Treatment center and geographic variability in pre-ESRD care associate with increased mortality

Community Health Center Penetration and Kidney Care Outcomes among Low-Income, Nonelderly Adults with Kidney Failure

Key Points

Populations who experience health disparities often rely on community health centers (CHCs) for ambulatory care. Among low-income populations, higher CHC penetration is associated with greater preparedness for, and better outcomes after, kidney failure onset. Our study suggests that CHCs provide essential ambulatory care for nonelderly adults who experience kidney health disparities.

Background

In the United States, historically minoritized populations experience disproportionately high incidence of progressive kidney disease but are often unprepared for kidney failure. Owing to limited options for health care, many minoritized patients with kidney disease rely on community health centers (CHCs) for affordable ambulatory care.

Methods

We conducted a retrospective cohort study of 139,275 adults aged 18–64 years who were enrolled in Medicaid or uninsured at the time of ESKD onset during 2016–2020. We examined whether CHC penetration of the state-level low-income population was associated with ESKD incidence, process measures reflective of pre-ESKD care quality, and survival and kidney transplant waitlisting 1 year after ESKD onset. We obtained population characteristics of the 1370 Health Resources and Services Administration CHCs and 50 states (and DC) for the same period.

Results

Mean CHC penetration among low-income residents (percentage of low-income residents who were CHC patients in each state) was 36% (SD, 19%). The Northeast (census region) had the highest proportion of states with high CHC penetration, and the South had the highest proportion of states with low CHC penetration. The prevalence of diabetes mellitus, high BP, and obesity were lower in states with high versus low CHC penetration. There were no significant differences in age- and sex-standardized ESKD incidence according to CHC penetration. In individual-level analyses, higher CHC penetration was significantly associated with a higher likelihood of prolonged nephrology care (adjusted odds ratio [OR], 1.04 [95% confidence interval (CI), 1.03 to 1.05]), arteriovenous fistula or graft usage at hemodialysis initiation (OR, 1.11 [95% CI, 1.09 to 1.12]), home dialysis usage (OR, 1.04 [95% CI, 1.02 to 1.05]), and 1-year kidney transplant waitlisting (OR, 1.19 [95% CI, 1.18 to 1.21]) and ESKD survival (OR, 1.06 [95% CI, 1.04 to 1.07]).

Conclusions

Among Medicaid enrollees and uninsured adults with incident kidney failure, higher CHC penetration was associated with a lower prevalence of kidney disease risk factors and better preparedness for, and higher survival after, ESKD onset. These findings warrant additional study into the role and effect of CHCs in addressing long-standing disparities in kidney health.

Multidisciplinary Delphi consensus on challenges and key factors for an optimal care model in chronic kidney disease

BACKGROUND AND PURPOSE

Chronic kidney disease (CKD) is associated with high morbidity, burden, and resource utilization, and represents a major challenge for healthcare systems. The purpose of this study was to analyse the care patterns for these patients and to reach a consensus on the key factors that should be implemented for an optimal care model in CKD, through a multidisciplinary and integrative vision.

MATERIALS AND METHODS

A multidisciplinary panel of professionals with experience in the field of CKD was formed, composed of an advisory committee of 15 experts and an additional panel of 44 experts. Challenges and areas for improvement across the continuum of care were identified through review of scientific evidence and individual interviews with the advisory committee. Key factors for an optimal model of care in CKD were agreed and assessed using the Rand/UCLA consensus methodology (adapted Delphi), evaluating their appropriateness and necessity.

RESULTS

38 key factors were identified for an optimal CKD patient care model, organised into four challenges: (1) Development of CKD management models and increased visibility of the disease, (2) Prevention, optimisation of screening, early diagnosis and registration of CKD at all levels of care, (3) Comprehensive, multidisciplinary and coordinated monitoring, ensuring therapeutic optimisation and continuity of care, and (4) Reinforcement of CKD training for health care professionals and patients. 35 key factors were assessed by the panel as adequate and clearly necessary, and of these, 14 were considered highly imperative.

CONCLUSIONS

There is consensus on the need to prioritise CKD care at both institutional and societal levels, moving towards optimal models of CKD care based on prevention and early detection of the disease, as well as comprehensive and coordinated patient monitoring and training and awareness-raising at all levels. The key factors identified constitute a roadmap that can be implemented in the different Autonomous Communities and contribute to a significant improvement in the patient's care.

County-Level Characteristics Associated with Variation in ESKD Mortality in the United States, 2010-2018

Background

Geographic and neighborhood-level factors, such as poverty and education, have been associated with an increased risk for incident ESKD, likelihood of receiving pre-ESKD care, and likelihood of receiving a transplant. However, few studies have examined whether these same factors are associated with ESKD mortality. In this study, we examined county-level variation in ESKD mortality and identified county-level characteristics associated with this variation.

Methods

We identified 1,515,986 individuals (aged 18-84 years) initiating RRT (dialysis or transplant) between 2010 and 2018 using the United States Renal Data System. Among 2781 counties, we estimated county-level, all-cause, age-standardized mortality rates (ASMR) among patients with ESKD. We then identified county-level demographic (e.g., percent female), socioeconomic (e.g., percent unemployed), healthcare (e.g., percent without health insurance), and health behavior (e.g., percent current smokers) characteristics associated with ASMR using multivariable hierarchic linear mixed models and quantified the percentage of ASMR variation explained by county-level characteristics.

Results

County-level ESKD ASMR ranged from 45 to 1022 per 1000 person-years (PY) (mean, 119 per 1000 PY). ASMRs were highest in counties located in the Tennessee Valley and Appalachia regions, and lowest in counties located in New England, the Pacific Northwest, and Southern California. In fully adjusted models, county-level characteristics significantly associated with higher ESKD mortality included a lower percentage of Black residents (-4.94 per 1000 PY), lower transplant rate (-4.08 per 1000 PY), and higher healthcare expenditures (5.21 per 1000 PY). Overall, county-level characteristics explained 19% of variation in ESKD mortality.

Conclusions

Counties with high ESKD-related mortality may benefit from targeted and multilevel interventions that combine knowledge from a growing evidence base on the interplay between individual and community-level factors associated with ESKD mortality.

Mortality rate of end-stage kidney disease patients in Taiwan

BACKGROUND/PURPOSE

End-stage kidney disease (ESKD) is a global burden that reflects each country's unique condition. We used the National Health Insurance Research Database (NHIRD) of Taiwan to decipher changes in the mortality and international survival rates and to determine the effectiveness of the pre-end-stage renal disease care program (pre-ESRD care program) to guide future health policies for ESKD.

METHODS

We conducted a retrospective cohort analysis of the NHIRD data along with records from the catastrophic illness certificate program of ESKD patients from 2010 to 2018.

RESULTS

From 2010 to 2018, the annual dialysis-related mortality rate in Taiwan increased from 10.6 to 11.8 deaths per hundred patient-years. The mortality rate for patients below 40 years appears to be decreasing, reflecting the improved quality of care for ESKD patients. Patients above 75 years showed increasing mortality, indicating the prolonged survival and aging of the ESKD population. Patients undergoing dialysis who participated in the pre-ESRD care program had a higher post-dialysis initiation life expectancy than those who did not participate. Among the program enrollees, the post-dialysis initiation life expectancy was higher in patients who had participated for more than one year. Taiwan has one of the highest ESKD patient survival rates globally.

CONCLUSIONS

From 2010 to 2018, the reduced mortality in young patients and aging of the ESKD population might indicate that the quality of care in Taiwan for ESKD has improved. Furthermore, a better survival rate after dialysis initiation was observed in the pre-ESRD care program participants.

A Cascade of Structural Barriers Contributing to Racial Kidney Transplant Inequities

Stark racial disparities in access to and receipt of kidney transplantation, especially living donor and pre-emptive transplantation, have persisted despite decades of investigation and intervention. The causes of these disparities are complex, are inter-related, and result from a cascade of structural barriers to transplantation which disproportionately impact minoritized individuals and communities. Structural barriers contributing to racial transplant inequities have been acknowledged but are often not fully explored with regard to transplant equity. We describe longstanding racial disparities in transplantation, and we discuss contributing structural barriers which occur along the transplant pathway including pretransplant health care, evaluation, referral processes, and the evaluation of transplant candidates. We also consider the role of multilevel socio-contextual influences on these processes. We believe focused efforts which apply an equity lens to key transplant processes and systems are required to achieve greater structural competency and, ultimately, racial transplant equity.

