Conservative kidney management and kidney supportive care: core components of integrated care for people with kidney failure

Integrated kidney care requires synergistic linkage between preventative care for people at risk for chronic kidney disease and health services providing care for people with kidney disease, ensuring holistic and coordinated care as people transition between acute and chronic kidney disease and the 3 modalities of kidney failure management: conservative kidney management, transplantation, and dialysis. People with kidney failure have many supportive care needs throughout their illness, regardless of treatment modality. Kidney supportive care is therefore a vital part of this integrated framework, but is nonexistent, poorly developed, and/or poorly integrated with kidney care in many settings, especially in low- and middle-income countries. To address this, the International Society of Nephrology has (i) coordinated the development of consensus definitions of conservative kidney management and kidney supportive care to promote international understanding and awareness of these active treatments; and (ii) identified key considerations for the development and expansion of conservative kidney management and kidney supportive care programs, especially in low resource settings, where access to kidney replacement therapy is restricted or not available. This article presents the definitions for conservative kidney management and kidney supportive care; describes their core components with some illustrative examples to highlight key points; and describes some of the additional considerations for delivering conservative kidney management and kidney supportive care in low resource settings.

The ASCEND-NHQ trial found positive effects of daprodustat on hemoglobin and quality of life in patients with non-dialysis-dependent chronic kidney disease

The ASCEND-NHQ trial evaluated the effects of daprodustat on hemoglobin and the Medical Outcomes Study 36-item Short Form Survey (SF-36) Vitality score (fatigue) in a multicenter, randomized, double-blind, placebo-controlled trial. Adults with chronic kidney disease (CKD) Stages 3-5, hemoglobin 8.5-10.0 g/dl, transferrin saturation 15% or more, and ferritin 50 ng/ml or more without recent erythropoiesis-stimulating agent use were randomized (1:1) to oral daprodustat or placebo to achieve and maintain target hemoglobin of 11-12 g/dl over 28 weeks. The primary endpoint was the mean change in hemoglobin between baseline and the evaluation period (Weeks 24-28). Principal secondary endpoints were proportion of participants with a 1 g/dl or more increase in hemoglobin and mean change in the vitality score between baseline and Week 28. Outcome superiority was tested (one-sided alpha level of 0.025) among 614 randomized participants. The adjusted mean change in hemoglobin from baseline to the evaluation period was greater with daprodustat (1.58 vs 0.19 g/dl). The adjusted mean treatment difference (AMD) was significant at 1.40 g/dl (95% confidence interval 1.23, 1.56). A greater proportion of participants receiving daprodustat showed a significant 1 g/dl or more increase in hemoglobin from baseline (77% vs 18%). The mean SF-36 Vitality score increased by 7.3 and 1.9 points with daprodustat and placebo, respectively; a significant 5.4 point Week 28 ADM increase. Adverse event rates were similar (69% vs 71%); relative risk 0.98, (95% confidence interval 0.88, 1.09). Thus, in participants with CKD Stages 3-5, daprodustat resulted in a significant increase in hemoglobin and improvement in fatigue without an increase in the overall frequency of adverse events.

Regional Variation of Erythropoiesis-Stimulating Agent Hyporesponsiveness in the Global Daprodustat Dialysis Study (ASCEND-D)

INTRODUCTION

Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) affects 10-15% of the chronic dialysis population. We explored baseline characteristics and predictors of ESA hyporesponsiveness in a global randomized cardiovascular outcomes study comparing an investigational hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), daprodustat, with conventional ESA treatment.

METHODS

ASCEND-D (NCT02879305) recruited 2964 chronic dialysis patients receiving ESA treatment (standardized to weekly intravenous [IV] epoetin) who were iron replete at baseline. The primary ESA hyporesponsiveness definition was an ESA Resistance Index (ERI, ESA Units/kg/week/hemoglobin g/l) ≥2 or IV standardized ESA dose ≥450 Units/kg/week. Predictors of ESA hyporesponsiveness were determined using a multivariable regression model. Alternative hyporesponder definitions were explored.

RESULTS

Using the primary definition, 354 (12%) patients were ESA hyporesponsive. Geographic region, notably Latin America, lower baseline body mass index and transferrin saturation, younger age, lower albumin concentration, and a higher baseline IV iron dose were identified as strongly associated (P < 0.001) with ESA hyporesponsiveness. Additional predictors of ESA hyporesponsiveness included female sex (P = 0.010), history of heart failure (P = 0.035), longer dialysis vintage (P = 0.077), smoking status (P = 0.247), aspirin use (P = 0.121), and angiotensin-converting enzyme inhibitor/ angiotensin receptor blocker use (P = 0.214).

CONCLUSION

This is the first global HIF-PHI study to report pre-specified definitions and predictors of ESA hyporesponsiveness. While most of the predictors identified in our study have been previously reported, geographic region stands out as an unexpected finding, meriting further investigation.

Factors Associated With the Quality of the Patient-Doctor Relationship: A Cross-Sectional Study of Ambulatory Mexican Patients With Rheumatic Diseases

BACKGROUND

The patient-doctor relationship (PDR) is a complex phenomenon with strong cultural determinants, which impacts health-related outcomes and, accordingly, does have ethical implications. The study objective was to describe the PDR from medical encounters between 600 Mexican outpatients with rheumatic diseases and their attending rheumatologists, and to identify factors associated with a good PDR.

METHODS

A cross-sectional study was performed. Patients completed the PDRQ-9 (Patient-Doctor Relationship Questionnaire, 9 items), the HAQ-DI (Health Assessment Questionnaire Disability Index), the Short-Form 36 items (SF-36), a pain-visual analog scale, and the Ideal Patient Autonomy Scale. Relevant sociodemographic, disease-related, and treatment-related variables were obtained. Patients assigned a PDRQ-9 score to each patient-doctor encounter. Regression analysis was used to identify factors associated with a good PDR, which was defined based on a cutoff point established using the borderline performance method.

