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

[TREAT or not to treat: anemia in type 2 diabetes and chronic kidney disease at stages 3 and 4]

Anemia is associated with an increased risk of cardiovascular and renal events among patients with type 2 diabetes and chronic kidney disease (CKD). Although erythropoiesis-stimulating agents (ESA) can effectively increase hemoglobin (Hb) levels, their effect on clinical outcomes has not been demonstrated in CKD patients. The TREAT study is the first randomized, double-blind, placebo-controlled trial with the aim to evaluate the effect of a Hb level of 13 g/dL on the risk of death, cardiovascular events and progression to end-stage renal disease (ESRD) in type 2 diabetes with stage 3 to 4 CKD. Four thousand and thirty-eight patients were included. Death, cardiovascular events and progression to ESRD were not different between the two groups. Stroke occurred in 101 patients assigned to DA and 53 patients assigned to placebo (p<0.001), and red-cell transfusions were administered in 14.8% patients in the DA group and in 24.5% patients assigned to placebo (p<0.001). There was a modest improvement in patient-reported fatigue in the DA group. Studies performed in CKD patients who were not undergoing dialysis failed to show a benefit of the use of ESA to target a Hb level of 13 g/dl or more, on the risk of death, cardiovascular morbidity and progression to ESRD. Post hoc analysis of randomized studies suggest that the increase cardiovascular risk induced by targeting a high Hb level is more related to the resistance state of patients who failed to increase their Hb level under high ESA doses and by the rate of change in Hb concentration over time. After the release of the TREAT study, the recommendations of a Hb level of 10 to 12 g/dl in CKD patients seems adequate. This target needs to be tailored for each patient taking into account the comorbidity, age and physical activity.

Mild anemia is frequent and associated with micro- and macroangiopathies in patients with type 2 diabetes mellitus

Aims/Introduction:  The present study investigated the frequency of mild anemia, which is not an indication of intensive therapy using drugs, in Japanese patients with type 2 diabetes mellitus and the association of mild anemia with diabetic complications.

MATERIALS AND METHODS

  This is a cross-sectional study of 1189 patients with type 2 diabetes mellitus. Anemia was defined as a hemoglobin level <13.5 g/dL in men and <12.0 g/dL in women. The patients with anemia were divided into two groups: (i) grade 1 anemia with a hemoglobin level ≥11.0 g/dL; and (ii) grade 2 anemia with a hemoglobin level <11.0 g/dL.

RESULTS

  The prevalence of anemia increased with the progression of the stage of diabetic nephropathy and chronic kidney disease. The frequencies of diabetic micro- and macroangiopathies increased with the progression of anemia among 798 patients without anemia, 300 with grade 1 anemia and 91 with grade 2 anemia. Both grade 1 and grade 2 anemia were associated with diabetic micro- and macroangiopathies. They remained independently associated with diabetic retinopathy, coronary heart disease and peripheral arterial disease after adjustment by age, sex, body mass index, use of angiotensin II receptor blocker, estimated glomerular filtration rate and stage of diabetic nephropathy.

CONCLUSIONS

  Mild anemia is frequent and associated with micro- and macroangiopathies in patients with type 2 diabetes mellitus. It is important to carry out intensive examinations for the detection of diabetic micro- and macroangiopathies in addition to evaluating the causes of anemia when mild anemia is found in patients with diabetes mellitus. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00060.x, 2010).