Association of the frequency of pre-end-stage renal disease medical care with post-end-stage renal disease mortality and hospitalization

Background

Previous studies have demonstrated that early pre-end-stage renal disease (ESRD) nephrology care could improve postdialysis prognosis. However, less is known about the specific types of interventions responsible for the improved outcomes. We hypothesized that more frequent predialysis laboratory testing is associated with better postdialysis outcomes in incident ESRD patients.

Methods

In all, 23 089 patients with available outpatient laboratory tests performed during the 2-year predialysis (i.e. prelude) period were identified from a total of 52 172 American veterans with chronic kidney disease (CKD) transitioning to dialysis between October 2007 and September 2011. The associations between the frequency of combined laboratory tests, including serum creatinine, serum potassium and hemoglobin (test trio), with postdialysis mortality and hospitalization were examined in multivariable adjusted Cox and logistic regression models.

Results

When entering the 2-year prelude period, the mean age (Standard Deviation) of the patients was 66.2 (SD 11.3) years and the mean estimated glomerular filtration rate was 46.8 (SD 23.9) mL/min/1.73 m2. In all, 14% of patients had the test trio performed less than twice in 24 months and 8.9% had the trio measured more often than every other month. Over a 2.5-year median postdialysis follow-up period, 15 303 (66.3%) patients died (mortality rate 260/1000 patient-years). The adjusted hazard ratio of all-cause mortality and adjusted odds ratio of the composite of hospitalization or death associated with lab testing done >12/24 months compared with 2-≤4/24 months were 0.68 [95% confidence interval (CI) 0.65-0.73] and 0.70 (95% CI 0.62-0.79), respectively.

Conclusions

More frequent laboratory testing in patients with advanced CKD is associated with better clinical outcomes after dialysis. Further examination in clinical trials is needed before the implementation of more frequent laboratory testing in clinical practice.

Pre-ESRD Care and Mortality in Incident ESRD Patients With Multiple Myeloma

OBJECTIVES

The relationship between mortality and pre-ESRD (end-stage renal disease) nephrology care in incident ESRD patients with multiple myeloma (MM) as the primary cause of renal failure has not been examined.

MATERIALS AND METHODS

Among 439,206 incident US hemodialysis patients with MM as the primary cause of ESRD (June 1, 2005 to May 31, 2009) identified using the US Renal Data System, adjusted odds ratios (OR) for reported pre-ESRD nephrology care for ESRD due to MM (n=4561) versus other causes (n=434,645) were calculated. The association of pre-ESRD nephrology care with subsequent mortality in MM-ESRD patients was examined.

RESULTS

MM-ESRD patients were less likely to have any predialysis nephrology care in the year before initiation of dialysis (34.8% vs. 58.5%; OR=0.38; 95% confidence interval [CI], 0.34-0.43) compared with patients with ESRD due to other causes. MM-ESRD patients compared with others were more likely to have catheters on first dialysis (91.8% vs. 75.6%; OR=4.15; 95% CI, 3.54-4.86). Incident MM-ESRD patients receiving predialysis care for ≥6 months had significantly lower 1-year mortality (hazard ratio 0.89; 95% CI, 0.82-0.97 and 0.88; 95% CI, 0.80-0.96, respectively), relative to those without this care. A catheter for dialysis access was associated with a 1.6-fold increase in 1-year mortality in incident MM-ESRD (hazard ratio 1.55; 95% CI, 1.32-1.83).

CONCLUSIONS

MM-ESRD patients were less likely to have predialysis nephrology care and more likely to use catheters on first dialysis. However, predialysis care is independently associated with lower mortality in MM-ESRD patients. Predialysis care should be prioritized in MM patients approaching ESRD.

Associations between access to healthcare, environmental quality, and end-stage renal disease survival time: Proportional-hazards models of over 1,000,000 people over 14 years

Prevalence of end-stage renal disease (ESRD) in the US increased by 74% from 2000 to 2013. To investigate the role of the broader environment on ESRD survival time, we evaluated average distance to the nearest hospital by county (as a surrogate for access to healthcare) and the Environmental Quality Index (EQI), an aggregate measure of ambient environmental quality composed of five domains (air, water, land, built, and sociodemographic), at the county level across the US. Associations between average hospital distance, EQI, and survival time for 1,092,281 people diagnosed with ESRD between 2000 and 2013 (age 18+, without changes in county residence) from the US Renal Data System were evaluated using proportional-hazards models adjusting for gender, race, age at first ESRD service date, BMI, alcohol and tobacco use, and rurality. The models compared the average distance to the nearest hospital (<10, 10-20, >20 miles) and overall EQI percentiles [0-5), [5-20), [20-40), [40-60), [60-80), [80-95), and [95-100], where lower percentiles are interpreted as better EQI. In the full, non-stratified model with both distance and EQI, there was increased survival for patients over 20 miles from a hospital compared to those under 10 miles from a hospital (hazard ratio = 1.14, 95% confidence interval = 1.12-1.15) and no consistent direction of association across EQI strata. In the full model stratified by average hospital distance, under 10 miles from a hospital had increased survival in the worst EQI strata (median survival 3.0 vs. 3.5 years for best vs. worst EQI, respectively), however for people over 20 miles from a hospital, median survival was higher in the best (4.2 years) vs worst (3.4 years) EQI. This association held across different rural/urban categories and age groups. These results demonstrate the importance of considering multiple factors when studying ESRD survival and future efforts should consider additional components of the broader environment.

Racial Disparities in Nephrology Consultation and Disease Progression among Veterans with CKD: An Observational Cohort Study

BACKGROUND

Incident rates of ESRD are much higher among black and Hispanic patients than white patients. Access to nephrology care before progression to ESRD is associated with better clinical outcomes among patients with CKD. However, it is unknown whether black or Hispanic patients with CKD experience lower pre-ESRD nephrology consultation rates compared with their white counterparts, or whether such a disparity contributes to worse outcomes among minorities.

METHODS

We assembled a retrospective cohort of patients with CKD who received care through the Veterans Health Administration from 2003 to 2015, focusing on individuals with incident CKD stage 4 who had an initial eGFR≥60 ml/min per 1.73 m² followed by two consecutive eGFRs<30 ml/min per 1.73 m². We repeated analyses among individuals with incident CKD stage 3. Outcomes included nephrology provider referral, nephrology provider visit, progression to CKD stage 5, and mortality.

RESULTS

We identified 56,767 veterans with CKD stage 4 and 640,704 with CKD stage 3. In both cohorts, rates of nephrology referral and visits were significantly higher among black and Hispanic veterans than among non-Hispanic white veterans. Despite this, both black and Hispanic patients experienced faster progression to CKD stage 5 compared with white patients. Black patients with CKD stage 4 experienced slightly lower mortality than white patients, whereas black patients with CKD stage 3 had a small increased risk of death.

CONCLUSIONS

Black or Hispanic veterans with CKD are more likely than white patients to see a nephrologist, yet are also more likely to suffer disease progression. Biologic and environmental factors may play a bigger role than nephrology consultation in driving racial disparities in CKD progression.

Pre-Dialysis Visits to a Nephrology Department and Major Cardiovascular Events in Patients Undergoing Dialysis

Background and Objectives

Pre-dialysis care by a nephrology out-patient department (OPD) may affect the outcomes of patients who ultimately undergo maintenance dialysis. This study examined the effect of pre-dialysis care by a nephrology OPD on the incidence of one-year major cardiovascular events after initiation of dialysis.

Design, Setting Participants, & Measurements

The study consisted of Taiwanese patients with chronic kidney disease (CKD) who commenced dialysis from 2006 to 2008. The number of nephrology OPD visits during the critical care period (within 6 months of initiation of dialysis) and the early care period (6–36 months before initiation of dialysis) were analyzed. The primary outcome measure was one-year major cardiovascular events.