RESULTS

Patients were primarily middle-aged female subjects (86%), with substantial disease duration (median, 11.1 years), without disability (HAQ-DI within reference range, 55.3%), and with deteriorated quality of life (SF-36 out of reference range, 73.7%-78.6%). Among them, 36.5% had systemic lupus erythematosus and 31.8% had rheumatoid arthritis. There were 422 patients (70.3%) with a good PDR and 523 medical encounters (87.2%) involved certified rheumatologists.Patient paternalistic ideal of autonomy (odds ratio [OR], 3.029; 95% confidence interval [CI], 1.793-5.113), SF-36 score (OR, 1.014; 95% CI, 1.003-1.025), female sex (OR, 0.460; 95% CI, 0.233-0.010), and being certified rheumatologist (OR, 1.526; 95% CI, 1.059-2.200) were associated with a good PDR.

CONCLUSIONS

Patient-related factors and the degree of experience of the attending physician impact the quality of the PDR, in Mexican outpatients with rheumatic diseases.

Efficacy and Safety of Daprodustat for Treatment of Anemia of Chronic Kidney Disease in Incident Dialysis Patients: A Randomized Clinical Trial

IMPORTANCE

Daprodustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, is being evaluated as an oral alternative to conventional erythropoiesis-stimulating agent (ESA) therapy. Few studies of anemia treatment in an incident dialysis (ID) population have been reported.

OBJECTIVE

To evaluate the efficacy and safety of daprodustat vs darbepoetin alfa in treating anemia of chronic kidney disease in ID patients.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, randomized, open-label clinical trial was conducted from May 11, 2017, through September 24, 2020, in 90 centers across 14 countries. Patients with advanced CKD were eligible if they planned to start dialysis within 6 weeks from screening or had started and received hemodialysis (HD) or peritoneal dialysis (PD) within 90 days before randomization, had a screening hemoglobin (Hb) concentration of 8.0 to 10.5 g/dL (to convert to grams per liter, multiply by 10) and a randomization Hb of 8.0 to 11.0 g/dL, were ESA-naive or had received limited ESA treatment, and were iron-replete.

INTERVENTIONS

Randomized 1:1 to daprodustat or darbepoetin alfa.

MAIN OUTCOMES AND MEASURES

The primary analysis in the intent-to-treat population evaluated the mean change in Hb concentration from baseline to evaluation period (weeks 28-52) to assess noninferiority of daprodustat vs darbepoetin alfa (noninferiority margin, -0.75 g/dL). The mean monthly intravenous (IV) iron dose from baseline to week 52 was the principal secondary end point. Rates of treatment-emergent and serious adverse events (AEs) were also compared between treatment groups to assess safety and tolerability.

RESULTS

A total of 312 patients (median [IQR] age, 55 [45-65] years; 194 [62%] male) were randomized to either daprodustat (157 patients; median [IQR] age, 52.0 [45-63] years; 96 [61%] male) or darbepoetin alfa (155 patients; median [IQR] age, 56.0 [45-67] years; 98 [63%] male); 306 patients (98%) completed the trial. The mean (SD) Hb concentration during the evaluation period was 10.5 (1.0) g/dL for the daprodustat and 10.6 (0.9) g/dL for the darbepoetin alfa group, with an adjusted mean treatment difference of -0.10 g/dL (95% CI, -0.34 to 0.14 g/dL), indicating noninferiority. There was a reduction in mean monthly IV iron use from baseline to week 52 in both treatment groups; however, daprodustat was not superior compared with darbepoetin alfa in reducing monthly IV iron use (adjusted mean treatment difference, 19.4 mg [95% CI, -11.0 to 49.9 mg]). Adverse event rates were 76% for daprodustat vs 72% for darbepoetin alfa.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that daprodustat was noninferior to darbepoetin alfa in treating anemia of CKD and may represent a potential oral alternative to a conventional ESA in the ID population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03029208.

Daprodustat for the Treatment of Anemia in Patients Not Undergoing Dialysis

BACKGROUND

Daprodustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor. In patients with chronic kidney disease (CKD) who are not undergoing dialysis, the efficacy and safety of daprodustat, as compared with the conventional erythropoiesis-stimulating agent darbepoetin alfa, are unknown.

METHODS

In this randomized, open-label, phase 3 trial with blinded adjudication of cardiovascular outcomes, we compared daprodustat with darbepoetin alfa for the treatment of anemia in patients with CKD who were not undergoing dialysis. The primary outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52 and the first occurrence of a major adverse cardiovascular event (MACE; a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke).

RESULTS

Overall, 3872 patients were randomly assigned to receive daprodustat or darbepoetin alfa. The mean (±SD) baseline hemoglobin levels were similar in the two groups. The mean (±SE) change in the hemoglobin level from baseline to weeks 28 through 52 was 0.74±0.02 g per deciliter in the daprodustat group and 0.66±0.02 g per deciliter in the darbepoetin alfa group (difference, 0.08 g per deciliter; 95% confidence interval [CI], 0.03 to 0.13), which met the prespecified noninferiority margin of -0.75 g per deciliter. During a median follow-up of 1.9 years, a first MACE occurred in 378 of 1937 patients (19.5%) in the daprodustat group and in 371 of 1935 patients (19.2%) in the darbepoetin alfa group (hazard ratio, 1.03; 95% CI, 0.89 to 1.19), which met the prespecified noninferiority margin of 1.25. The percentages of patients with adverse events were similar in the two groups.

CONCLUSIONS

Among patients with CKD and anemia who were not undergoing dialysis, daprodustat was noninferior to darbepoetin alfa with respect to the change in the hemoglobin level from baseline and with respect to cardiovascular outcomes. (Funded by GlaxoSmithKline; ASCEND-ND ClinicalTrials.gov number, NCT02876835.).

