Anemia treatment in the pre-ESRD period and associated mortality in elderly patients

Primary and specialist care interaction and referral patterns for individuals with chronic kidney disease: a narrative review

BACKGROUND

Timely referral of individuals with chronic kidney disease from primary care to secondary care is evidenced to improve patient outcomes, especially for those whose disease progresses to kidney failure requiring kidney replacement therapy. A shortage of specialist nephrology services plus no consistent criteria for referral and reporting leads to referral pattern variability in the management of individuals with chronic kidney disease.

OBJECTIVE

The objective of this review was to explore the referral patterns of individuals with chronic kidney disease from primary care to specialist nephrology services. It focused on the primary-specialist care interface, optimal timing of referral to nephrology services, adequacy of preparation for kidney replacement therapy, and the role of clinical criteria vs. risk-based prediction tools in guiding the referral process.

METHODS

A narrative review was utilised to summarise the literature, with the intent of providing a broad-based understanding of the referral patterns for patients with chronic kidney disease in order to guide clinical practice decisions. The review identified original English language qualitative, quantitative, or mixed methods publications as well as systematic reviews and meta-analyses available in PubMed and Google Scholar from their inception to 24 March 2023.

RESULTS

Thirteen papers met the criteria for detailed review. We grouped the findings into three main themes: (1) Outcomes of the timing of referral to nephrology services, (2) Adequacy of preparation for kidney replacement therapy, and (3) Comparison of clinical criteria vs. risk-based prediction tools. The review demonstrated that regardless of the time frame used to define early vs. late referral in relation to the start of kidney replacement therapy, better outcomes are evidenced in patients referred early.

CONCLUSIONS

This review informs the patterns and timing of referral for pre-dialysis specialist care to mitigate adverse outcomes for individuals with chronic kidney disease requiring dialysis. Enhancing current risk prediction equations will enable primary care clinicians to accurately predict the risk of clinically important outcomes and provide much-needed guidance on the timing of referral between primary care and specialist nephrology services.

Higher hemoglobin levels using darbepoetin alfa and kidney outcomes in advanced chronic kidney disease without diabetes: a prespecified secondary analysis of the PREDICT trial

BACKGROUND

In the primary analysis of the PREDICT trial, a higher hemoglobin target (11-13 g/dl) with darbepoetin alfa did not improve renal outcomes compared with a lower hemoglobin target (9-11 g/dl) in advanced chronic kidney disease (CKD) without diabetes. Prespecified secondary analyses were performed to further study the effects of targeting higher hemoglobin levels on renal outcomes.

METHODS

Patients with an estimated glomerular filtration rate (eGFR) 8-20 ml/min/1.73 m2 without diabetes were randomly assigned 1:1 to the high- and low-hemoglobin groups. The differences between the groups were evaluated for the following endpoints and cohort sets: eGFR and proteinuria slopes, assessed using a mixed-effects model in the full analysis set and the per-protocol set that excluded patients with off-target hemoglobin levels; the primary endpoint of composite renal outcome, evaluated in the per-protocol set using the Cox model.

RESULTS

In the full analysis set (high hemoglobin, n = 239; low hemoglobin, n = 240), eGFR and proteinuria slopes were not significantly different between the groups. In the per-protocol set (high hemoglobin, n = 136; low hemoglobin, n = 171), the high-hemoglobin group was associated with reduced composite renal outcome (adjusted hazard ratio: 0.64; 95% confidence interval: 0.43-0.96) and an improved eGFR slope (coefficient: + 1.00 ml/min/1.73 m2/year; 95% confidence interval: 0.38-1.63), while the proteinuria slope did not differ between the groups.

CONCLUSIONS

In the per-protocol set, the high-hemoglobin group demonstrated better kidney outcomes than the low-hemoglobin group, suggesting a potential benefit of maintaining higher hemoglobin levels in patients with advanced CKD without diabetes.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov (identifier: NCT01581073).

Factors affecting pre-end-stage kidney disease haemoglobin control and outcomes following dialysis initiation: a nationwide study

Background

Attaining the narrow haemoglobin (Hb) range recommended by European Renal Best Practice Guidelines renal anaemia guidelines may be difficult, and whether this leads to better outcomes following dialysis initiation is not known.

Methods

This was an observational study from the Swedish Renal Registry 2012–16, including all patients with non-dialysis-dependent chronic kidney disease (CKD) initiating renal anaemia treatment. We evaluated factors associated with off-target Hb attainment (<10 and >12 g/dL). For those who initiated dialysis, we explored associations between the pre-end-stage kidney disease (pre-ESKD) time in which Hb was within or above range, and pre-ESKD Erythropoietin Resistance Index (ERI) with the 1-year risk of death or major adverse cardiovascular events + (MACE+).

Results

About 5000 patients initiated anaemia treatment, contributing to 25 431 consecutive visits over time. Patients with polycystic kidney disease, diabetic nephropathy and nephrosclerosis, with recent bleeding/transfusion, with higher C-reactive protein or abnormal phosphate had higher odds of maintaining Hb below range. Conversely, patients with older age, CKD Stages 3b–4, pyelonephritis, kidney transplant, iron medication, higher ESA doses or abnormal serum calcium and albumin had higher odds of maintaining Hb above range. A total of 1361 patients initiated dialysis, among whom 220 deaths and 453 MACE+ occurred. A greater time spent with a pre-ESKD Hb >12 g/dL was associated with a lower risk of MACE+ (hazard ratio = 0.76; 95% confidence interval 0.61–0.94) after dialysis initiation, and a lower pre-ESKD Erythropoietin Resistance Index (ERI) was associated with improved survival (1.39; 1.02–1.90).

Conclusions

Our study identified populations that require additional efforts to control their Hb. Our outcome analysis supports the value of pre-ESKD anaemia care while illustrating the problems of ESA hyporesponsiveness in clinical practice.

Predialysis anemia management and outcomes following dialysis initiation: A retrospective cohort analysis

Whether and how anemia treatment with erythropoiesis stimulating agents (ESAs) before hemodialysis initiation may be associated with lower mortality after dialysis initiation is unknown. We compared all-cause and cardiovascular mortality in two groups of patients who experienced distinct anemia treatment patterns with ESAs before and after hemodialysis initiation. This retrospective cohort analysis included patients initiating hemodialysis April 1, 2012-June 30, 2013, identified from United States Renal Data System end-stage renal disease (ESRD) and pre-ESRD files. Patients treated with ESAs before and after hemodialysis initiation who maintained Hb ≥ 9.0 g/dL throughout (comparator group, n = 3662) were compared with patients with Hb < 9.0 g/dL before hemodialysis initiation (with or without ESAs) whose levels increased with ESAs after hemodialysis initiation (referent group, n = 4461). Cox proportional hazards models were used to calculate the hazard ratio of all-cause and cardiovascular mortality after hemodialysis initiation. Of 20,454 patients, 4855 (23.7%) had Hb < 9.0 g/dL upon hemodialysis initiation; of these 4855, 26.6% received ESAs before initiation. Comparator group Hb levels increased from 8.2 ± 0.8 mg/dL upon initiation to 10.9 ± 1.2 with ESAs afterward. Comparator patients were more likely than referent patients to be younger (76.3 ± 6.7 versus 77.2 ± 6.9 years), male (51.5% versus 49.8%), and black (24.6% versus 18.6%). Risk of all-cause mortality was lower for the comparator group versus the referent group at 3 (HR 0.83, 95% CI 0.68–1.00, P = 0.052), 6 (0.86, 0.74–1.00, P = 0.047), and 12 (0.88, 0.78–0.99, P = 0.036) months. The pattern was similar for cardiovascular mortality. Hb ≥ 9.0 with ESAs before and after hemodialysis initiation was generally associated with lower post-initiation all-cause and cardiovascular mortality compared with predialysis Hb < 9.0 g/dL in patients whose Hb levels subsequently improved with ESAs after hemodialysis initiation.