Results

A total of 1191 CKD patients who initiated dialysis from 2006 to 2008 were included. Binary logistic regression showed that patients with ≧3 visits during the critical care period and those with ≧11 visits during the early care period had fewer composite major cardiovascular events than those with 0 visits. Patients with early referral are less likely to experience composite major cardiovascular events than those with late referral, with aOR 0.574 (95% CI = 0.43–0.77, P<0.001). Patients with both ≧3 visits during critical care period and ≧11 visits during early care period were less likely to experience composite major cardiovascular events (aOR = 0.25, 95% CI = 0.16–0.39, P < 0.001).

Conclusions

Patients with adequate pre-dialysis nephrology OPD visits, not just early referral, may had fewer one-year composite major cardiovascular events after initiation of dialysis. This information may be important to medical care providers and public health policy makers in their efforts to improve the well-being of CKD patients.

Establishment of a renal supportive care program: Experience from a rural community hospital in Taiwan

Renal supportive care (RSC) denotes a care program dedicated for patients with acute, chronic renal failure, and end-stage renal disease (ESRD), aiming to offer maximal symptom relief and optimize patients' quality of life. The uncertainty of prognosis for patients with chronic kidney disease and ESRD, the sociocultural issues inherent to the Taiwanese society, and the void of structured and practical RSC pathway, contributes to the underrecognition and poor utilization of RSC. Taiwanese patients rarely receive information regarding RSC as part of a standardized care and are not commonly offered this option. In National Taiwan University Hospital Jinshan branch, we started a RSC subprogram, supported by the community-based palliative/hospice care main program. We focused on understanding the need and providing the choice of RSC to suitable candidates. A three-step and four-phase protocol was designed and implemented to identify appropriate patients and to enhance the applicability of the RSC. We harnessed family visit and home-based family meeting as a vehicle to understand the patients' preferences, to discover what ESRD patients and their family value most, and to introduce the option of RSC. In the current review, we described our pilot experience of establishing a RSC program in Taiwan, and discuss its potential advantage.

Nephrology care prior to end-stage renal disease and outcomes among new ESRD patients in the USA

Background

Longer nephrology care before end-stage renal disease (ESRD) has been linked with better outcomes.

Methods

We investigated whether longer pre-end-stage renal disease (ESRD) nephrology care was associated with lower mortality at both the patient and state levels among 443 761 incident ESRD patients identified in the USA between 2006 and 2010.

Results

Overall, 33% of new ESRD patients had received no prior nephrology care, while 28% had received care for >12 months. At the patient level, predictors of >12 months of nephrology care included having health insurance, white race, younger age, diabetes, hypertension and US region. Longer pre-ESRD nephrology care was associated with lower first-year mortality (adjusted hazard ratio = 0.58 for >12 months versus no care; 95% confidence interval 0.57–0.59), higher albumin and hemoglobin, choice of peritoneal dialysis and native fistula and discussion of transplantation options. Living in a state with a 10% higher proportion of patients receiving >12 months of pre-ESRD care was associated with a 9.3% lower relative mortality rate, standardized for case mix (R² = 0.47; P < 0.001).

Conclusions

This study represents the largest cohort of incident ESRD patients to date. Although we did not follow patients before ESRD onset, our findings, both at the individual patient and state levels, reflect the importance of early nephrology care among those with chronic kidney disease.

Interstate Variation in Receipt of Nephrologist Care in US Patients Approaching ESRD: Race, Age, and State Characteristics

BACKGROUND AND OBJECTIVES

Although multiple factors influence access to nephrologist care in patients with CKD stages 4-5, the geographic determinants within the United States are incompletely understood. In this study, we examined interstate differences in nephrologist care among patients approaching ESRD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This national, population-based analysis included 373,986 adult patients from the US Renal Data System, who initiated maintenance dialysis between 2005 and 2009. Multilevel logistic regression was used to examine interstate variation in nephrologist care (≥12 months before ESRD) for overall and four race-age subpopulations (black or white and older or younger than 65 years).

RESULTS

The average state-level probability of having received nephrologist care in all states combined was 28.8% (95% confidence interval, 25.2% to 32.7%) overall and was lowest (24.3%) in the younger black subpopulation. Even at these lower levels, state-level probabilities varied considerably across states in overall and subpopulations (all P<0.001). Overall, excluding the states in the upper and lower five percentiles, the remaining states had a probability of receiving care that varied from 18.5% to 41.9%. The lower probability of receiving nephrologist care for blacks than whites among younger patients noted in most states was attenuated in older patients. Geographically, all New England states and most Midwest states had higher than average probability, whereas most Middle Atlantic and Southern states had lower than average probability. After controlling for patient factors, three state-characteristic categories, including general healthcare access measured by percentage of uninsured persons and Medicaid program performance scores, preventive care measured by percentage of receiving recommended preventive care, and socioeconomic status, contributed 55%-66% of interstate variation.

CONCLUSIONS

Patients living in states with better health service and socioeconomic characteristics were more likely to receive predialysis nephrologist care. The reported national black-white difference in nephrologist care was primarily driven by younger black patients being the least likely to receive care.

Geographic variation and neighborhood factors are associated with low rates of pre-end-stage renal disease nephrology care

Geographic variation of pre-end-stage renal disease (pre-ESRD) nephrology care has not been studied across the United States. Here we sought to identify geographic differences in pre-ESRD care, assess for county-level geographic and sociodemographic risk factors, and correlate with patient outcomes using facility-level mortality. Patients from 5387 dialysis facilities across the United States from 2007 to 2010 were included from the Dialysis Facility Report. Marginal generalized estimating equations were used for modeling with geographic cluster analysis to detect clusters of facilities with low rates of pre-ESRD care. On average, 67% of patients received pre-ESRD care in the United States but with significant variability across regions ranging from 3 to 99%. Five geographic clusters of facilities with low rates of pre-ESRD care were the metropolitan areas of San Francisco, Los Angeles, Chicago, Miami, and Baltimore, along with Southern states along the Mississippi River. Dialysis facilities with the lowest rates of pre-ESRD care were more likely to be located in urban counties with high African-American populations and low educational attainment. A 10% higher proportion of patients receiving pre-ESRD care was associated with 1.3% lower patient mortality as reflected by facility-level mortality. Thus, geographic and sociodemographic factors can be used to design quality improvement initiatives to increase access to nephrology care nationwide and improve patient outcomes.

Sociodemographic and geographic predictors of quality of care in United States patients with end-stage renal disease due to lupus nephritis

OBJECTIVE

To describe end-stage renal disease (ESRD) quality of care (receipt of pre-ESRD nephrology care, access to kidney transplantation, and placement of permanent vascular access for dialysis) in US patients with ESRD due to lupus nephritis (LN-ESRD) and to examine whether quality measures differ by patient sociodemographic characteristics or US region.

METHODS

National surveillance data on patients in the US in whom treatment for LN-ESRD was initiated between July 2005 and September 2011 (n = 6,594) were analyzed. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (95% CIs) were determined for each quality measure, according to sociodemographic factors and US region.

RESULTS

Overall, 71% of the patients received nephrology care prior to ESRD. Black and Hispanic patients were less likely than white patients to receive pre-ESRD care (OR 0.73 [95% CI 0.63-0.85] and OR 0.73 [95% CI 0.60-0.88], respectively) and to be placed on the kidney transplant waitlist within the first year after the start of ESRD (HR 0.78 [95% CI 0.68-0.91] and HR 0.82 [95% CI 0.68-0.98], respectively). Those with Medicaid (HR 0.51 [95% CI 0.44-0.58]) or no insurance (HR 0.36 [95% CI 0.29-0.44]) were less likely than those with private insurance to be placed on the waitlist. Only 24% had a permanent vascular access, and placement was even less likely among the uninsured (OR 0.62 [95% CI 0.49-0.79]). ESRD quality-of-care measures varied 2-3-fold across regions of the US, with patients in the Northeast and Northwest generally having higher probabilities of adequate care.

CONCLUSION

LN-ESRD patients have suboptimal ESRD care, particularly with regard to placement of dialysis vascular access. Minority race/ethnicity and lack of private insurance are associated with inadequate ESRD care. Further studies are warranted to examine multilevel barriers to, and develop targeted interventions to improve delivery of, care among patients with LN-ESRD.

