Variation in the level of eGFR at dialysis initiation across dialysis facilities and geographic regions

Prediction models for earlier stages of chronic kidney disease

PURPOSE OF REVIEW

Identifying patients with risk of developing progressive chronic kidney disease (CKD) early is an important step in improving kidney care. This review discusses four recently developed models, two which predict risk of new onset disease, and two which predict progression earlier in the course of disease.

RECENT FINDINGS

Several models predicting CKD incidence and progression have been recently developed and externally validated. A connecting theme across these models is the use of data beyond estimated glomerular filtration rate, allowing for greater accuracy and personalization. Two models were developed with stratification by diabetes status, displaying excellent model fit with and without variables like use of diabetes medication and hemoglobin A1C. Another model was designed to be patient facing, not requiring the knowledge of any laboratory values for use. The final model was developed using lab data and machine learning. These models demonstrated high levels of discrimination and calibration in external validation, suggesting suitability for clinical use.

SUMMARY

Models that predict risk of CKD onset and progression have the potential to significantly reduce disease burden, financial cost, and environmental output from CKD through upstream disease prevention and slowed progression. These models should be implemented and evaluated prospectively in primary care settings.

Geographic Dialysis Facility Density and Early Dialysis Initiation

Importance

The decision of when to start maintenance hemodialysis may be affected by health system-level support for high-intensity care as manifested by area dialysis facility density. Yet an association between early hemodialysis initiation and higher area density of dialysis facilities has not been shown.

Objective

To examine whether there is an association between area dialysis facility density and earlier dialysis initiation.

Design, Setting, and Participants

Cross-sectional analysis was conducted of publicly reported claims and geographic-based population data collected in the Medical Evidence files of the US Renal Data System (USRDS), a comprehensive registry of all patients initiating hemodialysis in the US, from calendar years 2011 through 2019. Data were linked to the American Community Survey, using residential zip codes, and then to health service area (HSA) primary care and hospitalization benchmarks, using the Dartmouth Atlas crosswalk. Data were analyzed from November 1, 2021, to August 31, 2023.

Exposure

Dialysis facility density at the level of HSA (number of dialysis facilities per 100 000 HSA residents) split into 5 categories.

Main Outcomes and Measures

The odds of hemodialysis initiation at an estimated glomerular filtration rate (eGFR) greater than 10 mL/min/1.73 m2 vs less than or equal to 10 mL/min/1.73 m2.

Results

Hemodialysis was initiated in a total of 844 466 individuals at 3397 HSAs at a mean (SD) eGFR of 8.9 (3.8) mL/min/1.73 m2. Their mean (SD) age was 63.5 (14.7) years, and 484 346 participants (57.4%) were men. In the HSA category with the highest facility density, individuals were younger (63.3 vs 65.2 years in least-dense HSAs), poorer (mean percent of households living in poverty, 10.4% vs 8.4%), and more commonly had a higher percentage of Black individuals (40.6% vs 11.3%). More individuals in the dialysis-dense HSAs than least-dense HSAs had diabetes (60.1% vs 58.5%) and fewer had access to predialysis nephrology care (60.8% vs 64.1%); the rates of heart failure and immobility varied, but not in a consistent pattern, by HSA dialysis density. The mean (SD) facility density was 4.1 (1.89) centers per 100 000 population in the most dialysis-dense HSAs. Compared with patients in HSAs with a mean of 1.0 per 100 000 population, the odds of hemodialysis initiation at eGFR greater than 10 mL/min/1.73 m2 were 1.07 (95% CI, 1.03-1.11) for patients in the densest HSAs, and compared with HSAs with 0 facilities, the odds of early hemodialysis initiation were 1.06 (95% CI, 1.02-1.10) for patients in the densest HSAs.

Conclusions and Relevance

In this cross-sectional study of USRDS- and HSA-level data, HSA dialysis density was associated with early hemodialysis initiation.

Physician Variation and the Impact of Payment Model in Cardiac Imaging

BACKGROUND

The influence of fee-for-service reimbursement on cardiac imaging has not been compared with other payment models. Furthermore, variation in ordering practices is not well understood.

