Hemoglobin variability does not predict mortality in European hemodialysis patients

Effects of Individualized Anemia Therapy on Hemoglobin Stability: A Randomized Controlled Pilot Trial in Patients on Hemodialysis

Key Points

Background

Anemia is common among patients on hemodialysis. Maintaining stable hemoglobin levels within predefined target levels can be challenging, particularly in patients with frequent hemoglobin fluctuations both above and below the desired targets. We conducted a multicenter, randomized controlled trial comparing our anemia therapy assistance software against a standard population-based anemia treatment protocol. We hypothesized that personalized dosing of erythropoiesis-stimulating agents (ESAs) improves hemoglobin target attainment.

Methods

Ninety-six patients undergoing hemodialysis and receiving methoxy polyethylene glycol-epoetin beta were randomized 1:1 to the intervention group (personalized ESA dose recommendations computed by the software) or the standard-of-care group for 26 weeks. The therapy assistance software combined a physiology-based mathematical model and a model predictive controller designed to stabilize hemoglobin levels within a tight target range (10–11 g/dl). The primary outcome measure was the percentage of hemoglobin measurements within the target. Secondary outcome measures included measures of hemoglobin variability and ESA utilization.

Results

The intervention group showed an improved median percentage of hemoglobin measurements within target at 47% (interquartile range, 39–58), with a 10% point median difference between the two groups (95% confidence interval, 3 to 16; P = 0.008). The odds ratio of being within the hemoglobin target in the standard-of-care group compared with the group receiving the personalized ESA recommendations was 0.68 (95% confidence interval, 0.51 to 0.92). The variability of hemoglobin levels decreased in the intervention group, with the percentage of patients experiencing fluctuating hemoglobin levels being 45% versus 82% in the standard-of-care group. ESA usage was reduced by approximately 25% in the intervention group.

Conclusions

Our results demonstrated an improved hemoglobin target attainment and variability by using personalized ESA recommendations using the physiology-based anemia therapy assistance software.

Clinical Trial registration number:

NCT04360902.

The Use of Anemia Control Model Is Associated with Improved Hemoglobin Target Achievement, Lower Rates of Inappropriate Erythropoietin Stimulating Agents, and Severe Anemia among Dialysis Patients

INTRODUCTION

The Anemia Control Model (ACM) is a certified medical device suggesting the optimal ESA and iron dosage for patients on hemodialysis. We sought to assess the effectiveness and safety of ACM in a large cohort of hemodialysis patients.

METHODS

This is a retrospective study of dialysis patients treated in NephroCare centers between June 1, 2013 and December 31, 2019. We compared patients treated according to ACM suggestions and patients treated in clinics where ACM was not activated. We stratified patients belonging to the reference group by historical target achievement rates in their referral centers (tier 1: <70%; tier 2: 70-80%; tier 3: >80%). Groups were matched by propensity score.

RESULTS

After matching, we obtained four groups with 85,512 patient-months each. ACM had 18% higher target achievement rate, 63% smaller inappropriate ESA administration rate, and 59% smaller severe anemia risk compared to Tier 1 centers (all p < 0.01). The corresponding risk ratios for ACM compared to Tier 2 centers were 1.08 (95% CI: 1.08-1.09), 0.49 (95% CI: 0.47-0.51), and 0.64 (95% CI: 0.61-0.68); for ACM compared to Tier 3 centers, 1.01 (95% CI: 1.01-1.02), 0.66 (95% CI: 0.63-0.69), and 0.94 (95% CI: 0.88-1.00), respectively. ACM was associated with statistically significant reductions in ESA dose administration.

CONCLUSION

ACM was associated with increased hemoglobin target achievement rate, decreased inappropriate ESA usage and a decreased incidence of severe anemia among patients treated according to ACM suggestion.

Infectious Risk and Variability of Hemoglobin Level in Patients Undergoing Hemodialysis

Introduction

In the management of anemia in chronic kidney disease, hemoglobin levels often fall below or exceed target ranges. Past retrospective cohort studies of patients undergoing hemodialysis with conventional erythropoiesis stimulating agents (ESAs) found that hemoglobin level fluctuations predicted mortality and cardiovascular adverse events; long-acting agents were thereafter widely available. An updated validation by a prospective cohort study was needed.

Methods

Using Cox regression models, we evaluated associations between hemoglobin variability and all-cause death, hospitalization, and cardiovascular, thrombotic, or infectious adverse event outcomes in 3063 hemodialysis patients' data from the Japanese Dialysis Outcomes and Practice Patterns Study (J-DOPPS) from 2012 to 2018.

Results

During a median follow-up time of 2.5 years, all-cause mortality was lowest in the first quartile and tended to be higher in groups with greater hemoglobin variability (hazard ratio [HR]: 95% confidence interval for the fourth quartile of an absolute value of hemoglobin variability: 1.44 [0.99-2.08], P for trend = 0.056). Infectious event incidence in these patients was also lower in the first quartile than for the other quartiles (P for trend < 0.01). The association was more pronounced in patients with lower serum ferritin levels or iron supplementation. Cardiovascular and thrombotic event incidence was not associated with hemoglobin variability.

Conclusions

Maintenance hemodialysis patients on ESA treatment with higher hemoglobin variability are at higher risk for all-cause mortality and particularly infectious events.

High hemoglobin fluctuation was a protective factor for cardiovascular-related death in peritoneal dialysis (PD) patients: A retrospective analysis of 232 patients with PD

Objectives

This study aimed to investigate the effect of hemoglobin (Hb) fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause deaths in peritoneal dialysis (PD).

Methods

According to the Hb fluctuation, patients were divided into low fluctuation group, moderate fluctuation group, and high fluctuation group, and then, the effects of Hb fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause death in PD were analyzed by regression analysis.