Confounders of mortality and hospitalization rate calculations for profit and nonprofit dialysis facilities: analytic augmentation

BACKGROUND

Patient outcomes have been compared on the basis of the profit status of the dialysis provider (for-profit [FP] and not-for-profit [NFP]). In its annual report, United States Renal Data System (USRDS) provides dialysis provider level death and hospitalization rates adjusted by age, race, sex, and dialysis vintage; however, recent analyses have suggested that other variables impact these outcomes. Our current analysis of hospitalization and mortality rates of hemodialysis patients included adjustments for those used by the USRDS plus other potential confounders: facility geography (end-stage renal disease network), length of facility ownership, vascular access at first dialysis session, and pre-dialysis nephrology care.

METHODS

We performed a provider level, retrospective analysis of 2010 hospitalization and mortality rates among US hemodialysis patients exclusively using USRDS sources. Crude and adjusted incidence rate ratios (IRRs) were calculated using the 4 standard USRDS patient factors plus the 4 potential confounders noted above.

RESULTS

The analysis included 366,011 and 34,029 patients treated at FP and NFP facilities, respectively. There were statistical differences between the cohorts in geography, facility length of ownership, vascular access, and pre-dialysis nephrology care (p < 0.001), as well as age (p < 0.01), race (p < 0.001), and vintage (p < 0.001), but not sex (p = 0.12). When using standard USRDS adjustments, hospitalization and mortality rates for FP and NFP facilities were most disparate, favoring the NFP facilities. Rates were most similar between providers when adjustments were made for each of the 8 factors. With the FP IRR as the referent (1.0), the hospitalization IRR for NFP facilities was 1.00 (95% confidence interval [CI] 0.97-1.02; p = 0.69), while the NFP mortality IRR was 1.01 (95% CI 0.97-1.05; p = 0.64).

CONCLUSIONS

These data suggest there is no difference in mortality and hospitalization rates between FP and NFP dialysis clinics when appropriate statistical adjustments are made.

Association of increased travel distance to dialysis units with the risk of anemia in rural chronic hemodialysis elderly

Geographic remoteness has been found to influence health-related outcomes negatively. As reported in the literature, rural dialysis patients have a higher risk of mortality with increasing travel distance to dialysis units. However, few studies have focused on the impact of travel distances on the development of dialysis complications. We utilized a prospectively collected chronic hemodialysis patient cohort from a rural regional hospital for analysis. Data on demographics, comorbidities, and serum laboratory results were obtained. Correlation analyses between travel distance to dialysis units and dialysis complications were conducted, and significantly correlated parameters were entered into multivariate logistic regression models to determine their exact associations. A total of 46 rural chronic hemodialysis patients were enrolled, with an average age higher than others in the literature. Significant correlation was found between travel distance and serum hemoglobin levels (R(2) = -0.34, P value = 0.029). Multivariate logistic regression found that every 1 km increase in travel distance was associated with an increased risk of anemia (hemoglobin <9 g/dL) (odds ratio 1.46; P value = 0.01). Sensitivity analyses further showed that the associated risk was partially attenuated by serum albumin (odds ratio 1.83; P value = 0.07) and ferritin (odds ratio 1.39; P value = 0.08) levels. This is the first study to demonstrate the association between increased travel distance to dialysis units and the risk of anemia in chronic dialysis patients, especially elderly. Malnutrition, inflammation, and atherosclerosis syndrome could be partially responsible for the observed association. Further research is required to confirm our findings.

State medicaid coverage, ESRD incidence, and access to care

The proportion of low-income nonelderly adults covered by Medicaid varies widely by state. We sought to determine whether broader state Medicaid coverage, defined as the proportion of each state's low-income nonelderly adult population covered by Medicaid, associates with lower state-level incidence of ESRD and greater access to care. The main outcomes were incidence of ESRD and five indicators of access to care. We identified 408,535 adults aged 20-64 years, who developed ESRD between January 1, 2001, and December 31, 2008. Medicaid coverage among low-income nonelderly adults ranged from 12.2% to 66.0% (median 32.5%). For each additional 10% of the low-income nonelderly population covered by Medicaid, there was a 1.8% (95% confidence interval, 1.0% to 2.6%) decrease in ESRD incidence. Among nonelderly adults with ESRD, gaps in access to care between those with private insurance and those with Medicaid were narrower in states with broader coverage. For a 50-year-old white woman, the access gap to the kidney transplant waiting list between Medicaid and private insurance decreased by 7.7 percentage points in high (>45%) versus low (<25%) Medicaid coverage states. Similarly, the access gap to transplantation decreased by 4.0 percentage points and the access gap to peritoneal dialysis decreased by 3.8 percentage points in high Medicaid coverage states. In conclusion, states with broader Medicaid coverage had a lower incidence of ESRD and smaller insurance-related access gaps.

The association between geographic proximity to a dialysis facility and use of dialysis catheters

BACKGROUND

Residing remotely from health care resources appears to impact quality of care delivery. It remains unclear if there are differences in vascular access based on distance of one's residence to dialysis centre at time of dialysis initiation, and whether region or duration of pre-dialysis care are important effect modifiers.

METHODS

We studied the association of distance from a patients' residence to the nearest dialysis centre and central venous catheter (CVC) use in an observational study of 26,449 incident adult dialysis patients registered in the Canadian Organ Replacement Registry between 2000-2009. Multivariate logistic regression was used to assess the association between distance in tertiles and CVC use, adjusted for patient demographics and comorbidities. Geographic region and duration of pre-dialysis care were examined as potential effect modifiers.

RESULTS

Eighty percent of patients commenced dialysis with a CVC. Incident CVC use was highest among those living > 20 km from the dialysis centre (OR 1.29 (1.24-1.34)) compared to those living < 5 km from centre. The length of pre-dialysis care and geographic region were significant effect modifiers; among patients residing in the furthest tertile (>20 km) from the nearest dialysis centre, incident CVC use was more common with shorter length of pre-dialysis care (< 1 year) and residence in central regions of the country.

CONCLUSION

Residing further from a dialysis centre is associated with increased CVC use, an effect modified by shorter pre-dialysis care and the geographic region of the country. Efforts to reduce geographical disparities in pre dialysis care may decrease CVC use.

Pre-end-stage renal disease care not associated with dialysis facility neighborhood poverty in the United States

BACKGROUND

Receipt of nephrology care prior to end-stage renal disease (ESRD) is a strong predictor of decreased mortality and morbidity, and neighborhood poverty may influence access to care. Our objective was to examine whether neighborhood poverty is associated with lack of pre-ESRD care at dialysis facilities.

METHODS

In a multi-level ecological study using geospatially linked 2007-2010 Dialysis Facility Report and 2006-2010 American Community Survey data, we examined whether high neighborhood poverty (≥20% of households in census tract living below poverty) was associated with dialysis facility-level lack of pre-ESRD care (percentage of patients with no nephrology care prior to dialysis start) in mixed-effects models, adjusting for facility and neighborhood confounders and allowing for neighborhood and regional random effects.

RESULTS

Among the 5,184 facilities examined, 1,778 (34.3%) were located in a high-poverty area. Lack of pre-ESRD care was similar in poverty areas (30.8%) and other neighborhoods (29.6%). With adjustment, the absolute increase in percentage of patients at a facility with no pre-ESRD care associated with facility location in a poverty area versus other neighborhood was only 0.08% (95% CI -1.32, 1.47; p = 0.9). Potential effect modification by race and income inequality was detected.

CONCLUSION

Despite previously reported detrimental effects of neighborhood poverty on health, facility neighborhood poverty was not associated with receipt of pre-ESRD care, suggesting no need to target interventions to increase access to pre-ESRD care at facilities in poorer geographic areas.

Geographic and facility-level variation in the use of peritoneal dialysis in Canada: a cohort study

BACKGROUND

Peritoneal dialysis is associated with similar survival and similar improvement in quality of life and is less costly compared with in-centre hemodialysis. We examined facility and geographic variation in the use of peritoneal dialysis in Canada.

METHODS

We analyzed data from the Canadian Organ Replacement Register for the period January 2001 to December 2010. We identified patients for whom peritoneal dialysis was the primary modality at 90 days after initiation of dialysis. We used multilevel models to evaluate variation in use of peritoneal dialysis by facility and geographic region.