2008 Japanese Society for Dialysis Therapy: guidelines for renal anemia in chronic kidney disease

The Japanese Society for Dialysis Therapy (JSDT) guideline committee, chaired by Dr Y. Tsubakihara, presents the Japanese guidelines entitled "Guidelines for Renal Anemia in Chronic Kidney Disease." These guidelines replace the "2004 JSDT Guidelines for Renal Anemia in Chronic Hemodialysis Patients," and contain new, additional guidelines for peritoneal dialysis (PD), non-dialysis (ND), and pediatric chronic kidney disease (CKD) patients. Chapter 1 presents reference values for diagnosing anemia that are based on the most recent epidemiological data from the general Japanese population. In both men and women, hemoglobin (Hb) levels decrease along with an increase in age and the level for diagnosing anemia has been set at <13.5 g/dL in males and <11.5 g/dL in females. However, the guidelines explicitly state that the target Hb level in erythropoiesis stimulating agent (ESA) therapy is different to the anemia reference level. In addition, in defining renal anemia, the guidelines emphasize that the reduced production of erythropoietin (EPO) that is associated with renal disorders is the primary cause of renal anemia, and that renal anemia refers to a condition in which there is no increased production of EPO and serum EPO levels remain within the reference range for healthy individuals without anemia, irrespective of the glomerular filtration rate (GFR). In other words, renal anemia is clearly identified as an "endocrine disease." It is believed that defining renal anemia in this way will be extremely beneficial for ND patients exhibiting renal anemia despite having a high GFR. We have also emphasized that renal anemia may be treated not only with ESA therapy but also with appropriate iron supplementation and the improvement of anemia associated with chronic disease, which is associated with inflammation, and inadequate dialysis, another major cause of renal anemia. In Chapter 2, which discusses the target Hb levels in ESA therapy, the guidelines establish different target levels for hemodialysis (HD) patients than for PD and ND patients, for two reasons: (i) In Japanese HD patients, Hb levels following hemodialysis rise considerably above their previous levels because of ultrafiltration-induced hemoconcentration; and (ii) as noted in the 2004 guidelines, although 10 to 11 g/dL was optimal for long-term prognosis if the Hb level prior to the hemodialysis session in an HD patient had been established at the target level, it has been reported that, based on data accumulated on Japanese PD and ND patients, in patients without serious cardiovascular disease, higher levels have a cardiac or renal function protective effect, without any safety issues. Accordingly, the guidelines establish a target Hb level in PD and ND patients of 11 g/dL or more, and recommend 13 g/dL as the criterion for dose reduction/withdrawal. However, with the results of, for example, the CHOIR (Correction of Hemoglobin and Outcomes in Renal Insufficiency) study in mind, the guidelines establish an upper limit of 12 g/dL for patients with serious cardiovascular disease or patients for whom the attending physician determines high Hb levels would not be appropriate. Chapter 3 discusses the criteria for iron supplementation. The guidelines establish reference levels for iron supplementation in Japan that are lower than those established in the Western guidelines. This is because of concerns about long-term toxicity if the results of short-term studies conducted by Western manufacturers, in which an ESA cost-savings effect has been positioned as a primary endpoint, are too readily accepted. In other words, if the serum ferritin is <100 ng/mL and the transferrin saturation rate (TSAT) is <20%, then the criteria for iron supplementation will be met; if only one of these criteria is met, then iron supplementation should be considered unnecessary. Although there is a dearth of supporting evidence for these criteria, there are patients that have been surviving on hemodialysis in Japan for more than 40 years, and since there are approximately 20 000 patients who have been receiving hemodialysis for more than 20 years, which is a situation that is different from that in many other countries. As there are concerns about adverse reactions due to the overuse of iron preparations as well, we therefore adopted the expert opinion that evidence obtained from studies in which an ESA cost-savings effect had been positioned as the primary endpoint should not be accepted unquestioningly. In Chapter 4, which discusses ESA dosing regimens, and Chapter 5, which discusses poor response to ESAs, we gave priority to the usual doses that are listed in the package inserts of the ESAs that can be used in Japan. However, if the maximum dose of darbepoetin alfa that can currently be used in HD and PD patients were to be used, then the majority of poor responders would be rescued. Blood transfusions are discussed in Chapter 6. Blood transfusions are attributed to the difficulty of managing renal anemia not only in HD patients, but also in end-stage ND patients who respond poorly to ESAs. It is believed that the number of patients requiring transfusions could be reduced further if there were novel long-acting ESAs that could be used for ND patients. Chapter 7 discusses adverse reactions to ESA therapy. Of particular concern is the emergence and exacerbation of hypertension associated with rapid hematopoiesis due to ESA therapy. The treatment of renal anemia in pediatric CKD patients is discussed in Chapter 8; it is fundamentally the same as that in adults.

An economic evaluation of erythropoiesis-stimulating agents in CKD

BACKGROUND

The objective was to determine the cost-effectiveness of treating anemic patients with chronic kidney disease (CKD) with erythropoiesis-stimulating agents (ESAs) to a low (9-10.9 g/dL), intermediate (11-12 g/dL), or high (> 12 g/dL) hemoglobin level target compared with a strategy of managing anemia without ESAs.

STUDY DESIGN

Cost-utility analysis.

SETTING & PARTICIPANTS

Publicly funded health care system. Anemic patients with CKD, overall and stratified into dialysis-/non-dialysis-dependent subgroups.

MODEL, PERSPECTIVE, & TIMEFRAME

Decision analysis, health care payer, patient's lifetime.

MAIN OUTCOME

Cost per quality-adjusted life-year (QALY) gained.

RESULTS

For dialysis patients, compared with anemia management without ESAs, using ESAs to target a low hemoglobin level is associated with a cost per QALY of $96,270. Given a lack of direct trials comparing low and intermediate targets, significant uncertainty exists between these strategies. Treatment to a high hemoglobin target was always associated with worse clinical outcomes and higher costs compared with a low hemoglobin target. Results were similar in non-dialysis-dependent patients with CKD, with a cost per QALY for a low target compared with no ESA of $147,980.

LIMITATIONS

Given limitations in the available randomized controlled trials, we were able to model only 4 treatment strategies, balancing the need to consider relevant targets with the requirement for accurate estimates of clinical effect. We assumed that the efficacy of the different strategies would continue over a patient's lifetime.

CONCLUSIONS

Using ESAs to target a hemoglobin level > 12 g/dL is associated with worse clinical outcomes and significant additional cost compared with using ESAs to target lower hemoglobin levels (9-12 g/dL). Given a lack of studies comparing low (9-10.9 g/dL) and intermediate (11-12 g/dL) hemoglobin targets for clinical outcomes, including quality of life, the most cost-effective hemoglobin level target within the range of 9-12 g/dL is uncertain, although aiming for higher targets within this range will lead to higher costs.

Impact of haemoglobin and erythropoietin dose changes on mortality: a secondary analysis of results from a randomized anaemia management trial

BACKGROUND

Anaemia is a common complication of chronic kidney disease. A number of studies have identified an adverse association between haemoglobin (Hgb) variability and mortality. To date, no study has evaluated the impact of Hgb variability on mortality in the setting of a uniform Hgb target and erythropoiesis-stimulating agents (ESA) dosing strategy.