Results

A total of 232 patients were selected in this study. Compared with the low Hb fluctuation group, the moderate and high fluctuation groups had lower body mass index (BMI), estimated glomerular filtration rate (eGFR), and baseline Hb, and the moderate fluctuation group had less erythropoietin (EPO) and dialysis dose. Compared with survivors, patients with cardiovascular‐related and all‐cause deaths had lower mean Hb and Hb fluctuation (all p < 0.05). Cox regression analysis showed that before and after adjusting for confounding factors, Hb fluctuation was still independently correlated with cardiovascular prognosis, and higher Hb fluctuation was still a protective factor for cardiovascular‐related death in the Hb‐substandard group, but there was no significant correlation between Hb fluctuation and all‐cause death. Multivariate linear regression analysis revealed that Hb fluctuation was positively correlated with Kt/V and EPO dosage, but negatively correlated with the baseline Hb.

Conclusion

High Hb fluctuation was a protective factor for cardiovascular‐related death in PD with substandard Hb. Compared with Hb fluctuation, correction of anemia timely and making Hb reaches the standard level had a greater impact on reducing cardiovascular‐related death in PD.

Serum uric acid as a predictor of cardio- and cerebro-vascular diseases in maintenance hemodialysis patients

Background: Hyperuricemia is associated with an increased risk of cardio-and cerebrovascular disease (CVD) in general population. However, in the hemodialysis (HD) patients, low serum uric acid (SUA) increases the risk of mortality. Considering that CVD is the principal cause of death among maintenance HD patients, the present study aimed to determine the predictive value of SUA for CVD outcome in this population.

Methods: In this two-year follow-up prospective study, 205 outpatients under maintenance HD were enrolled from March 2017 to 2020. Patients’ demographic data, underlying diseases, and the results of serum tests, as well as two-year follow-up results of CVD events and mortality were recorded.

Results: A total of 130 (63%) patients were eligible for analysis; 62.9% were male; mean age of participants was 59±13years. At follow-up, coronary artery disease was observed in 43.2%, peripheral artery disease in 26.5%, and cerebrovascular disease in 20.5%; angiography was required in 52.3% and 4.5% died of CVD. SUA was ≤5.4 mg/dL in 52 patients, 5.5–6.1 mg/dL in 19, and ≥6.2 mg/dL in 59 patients with significant difference based on mean age, sex distribution, occurrence of cerebrovascular disease and cardiovascular mortality (P<0.05). Patients with cerebrovascular disease had a significantly lower SUA levels (P=0.006). Logistic regression showed the significant effect of SUA on the occurrence of cerebrovascular disease (P=0.008).

Conclusion: Low SUA can predict two-year incidence of cerebrovascular disease in HD patients. However, SUA levels did not show significant predictive effect on two-year coronary events, peripheral artery disease and cardiovascular mortality.

Effects of the route of erythropoietin administration on hemoglobin variability and cardiovascular events in hemodialysis patients

Introduction

Despite of the routine use of erythropoietin in hemodialysis patients to correct anemia, its administration route's effects on hemoglobin variability and cardiovascular events remain elusive. Herein, we determined different erythropoietin administration routes' effects on hemoglobin variability in hemodialysis patients and the associated factors of hemoglobin variability and cardiovascular events.

Methods

This is a post hoc analysis of a prospective, controlled, randomized, unblinded study with 78 Korean hemodialysis patients receiving intravenous (n = 40) or subcutaneous (n = 38) erythropoietin therapy. We evaluated hemoglobin variability by calculating the frequency of hemoglobin measurements outside the target range during all visits. The high-frequency group was defined by those with hemoglobin variability over the median value (25%) while the low-frequency group was defined by those with hemoglobin variability of <25%.

Results

In this analysis, 37 patients (51.1%) were males, and the mean age was 50.6 ± 12.5 years. The frequency of the value being outside the target hemoglobin range was higher in the subcutaneous group compared to the intravenous group (p = 0.03). The low-frequency group required significantly lower erythropoietin doses compared to the high-frequency group. In the adjusted Cox analysis, the parameter high group was a significant independent risk factor for cardiovascular events (p = 0.03).

Conclusion

The risk out of the target hemoglobin range increased with subcutaneous administration compared with intravenous erythropoietin administration in hemodialysis patients. An increased frequency of the value being outside the target hemoglobin range was also associated with an increased risk of cardiovascular events.

Low rather than high mean corpuscular volume is associated with mortality in Japanese patients under hemodialysis

Recent studies have reported that high mean corpuscular volume (MCV) might be associated with mortality in patients with advanced chronic kidney disease (CKD). However, the question of whether a high MCV confers a risk for mortality in Japanese patients remains unclear. We conducted a longitudinal analysis of a cohort of 8571 patients using data derived from the Japan Dialysis Outcomes and Practice Patterns Study (J-DOPPS) phases 1 to 5. Associations of all-cause mortality, vascular events, and hospitalization due to infection with baseline MCV were examined via Cox proportional hazard models. Non-linear relationships between MCV and these outcomes were examined using restricted cubic spline analyses. Associations between time-varying MCV and these outcomes were also examined as sensitivity analyses. Cox proportional hazard models showed a significant association of low MCV (< 90 fL), but not for high MCV (102 < fL), with a higher incidence of all-cause mortality and hospitalization due to infection compared with 94 ≤ MCV < 98 fL (reference). Cubic spline analysis indicated a graphically U-shaped association between baseline MCV and all-cause mortality (p for non-linearity p < 0.001). In conclusion, a low rather than high MCV might be associated with increased risk for all-cause mortality and hospitalization due to infection among Japanese patients on hemodialysis.

Time-averaged hemoglobin values, not hemoglobin cycling, have an impact on outcomes in pediatric dialysis patients

BACKGROUND

During erythropoietin-stimulating agent (ESA) treatment, hemoglobin (Hb) levels usually fluctuate; this phenomenon is known as "Hb cycling (HC)." In this study, we aimed to evaluate the predictors of HC and its impact on left ventricular hypertrophy (LVH) as a patient-important outcome parameter in pediatric dialysis patients.