RESULTS

We analyzed data for 31 778 incident dialysis patients at 56 facilities in 13 geographic regions across Canada. Use of peritoneal dialysis at 90 days varied considerably across geographic regions (range 19.8%-36.1%) and declined over time, from 28.8% in 2001 to 22.5% in 2010. After adjustment for case mix and facility-level quality indicators, 9.3% and 3.4% of the variability was attributable to facility and geographic factors, respectively. In adjusted models, there was a substantial difference between geographic regions with the lowest and highest peritoneal dialysis use (odds ratio for high use 1.51, 95% confidence interval [CI] 1.33-1.73 v. odds ratio for low use 0.69, 95% CI 0.60-0.79).

INTERPRETATION

In Canada, substantial variability in the use of peritoneal dialysis attributable to facility and geographic region was not explained by differences in patient case mix. An opportunity exists to optimize use of this cost-effective therapy through changes in policy and standardization of criteria for initiation of peritoneal dialysis.

Characteristics and performance of minority-serving dialysis facilities

OBJECTIVE

To examine the structure, processes, and outcomes of American dialysis facilities that predominantly treat racial-ethnic minority patients.

DATA SOURCES/STUDY SETTING

Secondary analysis of data from all patients who initiated dialysis during 2005-2008 in the United States.

STUDY DESIGN

In this retrospective cohort study, we examined the associations of the racial-ethnic composition of the dialysis facility with facility-level survival and achievement of performance targets for anemia and dialysis adequacy.

DATA COLLECTION/EXTRACTION METHODS

We obtained dialysis facility- and patient-level data from the national data registry of patients with end-stage renal disease. We linked these data with clinical performance measures from the Centers for Medicare and Medicaid Services.

PRINCIPAL FINDINGS

Overall, minority-serving facilities were markedly larger, more often community based, and less likely to offer home dialysis than facilities serving predominantly white patients. A significantly higher proportion of minority-serving dialysis facilities exhibited worse than expected survival as compared with facilities serving predominantly white patients (p < .001 for each). However, clinical performance measures for anemia and dialysis adequacy were similar across minority-serving status.

CONCLUSIONS

While minority-serving facilities generally met dialysis performance targets mandated by Medicare, they exhibited worse than expected patient survival.

Perceptions and use of the national kidney foundation KDOQI guidelines: a survey of U.S. renal healthcare providers

Background

The National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (KDOQI) developed guidelines to care for patients with chronic kidney disease (CKD). While these are disseminated through the NKF’s website and publications, the guidelines’ usage remains suboptimal. The KDOQI Educational Committee was formed to identify barriers to guideline implementation, determine provider and patient educational needs and develop tools to improve care of patients with CKD.

Methods

An online survey was conducted from May to September 2010 to evaluate renal providers’ familiarity, current use of and attitudes toward the guidelines and tools to implement the guidelines.

Results

Most responders reported using the guidelines often and felt that they could be easily implemented into clinical practice; however, approximately one-half identified at least one barrier. Physicians and physician extenders most commonly cited the lack of evidence supporting KDOQI guidelines while allied health professionals most commonly listed patient non-adherence, unrealistic guideline goals and provider time-constraints. Providers thought that the guidelines included too much detail and identified the lack of a quick resource as a barrier to clinical implementation. Most were unaware of the Clinical Action Plans.

Conclusions

Perceived barriers differed between renal clinicians and allied health professionals; educational and implementation tools tailored for different providers are needed.

Survival in dialysis patients is different between patients with diabetes as primary renal disease and patients with diabetes as a co-morbid condition

AIMS/HYPOTHESIS

A previous study in Dutch dialysis patients showed no survival difference between patients with diabetes as primary renal disease and those with diabetes as a co-morbid condition. As this was not in line with our hypothesis, we aimed to verify these results in a larger international cohort of dialysis patients.

METHODS

For the present prospective study, we used data from the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry. Incident dialysis patients with data on co-morbidities (n = 15,419) were monitored until kidney transplantation, death or end of the study period (5 years). Cox regression was performed to compare survival for patients with diabetes as primary renal disease, patients with diabetes as a co-morbid condition and non-diabetic patients.

RESULTS

Of the study population, 3,624 patients (24%) had diabetes as primary renal disease and 1,193 (11%) had diabetes as a co-morbid condition whereas the majority had no diabetes (n = 10,602). During follow-up, 7,584 (49%) patients died. In both groups of diabetic patients mortality was higher compared with the non-diabetic patients. Mortality was higher in patients with diabetes as primary renal disease than in patients with diabetes as a co-morbid condition, adjusted for age, sex, country and malignancy (HR 1.20, 95% CI 1.10, 1.30). An analysis stratified by dialysis modality yielded similar results.

CONCLUSIONS/INTERPRETATION

Overall mortality was significantly higher in patients with diabetes as primary renal disease compared with those with diabetes as a co-morbid condition. This suggests that survival in diabetic dialysis patients is affected by the extent to which diabetes has induced organ damage.

Regional variation in the incidence of dialysis-requiring AKI in the United States

BACKGROUND AND OBJECTIVES

Little is known about geographic differences in the incidence of AKI. The objective of this study was to determine if regional variation exists in the population incidence of dialysis-requiring AKI in the United States.

DESIGN, SETTING, PARTICIPANTS, & METHODS

Data from the Nationwide Inpatient Sample, a US nationally representative sample of hospitalizations, were used to determine the incidence rates of dialysis-requiring AKI between 2007 and 2009 among the four US Census-designated regions. Cases were identified using validated discharge codes. Poisson regression models were used to estimate overall regional rates, accounting for the data's sampling scheme.

RESULTS

In 2007-2009, the population incidence rates of dialysis-requiring AKI differed across the four Census-designated regions (P=0.04). Incidence was highest in the Midwest (523 cases/million person-yr, 95% confidence interval=483 to 568) and lowest in the Northeast (457 cases/million person-yr, 95% confidence interval=426 to 492). The pattern of regional variation in the incidence of dialysis-requiring AKI was not the same as the pattern of regional variation in the incidence of renal replacement therapy-requiring ESRD (obtained from the US Renal Data System). In-hospital mortality associated with dialysis-requiring AKI differed across the four regions, with the highest case fatality in the Northeast (25.9%) and the lowest case fatality in the Midwest (19.4%).

CONCLUSIONS

Significant regional variation exists in the population incidence of dialysis-requiring AKI in the United States, and additional investigation is warranted to uncover potential causes behind these geographic differences.

Patient care staffing levels and facility characteristics in U.S. hemodialysis facilities

BACKGROUND

Higher numbers of registered nurses (RNs) per patient have been associated with improved patient outcomes in acute-care facilities. Variation in and associations of patient care staffing levels and hemodialysis facility characteristics have not been examined previously.

STUDY DESIGN

Cross-sectional study using Poisson regression to examine associations between patient care staffing levels and hemodialysis facility characteristics.

SETTING & PARTICIPANTS

4,800 US hemodialysis facilities in the 2009 Centers for Medicare & Medicaid (CMS) End-Stage Renal Disease Annual Facility Survey (CMS-2744 form).

PREDICTORS

Facility characteristics, including profit status, freestanding status, chain affiliation, and geographic region, adjusted for facility size, capacity, functional type, and urbanicity.

OUTCOMES

Patient care staffing levels, including ratios of RNs, licensed practical nurses (LPNs), patient care technicians (PCTs), composite staff (RN + LPN + PCT), social workers, and dietitians to in-center hemodialysis patients.

RESULTS

After adjusting for background facility characteristics, ratios of RNs and LPNs to patients were 35% (P < 0.001) and 42% (P < 0.001) lower, respectively, but the PCT to patient ratio was 16% (P < 0.001) higher in for-profit than nonprofit facilities (rate ratios of 0.65 [95% CI, 0.63-0.68], 0.58 [95% CI, 0.51-0.65], and 1.16 [95% CI, 1.12-1.19], respectively). Regionally, compared to the Northeast, the adjusted RN to patient ratio was 14% (P < 0.001) lower in the Midwest, 25% (P < 0.001) lower in the South, and 18% (P < 0.001) lower in the West. Even after additional adjustments, the large for-profit chains had significantly lower RN and LPN to patient ratios than the largest nonprofit chain, but a significantly higher PCT to patient ratio. Overall composite staffing levels also were lower in for-profit and chain-affiliated facilities. The patterns hold when hospital-based units were excluded.

LIMITATIONS

Nursing hours were not available. Two part-time staff were counted as one full-time equivalent, which may not always be accurate.