Effect of Predialysis Recombinant Human Erythropoietin on Early Survival After Hemodialysis Initiation in Patients With Chronic Kidney Disease: Co-JET Study

Progression of anemia in patients with chronic kidney disease (CKD) is associated with an increased risk of death and hospitalization. It is not sufficiently clear whether treating renal anemia with recombinant human erythropoietin (rHuEPO) has a beneficial effect on early survival after hemodialysis (HD) initiation in patients with CKD. The study was an open-label multicenter retrospective cohort study to evaluate the relationship between rHuEPO treatment and early survival after HD initiation in patients with CKD. Predialysis patients with CKD were divided into two groups: an rHuEPO-treated group (rHuEPO group) and a non-treatment group. The primary endpoint was all-cause mortality in the year after HD initiation. A total of 3261 patients were enrolled (2275 in the rHuEPO group and 986 in the non-treatment group). One-year survival was 95.36% in the rHuEPO group and 90.36% in the non-treatment group. The survival rate was significantly higher in the rHuEPO group (P < 0.0001). The results of multivariate analysis confirmed that predialysis treatment with rHuEPO is a predictor for reduced mortality risk (hazard ratio = 0.61, 95% confidence interval: 0.42-0.87, P = 0.006). Risk for the composite event of death/hospitalization was also lower in the rHuEPO group (hazard ratio = 0.88, 95% confidence interval: 0.78-0.98, P = 0.026). The results of this study suggest that treatment with rHuEPO can decrease early mortality risk after initiation of HD in patients with CKD. A prospective study is needed to further investigate early survival after HD initiation.

Anaemia and early phase cardiovascular events on haemodialysis

Although the mechanism of the cardio-renal anaemia syndrome (CRAS) has been elucidated in considerable detail over the past decade, cardiovascular disease (CVD) remains a leading cause of death among patients with end-stage kidney disease (ESKD) undergoing haemodialysis, and these patients' cardiovascular mortality is greater than that of the general population. Recent studies have reported that the CVD risk increases with advancing chronic kidney disease (CKD) stage. Furthermore, the incidence of cardiovascular events is highest during the first week after dialysis initiation, with increased risk in incident haemodialysis patients. This accumulated evidence demonstrates that how patients are managed during the pre-dialysis phase may have important implications on long-term outcomes in ESKD. Anaemia, a non-traditional risk factor for CVD, advances exponentially along with declining kidney function due to insufficient erythropoietin production. Anaemia causes functional abnormalities of the heart, as represented by cardiac hypertrophy, which results from increased cardiac workload induced by an increased preload. Left ventricular hypertrophy (LVH), a traditional risk factor for CVD, is especially associated with advanced CKD stage and could be a major risk factor for cardiovascular complications such as ischaemic heart disease, heart failure, and sudden cardiac death. In ESKD, anaemia develops more severely and requires a higher amount of erythropoiesis-stimulating agent (ESA) therapy before dialysis initiation. This suggests that improvement in anaemia management during the pre-dialysis phase may have a beneficial effect on cardiac hypertrophy and contribute to reducing the CVD risk after initiating haemodialysis.

Predialysis nephrology care and dialysis-related health outcomes among older adults initiating dialysis

BACKGROUND

Predialysis nephrology care is associated with lower mortality and rates of hospitalization following chronic dialysis initiation. Whether more frequent predialysis nephrology care is associated with other favorable outcomes for older adults is not known.

METHODS

Retrospective cohort study of patients ≥66 years who initiated chronic dialysis in 2000-2001 and were eligible for VA and/or Medicare-covered services. Nephrology visits in VA and/or Medicare during the 12-month predialysis period were identified and classified by low intensity (<3 visits), moderate intensity (3-6 visits), and high intensity (>6 visits). Outcome measures included very low estimated glomerular filtration rate, severe anemia, use of peritoneal dialysis, and receipt of permanent vascular access at dialysis initiation and death and kidney transplantation within two years of initiation. Generalized linear models with propensity score weighting were used to examine the association between nephrology care and outcomes.

RESULTS

Among 58,014 patients, 46 % had none, 22 % had low, 13 % had moderate, and 19 % had high intensity predialysis nephrology care. Patients with a greater intensity of predialysis nephrology care had more favorable outcomes (all p < 0.001). In adjusted models, patients with high intensity predialysis nephrology care were less likely to have severe anemia (RR = 0.70, 99 % CI: 0.65-0.74) and more likely to have permanent vascular access (RR = 3.60, 99 % CI: 3.42-3.79) at dialysis initiation, and less likely to die within two years of dialysis initiation (RR = 0.80, 99 % CI: 0.77-0.82).

CONCLUSION

In a large cohort of older adults treated with chronic dialysis, greater intensity of predialysis nephrology care was associated with more favorable outcomes.

Anaemia management and mortality risk in newly visiting patients with chronic kidney disease in Japan: The CKD-ROUTE study

AIM

To investigate the association between iron deficiency anaemia and mortality risk and assess the changes in anaemia and iron status after primary management by a nephrologist.

METHODS

In this prospective cohort study, we stratified 951 non-dialysis chronic kidney disease (CKD) G2-G5 patients newly visiting 16 nephrology centres into four groups according to the presence of anaemia with or without iron deficiency. All-cause mortality, cardiovascular (CV)-related mortality, and a change in anaemia and iron status after specialized primary care were the endpoints evaluated.

RESULTS

During a median follow-up time of 19 months, the number of all-cause deaths and CV-related deaths were 56 and 26, respectively. Compared with the control group, the groups with isolated anaemia and iron deficiency anaemia had significantly higher all-cause mortalities (isolated anaemia: hazard ratio (HR), 3.37; 95% confidence intervals (CI), 1.76-6.44; iron deficiency anaemia: HR, 3.11; 95% CI, 1.21-8.01) and CV-related mortalities (isolated anaemia: HR, 3.64; 95% CI, 1.36-9.73; iron deficiency anaemia: HR, 3.86; 95% CI, 1.11-13.41). In the isolated anaemia group, erythropoietin-stimulating agent (ESA) prescriptions significantly increased to approximately 70%. However, in patients with both anaemia and iron deficiency, iron prescriptions only increased to 48.1%.

CONCLUSIONS

Iron deficiency anaemia and isolated anaemia were associated with all-cause and CV-related mortality. The absence of relative increase in iron prescriptions suggests that iron deficiency should be accurately assessed and iron supplementation should be appropriately used to manage anaemia in non-dialysis patients with CKD.