Daprodustat for the Treatment of Anemia in Patients Undergoing Dialysis

BACKGROUND

Among patients with chronic kidney disease (CKD), the use of recombinant human erythropoietin and its derivatives for the treatment of anemia has been linked to a possibly increased risk of stroke, myocardial infarction, and other adverse events. Several trials have suggested that hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors (PHIs) are as effective as erythropoiesis-stimulating agents (ESAs) in increasing hemoglobin levels.

METHODS

In this randomized, open-label, phase 3 trial, we assigned patients with CKD who were undergoing dialysis and who had a hemoglobin level of 8.0 to 11.5 g per deciliter to receive an oral HIF-PHI (daprodustat) or an injectable ESA (epoetin alfa if they were receiving hemodialysis or darbepoetin alfa if they were receiving peritoneal dialysis). The two primary outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52 (noninferiority margin, -0.75 g per deciliter) and the first occurrence of a major adverse cardiovascular event (a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke), with a noninferiority margin of 1.25.

RESULTS

A total of 2964 patients underwent randomization. The mean (±SD) baseline hemoglobin level was 10.4±1.0 g per deciliter overall. The mean (±SE) change in the hemoglobin level from baseline to weeks 28 through 52 was 0.28±0.02 g per deciliter in the daprodustat group and 0.10±0.02 g per deciliter in the ESA group (difference, 0.18 g per deciliter; 95% confidence interval [CI], 0.12 to 0.24), which met the prespecified noninferiority margin of -0.75 g per deciliter. During a median follow-up of 2.5 years, a major adverse cardiovascular event occurred in 374 of 1487 patients (25.2%) in the daprodustat group and in 394 of 1477 (26.7%) in the ESA group (hazard ratio, 0.93; 95% CI, 0.81 to 1.07), which also met the prespecified noninferiority margin for daprodustat. The percentages of patients with other adverse events were similar in the two groups.

CONCLUSIONS

Among patients with CKD undergoing dialysis, daprodustat was noninferior to ESAs regarding the change in the hemoglobin level from baseline and cardiovascular outcomes. (Funded by GlaxoSmithKline; ASCEND-D ClinicalTrials.gov number, NCT02879305.).

The ASCEND-ND trial: Study design and participant characteristics

Background

Anaemia is common in chronic kidney disease (CKD) and assessment of the risks and benefits of new therapies is important.

Methods

The Anaemia Study in CKD: Erythropoiesis via a Novel prolyl hydroxylase inhibitor Daprodustat-Non-Dialysis (ASCEND-ND) trial includes adult patients with CKD Stages 3–5, not using erythropoiesis-stimulating agents (ESAs) with screening haemoglobin (Hb) 8–10 g/dL or receiving ESAs with screening Hb of 8–12 g/dL. Participants were randomized to daprodustat or darbepoetin alfa (1:1) in an open-label trial (steering committee- and sponsor-blinded), with blinded endpoint assessment. The co-primary endpoints are mean change in Hb between baseline and evaluation period (average over Weeks 28–52) and time to first adjudicated major adverse cardiovascular (CV) event. Baseline characteristics were compared with those of participants in similar anaemia trials.

Results

Overall, 3872 patients were randomized from 39 countries (median age 67 years, 56% female, 56% White, 27% Asian and 10% Black). The median baseline Hb was 9.9 g/dL, blood pressure was 135/74 mmHg and estimated glomerular filtration rate was 18 mL/min/1.73 m². Among randomized patients, 53% were ESA non-users, 57% had diabetes and 37% had a history of CV disease. At baseline, 61% of participants were using renin–angiotensin system blockers, 55% were taking statins and 49% were taking oral iron. Baseline demographics were similar to those in other large non-dialysis anaemia trials.

Conclusion

ASCEND-ND will define the efficacy and safety of daprodustat compared with darbepoetin alfa in the treatment of patients with anaemia associated with CKD not on dialysis.

Decreased kidney function and agricultural work: a cross-sectional study in middle-aged adults from Tierra Blanca, Mexico

BACKGROUND

We aimed to determine the prevalence of decreased kidney function in a potential chronic kidney disease (KD) of unknown aetiology hotspot in Mexico, assess its distribution across occupations and examine the associated risk factors.

METHODS

A cross-sectional study collected sociodemographic, occupational, medical and biometric data from 616 men and women aged 20-60 years who were residents of three communities within the Tierra Blanca region in Mexico. Kidney function was assessed by standardized serum creatinine and estimated glomerular filtration rate (eGFR) and semi-quantitative albumin-to-creatinine ratio (ACR). To examine the distribution of decreased kidney function within the population, age- and sex-adjusted prevalence of low eGFR (≤60 mL/min/1.73 m2) was estimated for all participants and across occupations. Multivariable logistic regression was used to assess the association of occupation with having low eGFR.

RESULTS

Of the 579 participants analysed (37 excluded due to missing data), the age- and sex-adjusted prevalence of low eGFR was 3.5%. Agriculture was the occupation associated with the highest adjusted prevalence of low eGFR (8.8%), with 1 in every 11 agricultural workers having low eGFR. Working in agriculture was independently associated with more than a 5-fold risk of having low eGFR [odds ratio 5.2 (95% confidence interval 1.1-24.3), P = 0.032], after adjustment for age, sex, diabetes, hypertension, body mass index, ACR and family history of KD. Additionally, a quarter of the population (25%) had either low eGFR or an ACR >30 mg/g, mostly due to albuminuria.

CONCLUSIONS

Our work suggests that there is a high prevalence of decreased kidney function in Tierra Blanca, particularly amongst agricultural workers.

Study design and baseline characteristics of patients on dialysis in the ASCEND-D trial

Background

The Anemia Studies in chronic kidney disease (CKD): Erythropoiesis via a Novel prolyl hydroxylase inhibitor Daprodustat-Dialysis (ASCEND-D) trial will test the hypothesis that daprodustat is noninferior to comparator epoetin alfa or darbepoetin alfa for two co-primary endpoints: hemoglobin (Hb) efficacy and cardiovascular (CV) safety.