METHODS

Records of patients followed up in nine pediatric nephrology centers between 2008 and 2013 were reviewed. More than 1 g/dL decrease or increase in Hb level was considered as HC. Patients were divided into two groups according to 12-month Hb trajectory as rare cycling (RC) (≤ 3) and frequent cycling (FC) (> 3 fluctuation) as well as three groups based on T-A-Hb levels: < 10, 10-11, and > 11 g/dL.

RESULTS

Two hundred forty-five dialysis (160 peritoneal dialysis (PD) and 85 hemodialysis (HD)) patients aged 12.3 ± 5.1 (range 0.5-21) years were enrolled in this study. Fifty-two percent of the patients had RC, 45% had FC, and only 3% had no cycling. There were no differences between HC groups with respect to age, dialysis modality, having anemia, hospitalization rate, residual urine volume, and mortality. Although left ventricular mass index (LVMI) tended to be higher in RC than FC group (65 ± 37 vs 52 ± 23 g/m^2.7, p = 0.056), prevalence of LVH was not different between the groups (p = 0.920). In regression analysis, FC was not a risk factor for LVH, but low T-A Hb level (< 10 g/dL) was a significant risk for LVH (OR = 0.414, 95% CI 0.177-0.966, p = 0.04). The target Hb levels were more often achieved in PD patients, and the number of deaths was significantly lower in non-anemic patients (Hb level > 11 g/dL).

CONCLUSION

Hb cycling is common among dialysis patients. Severity of anemia rather than its cycling has more significant impact on the prevalence of LVH and on inflammatory state.

Impact of hemoglobin variability on cardiovascular mortality in maintenance hemodialysis patients

PURPOSE

Although the association between anemia and cardiovascular mortality in hemodialysis patients is well established, whether hemoglobin variability (Hgb-Var) affects the prognosis remains unclear. We aimed to evaluate the association between Hgb-Var and cardiovascular mortality in Chinese hemodialysis patients.

METHODS

This retrospective study included 252 patients starting hemodialysis in Xin Hua Hospital between January 2009 and December 2015. Patients were divided into three tertiles based on Hgb-Var, as reflected by SD Hgb_mean, SD Hgb_range, and Hgb_deflection during a 12-month evaluation period after hemodialysis initiation. Left ventricular ejection fraction (EF) and left ventricular mass index (LVMI) were evaluated by echocardiography. Information on cardiovascular deaths occurred by December 2017 was collected. Multivariate Cox regression models were constructed to evaluate the association between Hgb-Var and cardiovascular mortality.

RESULTS

A total of 75 deaths and 52 cardiovascular deaths occurred during the 47-month follow-up (range 29.5-70). Under multivariate regression, the subgroup with the highest Hgb-Var had a higher risk of cardiovascular mortality after adjusting for relevant factors (HR vs. lowest SD Hgb_mean: 9.15, 95% CI 2.82, 29.693, P < 0.0001; HR vs. lowest SD Hgb_range: 3.81, 95% CI 1.40, 10.38, P = 0.005). Per 1 SD of Hgb_mean and Hgb_range elevations were both related to a 10% increase in the cardiovascular mortality risk. Baseline EF% and LVMI did not differ across the Hgb-Var subgroups. EF% upon the last patient visit to the clinic was lower in the subgroup with the highest SD Hgb_mean (P = 0.02).

CONCLUSIONS

High Hgb-Var is an independent risk factor for cardiovascular mortality in hemodialysis patients and might influence the cardiac function.

The anaemia control model: Does it help nephrologists in therapeutic decision-making in the management of anaemia?

INTRODUCTION

Anaemia is common in haemodialysis patients and treating it with erythropoiesis-stimulating agents (ESAs) is complex due to many factors.

OBJECTIVES

To assess the usefulness of the Anaemia Control Model (ACM) in the treatment of anaemia in haemodialysis.

METHODS

ACM is a software that predicts the optimal dose of darbepoetin and iron sucrose to achieve target haemoglobin (Hb) and ferritin levels, and makes prescription suggestions. Study conducted in dialysis clinics lasting 18months with two intervention phases (IPs) with ACM (IP1, n:213; IP2, n:218) separated by a control phase (CP, n:219). The primary outcome was the percentage of Hb in range and the median dose of ESAs, and the secondary outcomes were transfusion, hospitalisation and cardiovascular events. Clinical and patient analyses were performed. Hb variability was assessed by the standard deviation (SD) of the Hb. We also analysed the patients with most of the suggestions confirmed (ACM compliant group).

RESULTS

ACM increased the percentage of Hb in range: 80.9% in IP2, compared with 72.7% in the CP and reduced the intake of darbepoetin (IP1: 20 [70]; CP 30 [80] μg P=0.032) with less Hb fluctuation (0.91±0.49 in the CP to 0.82±0.37g/dl in IP2, P<0.05), improving in the ACM compliant group. The secondary outcomes decreased with the use of ACM.

CONCLUSIONS

ACM helps to obtain better anaemia results in haemodialysis patients, minimising the risks of treatment with ESAs and reducing costs.

Variability in hemoglobin levels in hemodialysis patients in the current era: a retrospective cohort study

Background: Given regulatory and reimbursement changes in anemia management, we examined hemoglobin variability in a contemporary cohort of maintenance hemodialysis patients. Materials and methods: The study population included > 200,000 hemodialysis patients with Medicare parts A and B as primary payer on October 1, 2012. Based on 25^th and 75^th percentiles, monthly hemoglobin values were categorized as low, intermediate, or high. Six variability categories were created by patterns during the 6-month observation period. Stable categories were: always-low, always-intermediate, always-high; variable patterns were: varying between low and intermediate, intermediate and high, low and high (most-variable). Cox proportional hazard models were used to assess the association between hemoglobin variability and all-cause mortality or major adverse cardiac events (MACE). Results: The 25^th and 75^th hemoglobin percentiles were 10.2 and 11.5 g/dL, respectively, in 2012, vs. 11 and 12.5 g/dL in 2004. ESA doses were lower in all categories in 2012 and transfusion rates higher, particularly for always-low patients. Hemoglobin variability decreased modestly: in 2004, 6.0% were always-intermediate, vs. 9.5% in 2012. In 2012, more patients were always-high and fewer were most-variable. Mortality hazard ratios (HRs) were higher for patients with any low hemoglobin: always-low (HR, 95% CI: 2.07, 1.84 – 2.31), varying between low and intermediate (1.37, 1.29 – 1.45), and most-variable (1.23, 1.16 – 1.31); the pattern was similar for MACE. Conclusions: In 2012 vs. 2004, hemoglobin levels decreased, the range of levels narrowed, and variability decreased modestly; transfusions increased. The highest risk of mortality and MACE appeared to occur in patients with persistently low, rather than highly variable, hemoglobin levels.