Leptin in chronic kidney disease: a link between hematopoiesis, bone metabolism, and nutrition

Anemia, dyslipidemia, malnutrition, together with mineral and bone disorders are common complications in patients with chronic kidney disease (CKD). All are associated with increased risk of mortality. Leptin is a small peptide hormone that is mainly but not exclusively produced in adipose tissue. It is also secreted by normal human osteoblasts, subchondral osteoblasts, placental syncytiotrophoblasts, and the gastric epithelium. Leptin binds to its receptors in the hypothalamus to regulate bone metabolism and food intake. Leptin also has several other important metabolic effects on peripheral tissues, including the liver, skeletal muscle, and bone marrow. Leptin is cleared principally by the kidney. Not surprisingly, serum leptin appears to increase concurrently with declines in the glomerular filtration rate in patients with CKD. A growing body of evidence suggests that leptin might be closely related to hematopoiesis, nutrition, and bone metabolism in CKD patients. Results are conflicting regarding leptin in patients with CKD, in whom both beneficial and detrimental effects on uremia outcome are found. This review elucidates the discovery of leptin and its receptors, changes in serum or plasma leptin levels, the functions of leptin, relationships between leptin and the complications mentioned above, and pharmaceutical interventions in serum leptin levels in patients with CKD.

Chronic renal failure complications and management in kidney transplanted and nontransplanted patients

BACKGROUND

Our purpose was to compare the management of chronic kidney disease (CKD) according to Kidney Disease Quality Initiative (K/DOQI) recommendations in kidney transplanted patients (T) and nontransplanted ones (NT).

METHODS

Data concerning CKD complications were collected retrospectively. Patients seen in consultations in our department from May 2009 to June 2010 were selected if they had at least 6 months of follow-up, CKD stage 4 or 5, and no exclusion criteria namely hospitalization, active cancer, or infection in the 3 months before data collection.

RESULTS

Fifty-eight T were compared with 85 NT matched by CKD stage (4-5). Anemia within K/DOQI target was better controlled among NT (51.2% versus 41.3%); however, ferritin levels within K/DOQI target were higher (80% T versus 51.7% NT). Average arterial blood pressure was similar in both groups but 51.7% of T were in K/DOQI target versus 41% of NT. Dyslipidemia within cholesterol K/DOQI target was better controlled in 60% (NT) versus 35% NT with 63.5% versus 38% NT within low-density lipoprotein K/DOQI targets. Phosphorus level was better controlled among T; parathyroid was better controlled in among 65% NT versus 50% T within the target level.

CONCLUSION

Most complications of CKD were better managed among NT.

Trends in relative mortality between Hispanic and non-Hispanic whites initiating dialysis: a retrospective study of the US Renal Data System

BACKGROUND

Hispanic patients undergoing long-term dialysis experience better survival compared with non-Hispanic whites. It is unknown whether this association differs by age, has changed over time, or is due to differential access to kidney transplantation.

STUDY DESIGN

National retrospective cohort study.

SETTING & PARTICIPANTS

Using the US Renal Data System, we identified 615,618 white patients 18 years or older who initiated dialysis therapy between January 1, 1995, and December 31, 2007.

PREDICTORS

Hispanic ethnicity (vs non-Hispanic whites), year of end-stage renal disease incidence, age (as potential effect modifier).

OUTCOMES

All-cause and cause-specific mortality.

RESULTS

We found that Hispanics initiating dialysis therapy experienced lower mortality, but age modified this association (P < 0.001). Compared with non-Hispanic whites, mortality in Hispanics was 33% lower at ages 18-39 years (adjusted cause-specific HR [HRcs], 0.67; 95% CI, 0.64-0.71) and 40-59 years (HRcs, 0.67; 95% CI, 0.66-0.68), 19% lower at ages 60-79 years (HRcs, 0.81; 95% CI, 0.80-0.82), and 6% lower at 80 years or older (HRcs, 0.94; 95% CI, 0.91-0.97). Accounting for the differential rates of kidney transplantation, the associations were attenuated markedly in the younger age strata; the survival benefit for Hispanics was reduced from 33% to 10% at ages 18-39 years (adjusted subdistribution-specific HR [HRsd], 0.90; 95% CI, 0.85-0.94) and from 33% to 19% among those aged 40-59 years (HRsd, 0.81; 95% CI, 0.80-0.83).

LIMITATIONS

Inability to analyze Hispanic subgroups that may experience heterogeneous mortality outcomes.

CONCLUSIONS

Overall, Hispanics experienced lower mortality, but differential access to kidney transplantation was responsible for much of the apparent survival benefit noted in younger Hispanics.

Hispanic ethnicity and vascular access use in patients initiating hemodialysis in the United States

BACKGROUND AND OBJECTIVES

Hispanics are the largest minority in the United States (comprising 16.3% of the US population) and have 1.5 times the age-, sex-, and race-adjusted incidence of ESRD compared with non-Hispanics. Poor health care access and low-quality care generally received by Hispanics are well documented. However, little is known regarding dialysis preparation of Hispanic patients with progressive CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using data from Medical Evidence Report form CMS-2728-U3, 321,996 adult patients of white or black race were identified who initiated hemodialysis (HD) between July 1, 2005 and December 31, 2008. The form captures Hispanic ethnicity, vascular access use at first outpatient HD, sociodemographic characteristics, and comorbidities. This study also examined whether use of an arteriovenous fistula (AVF) or graft (AVG) was reported.

RESULTS

AVF/AVG use was reported in 14.5% of Hispanics and 17.6% in non-Hispanics (P<0.001). The unadjusted prevalence ratio (PR) was 0.85 (95% confidence interval [95% CI], 0.83-0.88), indicating that Hispanics were 15% less likely to use AVG/AVF for their first outpatient HD. Adjustment for age, sex, and race, as well as a large number of comorbidities and frailty indicators, did not change this association (PR, 0.85; 95% CI, 0.83-0.88). Further adjustment for timing of first predialysis nephrology care, however, attenuated the PR by two-thirds (PR, 0.94; 95% CI, 0.92-0.97).

CONCLUSIONS

Hispanics are less likely to use arteriovenous access for first outpatient HD compared with non-Hispanics, which seems to be explained by variation in the access to predialysis nephrology care.

Complications of progression of CKD

CKD is a complex comorbid condition with multiple manifestations. It is closely linked with cardiovascular disease and has a very high mortality rate. Currently, it consumes 28% of Medicare expenditures. Complications of CKD include hypertension, diabetes, dyslipidemia, cardiovascular disease, anemia, and bone and mineral disorders. It is underrecognized and underdiagnosed in primary care offices. There is strong evidence that controlling blood pressure, blood glucose, and use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in albuminuric patients, as well as referral to the nephrologist when glomerular filtration rate is <30 mL/min/1.73 m(2), is associated with lower mortality, better access to kidney transplantation, improved management of comorbidities, and less frequent use of catheters for dialysis and to lower mortality.

Individualizing anaemia therapy

Individualized strategies for managing renal anaemia with erythropoiesis-stimulating agents (ESAs) need to be advanced. Recent outcomes from clinical studies prompted a narrowing of the guideline-recommended haemoglobin target (11-12 g/dL) due to increased mortality and morbidity when targeting higher haemoglobin concentrations. Maintaining a narrow target is a clinical challenge, as haemoglobin concentration tends to fluctuate. The goal of individualized treatment is to achieve the haemoglobin target at the lowest ESA dose while avoiding significant fluctuations in haemoglobin concentrations and persistently low or high concentrations. This may require changes to the ESA dose and dosing frequency over the course of treatment.

Biosimilar epoetins and other "follow-on" biologics: update on the European experiences

After the patents of biopharmaceuticals have expired, based on specific regulatory approval pathways copied products ("biosimilars" or "follow-on biologics") have been launched in the EU. This article summarizes experiences with hematopoietic medicines, namely the epoetins (two biosimilars traded under five different brand names) and the filgrastims (two biosimilars, six brand names). Physicians and pharmacists should be familiar with the legal and pharmacological specialities of biosimilars: The production process can differ from that of the original, clinical indications can be extrapolated, glycoproteins contain varying isoforms, the formulation may differ from the original, and biopharmaceuticals are potentially immunogenic. Only on proof of quality, efficacy and safety, biosimilars are a viable option because of their lower costs.