Methods

We report the trial design, key demographic, clinical and laboratory findings, and baseline therapies of 2964 patients randomized in the open-label (sponsor-blinded) active-controlled, parallel-group, randomized ASCEND-D clinical trial. We also compare baseline characteristics of ASCEND-D patients with patients who are on dialysis (CKD G5D) enrolled in other large CV outcome trials (CVOTs) and in the most relevant registries.

Results

The median age of patients was 58 years, 43% were female; 67% were White and 16% were Black. The median Hb at baseline was 10.4 g/dL. Among randomized patients, 89% were receiving hemodialysis and 11% peritoneal dialysis. Among key comorbidities, 42% reported a history of diabetes mellitus and 45% a history of CV disease. Median blood pressure was 134/74 mmHg. The median weekly dose of epoetin was 5751 units. Intravenous and oral iron uses were noted in 64 and 11% of patients, respectively. Baseline demographics were similar to patients with CKD G5D enrolled in other CVOTs and renal patient registries.

Conclusions

ASCEND-D will evaluate the efficacy and safety of daprodustat compared with epoetin alfa or darbepoetin alfa in the treatment of patients with anemia with CKD G5D.

This trial is registered with ClinicalTrials.gov: NCT02879305. EudraCT Number: 2016-000541-31; Sponsor Protocol Number: 200807.

Validation of a Core Patient-Reported Outcome Measure for Fatigue in Patients Receiving Hemodialysis: The SONG-HD Fatigue Instrument

BACKGROUND AND OBJECTIVES

Fatigue is a very common and debilitating symptom and identified by patients as a critically important core outcome to be included in all trials involving patients receiving hemodialysis. A valid, standardized measure for fatigue is needed to yield meaningful and relevant evidence about this outcome. This study validated a core patient-reported outcome measure for fatigue in hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A longitudinal cohort study was conducted to assess the validity and reliability of a new fatigue measure (Standardized Outcomes in Nephrology-Hemodialysis Fatigue [SONG-HD Fatigue]). Eligible and consenting patients completed the measure at three time points: baseline, a week later, and 12 days following the second time point. Cronbach α and intraclass correlation coefficient were calculated to assess internal consistency, and Spearman rho was used to assess convergent validity. Confirmatory factor analysis was also conducted. Hemodialysis units in the United Kingdom, Australia, and Romania participated in this study. Adult patients aged 18 years and over who were English speaking and receiving maintenance hemodialysis were eligible to participate. Standardized Outcomes in Nephrology-Hemodialysis, the Visual Analog Scale for fatigue, the 12-Item Short Form Survey, and Functional Assessment of Chronic Illness Therapy-Fatigue were used.

RESULTS

In total, 485 participants completed the study across the United Kingdom, Australia, and Romania. Psychometric assessment demonstrated that Standardized Outcomes in Nephrology-Hemodialysis is internally consistent (Cronbach α =0.81-0.86) and stable over a 1-week period (intraclass correlation coefficient =0.68-0.74). The measure demonstrated convergence with Functional Assessment of Chronic Illness Therapy-Fatigue and had moderate correlations with other measures that assessed related but not the same concept (the 12-Item Short Form Survey and the Visual Analog Scale). Confirmatory factor analysis supported the one-factor model.

CONCLUSIONS

SONG-HD Fatigue seems to be a reliable and valid measure to be used in trials involving patients receiving hemodialysis.

Supportive care for end-stage kidney disease: an integral part of kidney services across a range of income settings around the world

A key component of treatment for all people with advanced kidney disease is supportive care, which aims to improve quality of life and can be provided alongside therapies intended to prolong life, such as dialysis. This article addresses the key considerations of supportive care as part of integrated end-stage kidney disease care, with particular attention paid to programs in low- and middle-income countries. Supportive care should be an integrated component of care for patients with advanced chronic kidney disease, patients receiving kidney replacement therapy (KRT), and patients receiving non-KRT conservative care. Five themes are identified: improving information on prognosis and support, developing context-specific evidence, establishing appropriate metrics for monitoring care, clearly communicating the role of supportive care, and integrating supportive care into existing health care infrastructures. This report explores some general aspects of these 5 domains, before exploring their consequences in 4 health care situations/settings: in people approaching end-stage kidney disease in high-income countries and in low- and middle-income countries, and in people discontinuing KRT in high-income countries and in low- and middle-income countries.

Challenges for sustainable end-stage kidney disease care in low-middle-income countries: the problem of the workforce

Prevention and early detection of kidney diseases in adults and children should be a priority for any government health department. This is particularly pertinent in the low-middle-income countries, mostly in Asia, Africa, Latin America, and the Caribbean, where up to 7 million people die because of lack of end-stage kidney disease treatment. The nephrology workforce (nurses, technicians, and doctors) is limited in these countries and expanding the size and expertise of the workforce is essential to permit expansion of treatment for both chronic kidney disease and end-stage kidney disease. To achieve this will require sustained action and commitment from governments, academic medical centers, local nephrology societies, and the international nephrology community.

Genetic and environmental risk factors for chronic kidney disease

In order to change the current state of chronic kidney disease knowledge and therapeutics, a fundamental improvement in the understanding of genetic and environmental causes of chronic kidney disease is essential. This article first provides an overview of the existing knowledge gaps in our understanding of the genetic and environmental causes of chronic kidney disease, as well as their interactions. The second part of the article formulates goals that should be achieved in order to close these gaps, along with suggested timelines and stakeholders that are to be involved. A better understanding of genetic and environmental factors and their interactions that influence kidney function in healthy and diseased conditions can provide novel insights into renal physiology and pathophysiology and result in the identification of novel therapeutic or preventive targets to tackle the global public health care problem of chronic kidney disease.