METHODS

One hundred and fifty-four haemodialysis (HD) patients from a previous randomized anaemia management study were followed up for up to 6 years. The impact of Hgb variability and ESA dosing parameters on subsequent mortality risk were evaluated.

RESULTS

More rapid rises in Hgb (Hgb deflect(pos)) and ESA dose increases were independently associated with mortality in multivariate analysis, whereas more rapid Hgb declines (Hgb deflect(neg)) and ESA dose decreases were not. Each gram per litre per week increase in Hgb deflect(pos) was associated with an adjusted hazard ratio (HR) of 1.23 (1.03-1.48), while for every 1000-unit increase in ESA dose, the adjusted HR was 1.12 (1.01-1.24). Factors associated with positive Hgb deflections included frequency and magnitude of ESA dose changes, baseline Hgb, patient weight and presence of an HD catheter.

CONCLUSIONS

Rapid Hgb rises and greater average Eprex dose increases were independently associated with a higher mortality risk in HD patients after adjustment for baseline Hgb and Eprex dose. A randomized controlled trial evaluating different ESA dosing strategies in response to individual patient ESA responsiveness is needed.

Health-related quality of life outcomes in chronic kidney disease

PURPOSE OF REVIEW

Patients with chronic kidney disease (CKD) endure compromised health-related quality of life (HRQOL). Although the link between HRQOL and increased mortality in patients with end-stage renal disease (ESRD) is well documented, less is known about the relationship between CKD and HRQOL. This article reviews the recent evidence on HRQOL, its correlates and proposed intervention strategies to improve HRQOL in CKD.

RECENT FINDINGS

A growing body of literature indicates that various comorbid conditions related to CKD play a substantial role in impaired HRQOL in CKD. Hypertension, both a cause and complication of CKD, negatively affects HRQOL due to associated comorbidities, side effects from antihypertensive medications and awareness of the diagnosis. Anemia has been associated with HRQOL, but concerns about the safety of erythropoietin-stimulating agents (ESAs) have led to more conservative anemia treatment. Frailty, symptom burden and depression are also major contributory factors to HRQOL in CKD.

SUMMARY

Certain determinants of HRQOL in CKD, namely anemia and depression, are treatable. Early identification and correction may improve overall well being of patients. Clinical trials are required to demonstrate whether treatment interventions benefit HRQOL in this high-risk population. Furthermore, whether integration of HRQOL assessment into routine clinical practice will improve HRQOL outcomes remains to be determined.

Characteristics of elderly patients with diabetes and end-stage renal disease

Because of a combination of demographic and social factors, such as the aging of the population in general, increased incidence of diabetes, and more liberal criteria for renal replacement therapy initiation, the proportion of the end-stage renal disease (ESRD) patients with diabetes who are considered elderly is currently the fastest growing segment of incident ESRD population. Despite the fast growth of this group, it is poorly characterized in current literature. In this review, we attempt to summarize the data available to date regarding demographic composition, outcomes, choice of renal replacement therapy, and other management issues including renal transplantation. There is significant evidence that the elderly diabetic patients might differ from the general dialysis population regarding renal replacement modality, vascular access for dialysis, and that guidelines addressing chronic kidney disease (CKD) issues such as nutrition and blood pressure may need modification in this ESRD subgroup. At the same time, other areas such as anemia and bone mineral metabolism have not been adequately studied. Lastly, despite lower rates of kidney transplantation in this population, it confers significant survival advantages, similar to that seen in younger populations. As the fastest growing group in the incident ESRD population, these patients have issues related to clinical management, which represent very important areas for future research.

Ethnic differences in anemia among patients with diabetes mellitus: the Diabetes Study of Northern California (DISTANCE)

To examine ethnic differences in hemoglobin testing practices and to test the hypothesis that ethnicity is an independent predictor of anemia among patients with diabetes mellitus. We conducted a panel study to assess the rate of hemoglobin testing during 1999-2001 and the period prevalence and incidence of anemia among 79,985 adults with diabetes mellitus receiving care within Kaiser Permanente of Northern California. Anemia was defined as hemoglobin <13.0 g/dL in men or < 12.0 g/dL in women. Overall, 82.1% of the cohort was tested for anemia at least once during the 3-year study period. Mixed ethnicity patients were most likely to be tested, followed by whites, blacks, Latinos, and Asians (P < 0.0001). Fifteen percent of the cohort had prevalent anemia at baseline, and an additional 22% of those tested developed anemia during the study period. Anemia was more prevalent among blacks and mixed ethnicity persons compared with other racial/ethnic groups. Anemia was also more prevalent among those >/=70 years of age or with estimated glomerular filtration rate <60 ml/min/1.73 m(2). In multivariable models, blacks had higher and Asians had lower odds of prevalent anemia and hazard ratios of incident anemia compared with whites. Within a large, diverse cohort with diabetes, ethnicity was predictive of anemia, even after adjustment for age, level of kidney function, and other potential confounders. Blacks with diabetes are at increased risk of anemia relative to whites. These differences may account for some of the observed ethnic disparities in diabetes complications.