METHODS AND RESULTS

This retrospective, population-based cohort study using linked administrative data from Alberta, Canada included adults with chronic heart disease (atrial fibrillation, coronary artery disease, and heart failure) seen by cardiac specialists for a new outpatient consultation April 2012 to December 2018. Generalized linear mixed-effects models estimated the association of payment model (including the ability to bill to interpret imaging tests) and the use of cardiac imaging and quantified variation in cardiac imaging. Among 31 685 adults seen by 308 physicians at 136 sites, patients received an observed mean of 0.67 (95% CI, 0.67-0.68) imaging tests per consultation. After adjustment, patients seeing fee-for-service physicians had 2.07 (95% CI, 1.68-2.54) and fee-for-service physicians with ability to interpret had 2.87 (95% CI, 2.16-3.81) times the rate of receiving a test than those seeing salaried physicians. Measured patient, physician, and site effects accounted for 31% of imaging variation and, following adjustment, reduced unexplained site-level variation 40% and physician-level variation 29%.

CONCLUSIONS

We identified substantial variation in the use of outpatient cardiac imaging related to physician and site factors. Physician payment models have a significant association with imaging use. Our results raise concern that payment models may influence cardiac imaging practice. Similar methods could be applied to identify the source and magnitude of variation in other health care processes and outcomes.

Effects of a Knowledge-Translation Intervention on Early Dialysis Initiation: A Cluster Randomized Trial

BACKGROUND

The Initiating Dialysis Early and Late (IDEAL) trial, published in 2009, found no clinically measurable benefit with respect to risk of mortality or early complications with early dialysis initiation versus deferred dialysis start. After these findings, guidelines recommended an intent-to-defer approach to dialysis initiation, with the goal of deferring it until clinical symptoms arise.

METHODS

To evaluate a four-component knowledge translation intervention aimed at promoting an intent-to-defer strategy for dialysis initiation, we conducted a cluster randomized trial in Canada between October 2014 and November 2015. We randomized 55 clinics, 27 to the intervention group and 28 to the control group. The educational intervention, using knowledge-translation tools, included telephone surveys from a knowledge-translation broker, a 1-year center-specific audit with feedback, delivery of a guidelines package, and an academic detailing visit. Participants included adults who had at least 3 months of predialysis care and who started dialysis in the first year after the intervention. The primary efficacy outcome was the proportion of patients who initiated dialysis early (at eGFR >10.5 ml/min per 1.73 m²). The secondary outcome was the proportion of patients who initiated in the acute inpatient setting.

RESULTS

The analysis included 3424 patients initiating dialysis in the 1-year follow-up period. Of these, 509 of 1592 (32.0%) in the intervention arm and 605 of 1832 (33.0%) in the control arm started dialysis early. There was no difference in the proportion of individuals initiating dialysis early or in the proportion of individuals initiating dialysis as an acute inpatient.

CONCLUSIONS

A multifaceted knowledge translation intervention failed to reduce the proportion of early dialysis starts in patients with CKD followed in multidisciplinary clinics.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

ClinicalTrials.gov, NCT02183987. Available at: https://clinicaltrials.gov/ct2/show/NCT02183987.

Protocol for a prospective, cluster randomized trial to evaluate routine and deferred dialysis initiation (RADDI) in Chinese population

BACKGROUND

The timing of when to initiate dialysis for progressive chronic kidney disease (CKD) patients has not been well established. There has been a strong trend for early dialysis initiation for these patients over the past decades. However, the perceived survival advantage of early dialysis has been questioned by a series of recent observational studies. The only randomized controlled trial (RCT) research on this issue found the all-cause mortality, comorbidities, and quality of life showed no difference between early and late dialysis starters. To better understand optimal timing for dialysis initiation, our research will evaluate the efficacy and safety of deferred dialysis initiation in a large Chinese population.

METHODS

The trial adopts a multicenter, cluster randomized, single-blind (outcomes assessor), and endpoint-driven design. Eligible participants are 18-80 years old, in stable CKD stages 4-5 (eGFR > 7 ml/min /1.73 m2), and with good heart function (NYHA grade I or II). Participants will be randomized into a routine or deferred dialysis group. The reference eGFR at initiating dialysis for asymptomatic patients is 7 ml/min /1.73 m2 (routine dialysis group) and 5 ml/min/1.73 m2 or less (deferred dialysis group) in each group. The primary endpoint will be the difference of all-cause mortality and acute nonfatal cerebro-cardiovascular events between the two groups. The secondary outcomes include hospitalization rate and other safety indices. The primary and secondary outcomes will be analyzed by appropriate statistical methods.