Timing of erythropoiesis-stimulating agent initiation and adverse outcomes in nondialysis CKD: a propensity-matched observational study

BACKGROUND AND OBJECTIVES

The severity of anemia at which to initiate erythropoiesis-stimulating agent (ESA) treatment in nondialysis chronic kidney disease (CKD) patients is unclear. Risk of mortality, hospitalizations, and blood transfusion were compared among nondialysis CKD patients with "early" versus "delayed" ESA initiation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A retrospective cohort study was conducted on CKD (estimated GFR <60 ml/min/1.73m(2)) outpatients in the national Veterans Administration who were initiated on ESAs. Patients with ESRD, gastrointestinal bleeding, chemotherapy, or hematologic malignancy were excluded. Patients were characterized as having early [hemoglobin (Hb) 10.0 to 11.0 g/dl] or delayed (Hb 8.0 to 9.9 g/dl) ESA initiation. A propensity score comprising demographic, clinical, and laboratory variables was used to select a 1:1 matched cohort. Cox survival and negative binomial regression were used to compare the matched groups for all-cause mortality, hospitalizations, and blood transfusions.

RESULTS

Of 1837 patients who met inclusion criteria, 1410 (77%) were successfully matched. The groups did not differ significantly in 31 characteristics reflecting sociodemographics, comorbidity, healthcare utilization, and renal function. There was no significant difference in mortality with early initiation. Those initiated early had a 17% lower risk of initial hospitalization and a 29% lower risk of transfusion compared with delayed initiation patients. Results did not differ between those with and without pre-ESA transfusion or hospitalization.

CONCLUSIONS

In nondialysis CKD, ESA initiation at Hb 10.0 to 11.0 g/dl compared with 8.0 to 9.9 g/dl is associated with reduced risk of blood transfusion and initial hospitalization.

Peri- and postnatal rodent development of Hematide, an erythropoiesis-stimulating agent

BACKGROUND

Aperi- and postnatal reproduction toxicity study was conducted in rats treated with Hematide, a synthetic PEGylated peptidic erythropoiesis stimulating agent (ESA).

METHODS

Hematide, at IV doses of 0, 0.5, 3, and 15 mg/kg, was administered from implantation through lactation on gestation days (GDs) 5 and 18 and lactation day (LD) 13.

RESULTS

Hematide induced pronounced polycythemia in all Hematide-treated dams. On LDs 2 and 21, hemoglobin (Hgb) increases above control levels were 3.1, 5.2, and 5.0 g/dL and 4.1, 5.1, and 5.5 g/dL at the 0.5, 3, and 15 mg/kg/dose, respectively. There were no effects on parturition, lactation, or maternal behavior in the F0 generation female rats. A slight decrease in pup viability on postpartum days 2-4 and lower body weights and/or body weight gain for the F1 generation were associated with pronounced polycythemia and decreases in maternal body weight gain and/or food consumption at > or =3 mg/kg/dose. Hematide fetal exposure was negligible. No Hematide effect, other than on growth and survival, was noted on developmental, functional, mating, and fertility end points in the F1 generation rats, and no effect on litter or fetal parameters was observed in the F2 generation. The maternal no-observed-adverse-effect level (NOAEL) for Hematide was 0.5 mg/kg, and the NOAEL for parturition and maternal behavior was 15 mg/kg. The NOAEL for F1 pup viability and growth was 0.5 mg/kg/dose.

CONCLUSIONS

In conclusion, the Hematide-associated adverse findings were attributed to exaggerated erythropoiesis (pronounced and prolonged polycythemia) resulting from administration of an ESA to pregnant animals.

Negative trials in nephrology: what can we learn?

Chronic kidney disease is assuming epidemic proportions, and an increasing number of clinical trials are testing treatments developed to improve morbidity and mortality. Surprisingly, however, a large proportion of these trials have had negative or neutral results. When trials unexpectedly demonstrate either no benefit or a detrimental impact of a treatment, especially when that treatment is already used in practice, critics commonly argue that the results were dictated by flawed trial design rather than the intrinsic properties of the treatment. In kidney disease therapeutics, trials commonly rely on observational data and test the hypothesis that these associations may be extrapolated to cause-and-effect. Other key issues in trial design that may affect outcomes include the impact of enrolling relatively healthier subjects, the complexity of recruiting participants with specific characteristics while maintaining generalizability, and the subtleties of event adjudication and quality of life assessments. In this article, general principles of trial design will be discussed and the potential lessons learned from recent trials in nephrology will be critically reviewed.

Extended administration of erythropoiesis-stimulating agents for optimising the management of renal anaemia: what is the evidence?

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) have transformed the management of anaemia in patients with chronic kidney disease (CKD), reducing transfusion requirements and leading to improved quality of life. However, effective anaemia management with current ESAs is labour-intensive and time-consuming. Approaches are required to simplify anaemia management and reduce the burden on healthcare systems. There is increasing interest in extending the administration interval of ESAs. This would result in considerable time-savings, reducing the workload of healthcare providers and potentially reducing healthcare system costs. Time saved could be utilised in improving other aspects of patient care, such as implementation of guidelines, or treating more patients. Potential benefits of extended administration intervals for patients include a less demanding regimen and fewer injections, which could lead to improved adherence to treatment.

AIM

This article reviews studies of the efficacy of current ESAs in maintaining stable haemoglobin (Hb) levels when used at extended administration intervals of up to once monthly.

SUMMARY OF FINDING

Patients who are already stable on more frequent ESA therapy and who respond well to treatment may be able to maintain stable Hb with extended dosing regimens with established ESAs. However, few patients with CKD currently receive ESAs once-monthly in clinical practice. New agents with long half-lives offer the potential for extended dosing regimens in all patients with CKD.

The effect of severe hepatic impairment on the pharmacokinetics and haematological response of C.E.R.A

AIM

To examine the effect of severe hepatic impairment (HI) on the pharmacokinetics (PK) and pharmacodynamics (PD) of the continuous erythropoietin receptor activator, C.E.R.A.

METHODS

A non-randomised, multicentre, single-dose, open-label study in patients with HI (n=12) and healthy subjects (n=12). After 2 weeks of screening, participants received a single intravenous dose of C.E.R.A. (200 mug), and were then followed for approximately 8 weeks. The area under the concentration-time curve (AUC) from drug administration to last measurable concentration (AUC(last)), and maximum C.E.R.A. concentration (C(max)) were calculated to assess PK. The baseline-corrected area under the effect curve over 22 days (AUE(corr)) for reticulocyte count was the primary PD parameter.

RESULTS

The PK profile was similar in patients and healthy subjects (AUC(last): 6678 vs 6985 ng*h/mL; C(max): 63 vs 75 ng/mL) C.E.R.A. produced a sustained erythropoietic response in bothgroups, with increases in reticulocyte counts peaking 7-9 days post-dose and returning to baseline by Day 22. Although mean AUE(corr) was 64% lower in patients, this may have been an artefact of higher baseline reticulocyte counts. Lower reticulocyte responses in patients did not translate into lower responses for haemoglobin, haematocrit or erythrocytes, suggesting that HI had no clinically relevant effect on the PD of C.E.R.A. C.E.R.A. was well tolerated. Four AEs (none considered drug related) were reported in three patients (mild myocardial ischaemia; mild pyrexia and liver transplant; severe bacterial peritonitis [serious AE]); no AEs were reported in healthy subjects.