Factors Influencing Hemoglobin Variability and Its Association with Mortality in Hemodialysis Patients

Purpose

We aimed to investigate the factors influencing hemoglobin variability with inflammatory and nutritional parameters and its associations with all-cause mortality among hemodialysis patients.

Methods

One hundred and sixty-nine patients during the entire 12 months were enrolled into the study. Fasting plasma glucose, creatinine, calcium, phosphorus, alkaline phosphatase, parathyroid hormone (PTH), C-reactive protein (CRP), serum iron, serum iron-binding capacity, and transferrin saturation were analyzed. We defined six groups: low, target range, high, low-amplitude fluctuation with low hemoglobin levels, low-amplitude fluctuation with high hemoglobin levels, and high-amplitude fluctuation. Body mass index (BMI), malnutrition-inflammation score (MIS), and Charlson Comorbidity Index were evaluated.

Results

Hemoglobin variability was significantly correlated with age, platelet count, and number of hospitalization instances and inversely correlated with erythropoietin dose per body surface area. The coefficient of variation of hemoglobin showed a correlation with MIS and ferritin. The absolute level of hemoglobin showed a negative correlation between PTH, CRP, MIS, number of hospitalization instances and a positive correlation with albumin and BMI. High, low, and target-range groups showed survival advantage compared to the other three groups. In regression analysis, age, CRP levels, MIS, and BMI were the predictors of mortality.

Conclusion

Inflammation and duration of anemia were the major predictors of hemoglobin variability. High-amplitude fluctuation predicts high mortality; on the contrary low-amplitude fluctuations is related to better survival. MIS was independently associated with mortality. This trial is registered with NCT03454906.

Evaluating the effectiveness of IV iron dosing for anemia management in common clinical practice: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Background

Anemia management protocols in hemodialysis (HD) units differ conspicuously regarding optimal intravenous (IV) iron dosing; consequently, patients receive markedly different cumulative exposures to IV iron and erythropoiesis-stimulating agents (ESAs). Complementary to IV iron safety studies, our goal was to gain insight into optimal IV iron dosing by estimating the effects of IV iron doses on Hgb, TSAT, ferritin, and ESA dose in common clinical practice.

Methods

9,471 HD patients (11 countries, 2009-2011) in the DOPPS, a prospective cohort study, were analyzed. Associations of IV iron dose (3-month average, categorized as 0, <300, ≥300 mg/month) with 3-month change in Hgb, TSAT, ferritin, and ESA dose were evaluated using adjusted GEE models.

Results

Relative change: Monotonically positive associations between IV iron dose and Hgb, TSAT, and ferritin change, and inverse associations with ESA dose change, were observed across multiple strata of prior Hgb, TSAT, and ferritin levels. Absolute change: TSAT, ferritin, and ESA dose changes were nearest zero with IV iron <300 mg/month, rather than 0 mg/month or ≥300 mg/month by maintenance or replacement dosing. Findings were robust to numerous sensitivity analyses.

Conclusions

Though residual confounding cannot be ruled out in this observational study, findings suggest that IV iron dosing <300 mg/month, as commonly seen with maintenance dosing of 100-200 mg/month, may be a more effective approach to support Hgb than the higher IV iron doses (300-400 mg/month) often given in many European and North American hemodialysis clinics. Alongside studies supporting the safety of IV iron in 100-200 mg/month dose range, these findings help guide the rational dosing of IV iron in anemia management protocols for everyday hemodialysis practice.

Electronic supplementary material

The online version of this article (10.1186/s12882-017-0745-9) contains supplementary material, which is available to authorized users.

A threshold trajectory was revealed by isolating the effects of hemoglobin rate of rise in anemia of chronic kidney disease

BACKGROUND

To assess cardiovascular risk among various hemoglobin (Hb) rates of rise (RoR) in chronic kidney disease (CKD) patients with anemia who have initiated therapy with erythropoiesis stimulating agents (ESAs).

METHODS

Observational cohort of CKD patients initiating ESA therapy from the Centricity® database, 1990-2011. Proportional hazards models tested the hypothesis that a slower Hb RoR (0 < g/dl/month ⩽ 0.125) is associated with a lower cardiovascular (CV) incidence [composite of fatal/nonfatal myocardial infarction (MI) and stroke] compared with faster RoR (0.125 < g/dl/month ⩽ 2.0, and >2.0 g/dl/month).

RESULTS

A total of 9220 patients receiving ESAs were followed for an average of 3.1 years. Slow (group B) RoR versus medium (group C') and fast (group D') RoR in Hb, throughout all Hb milestones, was associated with lower risk of the composite endpoint [B (slow) versus D' (fast) [hazard ratio (HR) = 0.20 (0.11, 0.39), p < 0.0001]; B versus C' (medium) [HR = 0.34 (0.19, 0.62), p = 0.0004], and C' versus D' [HR = 0.60 (0.42, 0.85), p = 0.005]]. Within achieved Hb milestones, HRs were: B versus D' at milestone ⩾ 14.1 g/dl [HR = 0.17 (0.05, 0.56); p = 0.004] and at milestone 12.6-14.0 [HR = 0.18 (0.07, 0.46), p = 0.0004].