CONCLUSIONS

The significant variation in patient care staffing levels and its associations with facility characteristics warrants inclusion in future large-scale hemodialysis outcomes studies. End-stage renal disease networks and hemodialysis facilities should attend to quality assurance and performance improvement initiatives that maximize licensed nurse staffing levels in hemodialysis facilities.

The associations between race and geographic area and quality-of-care indicators in patients approaching ESRD

BACKGROUND AND OBJECTIVES

Pre-ESRD care is an important predictor of outcomes in patients undergoing long-term dialysis. This study examined the extent of variation in receiving pre-ESRD care and black-white disparities across urban and rural counties.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Participants were 404,622 non-Hispanic white and black patients aged >18 years who began dialysis between 2005 and 2010 and resided in 3076 counties from the U.S. Renal Data System. The counties were grouped into large metropolitan, medium/small metropolitan, suburban, and rural counties. Pre-ESRD care indicators included receipt of nephrologist care at least 6 or 12 months before ESRD, dietitian care, use of arteriovenous fistula at first outpatient dialysis session, and use of erythropoiesis-stimulating agents (ESAs) in patients with hemoglobin level < 10 g/dl.

RESULTS

Large metropolitan and rural counties had lower percentages of patients who received pre-ESRD nephrologist care (25.7% and 26.9% for nephrologist care > 12 months), compared with the higher percentage in medium/small metropolitan counties (31.6%; both P<0.001). For both races, nonmetropolitan patients had poorer access to dietitian care and lower ESA use than metropolitan patients. Consistently in all four geographic areas, black patients received less care than their white counterparts. The unadjusted odds ratios of black versus white patients in receiving nephrologist care for >12 months before ESRD were 0.66 (95% confidence interval [CI], 0.61-0.72) in large metropolitan counties and 0.79 (95% CI, 0.69-0.90) in rural counties. The patterns remained, albeit attenuated, after adjustment for patient factors.

CONCLUSIONS

The receipt of pre-ESRD care, with blacks receiving less care, varies among geographic areas defined by urban/rural characteristics.

Form CMS-2728 data versus erythropoietin claims data: implications for quality of care studies

Medical Evidence Report Form CMS-2728 data is frequently used to study US dialysis patients, but the validity of these data have been called into question. We compared predialysis erythropoietin use as recorded on Form CMS-2728 with claims data as part of an assessment of quality of care among hemodialysis patients. Medicare claims were linked to Form CMS-2728 data for 18,870 patients. Dialysis patients, 67 years old or older, who started dialysis from 1 June 2005 to 31 May 2007 were eligible. Logistic and multivariate regressions were used to compare the use of either Form CMS-2728 or the corresponding claims data to predict mortality and the probability of meeting target hemoglobin levels. The sensitivity, specificity, and kappa coefficient for the predialysis erythropoietin indicator were 58.0%, 78.4%, and 0.36, respectively. Patients with a predialysis erythropoietin claim were less likely to die compared with patients without a claim (odds ratio = 0.80 and 95% confidence interval = 0.74-0.87), but there was no relationship observed between predialysis care and death using only Form CMS-2728 predictors. At the facility level, a predialysis erythropoietin claim was associated with a 0.085 increase in the rate of meeting target hemoglobin levels compared with patients without a claim (p = 0.041), but no statistically significant relationship was observed when using the Form CMS-2728 indicators. The agreement between Form CMS-2728 and claims data is poor and discordant results are observed when comparing the use of these data sources to predict health outcomes. Facilities with higher agreement between the two data sources may provide greater quality of care.

Geographic variation in HMG-CoA reductase inhibitor use in dialysis patients

BACKGROUND

Despite uncertainty about their effectiveness in chronic dialysis patients, statin use has increased in recent years. Little is known about the demographic, clinical, and geographic factors associated with statin exposure in end-stage renal disease (ESRD) patients.

OBJECTIVE

To analyze the demographic, clinical, and geographic factors associated with use of statins among chronic dialysis patients.

DESIGN

Cross-sectional analysis.

SETTING

Prevalent dialysis patients across the U.S.

PARTICIPANTS

55,573 chronic dialysis patients who were dually eligible for Medicaid and Medicare services during the last four months of 2005.

METHODS

Using Medicaid prescription drug claims and United States Renal Data System core data, we examined demographics, comorbid conditions, and state of residence using hierarchical logistic regression models to determine their associations with statin use.

INTERVENTION

Prescription for a statin.

OUTCOME MEASURES

Factors associated with a prescription for a statin.

RESULTS

Statin exposure was significantly associated with older age, female sex, Caucasian (versus African-American) race, body mass index, use of self-care dialysis, diabetes, and comorbidity burden. Moreover, there was substantial state-by-state variation in statin use, with a greater than 2.3-fold difference in adjusted odds ratios between the highest- and lowest-prescribing states.

CONCLUSIONS

Among publicly insured chronic dialysis patients, there were marked differences between states in the use of HMG-CoA reductase inhibitors above and beyond patient characteristics. This suggests substantial clinical uncertainty about the utility of these medications. Understanding how such regional variations impact patient care in this high-risk population is an important focus for future work.

Efficacy of an internet-based tool for improving physician knowledge of chronic kidney disease: an observational study

Background

Early recognition and management of chronic kidney disease (CKD) are associated with better outcomes. Internal medicine residency should prepare physicians to diagnose and manage CKD.

Methods

To examine whether residency training and program characteristics were associated with CKD knowledge and investigate the effectiveness of an internet-based training module in improving CKD knowledge, we analyzed data from CKD training modules administered annually to U.S. internal medicine residents from July 1, 2005 to June 30, 2009. Baseline CKD knowledge was assessed using pre-tests. The modules’ effectiveness was evaluated by post-tests. Comparisons were performed using X² tests and paired t-tests.

Results

Of 4,702 residents, 38%, 33%, and 29% were program year (PGY)-1, PGY-2, and PGY-3, respectively. Baseline CKD knowledge was poor, with mean pre-test scores of 45.1-57.0% across the four years. The lowest pre-test performance was on CKD recognition. Pre-test scores were better with higher training levels (P-trend < 0.001 except 2005–2006 [P-trend = 0.35]). Affiliation with a renal fellowship program or program location within a region of high end-stage kidney disease prevalence was not associated with better baseline CKD knowledge. Completion of the CKD module led to significant improvements from pre- to post-test scores (mean improvement 27.8% [SD: 21.3%] which were consistent from 2005 to 2009.

Conclusions

Knowledge of diagnosis and management of CKD improves during residency training but remains poor among graduating residents. Web-based training can be effective in educating physicians on CKD-related issues. Studies are needed to determine whether knowledge gained from such an intervention translates to improved care of CKD patients.

High one year mortality in adults with sickle cell disease and end-stage renal disease

Adequate pre-dialysis care reduces mortality among end-stage renal disease (ESRD) patients. We tested the hypothesis that individuals with ESRD due to sickle cell disease (SCD-ESRD) receiving pre-ESRD care have lower mortality compared to individuals without pre-ESRD care. We examined the association between mortality and pre-ESRD care in incident SCD-ESRD patients who started haemodialysis between 1 June, 2005 and 31 May, 2009 using data provided by the Centers for Medicare and Medicaid Services (CMS). SCD-ESRD was reported for 410 (0·1%) of 442 017 patients. One year after starting dialysis, 108 (26·3%) patients with incident ESRD attributed to SCD died; the hazard ratio (HR) for mortality among patients with SCD-ESRD compared to those without SCD as the primary cause of renal failure was 2·80 (95% confidence interval [CI] 2·31-3·38). Patients with SCD-ESRD receiving pre-dialysis nephrology care had a lower death rate than those with SCD-ESRD who did not receive pre-dialysis nephrology care (HR = 0·67, 95% CI 0·45-0·99). The one-year mortality rate following an ESRD diagnosis was almost three times higher in individuals with SCD when compared to those without SCD but with ESRD and could be attenuated by pre-dialysis nephrology care.

Epidemiology, geography and chronic kidney disease

PURPOSE OF REVIEW

Geographic variation in the occurrence and outcomes of chronic kidney disease (CKD) is major area of study in epidemiology and health services and outcomes research. Geographic attributes may be as diverse as the physical, socioeconomic, and medical care characteristics of an environment. This review summarizes the recent literature pertaining to geographic risk factors and CKD.