Strategies to improve monitoring disease progression, assessing cardiovascular risk, and defining prognostic biomarkers in chronic kidney disease

Chronic kidney disease (CKD) is a major global public health problem with significant gaps in research, care, and policy. In order to mitigate the risks and adverse effects of CKD, the International Society of Nephrology has created a cohesive set of activities to improve the global outcomes of people living with CKD. Improving monitoring of renal disease progression can be done by screening and monitoring albuminuria and estimated glomerular filtration rate in primary care. Consensus on how many times and how often albuminuria and estimated glomerular filtration rate are measured should be defined. Meaningful changes in both renal biomarkers should be determined in order to ascertain what is clinically relevant. Increasing social awareness of CKD and partnering with the technological community may be ways to engage patients. Furthermore, improving the prediction of cardiovascular events in patients with CKD can be achieved by including the renal risk markers albuminuria and estimated glomerular filtration rate in cardiovascular risk algorithms and by encouraging uptake of assessing cardiovascular risk by general practitioners and nephrologists. Finally, examining ways to further validate and implement novel biomarkers for CKD will help mitigate the global problem of CKD. The more frequent use of renal biopsy will facilitate further knowledge into the underlying etiologies of CKD and help put new biomarkers into biological context. Real-world assessments of these biomarkers in existing cohorts is important, as well as obtaining regulatory approval to use these biomarkers in clinical practice. Collaborations among academia, physician and patient groups, industry, payer organizations, and regulatory authorities will help improve the global outcomes of people living with CKD.

Effect of red cell transfusions on future kidney transplantation

Red cell transfusions, erythropoiesis-stimulating agents (ESAs), and intravenous iron therapy all have a place in the treatment of anemia associated with CKD. Their relative merits and uses are subject to many clinical and nonclinical factors. New concerns associated with the use of ESA therapy make it likely that the use of blood transfusions will increase, refueling previous debates about their associated risks. Data on whether red cell transfusions increase sensitization to HLA antigens, rendering subsequent transplantation more problematic, are mainly derived from older literature. Older data suggested that women were more at risk of HLA sensitization than men, particularly those with previous multiple pregnancies, although recent U.S. Renal Data System data have challenged this. HLA sensitization prolongs the waiting time for transplantation and reduces graft survival. Leukocyte depletion of red cells does not appear to reduce the risk of HLA sensitization. This review summarizes much of the data on these issues, as well as highlighting the need for further research on the potential risks for blood transfusion in patients with CKD.

Anemia of chronic kidney disease and end-stage renal disease: are there unique issues in disadvantaged populations?

Several sources of data indicate that there are racial and ethnic disparities in the management of anemia of chronic kidney disease and end-stage renal disease. In this article, I present evidence documenting these disparities and discuss possible factors that may explain the suboptimal anemia management. I also provide recommendations to improve anemia management in disadvantaged populations.

Effect of comorbidity on the increased mortality associated with early initiation of dialysis

BACKGROUND

Current recommendations for initiating dialysis therapy are based on level of kidney function and clinical evidence of uremia. Several studies reported no benefit in patient survival from initiating dialysis therapy with a greater glomerular filtration rate (GFR). Whether this is explained by a greater comorbidity burden or detrimental effect of early initiation remains unclear. We thus undertook an evaluation of the impact of comorbidity on the association between GFR at initiation and death.

METHODS

Data from the Center for Medicare & Medicaid Services were used to derive 3 incident dialysis populations: (1) general population aged 18+ years, (2) older patients aged 67+ years, and (3) a "low-risk" subgroup without diabetes, heart failure, or atherosclerotic heart disease. A Cox proportional hazard regression technique was used.

RESULTS

Greater GFR at initiation of dialysis therapy was associated with a greater risk for death in all populations, and sequential adjustment for additional covariates attenuated the effect. Patients in the general dialysis population who initiated dialysis therapy at a GFR greater than 10 mL/min/1.73 m2 (>0.17 mL/s) had a 42% increased risk for death compared with patients with a GFR less than 5 mL/min/1.73 m2 (<0.08 mL/s) at initiation of dialysis therapy after adjusting for all covariates. In the older and healthier populations, adjusted increased risks were 25% and 39%, respectively.

CONCLUSION

Patients initiating dialysis therapy at greater GFRs have an increased risk for death not fully explained by comorbidity. Additional research is required to determine the reasons for poor survival in patients who start dialysis therapy with significant residual renal function.

Trends in Intravenous Iron Use Among Dialysis Patients in the United States (1994-2002)

BACKGROUND

Two new intravenous (IV) iron products, ferric gluconate and iron sucrose, recently were approved for use in the United States. We report trends in IV iron use in both incident (1994 to 2001) and prevalent (1994 to 2002) Medicare US dialysis patients.

METHODS

Included patients had Medicare as a primary payer. Recombinant human erythropoietin doses, IV iron use, and hemoglobin data were obtained from Medicare outpatient files. The most recent cohorts included 241,770 prevalent hemodialysis (HD) patients in 2002 and 11,744 incident HD patients in 2001.

RESULTS

For incident HD patients in the first 9 months of dialysis therapy, the percentage of patients administered IV iron increased sharply between 1994 and 1997 and then increased gradually between 1997 and 2001. In 2002, a total of 84.4% of HD and 19.3% of peritoneal dialysis (PD) patients were administered IV iron. Ferric gluconate use increased slowly in 2000, increased from 5.7% to 18.6% from December 2000 to January 2001, increased to 29.8% in April 2002, and was 23.3% in December 2002. Iron sucrose use increased to 26% by December 2002. The absolute monthly percentage of HD patients administered IV iron dextran decreased from 49.6% in January 2000 to 3.6% in December 2002.

CONCLUSION

In US patients with end-stage renal disease, IV iron use has increased, although slowly, from 1997 to 2002. Ferric gluconate and iron sucrose have become the predominant form of therapy. IV iron therapy was used in a much smaller percentage of PD compared with HD patients, and racial and geographic variability was observed.