[Anemia in chronic kidney disease and its cardiovascular implications]

Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD). Anemia is a common complication of CKD and it is an important independent risk factor for the development and progression of left ventricular hypertrophy (LVH) and heart failure. Anemia is also independently and synergistically associated with an enhanced risk of cardiovascular morbidity and mortality in CKD patients. The availability of erythropoiesis stimulating agents (ESA), such as recombinant human erythropoietin, has greatly improved the management of anemia in CKD patients. By increasing hemoglobin levels, ESA therapy has demonstrated to significantly improve quality of life and decrease morbidity and mortality among these patients. Earlier studies suggested that partial correction of anemia in CKD patients with LVH induced a partial regression of LV mass, while mainly uncontrolled and small-sized studies have suggested that anemia treatment with ESA in CKD patients with congestive heart failure improved NYHA class, cardiac function and reduced hospitalization rates. On the other hand, recent randomized controlled trials have reported no benefit of full anemia correction on LVH and no benefit, or even worse outcomes, in CKD patients versus partial anemia correction. Thus, recent anemia guidelines recommend target haemoglobin levels between 11-12 g/dl in CKD patients receiving ESA.

Left ventricular geometry predicts cardiovascular outcomes associated with anemia correction in CKD

Partial correction of anemia in patients with chronic kidney disease (CKD) reduces left ventricular hypertrophy (LVH), which is a risk factor for cardiovascular (CV) morbidity, but complete correction of anemia does not improve CV outcomes. Whether LV geometry associates with CV events in patients who are treated to different hemoglobin (Hb) targets is unknown. One of the larger trials to study the effects of complete correction of anemia in stages 3 to 4 CKD was the Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin Beta (CREATE) trial. Here, we analyzed echocardiographic data from CREATE to determine the prevalence, dynamics, and prognostic implications of abnormal LV geometry in patients who were treated to different Hb targets. The prevalence of LVH at baseline was 47%, with eccentric LVH more frequent than concentric. During the study, LVH prevalence and mean left ventricular mass index did not change significantly, but LV geometry fluctuated considerably within 2 yr in both groups. CV event-free survival was significantly worse in the presence of concentric LVH and eccentric LVH compared with the absence of LVH (P = 0.0009 and P < or = 0.0001, respectively). Treatment to the higher Hb target associated with reduced event-free survival in the subgroup with eccentric LVH at baseline (P = 0.034). In conclusion, LVH is common and associates with poor outcomes among patients with stages 3 to 4 CKD, although both progression and regression of abnormal LV geometry occur. Complete anemia correction may aggravate the adverse prognosis of eccentric LVH.

Use of agents stimulating erythropoiesis in digestive diseases

Anemia is the most common complication of inflammatory bowel disease (IBD). Control and inadequate treatment leads to a worse quality of life and increased morbidity and hospitalization. Blood loss, and to a lesser extent, malabsorption of iron are the main causes of iron deficiency in IBD. There is also a variable component of anemia related to chronic inflammation. The anemia of chronic renal failure has been treated for many years with recombinant human erythropoietin (rHuEPO), which significantly improves quality of life and survival. Subsequently, rHuEPO has been used progressively in other conditions that occur with anemia of chronic processes such as cancer, rheumatoid arthritis or IBD, and anemia associated with the treatment of hepatitis C virus. Erythropoietic agents complete the range of available therapeutic options for treatment of anemia associated with IBD, which begins by treating the basis of the inflammatory disease, along with intravenous iron therapy as first choice. In cases of resistance to treatment with iron, combined therapy with erythropoietic agents aims to achieve near-normal levels of hemoglobin/hematocrit (11-12 g/dL). New formulations of intravenous iron (iron carboxymaltose) and the new generation of erythropoietic agents (darbepoetin and continuous erythropoietin receptor activator) will allow better dosing with the same efficacy and safety.

Baseline characteristics in the Trial to Reduce Cardiovascular Events With Aranesp Therapy (TREAT)

BACKGROUND

Anemia augments the already high rates of fatal and major nonfatal cardiovascular and renal events in individuals with type 2 diabetes. In 2004, we initiated the Trial to Reduce Cardiovascular Events With Aranesp Therapy (TREAT). This report presents the baseline characteristics and therapies of TREAT participants and subgroups defined by the presence or absence of overt proteinuria and history of cardiovascular disease. The design of TREAT and baseline characteristics also are compared with 2 recent trials of nondialysis patients with chronic kidney disease (CKD) in which treatment with another erythropoiesis-stimulating agent targeting greater hemoglobin levels had either a neutral or adverse effect on clinical outcomes.

STUDY DESIGN

Randomized trial.

SETTING & PARTICIPANTS

4,044 participants with type 2 diabetes, CKD (defined as estimated glomerular filtration rate of 20 to 60 mL/min/1.73 m(2)), and anemia (hemoglobin < or = 11 g/dL) from 24 countries.

INTERVENTION

Darbepoetin alfa to attempt to increase hemoglobin levels to 13 g/dL compared with placebo.

OUTCOMES

TREAT is an event-driven design to continue until approximately 1,203 patients experience a primary event: the composite end point of death or cardiovascular morbidity (nonfatal myocardial infarction, congestive heart failure, stroke, or hospitalization for myocardial ischemia). The composite end point of death or need for long-term renal replacement therapy also is a primary end point.

CONCLUSIONS

With several-fold more patient-years and a placebo arm, TREAT will provide a robust estimate of the safety and efficacy of darbepoetin alfa and generate prospective data regarding the risks of major cardiovascular and renal events in a contemporarily managed cohort of patients with type 2 diabetes, CKD, and anemia.