RECENT FINDINGS

Studies have reported on the association between CKD and physical attributes of place (ambient temperature and altitude), the impact of disasters on CKD populations, new diseases characterized by regional localization, national variations in CKD incidence and prevalence, regional variation in end-stage renal disease incidence, residential mobility and CKD risk factors, and geographic variations in CKD care. The emerging role of tools for geospatial studies - including multilevel analytical designs, which reduce the likelihood of an ecologically biased inference, and geographic information systems, which allow the simultaneous linkage, analysis, and mapping of geospatial data - is illustrated by these studies.

SUMMARY

Our understanding of the occurrence and outcomes of CKD will continue to be expanded and deepened by the explicit study of attributes associated with place as a potential risk factor. Many of the studies reviewed are largely hypothesis generating, and a better understanding of the role of geography in the study of CKD awaits investigations that probe the mechanisms that link attributes of place to disease processes.

Greater variability in kidney function is associated with an increased risk of death

Intra-individual variability in kidney function is a common phenomenon; however, predictors of kidney function variability and its prognostic significance are not known. To examine this question, we assembled a cohort of 51,304 US veterans with an estimated glomerular filtration rate (eGFR) <60 ml/min at the end of the study period and who had at least two eGFR measurements during the previous 3 years. Variability in kidney function was defined for each patient as the coefficient of variation of the regression line fitted to all outpatient measures of eGFR during this time frame. In adjusted analyses, blacks, women, and those with Current Procedural Terminology and ICD-9-CM diagnostic codes for hypertension, diabetes, cardiovascular disease, peripheral artery disease, chronic lung disease, hepatitis C, dementia, acute kidney injury, and those with a greater number of hospitalizations had greater variability in eGFR. After a median follow-up of 4.9 years, there were 23.66%, 25.68%, and 31.23% deaths among patients in the lowest, intermediate, and highest tertiles of eGFR variability, respectively. Compared with the referent (those in the lowest tertile), patients in the highest tertile had a significantly increased risk of death with a hazard ratio of 1.34 (1.28-1.40), an association consistently present in all sensitivity analyses. Thus, our results demonstrate that greater variability in kidney function is independently associated with increased risk of death.

Validation of reported predialysis nephrology care of older patients initiating dialysis

The Centers for Medicare and Medicaid Services (CMS) Medical Evidence Report (form CMS-2728) queries providers about the timing of the patient's first nephrologist consultation before initiation of dialysis. The monitoring of disease-specific goals in the Healthy People 2020 initiative will use information from this question, but the accuracy of the reported information is unknown. We defined a cohort of 80,509 patients aged ≥67 years who initiated dialysis between July 2005 and December 2008 with ≥2 years of uninterrupted Medicare coverage as their primary payer. The primary referent, determined from claims data, was the first observed outpatient nephrologist consultation; secondary analyses used the earliest nephrology consultation, whether inpatient or outpatient. We used linear regression models to assess the associations among the magnitude of discrepant reporting and patient characteristics and we tested for any temporal trends. When using the earliest recorded outpatient nephrology encounter, agreement between the two sources of ascertainment was 48.2%, and the κ statistic was 0.29 when we categorized the timing of the visit into four periods (never, <6, 6-12, and >12 months). When we dichotomized the timing of first predialysis nephrology care at >12 or ≤12 months, accuracy was 70% (κ=0.36), but it differed by patient characteristics and declined over time. In conclusion, we found substantial disagreement between information from the CMS Medical Evidence Report and Medicare physician claims on the timing of first predialysis nephrologist care. More-specific instructions may improve reporting and increase the utility of form CMS-2728 for research and public health surveillance.

Differences in quality of life of hemodialysis patients between dialysis centers

PURPOSE

Hemodialysis patients undergo frequent and long visits to the clinic to receive adequate dialysis treatment, medical guidance, and support. This may affect health-related quality of life (HRQOL). Although HRQOL is a very important management aspect in hemodialysis patients, there is a paucity of information on the differences in HRQOL between centers. We set out to assess the differences in HRQOL of hemodialysis patients between dialysis centers and explore which modifiable center characteristics could explain possible differences.

METHODS

This cross-sectional study evaluated 570 hemodialysis patients from 24 Dutch dialysis centers. HRQOL was measured with the Kidney Disease Quality Of Life-Short Form (KDQOL-SF).

RESULTS

After adjustment for differences in case-mix, three HRQOL domains differed between dialysis centers: the physical composite score (PCS, P = 0.01), quality of social interaction (P = 0.04), and dialysis staff encouragement (P = 0.001). These center differences had a range of 11-21 points on a scale of 0-100, depending on the domain. Two center characteristics showed a clinical relevant relation with patients' HRQOL: dieticians' fulltime-equivalent and the type of dialysis center.

CONCLUSION

This study showed that clinical relevant differences exist between dialysis centers in multiple HRQOL domains. This is especially remarkable as hemodialysis is a highly standardized therapy.

Prevalence of arteriovenous fistulas in incident hemodialysis patients: correlation with patient factors that may be associated with maturation failure

BACKGROUND

Lok et al previously reported a risk equation for arteriovenous fistula (AVF) maturation failure. It is unclear whether this model or a more comprehensive model correlates with incident AVF use in the US hemodialysis population.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

195,756 adult patients initiating outpatient hemodialysis therapy in the United States between July 1, 2005, and December 31, 2009, with 6 months or more prior nephrology care.

PREDICTOR

Patient characteristics (age, peripheral vascular disease, coronary artery disease, and race) populating the AVF maturation failure risk equation and other demographic and clinical variables from the Centers for Medicare & Medicaid Services (CMS) Medical Evidence Report (CMS 2728).

OUTCOMES & MEASUREMENTS

AVF use at first outpatient dialysis treatment as recorded on the CMS 2728.

RESULTS

Using the risk categories defined by Lok et al, AVF use varied from 19.0% (very high risk) to 25.6% (low risk). In a model using only these risk categories, logistic regression showed lower ORs for moderate-, 0.90 (95% CI, 0.88-0.93); high-, 0.80 (95% CI, 0.78-0.83); and very high-risk patients, 0.68 (95% CI, 0.63-0.73) compared with low risk. In the expanded model, odds were lower for women, blacks, Hispanics, age older than 85 years, diabetes, peripheral vascular disease, congestive heart failure, other cardiac disease, and underweight. Odds were higher for hypertension, overweight, obesity, 12 months or more nephrologist care, most insurance types, and each successive year after 2005. Despite associations, the C statistic for the expanded model was 0.64.

LIMITATIONS

This analysis is limited by lack of access creation history before dialysis therapy initiation and minimal external validation of CMS 2728 data.

CONCLUSIONS

Clinical risk factors identified by Lok and expanded in this analysis have limited ability to predict incident AVF use. Even patients judged at highest risk can have successful AVF construction and initiate dialysis therapy through a functioning AVF.

Regional differences in dialysis care and mortality among American Indians and Alaska Natives

American Indians/Alaska Natives (AIANs) compose a heterogeneous population that includes geographically distinct tribal communities, many with high rates of ESRD. Regional features of dialysis care and mortality are unknown in this population. Here, we describe the structure of dialysis care and mortality of adult AIANs who initiated maintenance dialysis during 1995-2008 in different regions of the US. Overall, 13,716 AIANs received dialysis at 2054 facilities. Approximately 10% (n = 197) of these facilities provided care to two-thirds (n = 9011) of AIANs. AIANs from the Southwest and Alaska were concentrated in relatively few dialysis facilities whereas those in the Eastern US and Pacific Coast were distributed more diffusely. Despite comparably high rates of poverty, diabetes, and cardiovascular disease, annual mortality rates were lower in the Southwest (13.9%) compared with the Southern Plains (23.2%), Alaska (21.2%), Eastern US (20.0%), Northern Plains (20.8%), and Pacific Coast (22.0%). These regional differences were consistent over time and persisted after adjusting for sociodemographic and clinical variables and area-based poverty. In conclusion, regional differences in the structure of dialysis care and patient mortality exist among AIANs. Southwestern AIANs experience the highest concentration of dialysis care and the lowest mortality. Our findings suggest that an area-based approach examining the care structure of relatively few dialysis facilities may delineate determinants of these differences and improve the quality of care to many AIAN communities.