DISCUSSION

This study protocol represents a large, cluster randomized study evaluating deferred and routine dialysis intervention for an advanced CKD population. The reference eGFR to initiate dialysis for both treatment groups is targeted at less than 7 ml/min/1.73m2. With this design, we aim to eliminate lead-time and survivor bias and avoid selection bias and confounding factors. We acknowledge that the study has limitations. Even so, given the low-targeted eGFR values of both arms, this study still has potential economic, health, and scientific implications. This research is unique in that such a low targeted eGFR value has never been studied in a clinical trial.

TRIAL REGISTRATION

The trial has been approved by ClinicalTrials.gov (Trial registration ID NCT02423655). The date of registration was April 22, 2015.

Facility Variation and Predictors of Do Not Resuscitate Orders of Hemodialysis Patients in Canada: DOPPS

BACKGROUND

Life expectancy in patients with end-stage kidney disease treated with hemodialysis (HD) is limited, and as such, the presence of an advanced care directive (ACD) may improve the quality of death as experienced for patients and families. Strategies to discuss and implement ACDs are limited with little being known about the status of Do Not Resuscitate (DNR) orders in the Canadian HD population.

OBJECTIVES

Using data from the Dialysis Outcomes and Practice Patterns Study (DOPPS), we set out to (1) examine the variability in DNR orders across Canada and its largest province, Ontario and (2) identify clinical and functional status measures associated with a DNR order.

DESIGN

We conducted a retrospective cohort study using data from the DOPPS Canada Phase 4 to 6 from 2009 to 2017.

SETTING

DOPPS facilities in Canada.

PATIENTS

All adults (>18 years) who initiated chronic HD with a documented ACD were included.

MEASUREMENTS

ACD and DNR orders.

METHODS

Descriptive statistics were compared for baseline characteristics (demographics, comorbidities, medications, facility characteristics, and patient functional status) and DNR status. The crude proportion of patients per facility with a DNR order was calculated across Canada and Ontario. Functional status was determined by activities of daily living and components of the Kidney Disease Quality of Life (KDQOL)-validated questionnaire. We used generalized estimating equations (GEEs) to create sequential multivariable models (demographics, comorbidities, and functional status) of variables associated with DNR status.

RESULTS

A total of 1556 (96% of total) patients treated with HD had a documented ACD and were included. A total of 10% of patients had a DNR order. The crude variation of DNR status differed considerably across facilities within Canada, between Ontario and non-Ontario, and within Ontario (interprovince variation = 6.3%-17.1%, Ontario vs non-Ontario = 8.2% vs 11.7%, intraprovincial variation [Ontario] = 1%-26%). Patients with a DNR order were more commonly older, white, with cardiac comorbidities, with less or shorter predialysis care compared with those without a DNR order. Patients with a DNR order reported lower energy, more difficulty with transfers, meal preparation, household tasks, and financial management. In a multivariate model, age, cardiac disease, stroke, dialysis duration, and intradialytic weight gain were associated with DNR status.

LIMITATIONS

Relatively small number of events or measures in certain categories.

CONCLUSIONS

A large inter- and intraprovincial (Ontario) variation was observed regarding DNR orders across Canada highlighting areas for potential quality improvement. While functional status did not appear to have a bearing on the presence of a DNR order, the presence of various comorbidities was associated with the presence of a DNR order.

Dialysis initiation, modality choice, access, and prescription: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Globally, the number of patients undergoing maintenance dialysis is increasing, yet throughout the world there is significant variability in the practice of initiating dialysis. Factors such as availability of resources, reasons for starting dialysis, timing of dialysis initiation, patient education and preparedness, dialysis modality and access, as well as varied "country-specific" factors significantly affect patient experiences and outcomes. As the burden of end-stage kidney disease (ESKD) has increased globally, there has also been a growing recognition of the importance of patient involvement in determining the goals of care and decisions regarding treatment. In January 2018, KDIGO (Kidney Disease: Improving Global Outcomes) convened a Controversies Conference focused on dialysis initiation, including modality choice, access, and prescription. Here we present a summary of the conference discussions, including identified knowledge gaps, areas of controversy, and priorities for research. A major novel theme represented during the conference was the need to move away from a "one-size-fits-all" approach to dialysis and provide more individualized care that incorporates patient goals and preferences while still maintaining best practices for quality and safety. Identifying and including patient-centered goals that can be validated as quality indicators in the context of diverse health care systems to achieve equity of outcomes will require alignment of goals and incentives between patients, providers, regulators, and payers that will vary across health care jurisdictions.