Erythropoietin therapy and left ventricular mass index in CKD and ESRD patients: a meta-analysis

BACKGROUND AND OBJECTIVES

The purpose was to evaluate changes in the left ventricular mass index (LVMi) among anemic chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients treated with recombinant human erythropoietin (EPO).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A systematic review of the literature, reporting LVMi for patients before and after EPO therapy, was performed. The change in LVMi from baseline to the end of treatment was calculated and stratified by severity of anemia at baseline, target hemoglobin (Hb), and stage of kidney disease.

RESULTS

Fifteen eligible studies involving 1731 patients were identified. Cohorts with severe anemia at baseline (<10 g/dl), when given EPO using a lower target level (Hb <or= 12 g/dl or Hct <or= 36%) experienced significant reductions in LVMi (-32.7 g/m(2); 95% CI: -49.4 to -16.1, P < 0.05). However, these studies lacked control groups. Cohorts with moderate anemia at baseline showed insignificant changes in LVMi: 5.3 g/m(2) (95% CI: -0.8 to 11.3) for patients assigned to a lower target, and -6.6 g/m(2) (95% CI: -17.2 to 4.0) for patients assigned to a higher target (Hb > 12 g/dl or Hct > 36%). The effect size was similar in direction for both CKD and ESRD cohorts.

CONCLUSIONS

Aggregated results from multiple studies suggest that in severe anemia conventional Hb targets for EPO therapy are associated with a reduction in LVMi, but that in moderate anemia target Hb above 12 g/dl does not have a significant beneficial impact on LVMi compared with conventional targets.

Erythropoietic stress and anemia in diabetes mellitus

Anemia is one of the world's most common preventable conditions, yet it is often overlooked, especially in people with diabetes mellitus. Diabetes-related chronic hyperglycemia can lead to a hypoxic environment in the renal interstitium, which results in impaired production of erythropoietin by the peritubular fibroblasts and subsequent anemia. Anemia in patients with diabetes mellitus might contribute to the pathogenesis and progression of cardiovascular disease and aggravate diabetic nephropathy and retinopathy. Anemia occurs earlier in patients with diabetic renal disease than in nondiabetic individuals with chronic kidney disease. Although erythropoietin has been used to treat renal anemia for nearly two decades, debate persists over the optimal target hemoglobin level. Most guidelines recommend that hemoglobin levels be maintained between 105g/l and 125g/l. The suggested role of anemia correction--to prevent the progression of left ventricular hypertrophy in patients with diabetes mellitus--is yet to be established. However, an emphasis on regular screening for anemia, alongside that for other diabetes-related complications, might help to delay the progression of vascular complications in these patients.

Managing Anemia of Chronic Kidney Disease

Anemia begins early in the course of declining kidney function and is a frequent complication of chronic kidney disease. Both anemia and chronic kidney disease are underdiagnosed and undertreated. Anemia is associated with significantly increased risk of morbidity and mortality, including increased risks of left ventricular hypertrophy and heart failure. Although the detrimental effects of anemia are more common in patients with advanced chronic kidney disease, it has been suggested that correcting anemia in early stage kidney disease may improve health-related quality of life and also delay the progression to end-stage kidney disease. The identification of anemia in early stage chronic kidney disease and its aggressive management may also improve cardiovascular complications. Anemia of chronic kidney disease is predominantly a result of abnormal erythropoietin production and iron deficiency. Anemia may be the result of kidney failure itself, blood losses, nutritional deficiencies, and endocrine disorders. Guidelines and protocols for treating anemia can assist practitioners in identifying patients with anemia, treating anemia, evaluating response to treatment, and modifying treatment based on response. Erythropoeisis-stimulating agents have been shown to be effective in treating anemia in predialysis and dialysis patients. Iron supplementation is usually required in patients receiving erythropoeisis-stimulating agent therapy or with iron deficiency. Successfully managing anemia of chronic kidney disease with treatment strategies that accommodate patient lifestyle and improve compliance is paramount. Primary care physicians play an important role in the care of patients with kidney disease, as does collaboration with other medical professionals involved in their care.

What is so bad about a hemoglobin level of 12 to 13 g/dL for chronic kidney disease patients anyway?

Randomized controlled trials (RCTs) clearly indicate a possible cardiovascular morbidity and mortality risk when deliberately targeting a normal hemoglobin (Hb) concentration of 13 to 15 g/dL. By contrast, observational studies point to greater hospitalization and mortality at Hb levels <11 g/dL. There are no direct data to help us determine where, within this broad range, the optimal Hb lies. In RCTs and observational studies, significant confounding from the interrelationships of anemia and epoetin resistance occurs in patients with a serious illness. Patients with comorbidities such as malnutrition and inflammatory processes are more resistant to epoetin and, invariably, require greater cumulative epoetin doses. The effect of a higher erythropoiesis-stimulating agent (ESA) dose on increasing mortality has been noted repeatedly in post hoc analyses of RCTs. It is therefore too simplistic to solely attribute the outcomes achieved in RCTs to "target Hb." We discuss various mechanisms for potential harm at higher Hb levels as opposed to those that may be obtained from higher epoetin doses. For the individual patient, the therapeutic decision should center on what Hb is most appropriate at a "safe" ESA dose. Consequently, an Hb of 12 to 13 g/dL may be totally appropriate in some patient populations.