Does predialysis nephrology care influence patient survival after initiation of dialysis?

BACKGROUND

Early nephrology referral of patients with chronic kidney disease (CKD) has been suggested to reduce mortality after initiation of dialysis. This retrospective cohort study of incident dialysis patients between 1995 and 1998 was performed to address the association between frequency of nephrology care during the 24 months before initiation of dialysis and first-year mortality after initiation of dialysis.

METHODS

Patient data were obtained from the Centers for Medicare & Medicaid Services. Patients who started dialysis between 1995 and 1998, and were Medicare-eligible for at least 24 months before initiation of dialysis, were included. One or more nephrology visits during a month was considered a month of nephrology care (MNC).

RESULTS

Of the total 109,321 patients, only 50% had received nephrology care during the 24 months before initiation of dialysis. Overall, first-year mortality after initiation of dialysis was 36%. Cardiac disease was the major cause of mortality (46%). After adjusting for comorbidity, higher mortality was associated with increasing age (HR, 1.04 per year increase; 95% CI, 1.03 to 1.04) and more frequent visits to generalists (HR, 1.009 per visit increase; 95% CI, 1.003 to 1.014) and specialists (HR, 1.012 per visit increase; 95% CI, 1.011 to 1.013). Compared to patients with >/=3 MNC in the six months before initiation of dialysis, higher mortality was observed among those with no MNC during the 24 months before initiation of dialysis (HR, 1.51; 95% CI, 1.45 to 1.58), no MNC during the six months before initiation of dialysis (HR, 1.28; 95% CI, 1.20 to 1.36), and one or two MNC during the six months before initiation of dialysis (HR, 1.23; 95% CI, 1.18 to 1.29).

CONCLUSION

Nephrology care before dialysis is important, and consistency of care in the immediate six months before dialysis is a predictor of mortality. Consistent nephrology care may be more important than previously thought, particularly because the frequency and severity of CKD complications increase as patients approach dialysis.

Carnitine therapy is associated with decreased hospital utilization among hemodialysis patients

BACKGROUND/AIMS

Hospitalizations account for 41% of the total cost of end-stage renal disease (ESRD) care. Carnitine deficiency is common among dialysis patients, and some studies have shown improvements in anemia, and cardiac and skeletal muscle function upon administration of L-carnitine. We hypothesized that L-carnitine may be associated with decreased hospital utilization in these patients.

METHODS

The Fresenius Medical Care North America dialysis database was used for this retrospective analysis. Adult patients who received carnitine for at least 3 months, and had at least 3 months of pre-carnitine follow-up were included in the study. Hospitalization and hospital day rates were compared before and during carnitine therapy, and with a matched population.

RESULTS

Carnitine therapy at a mean dose of 1.5 +/- 0.7 g per administration for an average of 9.7 +/- 5.4 months was associated with a significant reduction in hospital utilization. Patients with cardiovascular disease, defined as hospitalizations for angina, myocardial infarction, arrhythmia, congestive heart failure, cerebral vascular disease or peripheral vascular disease prior to receiving carnitine, and those with anemia and hypoalbuminemia derived the greatest benefit from carnitine therapy. In a multivariate analysis, compared to 3 months prior to the initiation of carnitine, the adjusted relative risk for hospitalization was 11, 11, and 15% lower at 3, 6, and 9 months, respectively. Among patients with cardiovascular disease, the reduction in risk was even more significant (24, 31, and 34% lower at 3, 6, and 9 months, respectively). Similar results were observed with adjusted relative risk for hospital days.

CONCLUSION

Administration of L-carnitine to chronic hemodialysis patients is associated with lower hospital utilization.

Late nephrology referral and mortality among patients with end-stage renal disease: a propensity score analysis

BACKGROUND

Late nephrology referral has been associated with adverse outcomes among patients with end-stage renal disease; however, its relationship to mortality is unclear. We examined the impact of timing of nephrology care relative to initiation of dialysis on mortality after initiation of dialysis.

METHODS

Data from the Dialysis Morbidity and Mortality Study - Wave II, a prospective study of incident dialysis patients, were used. Late referral (LR) was defined as first nephrology visit <4 months and early referral (ER) as first nephrology visit >or=4 months prior to initiation of dialysis. Propensity scores (PS) were estimated using logistic regression to predict the probability that a given patient was LR. A Cox proportional hazards model was built to examine the association between timing of nephrology referral and mortality.

RESULTS

The cohort was comprised of 2195 patients: 54% were males, 66% were Caucasians, 26% were African-Americans and 33% were referred late. A Cox proportional hazards analysis demonstrated that compared with ER patients, LR patients had a 44% higher risk of death at 1 year after initiation of dialysis [hazards ratio (HR) = 1.44; 95% confidence interval (CI): 1.15-1.80], which remained significant after adjusting for quintiles of PS (HR = 1.42; 95% CI: 1.12-1.80).

CONCLUSIONS

Among patients with chronic kidney disease (CKD) who initiated dialysis, LR was associated with higher risk of death at 1 year after initiation of dialysis compared with ER.

Relationship among catheter insertions, vascular access infections, and anemia management in hemodialysis patients

BACKGROUND

Arteriovenous fistulas are the recommended permanent vascular access (VA) for chronic hemodialysis. However, in the United States most patients begin chronic hemodialysis with a catheter. Recent data suggest that VA type contributes to recombinant human erythropoietin (rHuEPO) resistance. We examined catheter insertions, VA infections, and anemia management in Medicare, rHuEPO-treated, chronic hemodialysis patients.

METHODS

We compared hemoglobin values and rHuEPO and intravenous iron dosing with concurrent catheter insertions and VA infections in 186,348 period-prevalent patients in 2000. We studied anemia management after catheter insertions and VA infections in 67,410 incident patients from 1997 to 1999. Multiple linear regression models examined follow-up hemoglobin and rHuEPO dose per week (rHuEPO/wk) by numbers of catheter insertions and hospitalizations for VA infection.