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

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

Trends in the Management of Patients With Kidney Failure in Alberta, Canada (2004-2013)

BACKGROUND

Based on clinical practice guidelines, specific quality indicators are examined to assess the performance of a health care system for patients with end-stage renal disease (ESRD). We examined trends in the proportion of patients with ESRD referred late to nephrology, timing of dialysis initiation in those with chronic kidney disease, and proportion of patients with ESRD treated with pre-emptive kidney transplantation or peritoneal dialysis (PD). Design:: This was a retrospective cohort study. Setting:: The study was conducted in Alberta, Canada. Patients:: Alberta residents aged 18 years or older with incident ESRD requiring renal replacement therapy between 2004 and 2013 were included. Measurements:: Descriptive statistics, and log binomial and linear regression models were used for analysis. Methods:: We determined the proportion of patients with ESRD who did not see a nephrologist within 90 days prior to starting dialysis (late referrals) and those who were receiving PD 90 days after dialysis initiation. Among those who had been seen by a nephrologist for at least 90 days, we also assessed the proportion who initiated dialysis with estimated glomerular filtration rate (eGFR) higher than or equal to 10.5 mL/min/1.73 m2, and underwent a pre-emptive transplant. Results:: Our cohort included 5343 patients (mean age 61.8 years, 61.2% male). Over a 10-year period, there was a decrease in the proportion of late referrals (26.4% to 21.1%, P = .001). We also noted a decrease in the proportion of dialysis initiation with eGFR higher than or equal to 10.5 mL/min/1.73 m2 (21.2% to 14.7%, P < .001), with a significant increase in the proportion of patients initiating dialysis as an inpatient (38.8% to 45.2%, P = .001). There was a non-significant decrease in both the proportion of patients treated with a pre-emptive transplant and PD at 90 days over the 10-year period. Limitations:: The use of administrative data restricted the availability of clinical data regarding underlying circumstances of each quality indicator, including patient symptoms, indications for dialysis initiation, and PD eligibility.

CONCLUSIONS

We noted improvement in late referrals and early dialysis initiation over time. However, we also noted low and stable use of pre-emptive kidney transplantation and PD at 90 days, which warrants further exploration. These findings support the need for quality improvement initiatives designed to address these gaps in care and improve outcomes for patients with kidney failure.

Timing of Dialysis Initiation: What Has Changed Since IDEAL?

The optimal timing of initiation of maintenance dialysis in patients with end-stage renal disease currently is unknown. This transition period is one of exceptionally high vulnerability for patients; annual mortality rates in stage 5 chronic kidney disease through the first year of maintenance dialysis exceed 20%. The results of the Initiating Dialysis Early and Late (IDEAL) study, a randomized trial that tested the impact of dialysis initiation at two different levels of kidney function on outcomes, showed no significant difference in survival or other patient-centered outcomes between treatment groups. These data have challenged the established paradigm of using estimates of glomerular filtration as the primary guide for initiation of maintenance dialysis and illustrate the compelling need for research to optimize the high-risk transition period from chronic kidney disease to end-stage renal disease. This article reviews the findings of the IDEAL study and summarizes the evolution of research findings, updated clinical practice guidelines, and trends in dialysis initiation practices in the United States in the 6 years since the publication of the results from IDEAL. Complementary strategies to the use of estimated glomerular filtration rate to optimally time the initiation of maintenance dialysis and potentially improve patient-centered outcomes also are considered.

Variation in estimated glomerular filtration rate at dialysis initiation in children

BACKGROUND

Data guiding the timing of dialysis initiation in children are limited. We sought to determine current practice and secular trends in Canada with respect to the timing of dialysis initiation in children based on estimated glomerular filtration rate (eGFR).

METHODS

This observational study included incident chronic dialysis patients aged ≤21 years identified from the Canadian Organ Replacement Register who started dialysis in Canada between January 2001 and December 2010 at any of the nine participating Canadian centers (n = 583). Youth were categorized utilizing CKiD Schwartz eGFR into ≥10.5 (higher) or <10.5 ml/min/1.73 m² (lower) eGFR groups. Differences at dialysis initiation by facility and region were examined, and secular trends were determined.