Chronic kidney disease, heart failure and anemia

The triad of chronic kidney disease, heart failure and anemia is well described and frequently encountered in clinical practice. While individually these disease states are associated with significant morbidity and mortality, the presence of the triad portends an even worse prognosis. Anemia is prevalent among cohorts of patients with chronic kidney disease and heart failure, indicating that its presence may serve as a central unifying hypothesis to explain poor outcomes in these populations. Observational and interventional trials of erythropoietin-stimulating agents, however, have had variable results on cardiovascular end points. Data are now emerging that suggest that treating erythropoietin deficiency in and of itself may be as or more important than the absolute levels of hemoglobin attained. Future research in this arena must focus on the optimal dose of erythropoietin administered to hemoglobin level achieved that will result in improved cardiovascular outcomes for patients with heart failure and kidney disease.

Nontraditional risk factors for cardiovascular disease in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) have a reduced lifespan, and a substantial proportion of these individuals die from cardiovascular disease. Although a large percentage of patients with CKD have traditional cardiac risk factors such as diabetes, hypertension and abnormalities in cholesterol, interventions to address these factors--which have significantly decreased cardiovascular mortality in the general population--have not shown such benefit in the CKD population. In addition, the severity and extent of cardiovascular complications in patients with CKD is disproportionate to the number and severity of traditional risk factors. This realization has focused attention on nontraditional cardiac risk factors that are particularly relevant to patients with CKD, including decreased hemoglobin levels, microalbuminuria, increased inflammation and oxidative stress, and abnormalities in bone and mineral metabolism. However, large prospective trials in patients with advanced CKD or in those requiring chronic dialysis have not shown that normalization of these nontraditional risk factors improves survival. Moreover, the mechanisms by which these nontraditional risk factors contribute to cardiovascular disease are unknown. Therefore, although current treatment of patients with CKD includes management of traditional and nontraditional risk factors, the value of modifying some nontraditional risk factors remains unclear.

Anaemia in diabetic renal failure: is there a role for early erythropoietin treatment in preventing cardiovascular mortality?

The mortality rate in diabetics with chronic kidney disease (CKD) is seven times higher than end-stage renal disease mainly because of cardiac causes. Anaemia may have a relevant role in the pathogenesis of cardiovascular (CV) disease in CKD. Anaemia occurs at an earlier stage of CKD in diabetic individuals than in those with other causes of CKD. Observational findings support the unfavourable influence of anaemia on mortality in CKD patients, and the combination of anaemia and CKD in diabetics identifies a group with a particularly high mortality risk. While the effect of erythropoietin on these patients' quality of life is known, its impact on mortality and CV risk is uncertain. The recent Anaemia Correction in Diabetes (ACORD) trial in diabetic CKD patients, which targeted haemoglobin levels of 13-15 mg/dl, disclosed no statistically significant favourable or adverse effects on mortality or morbidity over the 2-year follow-up, while other studies endeavouring to nearly normalize haemoglobin have reportedly proved risky. Even if anaemia is causally involved, the pathogenesis of CV disease in diabetics with CKD is so complex that addressing just one factor (anaemia) may not suffice to prevent CV risk, and normalizing haemoglobin levels may even be harmful.

Interpretation and review of health-related quality of life data in CKD patients receiving treatment for anemia

Recent evidence suggests that targeting higher hemoglobin values with erythropoiesis stimulating agents (ESAs) may lack mortality benefits and may even result in adverse cardiovascular complications when used in chronic kidney disease patients. However, ESAs are frequently reported to result in improvements in health-related quality of life (HRQOL). The purpose of this review is to evaluate the magnitude and nature of ESA-associated improvements in HRQOL, as well as to understand how to interpret the clinical significance of HRQOL data. HRQOL findings should be analyzed not by statistical significance but rather by using a minimal clinically important difference approach, or, alternatively, a distribution-based approach (such as Cohen's effect size). HRQOL domains that are most improved with ESAs relate to physical symptoms, vitality, energy, and performance; domains of social functioning and mental health show modest improvement, whereas the domains of emotional functioning and pain show very little improvement. Additional domains not measured by commonly used instruments (such as the SF-36) that have been shown to improve with ESAs include sleep, cognitive functioning, and sexual functioning. The maximal increase in HRQOL per incremental increase in hemoglobin appears to occur in the range of 10-12 g/dl. Beyond this range, additional normalization of hemoglobin (to 12-14 g/dl) results in continued (albeit blunted) improvements in HRQOL.

Health-related quality of life in the era of erythropoietin

Patients with end-stage renal disease treated with maintenance hemodialysis suffer substantial impairments in health-related quality of life (HRQOL). Despite widespread efforts, there are few interventions that improve the overall well-being and quality of life of this patient population. The current review provides a description of HRQOL as an essential, yet arguably overlooked health-related domain in hemodialysis patients, and discusses interventions that have been evaluated to improve the functional status and well-being of this population, with a particular focus on therapy with recombinant human erythropoietin. We review the controversy surrounding recombinant human erythropoietin as it relates to HRQOL, and describe the delicate balance faced by renal providers who seek to reduce hemodialysis patients' morbidity and mortality while simultaneously striving to improve patients' HRQOL.