RESULTS

In the prevalent cohort, increasing temporary and permanent catheter insertions and VA infections were associated with slightly lower hemoglobin, higher rHuEPO doses, and higher intravenous iron doses. In the incident cohort, compared to patients with no VA infections or no catheter insertions (temporary or permanent), respectively, patients with 2+ VA infections or 2+ catheter insertions had 0.12 g/dL and 0.06 g/dL lower mean hemoglobin (P = 0.0028 and P < 0.0001), and 25.7% and 12.2% higher mean rHuEPO/wk (P < 0.0001).

CONCLUSION

Higher rHuEPO doses may be required to maintain similar or slightly lower mean hemoglobin values among chronic hemodialysis patients with higher numbers of catheter insertions and VA infections, compared to patients without any.

Fabry kidney disease

Fabry disease (FD), the second most common type of lysosomal storage disease (LSD), is one of 41 disorders characterized by accumulation of substances normally degraded within lysosomes. It is an X-linked recessive disorder characterized by a deficiency of lysosomal alpha-galactosidase A (alpha-Gal A). The locus for human alpha-Gal A is located on the Xq22 chromosome. Most FD mutations are confined to a single family. Although FD is an X-linked disorder, up to one third of female carriers develop clinical manifestations of the disease. It typically presents during infancy or adolescence with crisis of neuropathic pain (acroparesthesia), angiokeratomas, and asymptomatic corneal lesions. As Gb3 deposition progresses, clinical manifestations occur in other organs. Patients typically die in the fourth or fifth decade of life due to cardiac, renal or cerebrovascular complications. Usually, there is diffuse deposition of glycosphingolipid in the renal glomeruli, tubules, interstitium, and vasculature. Clinically, the renal disease manifests with hypertension, microscopic hematuria (rare), moderate proteinuria, which can be in the nephrotic range, and lipiduria. End-stage renal disease can be treated with either dialysis or transplantation. Thegene for (x-Gal A was cloned and sequenced, which eventually led to production of enzyme for therapeutic use by either recombinant DNA technology or gene activation.

Anaemia of chronic kidney disease: an under-recognized and under-treated problem

Patients with chronic kidney disease (CKD) almost invariably develop anaemia, which is associated with increased morbidity and mortality, and reduced quality of life. Anaemia begins early in the course of CKD, and although treatment with erythropoietin is effective, the condition is often under-treated. Because of the growing body of scientific literature on the significant morbidity and mortality associated with anaemia of CKD, a Renal Anaemia Management Period (RAMP) was proposed. This is defined as the time after onset of CKD when anaemia develops and requires early diagnosis and treatment. The RAMP was developed to call attention to the need to improve outcomes for patients with CKD and possibly lower the economic burden by correcting anaemia earlier. It is an important opportunity for preventive care and has the potential to limit costs associated with comorbidities of CKD.

Chronic kidney disease in the United States: an underrecognized problem

The continued growth of the population with end-stage renal disease (ESRD) is partially related to the underrecognition of earlier stages of chronic kidney disease (CKD) and risk factors for the development of CKD. There are several published estimates of the prevalence of CKD in the United States. From Third National Health and Nutrition Examination Survey data it has been estimated that there are 6.2 million individuals with serum creatinine levels at or above 1.5 mg/dL, or 8.3 million individuals with decreased glomerular filtration rate (<60 mL/min/1.73 m (2)). Estimates of prevalence from a health maintenance organization study suggest that there are 4.2 million Americans with persistently elevated serum creatinine levels. In addition to the high prevalence, several studies have shown that CKD is associated with increased risk for cardiovascular disease, hospitalizations, and mortality. To promote earlier detection of CKD, The National Kidney Foundation Guidelines for CKD: Evaluation, Classification and Stratification, recommended screening individuals at increased risk for CKD, such as patients with diabetes, high blood pressure, and family history of kidney disease. Therapeutic interventions to delay progression and reduce comorbidity, such as cardiovascular disease, are more likely to be effective if they are implemented early in the course of CKD.

Systemic complications of chronic kidney disease. Pinpointing clinical manifestations and best management

The kidney plays a critical role in the maintenance of homeostasis. As kidney function diminishes, excretory, regulatory, and endocrine function is lost, and complications develop in essentially every organ system. Kidney failure is the last stage in the continuum of progressive CKD. Management of the complications associated with CKD mainly includes dietary counseling, adequate control of volume and blood pressure, and use of phosphate binders, calcitriol (Calcijex, Rocaltrol), and erythropoietin. Many of these complications can be prevented or attenuated with optimal CKD care, which involves early detection of progressive kidney disease, interventions to retard its progression, prevention of uremic complications, attenuation of comorbid conditions, adequate preparation for kidney replacement therapy, and timely initiation of dialysis (figure 2). Closer attention to CKD care is likely to be the key to improved outcomes among patients with kidney failure.

Patients with Fabry disease on dialysis in the United States

BACKGROUND

: Fabry disease results from an X-linked deficiency of lysosomal alpha-galactosidase A and is a rare cause of end-stage renal disease. Little is known about the characteristics of patients with Fabry disease that initiate dialysis in the United States, although data from Europe suggests these individuals have a poor survival.

METHODS

: Using the United States Renal Disease System database, we first studied in detail 42 Fabry patients who initiated dialysis between April 1995 (following the introduction of the new detailed HCFA 2728 form) and July 1998. To examine crude survival in a larger cohort, 95 Fabry patients were studied who initiated dialysis between 1985 and 1993, similar to the European Registry. Diabetic and non-diabetic controls matched by age, gender, race, year of dialysis initiation, and initial dialysis modality were examined for comparison.