CONCLUSION

Rapid Hb rise is associated with adverse CV outcomes, with markedly lower risk for rates below a threshold trajectory of 0.125 g/dl/month, even with complete correction.

The relation between hemoglobin variability and carotid intima-media thickness in chronic hemodialysis patients

PURPOSE

Hemoglobin variability is a common problem among hemodialysis patients. We have previously demonstrated an association between Hb variability and left ventricular mass index. In this study, we investigated a possible relation between Hb variability and carotid intima-media thickness (CIMT).

METHODS

Twelve-month hemoglobin (Hb) values of 135 patients on maintenance hemodialysis were examined retrospectively. The range of 11-12 gr/dl was accepted as normal according to the KDOQI guidelines. Hemoglobin levels were classified as: Hb < 11 gr/dl:Low, Hb = 11-12 gr/dl:Normal and Hb > 12 gr/dl:High. According to 12-month Hb trajectory, the patients were divided into three groups: low-normal (LN), normal-high (NH) and low-high (LH). The CIMT measurements were taken on common carotid arteries bilaterally, and the average of these measurements were taken. The groups were compared in terms of CIMT measurements, demographic and laboratory features.

RESULTS

The LN, NH and LH groups were similar in terms of age, gender, incidence of diabetes mellitus, hypertension and cardiovascular diseases. Duration of hemodialysis, hemodialysis adequacy, serum lipids and CaxP products were also similar among the groups. The mean CIMT value was 0.601 ± 0.107, 0.744 ± 0.139 and 0.604 ± 0.134 mm in the LN, LH and NH groups, respectively (p < 0.001). CIMT was significantly higher in LH than in the other two groups.

CONCLUSIONS

In our study, when the three groups with similar risk factors for atherosclerosis were examined, we found that the LH group with the highest hemoglobin variability has the highest CIMT. This study is the first study to demonstrate that Hb variability is associated with an increase in CIMT in HD patients.

[The role of renal anemia and cardiovascular disease in the progression of chronic glomerulonephritis]

AIM

To study the rate of chronic glomerulonephritis progression when added by anemia and cardiovascular disease (CVD).

SUBJECTS AND METHODS

231 patients (133 men and 98 women) with predialysis chronic glomerulonephritis (CGN) were examined. The patients' mean age of was 35.8±11.8 years; the disease duration was 1 to 17 years. The disease onset was the date when urinalysis showed evidence of persistent proteinuria and (or) hematuria. Besides, the time when anemia developed and the clinical and instrumental signs of CVD appeared was taken as the initial reference point; the time when end-stage renal failure was diagnosed was taken to be the endpoint. Red blood cell counts with the inclusion of its indices, hemoglobin concentration, hematocrit values, daily proteinuria values, and glomerular filtration rate were analyzed. The biochemical parameters included the concentrations of electrolytes, creatinine, fibrinogen, iron, cholesterol, total protein and C-reactive protein (CRP). Electrocardiography and echocardiography, bicycle ergometry and 24-hour ECG monitoring were used to detect CVD.

RESULTS

The presence of anemia and CVD in patients with predialysis CGN versus those without anemia and CVD was associated with an increase in the concentrations of CRP [36.2 and 12.6%; respectively; (p<0.05)], creatinine [123.0 (83.2-217.0) and 86.5 (72.0-128.5) µmol/L; (p<0.05)] and a decrease in GFR [65.4 (30.8-95.5) and 92.7 (64.5-122.3) ml/min; (p<0.05)]. The 8-year survival of patients with CGN concurrent with CVD was noted to be 58% whereas the renal survival in patients with CGN + CVD + anemia was shorter and the 6-year survival in this case was as high as 52%.

CONCLUSION

Anemia and CVD in patients with CGN serve as additional independent factors for the progression of the underlying disease. The concurrence of CGN, anemia, and CVD substantially reduces the predialysis period.

Outcomes in patients with chronic kidney disease not on dialysis receiving extended dosing regimens of darbepoetin alfa: long-term results of the EXTEND observational cohort study

BACKGROUND

Extended dosing of the erythropoiesis-stimulating agent (ESA) darbepoetin alfa (DA) once biweekly or monthly reduces anaemia treatment burden. This observational study assessed outcomes and dosing patterns in patients with chronic kidney disease not on dialysis (CKD-NoD) commencing extended dosing of DA.

METHODS

Adult CKD-NoD patients starting extended dosing of DA in Europe or Australia in June 2006 or later were followed up until December 2012. Outcomes included haemoglobin (Hb) concentration, ESA dosing, mortality rates and receipt of dialysis and renal transplantation. Subgroup analyses were conducted for selected outcomes.

RESULTS

Of 6035 enrolled subjects, 5723 (94.8%) met analysis criteria; 1795 (29.7%) received dialysis and 238 (3.9%) underwent renal transplantation. Mean (standard deviation) Hb concentration at commencement of extended dosing was 11.0 (1.5) g/dL. Mean [95% confidence interval (CI)] Hb 12 months after commencement of extended dosing (primary outcome) was 11.6 g/dL (11.5, 11.6) overall and was similar across countries, with no differences between subjects previously treated with an ESA versus ESA-naïve subjects, subjects with versus without prior renal transplant or diabetics versus non-diabetics. Weekly ESA dose gradually decreased following commencement of extended DA dosing and was similar across subgroups. The decrease in weekly DA dose was accompanied by an increase in the proportion of patients receiving iron therapy. Hb concentrations declined following changes in ESA labels and treatment guidelines. The mortality rate (95% CI) was 7.06 (6.68, 7.46) deaths per 100 years of follow-up. Subjects alive at study end had stable Hb concentrations in the preceding year, while those who died had lower and declining Hb concentrations in their last year.

CONCLUSIONS

Long-term, extended dosing of DA maintained Hb concentrations in patients already treated with an ESA and corrected and maintained Hb in ESA-naïve patients.