CONCLUSIONS

Severe HI has no clinically relevant effect on PK parameters or haematological response after single-dose C.E.R.A.

Anemia of Chronic Kidney Disease

Chronic kidney disease may result in complete kidney failure and contribute to many other health issues. Anemia is a logical consequence of the disease because the kidneys are the primary source of erythropoietin, the hormone that acts to stimulate red blood cell production in the bone marrow. All patients with chronic kidney disease are at risk for anemia, and treating anemia is extremely important to their health and well-being. Preventing or reversing the effects of anemia on the heart may decrease morbidity and mortality and improve quality of life. Many patients fail to receive treatment for anemia before requiring renal replacement therapy for end-stage renal disease. Pharmacists can play a vital role in screening, evaluating, designing proper treatment regimens, and monitoring patients with anemia of chronic kidney disease. Current recommendations regarding anemia are reviewed, including evaluation, pharmacotherapeutic agents, monitoring parameters, and goals of therapy.

Outcomes in patients with chronic kidney disease referred late to nephrologists: a meta-analysis

PURPOSE

The study purpose was to compare differences in mortality and the duration of hospitalization in patients with chronic kidney disease who are referred early versus late to nephrologists.

METHODS

We searched English-language literature from 1980 through December 2005, along with national conference proceedings, the Web of Science Citation Index, and reference lists of all included studies. Twenty-two studies with a total sample size of 12,749 met inclusion criteria.

RESULTS

There was significantly increased overall mortality in the late referral group as compared with the early referral group (relative risk 1.99; 95% confidence interval [CI], 1.66 to 2.39, P <.0001). The duration of hospital stay, at the time of initiation of renal replacement therapy, was greater in the late referred group by an average of 12 days (95% CI, 8.0 to 16.1, P=.0007). Significant heterogeneity was detected for both outcomes.

CONCLUSION

Timing of referral emerged to be a significant factor impacting homogeneity in the mortality outcome. Our results suggest significantly higher mortality and increased early hospitalization of chronic kidney disease subjects referred late to nephrologists as compared with earlier referred subjects.

Intravenous methoxy polyethylene glycol-epoetin beta for haemoglobin control in patients with chronic kidney disease who are on dialysis: a randomised non-inferiority trial (MAXIMA)

BACKGROUND

Conventional treatment with epoetin to manage anaemia in chronic kidney disease needs frequent administrations, changes of dose, and close monitoring of haemoglobin concentrations. We aimed to compare the effectiveness of methoxy polyethylene glycol-epoetin beta, given intravenously at 2-week or 4-week intervals, with epoetin treatment one to three times per week for haemoglobin control in haemodialysis patients.

METHODS

We screened 1115 adult patients from 96 centres who had stable chronic renal anaemia and were on dialysis treatment and intravenous maintenance epoetin. We did an open-label, parallel-group, non-inferiority trial to compare two dosing intervals of methoxy polyethylene glycol-epoetin beta with standard epoetin treatment. We established baseline haemoglobin concentration and eligibility over a 4-week run-in period. 223 patients were randomly assigned to receive methoxy polyethylene glycol-epoetin beta every 2 weeks, and 224 to receive it every 4 weeks. The initial dose was based on the average epoetin dose given during the week before the switch. The primary endpoint was change in haemoglobin concentration between baseline and the assessment period. We analysed patients both by intention to treat and per protocol. This study is registered with ClinicalTrials.gov, number NCT00077610.

FINDINGS

We excluded 133 of the 673 randomised patients from the per-protocol analysis because they had inadequate iron status or fewer than five haemoglobin measurements during the assessment period or needed red blood cell transfusions. The mean change from baseline haemoglobin for patients who had switched to intravenous methoxy polyethylene glycol-epoetin beta every 2 weeks (-0.71 g/L, 95% CI -2.20 to 0.77) or every 4 weeks (-0.25 g/L, -1.79 to 1.29) was non-inferior to the mean change for patients who continued treatment with epoetin (-0.75 g/L, -2.26 to 0.75) (p<0.0001 for both comparisons). Of the 666 patients who received at least one dose of study drug, the incidence of adverse events or serious adverse events did not differ between groups (p=0.30 and p=0.40, respectively).

INTERPRETATION

This long-acting erythropoiesis-stimulating agent is as safe as conventional epoetin treatment, and can maintain anaemia management in haemodialysis patients when given intravenously at 4-week dosing intervals.

Stability of target hemoglobin levels during the first year of epoetin treatment in patients with chronic kidney disease

BACKGROUND AND OBJECTIVES

Instability of hemoglobin levels during epoetin therapy is a new problem in hemodialysis. We evaluated extent and correlates of time in target, that is, the time spent with hemoglobin > or = 11 g/dl during the first year of epoetin and its association with renal survival.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data were collected in 917 visits for 12.0 mo in 119 patients with chronic kidney disease; thereafter, patients started renal survival analysis for 10.1 mo. At baseline, hemoglobin was 10.0 +/- 0.8 g/dl and GFR was 22.1 +/- 14.2 ml/min per 1.73 m2.

RESULTS

Hemoglobin target, reached in 1.5 mo, was steadily maintained in only 24% of patients. Time in target was not merely due to differences in time to target; after first achievement of target, in fact, a reduction of hemoglobin < 11 g/dl occurred in 51% of patients. At multivariate analysis, male gender, basal GFR and hemoglobin levels, first epoetin dose, and iron supplementation were directly associated with length of time in target. A lower risk for renal death (dialysis n = 53; death n = 8) was detected in the higher tertile of time in target (11.3 mo) versus lower tertile (3.2 mo). This difference persisted at Cox analysis after adjustment for age, gender, GFR, BP, and proteinuria.

CONCLUSIONS

In chronic kidney disease, time in target during the first year of epoetin therapy is frequently short depending not only on time to target but also on post-target hemoglobin reductions, correlates with male gender, timing, and intensity of initial therapy and is coupled with better renal survival.

The economic impact of epoetin alfa therapy on delaying time to dialysis in elderly patients with chronic kidney disease

The aim of this study was to evaluate the impact of epoetin alfa (EPO) therapy on delaying progression to renal dialysis and quantify the associated medical cost savings in elderly chronic kidney disease (CKD) patients. Elderly (>/=65 years) dialysis patients who had >/=1 hemoglobin (Hb) value and >/=1 glomerular filtration rate (GFR) value of <60 mL/min/1.73 m(2) were identified using health claims and laboratory data from the period January 1999 to February 2005. Exclusion criteria included: organ transplantation, blood transfusion, use of darbepoetin alfa, and dialysis for reasons other than CKD. Each EPO patient was matched by Hb and GFR to one control patient. The time from when matched patients had the same GFR value to dialysis was compared. The economic impact of EPO on delaying dialysis was monetized using standardized health plan payments, and adjusted to 2005 United States dollars. Sixty-eight patients (34 EPO and 34 matched controls) formed the study population. The average time to dialysis was 156 days longer for the EPO group compared to the matched control group (p = 0.003). Analysis by CKD severity revealed that EPO therapy in less severe CKD patients offered a greater delay in time to dialysis (Stage 4: 213 days difference, p = 0.003; Stage 5: 104 days difference, p = 0.160). EPO treatment resulted in cost savings of $43,374-$59,222 per patient compared to non-EPO matched controls. This retrospective matched cohort study suggests that EPO therapy has a beneficial impact on delaying progression to dialysis in elderly CKD patients, especially in those with less severe CKD.