RESULTS

: During the years 1995 to 1998, the mean age of Fabry patients that initiated dialysis was 42 years, 83% were Caucasian, and 10% were African American. Despite the X-linked inheritance of Fabry disease, 12% of Fabry patients on dialysis were female. At initiation of dialysis mean serum albumin and creatinine were significantly higher and mean body mass index was significantly lower among Fabry patients, but mean glomerular filtration rate was similar to controls. Fabry patients tended to have a lower three-year survival compared to non-diabetic controls, but the results were not significantly different. In a larger cohort of Fabry patients who initiated dialysis between 1985 and 1993, the three-year survival of Fabry patients was significantly lower than non-diabetic controls: 63% (95% CI, 50 to 75%) versus 74% (95% CI, 67 to 80%; P=0.03).

CONCLUSION

: End-stage renal disease is associated with significant morbidity and mortality among patients with Fabry disease. Recent evidence that progression of Fabry disease may be attenuated by enzyme replacement therapy necessitates increased awareness of Fabry disease and its comorbidities.

Trends in anemia at initiation of dialysis in the United States

BACKGROUND

Anemia almost invariably develops in patients with chronic renal insufficiency (CRI) and is associated with a wide range of complications. The anemia of CRI can be effectively treated with recombinant human erythropoietin (rHuEPO). Recent studies suggest that the management of anemia of CRI is suboptimal in the United States.

METHODS

We examined the trends in hematocrit and rHuEPO use among all patients who started chronic dialysis therapy between April 1, 1995, and December 31, 1999, from the End-stage Renal Disease Medical Evidence Form 2728 submitted to the Health Care Financing Administration of the United States. Follow-up data containing hematocrit levels after initiation were obtained from the Medicare Part A institutional outpatient dialysis provider claims for 1990 to 1998 prevalent patients.

RESULTS

From June 1995 to June 1999, the mean hematocrit at initiation of dialysis increased from 28.1 to 29.3%. Likewise, the annual percentage of patients receiving pre-dialysis rHuEPO increased from 21.8 to 28.1%. Patients receiving predialysis rHuEPO had a higher mean hematocrit than patients without predialysis rHuEPO. The annual percentage of patients with hematocrit <24% fell 6.6% and the percentage with hematocrit > or =30% increased 9.2%. The trend toward higher hematocrit levels has been consistent across all age, gender, and race categories. Older patients, males, whites, and those who selected peritoneal dialysis had higher hematocrit levels than their counterparts. There were significant geographic differences in the prevalence of predialysis rHuEPO use.

CONCLUSION

There has been a slight improvement in the management of anemia of CRI in the United States. However, a considerable fraction of patients still have hematocrit levels that are significantly lower than the currently recommended target. Furthermore, improvement in the management of anemia could result in improved clinical outcomes among patients with CRI.

Anemia: an early complication of chronic renal insufficiency

The strong association between anemia and cardiovascular complications among patients with end-stage renal disease suggests that anemia during chronic renal insufficiency (CRI) may also have important consequences. We performed a retrospective cohort study to identify factors associated with severe anemia (hematocrit [Hct] < 30%) and examine anemia management practices in CRI. The CRI cohort was composed of 604 adult patients with elevated serum creatinine levels. There was a direct correlation between predicted glomerular filtration rate and Hct (r = 0.49) and an inverse correlation between serum creatinine level and Hct (r = -0.37). Anemia was noted early in CRI; 45% of patients with serum creatinine levels of 2 mg/dL or less had an Hct less than 36%, and 8% had an Hct less than 30%. During the course of the study, mean Hct decreased from 35.1% +/- 5.6% to 31.8% +/- 5.6%. Iron studies were obtained in only 19% of patients, and among these, the prevalence of iron deficiency (transferrin saturation < 20%) was 54%. Only 30% and 26% of patients were administered recombinant human erythropoietin (rHuEPO) and iron, respectively. Multivariate analyses showed that diabetes as the cause of renal disease, greater serum creatinine level, and having a single nephrology visit were associated with greater odds for the presence of anemia. A lower Hct and having a single nephrology visit were associated with greater odds for rHuEPO use. These results show that anemia begins early in the course of CRI, and management of anemia is suboptimal, even among patients under the care of nephrologists. Educational programs to optimize anemia management among patients with CRI are needed.

Management of patients with chronic renal insufficiency in the Northeastern United States

Comorbid conditions that develop during chronic renal insufficiency (CRI) contribute to the high morbidity and mortality among patients with end-stage renal disease (ESRD). Thus, appropriate management during CRI may lead to improved ESRD outcomes. A retrospective cohort study was performed to describe the management of patients with CRI. A total of 602 patients with CRI (creatinine > or =1.5 mg/dl for women and > or =2.0 mg/dl for men) were seen between October 1994 and September 1998 at five nephrology outpatient clinics in the Boston area. The mean (SD) age of the patients was 63 (15.5) yr, and 53% were male. At the first nephrology visit, mean (SD) serum creatinine was 3.2 (1.6) mg/dl, and mean (SD) predicted GFR was 22.3 (8.9) ml/min per 1.73 m(2). Laboratory tests for iron levels were performed in only 18% of patients, serum parathyroid hormone levels were obtained in only 15%, lipid studies were obtained in fewer than half, and among patients with diabetes, only 28% had a glycosylated hemoglobin level measured. A hematocrit <30% was present in 38%, and abnormal calcium-phosphorus metabolism was noted in 55%. Only 59% of patients who had hematocrit <30% received recombinant human erythropoietin. Among patients who received recombinant human erythropoietin, only 47% received iron. Angiotensin-converting enzyme inhibitor use was recorded for only 65% of patients with diabetes (49% of patients overall). Among patients who were known to have progressed to ESRD, only 41% had permanent access placed before initiation of dialysis. There seems to be room for improvement in the management of patients with CRI, which could result in a slower rate of progression of CRI and reduced severity of comorbid conditions.