Performance of a Predictive Model for Long-Term Hemoglobin Response to Darbepoetin and Iron Administration in a Large Cohort of Hemodialysis Patients

Anemia management, based on erythropoiesis stimulating agents (ESA) and iron supplementation, has become an increasingly challenging problem in hemodialysis patients. Maintaining hemodialysis patients within narrow hemoglobin targets, preventing cycling outside target, and reducing ESA dosing to prevent adverse outcomes requires considerable attention from caregivers. Anticipation of the long-term response (i.e. at 3 months) to the ESA/iron therapy would be of fundamental importance for planning a successful treatment strategy. To this end, we developed a predictive model designed to support decision-making regarding anemia management in hemodialysis (HD) patients treated in center. An Artificial Neural Network (ANN) algorithm for predicting hemoglobin concentrations three months into the future was developed and evaluated in a retrospective study on a sample population of 1558 HD patients treated with intravenous (IV) darbepoetin alfa, and IV iron (sucrose or gluconate). Model inputs were the last 90 days of patients’ medical history and the subsequent 90 days of darbepoetin/iron prescription. Our model was able to predict individual variation of hemoglobin concentration 3 months in the future with a Mean Absolute Error (MAE) of 0.75 g/dL. Error analysis showed a narrow Gaussian distribution centered in 0 g/dL; a root cause analysis identified intercurrent and/or unpredictable events associated with hospitalization, blood transfusion, and laboratory error or misreported hemoglobin values as the main reasons for large discrepancy between predicted versus observed hemoglobin values. Our ANN predictive model offers a simple and reliable tool applicable in daily clinical practice for predicting the long-term response to ESA/iron therapy of HD patients.

Benefits and risks of erythrocyte-stimulating agents

Chronic kidney disease (CKD) is a common and serious clinical problem. Anemia in patients with advanced CKD, frequently called renal anemia, causes disabling fatigue and diminishes patients’ quality of life. Frequent and excess transfusions or iron supplementation are potentially hazardous. Although it remains unclear whether the main factor in the development of renal anemia is the failure of erythropoietin (EPO) production in the kidney or a dysfunction in oxygen sensing exogenous EPO administration is considered a rational treatment. The advent of recombinant human erythropoietin (rHu-EPO) products has dramatically changed the therapeutic strategy for renal anemia. Although rHu-EPO therapy has improved patients’ quality of life and decreased the need for blood transfusions, some potential adverse effects have been reported till date. This brief review discusses the treatment of renal anemia with regard to the following: (1) historical background; (2) effectiveness of rHu-EPO; (3) some topics regarding the treatment of anemia, including EPO resistance, hemoglobin (Hb) cycling, and adequate Hb levels; (4) major adverse effects of rHu-EPO, including hypertension, thrombotic complications, and pure red cell aplasia; and (5) future problems to be resolved.

Preservation of anemia control and weekly ESA dosage after conversion from PEG-Epoetin beta to darbepoetin alfa in adult hemodialysis patients: the TRANSFORM study

Introduction

There is scant real-world information on switching treatment for anemia associated with chronic kidney disease (CKD) from methoxy polyethylene glycol-epoetin beta (PEG-Epo) to darbepoetin alfa (DA). TRANSFORM was a multi-center, observational study designed to describe the time course of hemoglobin (Hb) concentration (primary outcome measure) and other parameters of clinical management of anemia in European hemodialysis patients in clinical practice before and after a switch from PEG-Epo to DA.

Methods

Eligible subjects were adult patients with CKD dialyzed at European dialysis centers for ≥26 weeks and treated with PEG-Epo for ≥14 weeks immediately prior to being switched to DA and no earlier than January 2011. Erythropoiesis-stimulating agent doses and Hb values were recorded for the 14-week pre-switch and 26-week post-switch periods.

Results

Of the 1,027 eligible patients enrolled at 42 hemodialysis centers in 7 European countries, 785 were included in analyses. Mean (95% confidence interval [CI]) Hb was generally stable: 11.19 (11.11, 11.26), 11.48 (11.40, 11.57), and 11.29 (11.20, 11.37) g/dL at month −1 pre-switch and months 3 and 6 post-switch, respectively. The geometric mean (95% CI) PEG-Epo dose at month −1 was 27.4 (26.0, 28.8) µg/week; DA dose was 29.4 (27.9, 30.9), 23.3 (21.9, 24.9), and 25.6 (24.1, 27.1) µg/week at months 1, 4, and 6, respectively. The geometric mean (95% CI) dose ratio at switching was 1.06 (1.01, 1.11). When stratifying by dose-ratio categories <0.8, 0.8–1.2, and >1.2 at switching, mean DA dose and Hb converged within narrow ranges by month 6 post-switch: 23.9–27.0 µg/week and 11.1–11.5 g/dL, respectively. Hb excursions <10 g/dL were less frequent post-switch versus pre-switch.

Conclusion

Mean Hb values remained within a narrow range following switching from PEG-Epo to DA in this population of hemodialysis patients. Time trends of mean Hb and DA dose indicate that physicians titrated DA doses post-switch, to attain Hb concentrations comparable to those attained pre-switch with PEG-Epo.

Funding

Amgen (Europe) GmbH, Zug, Switzerland.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-014-0161-5) contains supplementary material, which is available to authorized users.

Effect of dialysis dose and membrane flux on hemoglobin cycling in hemodialysis patients

Many studies found that hemoglobin (Hb) fluctuation was closely related to the prognosis of the maintenance hemodialysis patients. We investigated the association of factors relating dialysis dose and dialyzer membrane with Hb levels. We undertook a randomized clinical trial in 140 patients undergoing thrice-weekly dialysis and assigned patients randomly to a standard or high dose of dialysis; Hb level was measured every month for 12 months. In the standard-dose group, the mean (±SD) urea reduction ratio was 65.1% ± 7.3%, the single-pool Kt/V was 1.26 ± 0.11, and the equilibrated Kt/V was 1.05 ± 0.09; in the high-dose group, the values were 73.5% ± 8.7%, 1.68 ± 0.15, and 1.47 ± 0.11, respectively. The standard deviation (SD) and residual SD (liner regression of Hb) values of Hb were significantly higher in the standard-dose group and low-flux group. The percentage achievement of target Hb in the high-dose dialysis group and high-flux dialyzer group was significantly higher than the standard-dose group and low-flux group, respectively. Patients undergoing hemodialysis thrice weekly appear to have benefit from a higher dialysis dose than that recommended by current KDQQI (Kidney Disease Qutcome Quality Initiative) guidelines or from the use of a high-flux membrane, which is in favor of maintaining stable Hb levels.