RESULTS

Median eGFR at dialysis initiation was 8.1 (interquartile range 5.4-11.0) ml/min/1.73 m². Overall, 29 % of the patients started dialysis with an eGFR of ≥10.5 ml/min/1.73 m². The proportion of children starting with higher eGFR increased from 27.3 % in 2001 to 35.4 % in 2010 (p = 0.04) and differed by treatment facility (12-70 %; p = 0.0001). Factors associated with higher eGFR at dialysis initiation in the adjusted regression model were female sex [odds ratio (OR) 1.48; 95 % confidence interval (CI) 1.02-2.14], genetic cause of end-stage kidney disease (OR 2.77; 95 % CI 1.37-5.58) and living ≥50 km from treatment facility (OR 1.47; 95 % CI 1.01-2.14).

CONCLUSIONS

One-third of the children were found to have initiated dialysis with an eGFR ≥10.5 ml/min/1.73 m², however significant practice variation exists with respect to timing of dialysis initiation by treatment facility. More data is required to evaluate the clinical implications of this practice variation.

Geographic variation of parathyroidectomy in patients receiving hemodialysis: a retrospective cohort analysis

Background

Secondary hyperparathyroidism (SHPT) is associated with adverse outcomes in patients receiving maintenance dialysis. Parathyroidectomy is a treatment for SHPT; whether parathyroidectomy utilization varies geographically in the US is unknown.

Methods

A retrospective cohort analysis was undertaken to identify all patients aged 18 years or older who were receiving in-center hemodialysis between 2007 and 2009, were covered by Medicare Parts A and B, and had been receiving hemodialysis for at least 1 year. Parathyroidectomy was identified from inpatient claims using relevant International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes. Patient characteristics and End-Stage Renal Disease Network (a proxy for geography) were ascertained. Adjusted odds ratios for parathyroidectomy were estimated from a logistic model.

Results

A total of 286,569 patients satisfied inclusion criteria, of whom 4435 (1.5%) underwent PTX. After adjustment for a variety of patient characteristics, there was a 2-fold difference in adjusted odds of parathyroidectomy between the most- and least-frequently performing regions. Adjusted odds ratios were more than 20% higher than average in four networks, and more than 20% lower in four networks.

Conclusions

Parathyroidectomy use varies substantially by geography in the US; the factors responsible should be further investigated.

Knowledge Translation Interventions to Improve the Timing of Dialysis Initiation: Protocol for a Cluster Randomized Trial

Background:

Early initiation of chronic dialysis (starting dialysis with higher vs lower kidney function) has risen rapidly in the past 2 decades in Canada and internationally, despite absence of established health benefits and higher costs. In 2014, a Canadian guideline on the timing of dialysis initiation, recommending an intent-to-defer approach, was published.

Objective:

The objective of this study is to evaluate the efficacy and safety of a knowledge translation intervention to promote the intent-to-defer approach in clinical practice.

Design:

This study is a multicenter, 2-arm parallel, cluster randomized trial.

Setting:

The study involves 55 advanced chronic kidney disease clinics across Canada.

Patients:

Patients older than 18 years who are managed by nephrologists for more than 3 months, and initiate dialysis in the follow-up period are included in the study.

Measurements:

Outcomes will be measured at the patient-level and enumerated within a cluster. Data on characteristics of each dialysis start will be determined by linkages with the Canadian Organ Replacement Register. Primary outcomes include the proportion of patients who start dialysis early with an estimated glomerular filtration rate greater than 10.5 mL/min/1.73 m² and start dialysis in hospital as inpatients or in an emergency room setting. Secondary outcomes include the rate of change in early dialysis starts; rates of hospitalizations, deaths, and cost of predialysis care (wherever available); quarterly proportion of new starts; and acceptability of the knowledge translation materials.

Methods:

We randomized 55 multidisciplinary chronic disease clinics (clusters) in Canada to receive either an active knowledge translation intervention or no intervention for the uptake of the guideline on the timing of dialysis initiation. The active knowledge translation intervention consists of audit and feedback as well as patient- and provider-directed educational tools delivered at a comprehensive in-person medical detailing visit. Control clinics are only exposed to guideline release without active dissemination. We hypothesize that the clinics randomized to the intervention group will have a lower proportion of early dialysis starts.