The role of anemia management in improving outcomes for African-Americans with chronic kidney disease

Chronic kidney disease (CKD) is a serious threat to African-American public health. In this population CKD progresses to end-stage renal disease (ESRD) at quadruple the rate in Caucasians. Factors fueling progression to ESRD include diabetes and hypertension, which show high prevalences and accelerated renal damage in African- Americans, as well as possible nutritional, socioeconomic, and genetic factors. Anemia, a common and deleterious complication of CKD, is more prevalent and severe in African-American than Caucasian patients at each stage of the disease. Proactive management of diabetes, hypertension, anemia, and other complications throughout the course of CKD can prevent or delay disease progression and alleviate the burden of ESRD for the African-American community. Currently, African-Americans with CKD are less likely than Caucasian patients to receive anemia treatment before and after the onset of dialysis. Although African-Americans often require higher doses of erythropoiesis-stimulating agents, this may result from late treatment initiation, lower hemoglobin levels, or the presence of comorbidities such as diabetes and inflammation, although racial differences in response cannot be excluded. This review explores racial-specific challenges and potential solutions in renal anemia management to improve outcomes in African-American patients.

Treating elderly people with diabetes and stages 3 and 4 chronic kidney disease

Dedicated European and US clinical guidelines for type 2 diabetes in the elderly have been released, but they do not specifically address the issue of advanced chronic kidney disease (CKD) in older patients with diabetes. General clinical guidelines have been published on the treatment of patients with diabetic nephropathy (DN), but these address the issue of how to prevent progression and treat advanced DN without distinguishing between different age groups. Elderly patients with diabetes and stages 3 to 4 CKD have particular needs that differ from those of younger patients with the same conditions. This is mainly due to their frailty and shorter life expectancy. Differently tailored therapeutic strategies are needed, which may have less stringent targets; and the use of common drugs should be critically evaluated. The management agenda (metabolic control, low-protein diet, controlling BP, preventing progression of advanced DN, preventing cardiovascular outcomes) for these patients is discussed in light of the limits and perspectives of current guidelines. Intensive, simultaneous management of all items on the agenda may not be feasible for a proportion of older patients, and clinicians may have to give priority to reducing some risk factors rather than others, choosing between different therapies.

Hemoglobin levels and coronary artery disease

BACKGROUND

Anemia is a risk factor for adverse cardiovascular disease outcomes. However, there is limited information concerning the association of hemoglobin concentration and new onset of clinically recognized coronary artery disease (CAD).

METHODS

An historical cohort study was conducted with patients from Veterans Affairs medical centers. Baseline hemoglobin determinations were evaluated with respect to CAD using data from records of 25,622 subjects with no known heart disease. Coronary artery disease was identified from a new diagnosis based on the International Classification of Diseases, Ninth Edition, coding or a new prescription for nitroglycerin. Models were adjusted for age, sex, body mass index, smoking, systolic blood pressure, diastolic blood pressure, fasting glucose, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, creatinine clearance, and use of statin or beta-blocker.

RESULTS

Among the cohort, 5297 (20.7%) subjects developed CAD over 73,895 person-years of follow-up. Compared with control hemoglobin levels of 15.0 to 17.0 g/dL, the multivariable-adjusted risk of CAD increased with lower hemoglobin levels: an adjusted hazard ratio (HR) of 1.47 and 95% confidence interval (CI) of 1.18 to 1.84 for hemoglobin levels of 9.0 to 11.0 g/dL; an HR of 1.34 and 95% CI of 1.20 to 1.49 for 11.0 to 13.0 g/dL; and an HR of 1.07 and 95% CI of 1.01 to 1.13 for 13.0 to 15.0 g/dL. Hemoglobin levels > or = 17.0 g/dL were also associated with increased risk for CAD (adjusted HR 1.22, 95% CI 1.08-1.37).

CONCLUSIONS

Hemoglobin levels > or = 17 or < 15 g/dL are independently associated with increase risk for new cardiac events.

Blind Pew sends a black spot: the current haemoglobin controversy

Two randomised controlled trials of anaemia management published in the last year have fuelled the current haemoglobin controversy and led the United States Food and Drug Administration to issue a public health advisory warning concerning the use of erythropoiesis-stimulating agents and target haemoglobin levels. There is much more to the haemoglobin controversy than purely target haemoglobin levels. This article seeks to outline some of the current issues involved.

Anemia as a risk factor for chronic kidney disease

Chronic kidney disease (CKD) is an important and leading cause of end-stage renal disease (ESRD) and moreover, plays a role in the morbidity and mortality due to cardiovascular disease, infection, and cancer. Anemia develops during the early stages of CKD and is common in patients with ESRD. Anemia is an important cause of left ventricular hypertrophy and congestive heart failure. Correction of anemia by erthyropoiesis-stimulating agent (ESA) has been shown to improve survival in patients with congestive heart failure. Anemia is counted as one of the non-conventional risk factors associated with CKD. Hypoxia is one of the common mechanisms of CKD progression. Treatment by ESA is expected to improve quality of life, survival, and prevent the CKD progression. Several clinical studies have shown the beneficial effects of anemia correction on renal outcomes. However, recent prospective trials both in ESRD and in CKD stages 3 and 4 failed to confirm the beneficial effects of correcting anemia on survival. Similarly, treatment of other risk factors such as hyperlipidemia by statin showed no improvement in the survival of dialysis patients. Given the high prevalence of anemia in ESRD and untoward effects of anemia in CKD stages 3 and 4, appropriate and timely intervention on renal anemia using ESA is required for practicing nephrologists and others involved in the care of high-risk population. Lessons from the recent studies are to correct renal anemia (hemoglobin <10 g/dl not hemoglobin > or =13 g/dl). Early intervention for renal anemia is a part of the treatment option in the prevention clinic. In this study, clinical significance of anemia management in patients with CKD is discussed.