Diabetic nephropathy in the elderly

Renal impairment is frequent in aged diabetic patients, notably with type 2 diabetes. It results from a multifactorial pathogeny, particularly the combined actions of hyperglycaemia, arterial hypertension and ageing. Diabetic nephropathy (DN) is associated with an increased cardiovascular mortality. DN often leads to end stage renal failure (ESRF) which causes specific problems of decision and practical organization of extra-renal epuration in diabetic and aged patients. In the absence of renal biopsy, clinical signs are often insufficient to assess the diabetic origin of a nephropathy in an elderly diabetic patient. Prevention of DN is principally based on tight glycaemic and blood pressure control. The progression of renal lesions can be retarded by strict blood pressure control, notably by blocking of the renin-angiotensin system, if well tolerated in aged patients. It is absolutely necessary to avoid the worsening of renal lesions by potentially nephrotoxic products, notably non steroidal anti-inflammatory drugs (NSAIDs) and iodinated contrast media. At the stage of renal failure, it is important to adapt the antidiabetic treatment, and in the majority of the cases, to switch to insulin when glomerular filtration rate (GFR) is below 30 ml/mn/1.73 m2.

Target level for hemoglobin correction in patients with diabetes and CKD: primary results of the Anemia Correction in Diabetes (ACORD) Study

BACKGROUND

Patients with diabetes and anemia are at high risk of cardiovascular disease. The Anemia CORrection in Diabetes (ACORD) Study aimed to investigate the effect of anemia correction on cardiac structure, function, and outcomes in patients with diabetes with anemia and early diabetic nephropathy.

METHODS

One hundred seventy-two patients with type 1 or 2 diabetes mellitus, mild to moderate anemia, and stage 1 to 3 chronic kidney disease were randomly assigned to attain a target hemoglobin (Hb) level of either 13 to 15 g/dL (130 to 150 g/L; group 1) or 10.5 to 11.5 g/dL (105 to 115 g/L; group 2). The primary end point was change in left ventricular mass index (LVMI). Secondary end points included echocardiographic variables, renal function, quality of life, and safety.

RESULTS

Median Hb level and LVMI were similar in groups 1 and 2 (Hb, 11.9 and 11.7 g/dL [119 and 117 g/L]; LVMI, 113.5 and 112.3 g/m(2), respectively). At study end, Hb levels were 13.5 g/dL (135 g/L) in group 1 and 12.1 g/dL (121 g/L) in group 2 (P < 0.001). No significant differences were observed in median LVMI at month 15 between study groups (group 1, 112.3 g/m(2); group 2, 116.5 g/m(2)). Multivariate analysis showed a nonsignificant decrease in LVMI (P = 0.15) in group 1 versus group 2. Anemia correction had no effect on the rate of decrease in creatinine clearance, but resulted in significantly improved quality of life in group 1 (P = 0.04). There were no clinically relevant differences in adverse events between study groups.

CONCLUSION

In patients with diabetes with mild to moderate anemia and moderate left ventricular hypertrophy, correction to an Hb target level of 13 to 15 g/dL (130 to 150 g/L) does not decrease LVMI. However, normalization of Hb level prevented an additional increase in left ventricular hypertrophy, was safe, and improved quality of life.

Anemia, chronic renal disease and congestive heart failure--the cardio renal anemia syndrome: the need for cooperation between cardiologists and nephrologists

Many patients with congestive heart failure (CHF) fail to respond to maximal CHF therapy and progress to end stage CHF with many hospitalizations, poor quality of life (QoL), progressive chronic kidney disease (CKD) which can lead to end stage kidney disease (ESKD), or die of cardiovascular complications within a short time. One factor that has generally been ignored in many of these people is the fact that they are often anemic. The anemia in CHF is due mainly to the frequently-associated CKD but also to the inhibitory effects of cytokines on erythropoietin production and on bone marrow activity, as well as to their interference with iron absorption from the gut and their inhibiting effect on the release of iron from iron stores. Anemia itself may further worsen cardiac and renal function and make the patients resistant to standard CHF therapy. Indeed anemia in CHF has been associated with increased severity of CHF, increased hospitalization, worse cardiac function and functional class, the need for higher doses of diuretics, progressive worsening of renal function and reduced QoL. In both controlled and uncontrolled studies of CHF, the correction of the anemia with erythropoietin (EPO) and oral or intravenous (IV) iron has been associated with improvement in many cardiac and renal parameters and an increased QoL. EPO itself may also play a direct role in improving the heart unrelated to the improvement of the anemia--by reducing apoptosis of cardiac and endothelial cells, increasing the number of endothelial progenitor cells, and improving endothelial cell function and neovascularization of the heart. Anemia may also play a role in the worsening of acute myocardial infarction and chronic coronary heart disease (CHD) and in the cardiovascular complications of renal transplantation. Anemia, CHF and CKD interact as a vicious circle so as to cause or worsen each other- the so-called cardio renal anemia syndrome. Only adequate treatment of all three conditions can prevent the CHF and CKD from progressing.

Chronic kidney disease care delivered by US family medicine and internal medicine trainees: results from an online survey

BACKGROUND

Complications of chronic kidney disease (CKD) contribute to morbidity and mortality. Consequently, treatment guidelines have been developed to facilitate early detection and treatment. However, given the high prevalence of CKD, many patients with early CKD are seen by non-nephrologists, who need to be aware of CKD complications, screening methods and treatment goals in order to initiate timely therapy and referral.

METHODS

We performed a web-based survey to assess perceptions and practice patterns in CKD care among 376 family medicine and internal medicine trainees in the United States. Questions were focused on the identification of CKD risk factors, screening for CKD and associated co-morbidities, as well as management of anemia and secondary hyperparathyroidism in patients with CKD.

RESULTS

Our data show that CKD risk factors are not universally recognized, screening for CKD complications is not generally taken into consideration, and that the management of anemia and secondary hyperparathyroidism poses major diagnostic and therapeutic difficulties for trainees.

CONCLUSION

Educational efforts are needed to raise awareness of clinical practice guidelines and recommendations for patients with CKD among future practitioners.

Continuous Erythropoietin Receptor Activator (C.E.R.A.) administered at extended administration intervals corrects anaemia in patients with chronic kidney disease on dialysis: a randomised, multicentre, multiple-dose, phase II study

This dose-finding, open-label study examined the potential of subcutaneous Continuous Erythropoietin Receptor Activator (C.E.R.A.) to correct anaemia at extended administration intervals in 61 erythropoiesis-stimulating agent-naïve patients with chronic kidney disease (CKD) on dialysis. After a 4-week run-in, patients were randomised to C.E.R.A. 0.15, 0.30 and 0.45 microg/kg/week. Within these dose groups, patients were further randomised to once weekly, once every 2 weeks or once every 3 weeks treatment. Mean changes in haemoglobin (Hb) increased with increasing C.E.R.A. dose during a period of 6 weeks where no dose adjustments were permitted. The effect was independent of administration schedule. Erythropoietic responses were sustained until the end of the study (12 weeks) in all groups. In total, 90% of patients in the 0.30 microg/kg/week group and 79% in the 0.45 microg/kg/week group responded to treatment (Hb increase > or =1.0 g/dl), compared with 72% in the 0.15 microg/kg/week group. Faster median response time was associated with increasing dose (51, 38 and 31 days, respectively) and response was unrelated to administration frequency. C.E.R.A. was generally well tolerated. Our results suggest that 0.60 microg/kg twice monthly would be a suitable starting dose of C.E.R.A. for the initiation of anaemia correction in patients with CKD on dialysis. Phase III studies will confirm the feasibility of using C.E.R.A. at extended administration intervals in patients with CKD and anaemia.

