.0%) died. The fully adjusted rate of all-cause mortality was higher in study participants with lower eGFRs or heavier proteinuria. Adjusted mortality rates were more than 2-fold higher among individuals with heavy proteinuria measured by urine dipstick and eGFR of 60 mL/min/1.73 m(2) or greater, as compared with those with eGFR of 45 to 59.9 mL/min/1.73 m(2) and normal protein excretion (rate, 7.2 [95% CI, 6.6-7.8] vs 2.9 [95% CI, 2.7-3.0] per 1000 person-years, respectively; rate ratio, 2.5 [95% CI, 2.3-2.7]). Similar results were observed when proteinuria was measured by ACR (15.9 [95% CI, 14.0-18.1] and 7.0 [95% CI, 6.4-7.6] per 1000 person-years for heavy and absent proteinuria, respectively; rate ratio, 2.3 [95% CI, 2.0-2.6]) and for the outcomes of hospitalization with acute myocardial infarction, end-stage renal disease, and doubling of serum creatinine level., Conclusion: The risks of mortality, myocardial infarction, and progression to kidney failure associated with a given level of eGFR are independently increased in patients with higher levels of proteinuria.