Does erythropoietin cause hemoglobin variability--is it 'normal'?

Hemoglobin variability (Hb-var) in patients with chronic kidney disease has been stipulated to be a result of exogenous treatment with erythropoiesis stimulating agents (ESA) and has been related to mortality in dialysis patients. We hypothesized the existence of Hb-var independent of ESA administration and compared it to that in healthy adults using data from the Scripps-Kaiser and NHANES III databases. We studied the Hb-var in 1571 peritoneal dialysis patients which included 116 patients not requiring treatment with erythropoietin. We systematically studied the differences between the groups that needed ESA therapy and those who did not. White race and male sex were significant predictors of need for erythropoietin therapy. We found peritoneal dialysis patients to exhibit significantly increased Hb-var independent of treatment with exogenous erythropoietin (0.99 gm/dL vs. 1.17 gm/dL, p-value<0.001). We found age to be a significant determinant of Hb-var in the ESA treated group. Hb-var in younger patients (<30 years) was increased by 50% compared to young healthy adults. The Hb-var in elderly (>60 years) peritoneal dialysis patients was similar to that seen in healthy elders, suggesting similarity with anemia of aging. We conclude that exogenous ESA administration does not explain Hb-var entirely but may enhance it. Intrinsic factors affecting erythropoiesis including age may be the major determinants of Hb-var.

Determinants of hemoglobin variability in stable peritoneal dialysis patients

PURPOSE

Significant within-patient hemoglobin (Hb) level variability is well recognized in particularly hemodialysis patients. Several factors such as hospitalizations, intercurrent diseases and IV iron therapy are found to be related to Hb variability (Hb-var). In this observational study, we aimed to identify predictors and outcome of Hb-var in peritoneal dialysis (PD) patients without hospitalization, intercurrent disease and IV iron therapy during the study period.

METHODS

All patients were in the maintenance phase of short-acting erythropoiesis-stimulating agents (ESAs) therapy. The target range of Hb was 11-12 g/dL according to KDOQI Guidelines in 2007. The desired range of Hb was 11-12.5 g/dL. Patients' demographic and laboratory data were collected at baseline. Atherosclerotic disease was assessed using carotid intima-media thickness (CIMT). We assessed Hb variability with various methods using SD Hbmean, SD Hbrange and the velocity of Hb change. Hb deflectpositive, Hb deflectnegative, Hb values and ESA dosing were recorded monthly for 6 months.

RESULTS

This study included 50 prevalent PD patients (mean age 46.9 ± 13.7 years, 25 women). The mean velocity of Hb change was negatively correlated with age and positively correlated with frequent ESA dose changes. Higher albumin and residual renal function (RRF) were also positively correlated with Hb deflectpositive. Patients with CIMT ≥0.7 cm had lower SD Hb range compared to CIMT <0.7 cm. Cumulative survival was better in patients with Hb levels consistently ≥10 g/dL compared to patients who had Hb <10 g/dL for at least 1 month. However, Hb-var was not associated with mortality.

CONCLUSIONS

In PD patients without hospitalization, intercurrent disease(s) or IV iron therapy, young age, higher albumin or RRF and lower CIMT were associated with greater oscillations in response to ESA therapy. Careful and appropriate ESA dose changes considering these parameters could minimize Hb variability in these patients.

Effect of hemoglobin variability on mortality and some cardiovascular parameters in hemodialysis patients

BACKGROUND AND OBJECTIVES

Most hemodialysis patients show hemoglobin fluctuations between low-normal and high levels. This hemoglobin variability may cause left ventricle hypertrophy and may increase mortality as well. Recently, many studies were designed to evaluate the effect of hemoglobin variability on mortality but results were conflicting. We aimed to investigate the effect of hemoglobin variability on mortality and some cardiovascular parameters in hemodialysis population.

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Hundred and seventy-five prevalent hemodialysis patients classified into three hemoglobin variability groups according to their hemoglobin levels throughout 24 month observation period: Low-Normal, Low-High, Normal-High. Groups were compared in terms of laboratory, demographical data and mortality rates, initial and the end of 24 month echocardiographic data. Initial and last echocardiographic data were compared within groups in terms of left ventricle mass index increase.

RESULTS

Mortality rates and cardiovascular risk factors such as coronary heart disease, diabetes mellitus and hypertension that may affect mortality were same between three groups. There was no significant difference between three groups in terms of echocardiographic and laboratory parameters. Only Low-High group showed significant increase on left ventricle mass index when initial and last echocardiographic parameters were compared.

CONCLUSIONS

Consistent with previous studies, we found that most of the patients exhibited hemoglobin variability and our study is consistent with some of the studies that did not find any relationship between hemoglobin variability and mortality. Firstly, in this study based on objective data, it was shown that hemoglobin variability has adverse effect on left ventricle geometry independent from anemia.