Limitations:

Limitations include passive dissemination of the guideline through publication, and lead-time and survivor bias, which favors delayed dialysis initiation.

Conclusions:

If successful, this active knowledge translation intervention will reduce early dialysis starts, lead to health and economic benefits, and provide a successful framework for evaluating and disseminating future guidelines.

Trial Registration:

ClinicalTrials.gov, NCT02183987

Geovariation in Fracture Risk among Patients Receiving Hemodialysis

BACKGROUND AND OBJECTIVES

Fractures are a major source of morbidity and mortality in patients receiving dialysis. We sought to determine whether rates of fractures and tendon ruptures vary geographically.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the US Renal Data System were used to create four yearly cohorts, 2007-2010, including all eligible prevalent patients on hemodialysis in the United States on January 1 of each year. A secondary analysis comprising patients in a large dialysis organization conducted over the same period permitted inclusion of patient-level markers of mineral metabolism. Patients were grouped into 10 regions designated by the Centers for Medicare and Medicaid Services and divided by latitude into one of three bands: south, <35°; middle, 35° to <40°; and north, ≥40°. Poisson regression was used to calculate unadjusted and adjusted region-level rate ratios for events.

RESULTS

Overall, 327,615 patients on hemodialysis were included. Mean (SD) age was 61.8 (15.0) years old, 52.7% were white, and 55.0% were men. During 716,962 person-years of follow-up, 44,014 fractures and tendon ruptures occurred, the latter being only 0.3% of overall events. Event rates ranged from 5.36 to 7.83 per 100 person-years, a 1.5-fold rate difference across regions. Unadjusted region-level rate ratios varied from 0.83 (95% confidence interval, 0.81 to 0.85) to 1.20 (95% confidence interval, 1.18 to 1.23), a 1.45-fold rate difference. After adjustment for a wide range of case mix variables, a 1.33-fold variation in rates remained. Rates were higher in north and middle bands than the south (north rate ratio, 1.18; 95% confidence interval, 1.13 to 1.23; middle rate ratio, 1.13; 95% confidence interval, 1.10 to 1.17). Latitude explained 11% of variation, independent of region. A complementary analysis of 87,013 patients from a large dialysis organization further adjusted for circulating mineral metabolic parameters and protein energy wasting yielded similar results.

CONCLUSIONS

Rates of fractures vary geographically in the United States dialysis population, even after adjustment for known patient characteristics. Latitude seems to contribute to this phenomenon, but additional analyses exploring whether other factors might influence variation are warranted.

Perceptions of pediatric nephrologists regarding timing of dialysis initiation in children in Canada

BACKGROUND

Significant practice variation exists in Canada with respect to timing of dialysis initiation in children. In the absence of evidence to guide practice, physicians' perceptions may significantly influence decision-making.

OBJECTIVE

The objectives of this study are to (1) evaluate Canadian pediatric nephrologists' perceptions regarding dialysis initiation in children with chronic kidney disease (CKD) and (2) determine the factors guiding practice that may contribute to practice variation across Canada.

DESIGN

This study was a cross-sectional online survey.

SETTING

This study was done in academic pediatric nephrology centers in Canada.

PARTICIPANTS

The participants of this study are pediatric nephrologists.

MEASUREMENTS AND METHODS

An anonymous web-based survey was administered to pediatric nephrologists in Canada to evaluate perspectives and practice patterns regarding timing of dialysis initiation. We also explored the importance of estimated glomerular filtration rate (eGFR) vs. symptoms and the role of patient and provider factors influencing decisions.

RESULTS

Thirty-five nephrologists (59 %) completed the survey. Most respondents care for advanced CKD patients in a multidisciplinary clinic (86 %) and no centers have a formal policy on timing of dialysis initiation. Seventy-five percent of centers follow <20 stage 4-5 CKD patients, and 9 % follow >30 patients. Discussions about dialysis initiation are generally informal (75 %) and the decision to start is made by the nephrologist (37 %) or a team (57 %). Fifty percent agreed GFR was important when deciding when to initiate dialysis, 41 % were neutral, and 9 % disagreed. Variability exists in the threshold that nephrologists considered early (vs. late) dialysis initiation: >20 (21 %), >15 (38 %), >12 (26 %), and >10 ml/min/1.73 m(2) (12 %). Practitioners however typically start dialysis in asymptomatic patients at eGFRs of 7-9 (9 %), 10-11 (41 %), 12-14 (38 %), and 15-19 (6 %) ml/min/1.73 m(2). Patient factors important in the decision to start dialysis for >90 % of nephrologists were fatigue, >10 % weight loss, nausea, increasing missed school, and awaiting a pre-emptive transplant. Age was only a factor for 56 %.