Erythropoiesis-stimulating agents: past and future

Renal anemia is a well-recognized complication of chronic kidney disease (CKD), and the deficiency of erythropoietin (EPO) is the primary cause. Observational population-based studies continue to demonstrate the association of low hemoglobin with adverse outcomes, and renal failure, cardiac failure, and anemia all may interact to cause or worsen each other, the so-called cardio-renal anemia syndrome. Treatment of anemia can be successfully achieved with the use of erythropoiesis-stimulating agents (ESAs). From a mechanistic point of view, however, the therapeutic benefits of ESA could be far beyond the correction of anemia. ESA modulates a broad array of cellular processes that include progenitor stem cell development, cellular integrity, and angiogenesis. A pleiotropic effect of EPO has been shown in the central nervous system, the cardiovascular system, and the kidney. While recent results of randomized controlled trials have established that there is little support for normalizing hemoglobin in CKD patients, the results of these studies do not negate renoprotective effects of EPO. A large number of patients with CKD will benefit from early recognition and appropriate correction of anemia with ESA.

Use of erythropoiesis-stimulating agents in patients with anemia of chronic kidney disease: overcoming the pharmacological and pharmacoeconomic limitations of existing therapies

Stage 3 chronic kidney disease (CKD), which is characterized by a glomerular filtration rate of 30 to 60 mL/min/1.73 m2 (reference range, 90-200 mL/min/1.73m2 for a 20-year-old, with a decrease of 4 mL/min per decade), affects approximately 8 million people in the United States. Anemia is common in patients with stage 3 CKD and, if not corrected, contributes to a poor quality of life. Erythropoiesis-stimulating agents (ESAs), introduced almost 2 decades ago, have replaced transfusions as first-line therapy for anemia. This review summarizes the current understanding of the role of ESAs in the primary care of patients with anemia of CKD and discusses pharmacological and pharmacoeconomic issues raised by recent data. Relevant studies in the English language were identified by searching the MEDLINE database (1987-2006). Two ESAs are currently available in the United States, epoetin alfa and darbepoetin alfa. More frequent dosing with epoetin alfa is recommended by the labeled administration guidelines because it has a shorter half-life than darbepoetin alfa. Clinical experience also supports extended dosing intervals for both these ESAs. Use of ESAs in the management of anemia of CKD is associated with improved quality of life, increased survival, and decreased progression of renal failure. Some evidence suggests that ESAs have a cardioprotective effect. However, correction of anemia to hemoglobin levels greater than 12 g/dL (to convert to g/L, multiply by 10) appears to increase the risk of adverse cardiac outcomes and progression of kidney disease in some patients. The prescription of ESAs in the primary care setting requires an understanding of the accepted use of these agents, the associated pharmacoeconomic challenges, and the potential risks. This review considers the need to balance effective ESA dosing intervals against the potential risks of treatment.

Mechanism of increased mortality risk with erythropoietin treatment to higher hemoglobin targets

Recent randomized, controlled trials indicate that there is a strong trend for increased risk for death or adverse composite outcomes with erythropoiesis-stimulating agent treatment in kidney disease to hemoglobin targets higher than those currently recommended. The failure of these trials to find a benefit of higher hemoglobin is in stark contrast to findings from large, observational, population-based studies that continue to demonstrate the association of low hemoglobin with adverse outcomes. The mechanisms for the adverse effect of higher hemoglobin targets that are seen in the randomized, controlled trials are poorly understood. This review explores hypotheses involving (1) the effect of achieved hemoglobin itself, (2) the role of erythropoiesis-stimulating agent treatment, (3) the use of iron supplementation, (4) increased blood pressure, and (5) erythropoiesis-stimulating agent hyporesponsiveness. Because the causal pathway has yet to be determined, further research is strongly encouraged. Clinical practice, however, should avoid erythropoiesis-stimulating agent treatment to higher hemoglobin targets, particularly in those with significant cardiovascular morbidity and those who require disproportionately high dosages of erythropoietin-stimulating agents to achieve recommended hemoglobin levels.

Cardiorenal anemia syndrome in chronic kidney disease

Anemia is a frequently encountered problem of chronic kidney disease (CKD) and deteriorates as renal function declines. Anemia increases the risk of death in CKD patients with diabetes and hypertension, which are the 2 leading causes of CKD. Recent studies suggest that correction of anemia improves patient quality of life and may delay the progression to end-stage renal disease. Anemia is often only treated in the late stages of CKD or after the initiation of renal replacement therapy. Thus, anemia of CKD is often unnoticed and lacks appropriate treatment. To practically manage high-risk patients with CKD and its associated cardiovascular diseases, it is mandatory to diagnose and appropriately treat anemia of CKD earlier. The optimal level of hemoglobin for greatest clinical benefit is unclear, but at present, it is recommended to remain > or = 11 g/dL. This paper provides recommendations for the diagnosis and management of anemia associated with CKD based on international practice guidelines.

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.