Correction of anemia with epoetin alfa in chronic kidney disease

BACKGROUND

Anemia, a common complication of chronic kidney disease, usually develops as a consequence of erythropoietin deficiency. Recombinant human erythropoietin (epoetin alfa) is indicated for the correction of anemia associated with this condition. However, the optimal level of hemoglobin correction is not defined.

METHODS

In this open-label trial, we studied 1432 patients with chronic kidney disease, 715 of whom were randomly assigned to receive a dose of epoetin alfa targeted to achieve a hemoglobin level of 13.5 g per deciliter and 717 of whom were assigned to receive a dose targeted to achieve a level of 11.3 g per deciliter. The median study duration was 16 months. The primary end point was a composite of death, myocardial infarction, hospitalization for congestive heart failure (without renal replacement therapy), and stroke.

RESULTS

A total of 222 composite events occurred: 125 events in the high-hemoglobin group, as compared with 97 events in the low-hemoglobin group (hazard ratio, 1.34; 95% confidence interval, 1.03 to 1.74; P=0.03). There were 65 deaths (29.3%), 101 hospitalizations for congestive heart failure (45.5%), 25 myocardial infarctions (11.3%), and 23 strokes (10.4%). Seven patients (3.2%) were hospitalized for congestive heart failure and myocardial infarction combined, and one patient (0.5%) died after having a stroke. Improvements in the quality of life were similar in the two groups. More patients in the high-hemoglobin group had at least one serious adverse event.

CONCLUSIONS

The use of a target hemoglobin level of 13.5 g per deciliter (as compared with 11.3 g per deciliter) was associated with increased risk and no incremental improvement in the quality of life. (ClinicalTrials.gov number, NCT00211120 [ClinicalTrials.gov].).

Global approach to cardiovascular risk in chronic kidney disease: reality and opportunities for intervention

The current implementation into nephrology clinical practice of guidelines on treatment of cardiovascular (CV) risk factors in chronic kidney disease (CKD) is unknown. We designed a cross-sectional analysis to evaluate the prevalence and treatment of eight modifiable CV risk factors in 1058 predialysis CKD patients (stage 3: n=486; stage 4: n=430, stage 5: n=142) followed for at least 1 year in 26 Italian renal clinics. The median nephrology follow-up was 37 months (range: 12-391 months). From stages 3 to 5, hypertension was the main complication (89, 87, and 87%), whereas smoking, high calcium-phosphate product and malnutrition were uncommon. The prevalence of proteinuria (25, 38, and 58%), anemia (16, 32, and 51%) and left ventricular hypertrophy (51, 55, and 64%) significantly increased, while hypercholesterolemia was less frequent in stage 5 (49%) than in stages 4 and 3 (59%). The vast majority of patients received multidrug antihypertensive therapy including inhibitors of renin-angiotensin system; conversely, diuretic treatment was consistently inadequate for both frequency and dose despite scarce implementation of low salt diet (19%). Statins were not prescribed in most hypercholesterolemics (78%), and epoietin treatment was largely overlooked in anemics (78%). The adjusted risk for having a higher number of uncontrolled risk factors rose in the presence of diabetes (odds ratio 1.29, 95% confidence interval 1.00-1.66), history of CV disease (odds ratio 1.48, 95% confidence interval 1.15-1.90) and CKD stages 4 and 5 (odds ratio 1.75, 95% confidence interval 1.37-2.22 and odds ratio 2.85, 95% confidence interval 2.01-4.04, respectively). In the tertiary care of CKD, treatment of hypertension is largely inadequate, whereas therapy of anemia and dyslipidemia is frequently omitted. The risk of not achieving therapeutic targets is higher in patients with diabetes, CV disease and more advanced CKD.

Evidence-based systematic literature review of hemoglobin/hematocrit and all-cause mortality in dialysis patients

BACKGROUND

An evidence-based evaluation of peer-reviewed original research published during 1980 to 2004 and examining the relationship between hemoglobin and/or hematocrit values and all-cause mortality in dialysis patients was conducted to compare the studies' designs, analytic strategies, and results.

METHODS

The search targeted MEDLINE and EMBASE and included publications referenced in the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative Anemia Guidelines. Both randomized clinical trials (RCTs) and observational studies were considered.

RESULTS

Of 7 RCTs and 20 observational studies identified, 5 trials and 13 studies were included in evidence tables. The trials were underpowered to study mortality and enrolled different patient populations, limiting their generalizability. Although none reached statistical significance, trials focusing on a general dialysis population tended to show either no effect or a benefit of greater hemoglobin level target, whereas trials enrolling cardiac patients suggested increased mortality associated with greater hemoglobin levels. The observational studies were heterogeneous in design, used varying exposure categorizations, and controlled for different covariates, but generally were supportive of increased mortality associated with a hemoglobin level less than the reference range. Evidence of benefits or risks of hemoglobin levels greater than the reference was variable.

CONCLUSION

RCT-based evidence relating hemoglobin and/or hematocrit values to mortality in dialysis patients is limited. The relationship may be modified by the presence of preexisting conditions (cardiac disease). The published literature is insufficient for generalization of risks or benefits of a hemoglobin level greater than 11 to 12 g/dL (>110 to 120 g/L). There is a need for better designed RCTs focusing on mortality as a primary outcome and enrolling patients without cardiac disease. Observational studies should adequately control for relevant confounders (eg, baseline comorbidities) and assess effect modification in the analysis.

Association of anemia with outcomes in men with moderate and severe chronic kidney disease

Anemia is a common complication of chronic kidney disease (CKD), but the outcomes associated with lower hemoglobin (Hgb) levels in patients with CKD not yet on dialysis are not well characterized. Analyses exploring outcomes associated with a single baseline Hgb value also do not account for the longitudinal variation of this measure. After collecting all Hgb measurements (N=17 194, median (range): 12 (1-168)) over a median follow-up period of 2.1 years in a historical prospective cohort of 853 male US veterans with CKD Stages 3-5 not yet on dialysis, we examined the association of time-averaged Hgb levels with predialysis all-cause mortality, end-stage renal disease (ESRD), and a composite end point of both. Kaplan-Meier survival analysis and Cox models adjusted for age, race, body mass index, smoking status, blood pressure, diabetes mellitus, cardiovascular disease, categories of estimated glomerular filtration rate, serum concentrations of albumin and cholesterol, and proteinuria were examined. Lower time-averaged Hgb was associated with significantly higher hazard of the composite end point (hazard ratio (95% confidence interval) in the adjusted model for time-averaged Hgb of <110, 111-120 and 121-130, compared to >130 g/l: 2.57 (1.85-3.58), 1.97 (1.45-2.66), 1.19 (0.86-1.63), P(trend)<0.001). Lower time-averaged Hgb was associated with both significantly higher pre-dialysis mortality and higher risk of ESRD, when analyzed separately. Anemia (especially time-averaged Hgb <120 g/l) is associated with both higher mortality and increased risk of ESRD in male patients with CKD not yet on dialysis.