LIMITATIONS

This study has a 59 % response rate.

CONCLUSIONS

Variability exists in Canada regarding the importance and threshold of eGFR guiding the decision as to when to start dialysis in children, whereas patient symptoms are almost universally important to pediatric nephrologists' decision-making. Additional studies evaluating outcomes of children starting dialysis earlier vs. later are needed to standardize decision-making and care for children with kidney failure.

Geographic and facility variation in initial use of non-tunneled catheters for incident maintenance hemodialysis patients

Background

Non-tunneled (temporary) hemodialysis catheters (NTHCs) are the least-optimal initial vascular access for incident maintenance hemodialysis patients yet little is known about factors associated with NTHC use in this context. We sought to determine factors associated with NTHC use and examine regional and facility-level variation in NTHC use for incident maintenance hemodialysis patients.

Methods

We analyzed registry data collected between January 2001 and December 2010 from 61 dialysis facilities within 12 geographic regions in Canada. Multi-level models and intra-class correlation coefficients were used to evaluate variation in NTHC use as initial hemodialysis access across facilities and geographic regions. Facility and patient characteristics associated with the lowest and highest quartiles of NTHC use were compared.

Results

During the study period, 21,052 patients initiated maintenance hemodialysis using a central venous catheter (CVC). This included 10,183 patients (48.3 %) in whom the initial CVC was a NTHC, as opposed to a tunneled CVC. Crude variation in NTHC use across facilities ranged from 3.7 to 99.4 % and across geographic regions from 32.4 to 85.1 %. In an adjusted multi-level logistic regression model, the proportion of total variation in NTHC use explained by facility-level and regional variation was 40.0 % and 34.1 %, respectively. Similar results were observed for the subgroup of patients who received greater than 12 months of pre-dialysis nephrology care. Patient-level factors associated with increased NTHC use were male gender, history of angina, pulmonary edema, COPD, hypertension, increasing distance from dialysis facility, higher serum phosphate, lower serum albumin and later calendar year.

Conclusions

There is wide variation in NTHC use as initial vascular access for incident maintenance hemodialysis patients across facilities and geographic regions in Canada. Identifying modifiable factors that explain this variation could facilitate a reduction of NTHC use in favor of more optimal initial vascular access.

Perceptions of prognostic risks in chronic kidney disease: a national survey

Background

Predicting the clinical trajectories of chronic kidney disease (CKD) to discern personalized care remains a complex challenge in nephrology. Understanding the appropriate risk thresholds and time frame associated with predicting risks of key outcomes (kidney failure, cardiovascular (CV) events, and death) is critical in facilitating decision-making. As part of an exploratory research and practice support needs assessment, we aimed to determine the importance of the time frames for predicting key outcomes, and to assess the perceived demand for risk prediction tools among Canadian nephrologists.

Methods

A web-based survey was developed by a pan-Canadian expert panel of practitioners. Upon pre-test for clarity and ease of completion, the final survey was nationally deployed to Canadian nephrologists. Anonymous responses were gathered over a 4-month period. The results were analyzed using descriptive statistics.

Results

One hundred eleven nephrologists responded to our survey. The majority of the respondents described prediction of events over time frames of 1–5 years as being “extremely important” or “very important” to decision-making on a 5-point Likert scale. To plan for arteriovenous fistula referral, the respondents deemed thresholds which would predict probability of kidney failure between >30 and >50 % at 1 year, as useful, while many commented that the rate of progression should be included for decision-making. Over 80 % of the respondents were not satisfied with their current ability to predict the progression to kidney failure, CV events, and death. Most of them indicated that they would value and use validated risk scores for decision-making.

Conclusions

Our national survey of nephrologists shows that the risk prediction for major adverse clinical outcomes is valuable in CKD at multiple time frames and risk thresholds. Further research is required in developing relevant and meaningful risk prediction models for clinical decision-making in patient-centered CKD care.

Electronic supplementary material

The online version of this article (doi:10.1186/s40697-015-0088-z) contains supplementary material, which is available to authorized users.