Geographic variation in cardioprotective antihypertensive medication usage in dialysis patients

BACKGROUND

Despite their high risk of adverse cardiac outcomes, persons on long-term dialysis therapy have had lower use of antihypertensive medications with cardioprotective properties, such as angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs), β-blockers, and calcium channel blockers, than might be expected. We constructed a novel database that permits detailed exploration into the demographic, clinical, and geographic factors associated with the use of these agents in hypertensive long-term dialysis patients.

STUDY DESIGN

National cross-sectional retrospective analysis linking Medicaid prescription drug claims with US Renal Data System core data.

SETTING & PARTICIPANTS

48,882 hypertensive long-term dialysis patients who were dually eligible for Medicaid and Medicare services in 2005.

FACTORS

Demographics, comorbid conditions, functional status, and state of residence.

OUTCOMES

Prevalence of cardioprotective antihypertensive agents in Medicaid pharmacy claims and state-specific observed to expected ORs of medication exposure.

MEASUREMENTS

Factors associated with medication use were modeled using multilevel logistic regression models.

RESULTS

In multivariable analyses, cardioprotective antihypertensive medication exposure was associated significantly with younger age, female sex, nonwhite race, intact functional status, and use of in-center hemodialysis. Diabetes was associated with a statistically significant 28% higher odds of ACE-inhibitor/ARB use, but congestive heart failure was associated with only a 9% increase in the odds of β-blocker use and no increase in ACE-inhibitor/ARB use. There was substantial state-by-state variation in the use of all classes of agents, with a greater than 2.9-fold difference in adjusted-rate ORs between the highest and lowest prescribing states for ACE inhibitors/ARBs and a 3.6-fold difference for β-blockers.

LIMITATIONS

Limited generalizability beyond study population.

CONCLUSIONS

In publicly insured long-term dialysis patients with hypertension, there were marked differences in use rates by state, potentially due in part to differences in Medicaid benefits. However, geographic characteristics also were associated with exposure, suggesting clinical uncertainty about the utility of these medications.

Performance measurement in chronic kidney disease

Do Americans receive high-value health care? Value only improves by advancing key indicators in one of two directions: increasing quality, decreasing cost, or both. In the face of unyielding mortality rates and the relentless expense of end-stage renal disease, government agencies and professional organizations are now focusing on new quality measures for patients with advancing chronic kidney disease. These performance measures are in early stages of refinement but reflect efforts of payers to slow the incidence of progressive renal disease across the population. To improve quality of care, one must study the performance measures themselves and determine how to capture the necessary data efficiently, identify the appropriate patients for measurement, and assign accountability to providers. Here, we discuss the challenges of doing this well.

How does late nephrological co-management impact chronic kidney disease? - an observational study

AIMS

To assess the impact of late referral (LR) for nephrological co-management compared with early referral (ER) on morbidity and mortality in chronic kidney disease (CKD) and to identify individual factors associated with higher mortality in LR, correcting for lead-time and immortal time bias.

PATIENTS AND METHODS

Retrospective observational study comparing 46 LR patients with 103 ER patients. The quality of CKD management was assessed by measures to prevent CKD progression and to modify CKD complications and cardiovascular risk factors according to current guidelines. One-year mortality of LR and ER was compared and factors associated with mortality were identified. Analysis was performed with equivalent GFR (glomerular filtration rate) of ER and LR at baseline to correct for lead-time and immortal time bias.

RESULTS

Late referral was associated with inferior control of most risk factors for CKD progression, CKD complications and cardiovascular risk factors. In particular, glycaemic control, the use of angiotensin converting enzyme inhibitors and angiotensin-2-receptor blockers in diabetic nephropathy or proteinuria, the control of nutritional and volume status were inferior in LR. One-year mortality was significantly higher in LR (RR 5.9 (95% CI 1.5-19.6); p < 0.01). Inadequate control of blood pressure, anaemia, volume status, malnutrition and emergency initial dialysis, but not LR itself were independently associated with mortality.

CONCLUSIONS

Late referral was associated with a substantially lower survival after correction for lead-time and immortal time bias and with inferior control of most risk factors for CKD progression, complications and cardiovascular risk factors. CKD patients may particularly profit from adequate control of blood pressure, anaemia, nutritional and volume status, and avoidance of emergency initial dialysis as these factors may predominately contribute to survival.

Dedication of a nurse to educating suboptimal haemodialysis starts improved transition to independent modalities of renal replacement therapy

BACKGROUND

Haemodialysis (HD) initiation is unplanned in up to 50% of patients, mainly due to late diagnosis and/or late nephrology referral. In these patients, time does not permit the multidisciplinary predialysis care that is associated with increased independent renal replacement therapy (RRT) modality choice and better access to kidney transplantation. We established a Renal Triage Nurse (RTN) position to educate suboptimal HD starts and to facilitate transition to independent modalities of RRT.

METHODS

Adult patients starting HD from 1 January 2005 to 31 December 2008 with < 180 days nephrology follow-up and surviving at least 180 days were included (suboptimal HD starts). The RTN educated suboptimal HD starts beginning in December 2006. Patients initiating RRT via the multidisciplinary predialysis clinic (MPC) were included for comparison. Multivariable logistic regression was used to determine the association between being seen by the RTN and achieving independent modalities of RRT.

RESULTS

There were 176 patients: 78 suboptimal HD starts (38 of these were educated by the RTN) and 98 patients initiated RRT after a minimum 180-day follow-up at the MPC. Of the RTN patients, 27.8% switched to independent RRT modalities (peritoneal dialysis n = 7, home haemodialysis n = 1, transplant n = 2). RTN patients were more likely to live alone (33.3% versus 10.8%, P = 0.02) and to have cerebrovascular disease (25.0% versus 7.1%, P = 0.03); however, adjusting for these variables, suboptimal HD starts seen by the RTN were more likely to transition to independent RRT (OR 3.75, 95% CI 1.08-13.05) than those not seen. The proportion starting on an independent modality via the MPC was 39.8%. The RTN achieved a rate of independent RRT not statistically different to that observed in patients starting RRT via the MPC (OR 0.74, 95% CI 0.19-2.94 in multivariable analysis).

CONCLUSIONS

Addition of the RTN to the HD care team facilitated transition to independent modalities of RRT in suboptimal HD starts. This standardized approach to the care of such patients should be considered in HD units where suboptimal HD starts are common.

Signs and symptoms associated with earlier dialysis initiation in nursing home residents

BACKGROUND

Factors driving the trend of earlier dialysis initiation for persons with end-stage renal disease are unknown. We wanted to determine the association of the number and type of signs and symptoms with timing of initiation of dialysis in US nursing home residents.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

We used data from the US Renal Data System linked with the Minimum Data Set, a national registry of nursing home residents. The cohort consisted of 2,402 nursing home residents who initiated dialysis between 1998 and 2000 and had at least 2 recorded clinical assessments in the year before dialysis initiation.

PREDICTORS

We evaluated 7 clinical signs and symptoms: dependence in activities of daily living, cognitive function, edema, dyspnea, nutritional problems, vomiting, and body size.

OUTCOMES

Earlier dialysis initiation was defined as estimated glomerular filtration rate ≥ 1 5 mL/min/1.73 m² at the start of dialysis.

RESULTS

Median estimated glomerular filtration rate at the start of dialysis was 9.8 (25th-75th percentile, 7.4-13.4) mL/min/1.73 m². After adjustment for age, sex, race, and comorbid conditions, each additional sign or symptom was associated with a higher odds for earlier dialysis initiation (OR, 1.16 per symptom; 95% CI, 1.06-1.28), as was each adversely changing sign or symptom (OR, 1.26 per symptom; 95% CI, 1.16-1.38). The population-attributable risk for earlier dialysis initiation associated with having one or more signs and symptoms of volume overload, cognitive decline, increasing activities of daily living dependence, and weight loss was 31%; volume overload had the largest aggregate population-attributable risk.

LIMITATIONS

We lacked information about metabolic indications for dialysis initiation.

CONCLUSIONS

Volume overload, cognitive decline, increasing activities of daily living dependence, and weight loss were associated with earlier dialysis initiation; however, these factors explained less than one-third of cases of earlier dialysis initiation in nursing home residents.