The epidemiology and control of anaemia among pre-ESRD patients with chronic kidney disease

Anaemia is a common condition among pre-end-stage renal disease (pre-ESRD) patients with chronic kidney disease (CKD). Indeed, data from clinical studies indicate that anaemia may be present in as many as two-thirds of such patients. Use of recombinant human erythropoietin (EPO) provides an effective means of correcting anaemia in CKD patients and helps to reduce the risk of renal disease progression and related problems. Unfortunately, EPO therapy is underutilized in these persons. Consequently, anaemia remains a major problem in the pre-ESRD CKD population. Evidence suggests that anaemia in the presence of CKD can lead to an increased risk of a number of adverse outcomes, including mortality, progression of kidney disease, coronary heart disease, stroke, hospitalization, and decreases in quality of life. Anaemia's association with these adverse outcomes suggests that effective treatment of anaemia in pre-ESRD CKD patients is of great importance and that substantial efforts should be made to ensure that these patients receive appropriate therapy to correct anaemia.

Erythropoietin in Heart Failure

The incidence of both congestive heart failure (CHF) and end-stage renal disease both are increasing. Anemia is common in both conditions and is associated with a marked increase in mortality and morbidity in both CHF and chronic kidney insufficiency (CKI). Each of these 3 conditions can cause or worsen the other 2. In other words, a vicious circle frequently is present in which CHF can cause or worsen both anemia and CKI, in which CKI can cause or worsen both anemia and CHF, and in which anemia can cause or worsen both CHF and CKI. We have called this vicious circle the cardio renal anemia syndrome. Optimal treatment of CHF with all the recommended CHF medications at their recommended doses will, in our experience, frequently fail to improve the CHF and CKI if anemia is present and is not corrected. On the other hand, correction of the anemia with subcutaneous erythropoietin and intravenous iron has caused a great improvement in the CHF including a marked improvement in patient and cardiac function and a marked reduction in the need for hospitalization and for high-dose diuretics. It also frequently has caused renal function to improve or at least stabilize. In addition, patients' quality of life and exercise capacity also have improved with the correction of the anemia. In CKI patients, anemia also may play an important role in increasing the risk for death, coronary heart disease, stroke, and progression to end-stage renal disease. Erythropoietin may have a direct positive effect on the heart and brain unrelated to correction of the anemia by reducing cell apoptosis and by increasing neovascularization, both of which could prevent tissue damage. This could have profound therapeutic implications not only in CHF but in the future treatment of myocardial infarction, coronary heart disease, strokes, and renal failure.

Barriers to successful care for chronic kidney disease

Background

The National Kidney Foundation has formulated clinical practice guidelines for patients with chronic kidney disease (K/DOQI). However, little is know about how many patients actually achieve these goals in a dedicated clinic for chronic kidney disease.

Methods

We performed a cross-sectional analysis of 198 patients with an estimated glomerular filtration rate of less than 30 ml/min/1.73 m² and determined whether K/DOQI goals were met for calcium, phosphate, calcium-phosphate product, parathyroid hormone, albumin, bicarbonate, hemoglobin, lipids, and blood pressure.

Results

We found that only a small number of patients achieved K/DOQI targets. Recent referral to the nephrologist, failure to attend scheduled clinic appointments, African American ethnicity, diabetes, and advanced renal failure were significant predictors of low achievement of K/DOQI goals.

Conclusion

We conclude that raising awareness of chronic kidney disease and K/DOQI goals among primary care providers, early referral to a nephrologist, the exploration of socioeconomic barriers and cultural differences, and both patient and physician education are critical to improve CKD care in patients with Stage 4 and 5 CKD.

Dialyzer membrane permeability and survival in hemodialysis patients

BACKGROUND

We previously showed that nutritional protein concentrations were predictive of outcome, whereas variables reflecting body composition and dialysis dose were not, in a 30-month prospective follow-up of 1,610 hemodialysis patients. Information on dialysis membrane and erythropoietin use had to be evaluated in an additional follow-up.

METHODS

A subset of 650 patients from the initial cohort of 1,610 was analyzed for survival in a 2-year extension of follow-up. Detailed data were collected: demographics; cause of renal failure; time on dialysis therapy; type of membrane; erythropoietin treatment; body mass index (BMI); predialysis albumin, prealbumin, and bicarbonate levels; and outcome. Normalized protein catabolic rate (nPCR), dialysis adequacy, and lean body mass were computed from predialysis and postdialysis urea and creatinine values.

RESULTS

Patient characteristics were age of 61 +/- 16 years, 58% men, BMI of 22.7 +/- 4.4 kg/m2 , time on dialysis therapy of 102 +/- 73 months, and 8.8% had diabetes. Dialysis parameters were duration of 247 +/- 31 minutes, Kt/V of 1.4 +/- 0.3, and nPCR of 1.2 +/- 0.3 g/kg/d. Albumin level was 3.73 +/- 0.53 g/dL (37.3 +/- 5.3 g/L), and prealbumin level was 31 +/- 8 mg/dL. The survival rate was 78.7% after 2 years. Survival was influenced by age, presence of diabetes, use of high-flux membrane, and serum albumin level, but not other variables, including Kt/V and prealbumin level. Two-year variations in values for urea, creatinine, and weight were predictive of survival in univariate, but not multivariate, analyses.

CONCLUSION

In patients on dialysis therapy for a long period, better survival was observed when high-flux dialysis membranes were used.

A public health action plan is needed for chronic kidney disease

In 2005, chronic kidney disease (CKD) meets all criteria for classification as a public health problem in the United States. It imposes a large burden on society that is increasing despite ongoing efforts to control the disease. The burden is unevenly distributed by race and economic status, whereas evidence suggests that preventive strategies could substantially reduce the burden. Finally, there are indications that such strategies are not yet in place. A broad and coordinated public health approach to the burgeoning health, economic, and societal challenges of CKD is needed to complement present clinical approaches, increase awareness, promote early detection, and facilitate prevention and treatment.

General Medical Care among Patients with Chronic Kidney Disease: Opportunities for Improving Outcomes

Suboptimal health care during advancing chronic kidney disease (CKD) may result in greater morbidity and cost once dialysis is started and may preclude future transplantation. Medicare data were examined for the prevalence of selected general health, diabetes, and CKD interventions in a national cohort of patients in the 2 yr before dialysis initiation and compared with a contemporaneous non-CKD cohort. A total of 24,778 individuals who were aged > or =67 yr composed the CKD cohort, and 1,046,136 individuals who were aged > or =67 yr did not have CKD. Among patients with diabetes and CKD, fewer than two thirds had claims for eye examinations, 75% for HbA(1C) testing, and 68% for lipid testing, with similar proportions in the non-CKD cohort. Among those without diabetes, 47 and 54% of the CKD and non-CKD cohorts, respectively, had claims for lipid testing. Fewer than 50 and 15% had claims for influenza and pneumococcal vaccination, respectively, with slightly lower proportions among patients with CKD. Claims for cancer tests were found for 14 to 41% and 29 to 52% of individuals with and without CKD, respectively, depending on the type of cancer. A greater proportion of patients with diabetes tended to have claims for tests in both cohorts. In the CKD cohort, claims for anemia testing and parathyroid hormone levels were available in fewer than 50 and 15%, respectively, and claims for permanent vascular access were found for only 30% of hemodialysis patients. This study provides further evidence that patients with CKD may not be receiving general health and CKD care according to current recommendations.

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.

Complications of chronic kidney disease: anemia, mineral metabolism, and cardiovascular disease

This article focuses on the importance of three major complications of chronic kidney disease: (1) anemia, (2) calcium-phosphorus regulation and bone disease, and (3) cardiovascular risk profiling and treatment. The arguments for early and effective intervention have been amply made with respect to these three complications. Substantive trial data are sorely need to provide the definitive evidence that effective treatment of these complications results in better outcomes.