State level variations in nephrology workforce and timing and incidence of dialysis in the United States among children and adults: a retrospective cohort study

BACKGROUND

Multiple factors influence timing of dialysis initiation. The impact of supply of nephrology workforce on timing and incidence of dialysis initiation is not well known.

METHODS

We determined the number of pediatric and adult nephrologists in each state using data from the American Medical Association and American Boards of Internal Medicine and Pediatrics. We ascertained state population data from the 2010 US Census. United States Renal Data System (USRDS) data were used to determine estimated glomerular filtration rate (eGFR) at dialysis initiation and dialysis incidence for adults (≥18 years) in 2008 and children (<18 years) in 2007-2009 by state.

RESULTS

Across all states, there were a median of 3.0 (IQR 2.3 to 3.4) adult nephrologists per 100,000 adults and 0.5 (IQR 0.2 to 0.9) pediatric nephrologists per 100,000 children. The median eGFR at start of dialysis was 9.8 mL/min/1.73 m2 (IQR 7.1-13.1) in adults and 8.5 mL/min/1.73 m2 (IQR 6.2-11.4) in children. Neither the number of adult (Spearman r of 0.02 [95% CI -0.26-0.30], p = 0.88) nor pediatric (Spearman r of -0.13 [95% -0.39-0.15], p = 0.38) nephrologists per state population was associated with mean eGFR across states. The number of nephrologists per state population was associated with incident dialysis cases per state population in adults (Spearman r of 0.50 [95% CI 0.26-0.68], p = 0.0002), but not in children (Spearman r of -0.06 [95% CI -0.33-0.22], p = 0.67). In linear regression models, the association between nephrologists per state population and incident dialysis cases per state population remained statistically significant (p = 0.006) after adjustment for provider characteristics.

CONCLUSIONS

Nephrology workforce supply is aligned with demand but does not appear to be associated with timing of dialysis initiation.

Trends in Arteriovenous Fistula Use at Dialysis Initiation After Automated eGFR Reporting

The purpose of this study was to examine trends in the presence of an arteriovenous fistula (AVF) at dialysis initiation before and after eGFR reporting. All incident dialysis patients from four Canadian provinces that implemented province-wide, automated laboratory reporting of eGFR with known vascular access at dialysis initiation were included in the study (N = 25,201) from 2001 to 2010. The primary outcome was the change in proportion of patients with an AVF at dialysis initiation using an interrupted time series and adjusted multilevel logistic regression models. AVF usage at dialysis initiation decreased gradually over the study period from 19.0% to 14.6%. After implementation of automated eGFR reporting, there was attenuation in the decline in AVF usage in models adjusted for case-mix, facility, and the downward trajectory in AVF use over time. The adjusted odds ratio for initiating dialysis with an AVF 1 year post-eGFR reporting compared to pre-eGFR reporting was more pronounced in older patients (age tertile >73; OR: 1.40; 95% CI: 1.04-1.90). Laboratory-based eGFR reporting was associated with a possible attenuation in the decline of AVF at dialysis initiation and this was more pronounced in older patients.

The Canadian Society of Nephrology methods in developing and adapting clinical practice guidelines: a review

INTRODUCTION

The Canadian Society of Nephrology (CSN) was established to promote the highest quality of care for patients with renal diseases and to encourage research related to the kidney and its disorders. The CSN Clinical Practice Guideline (CPG) Committee develops guidelines with clear recommendations to influence physicians' practice and improve the health of patients with kidney disease in Canada.

REVIEW

In this review we describe the CSN process in prioritizing CPGs topics. We document the CSN experience using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. We then detail the CSN process in developing de novo CPGs and in adapting existing CPGs and developing accompanying commentaries. We also discuss challenges faced during this process and suggest solutions. Furthermore, we summarize the CSN effort in disseminating and implementing their guidelines. Additionally, we describe recent development and partnerships that allow evaluation of the effect of the CSN guidelines and commentaries.

CONCLUSION

The CSN follows a comprehensive process in identifying priority areas to be addressed in CPGs. In 2010, the CSN adopted GRADE, which enhanced the rigor and transparency of guideline development. This process focuses on systematically identifying best available evidence and carefully assessing its quality, balancing benefits and harms, considering patients' and societies' values and preferences, and when possible considering resource implications. Recent partnership allows wider dissemination and implementation among end users and evaluation of the effects of CPG and commentaries on the health of Canadians.