Low hemoglobin levels and hypo-responsiveness to erythropoiesis-stimulating agent associated with poor survival in incident Japanese hemodialysis patients

Although erythropoiesis-stimulating agents (ESAs) are effective at treating anemia, the association between hemoglobin (Hb) levels and survival is still unclear, especially for the incident Japanese hemodialysis (HD) population. The Japan Erythropoietin Treatment (JET) Study is an open multi-center, prospective, observational study designed to evaluate the relationship between the maintenance of Hb levels and new HD patient prognosis after the first administration of epoetin beta. Landmark analyses were performed to examine the relationship between Hb levels at 6 months and survival. Among a total of 10,310 patients, 6631 completed the initial 6 months of epoetin beta treatment (induction phase) and were followed up for a further 2.5 years (maintenance phase). Three-year survival rate of patients with <9 g/dL Hb levels after 6 months was 74.1%, which was significantly lower than 89.3% for patients with Hb levels 10 to 11 g/dL; the adjusted hazard ratio (HR) was 2.08 (95% CI, 1.57-2.77; P < 0.0001). Moreover, the 3-year survival rate for poor responders defined by Hb levels <10 g/dL and weekly epoetin beta doses ≥ 9000 IU during the induction phase was 71.6%, which was significantly lower than 89.4% for the group, which had Hb levels 10 to 11 g/dL excluding poor responders and those with excursion; the HR was 1.71 (95% CI, 1.13-2.60; P = 0.0118). Adverse events related to the treatment were reported in 71 of 10,310 patients (0.69%). These findings suggest that the achieved low Hb levels and poor response to ESA therapy are significantly associated with high mortality.

Renal anemia control in Lithuania: influence of local conditions and local guidelines

Erythropoietin stimulating agents had a long haul in Lithuania—we had no epoetin till 1994 and there was no intravenous iron in 2001–2004. The aim of this study was to assess the changes of renal anemia control in hemodialysis patients from early independence of Lithuania till nowadays and to evaluate the link of anemia with hospitalization rates and survival and hemoglobin variability in association with mortality. In December of each year since 1996 all hemodialysis centers have been visited and data has been collected using special questionnaires. The history of renal anemia control in Lithuania was complicated; however, a significant improvement was achieved: 54.7% of hemodialysis patients reached the target hemoglobin; all patients have a possibility of treatment with epoetin and intravenous iron. The involuntary experiment with an intravenous iron occurred in Lithuania because of economic reasons and confirmed the significant role of intravenous iron in the management of renal anemia. Hemoglobin below 100 g/L was associated with a 2.5-fold increase in relative risk of death and 1.7-fold increase in relative risk of hospitalization in Lithuanian hemodialysis patients. Although hemoglobin variability was common in Lithuanian hemodialysis patients, we did not find the association between hemoglobin variability and all-cause mortality in our study.

Stable hemoglobin in hemodialysis patients: forest for the trees--a 12-week pilot observational study

Background

Hemoglobin (Hb) variability is a common occurrence in hemodialysis patients treated with erythropoiesis-stimulating agents. High amplitude fluctuations have been associated with greater risk of morbidity and mortality.

Methods

This prospective, single centre pilot observational study was conducted over a 3-month period in daily practice patterns, to assess per-dialysis events and inter-dialysis complications that could interfere with erythropoiesis in patients undergoing hemodialysis.

Results

Mean Hb levels remained stable in the 78 evaluable patients, as did darbepoetin alfa (DA) doses, including in patients suffering from diabetes or cardiac affections. In total, an average of 7.7 events / patient / month occurred, but no significant relationship with Hb excursions was shown.

Conclusion

The observation of 7.7 events per patient per month suggests a careful monitoring of Hb and DA dosing every other week, in order to maintain Hb level within the target.

Between subjects variability in haemoglobin and dose are not associated with the erythropoiesis-stimulating agent used to treat anaemia in dialysis: a meta-analysis

AIMS

We aimed to compare mean and between subject variability in haemoglobin (Hb) and erythropoiesis-stimulating agents (ESA) dose across the ESA compounds used to treat anaemia in dialysis patients.

METHODS

We performed a meta-analysis of randomized trials evaluating ESA in adult patients with chronic kidney disease on dialysis (target Hb 9-13.5 g dl(-1)), and compared mean Hb and its standard deviation (SD), and ESA dose and its coefficient of variation (CV) between the different agents [rHuEPO alfa or beta, darbepoetin alfa, pegylated-epoetin beta (PEG-EPO) or other epoetins]. The effect of route and frequency of administration, frequency of dose adjustments, study blinding and type, baseline value, Hb target and sampling frequency were also assessed.

RESULTS

Among 4983 patients from 16 studies, pooled Hb mean and SD during the evaluation phase were 11.5 g dl(-1) (95% CI 11.3, 11.7) and 0.99 g dl(-1) (0.88, 1.09), respectively. The Hb mean and SD were not significantly influenced by the covariates tested. Only Hb SD was significantly lower in maintenance studies relative to correction studies. No differences in mean ESA dose and CV were found across the covariates, except that PEG-EPO monthly dose was 42% higher than the every 2 weeks dose and the rHuEPO i.v. dose was 32% higher than the s.c. dose.

CONCLUSIONS

Between subject variability in haemoglobin and ESA dose in dialysis patients is not associated with the type of ESA, nor with the dosing interval or route of administration, except for higher dose requirements in PEG-EPO monthly administration relative to every 2 weeks or rHuEPO i.v. relative to s.c.

Hospitalization and mortality in hemodialysis patients: association with hemoglobin variability

BACKGROUND/AIMS

Hemodialysis patients show complications associated with low or high hemoglobin (Hb), which occur frequently in clinical practice. We sought to determine the clinical importance of these changes in Hb levels.

METHODS

From our clinic cohorts, we identified 1,634 who met inclusion criteria for analysis of hospitalization frequency and 1,953 analysis of mortality; many patients were in both groups. Hb excursions outside the target range (11-12.5 g/dl) were studied in relation to patient outcomes.

RESULTS

Hb measures below range were associated with more frequent hospitalization (p < 0.001), increased length of stay (p < 0.001), and increased mortality (p < 0.01), whereas Hb above range was associated with a reduced frequency of hospitalization (p < 0.01) and shorter length of stay (p < 0.01), and tended to be associated with reduced mortality.

CONCLUSIONS

Excursions below range were associated with negative outcomes, but excursions above range were either beneficial or neutral. Our findings indicate that clinicians should focus on low Hb as a negative indicator of patient status, whereas transient Hb above range is a marker for patient health and well-being.

Anaemia management and mortality risk in chronic kidney disease

Renal anaemia is a frequent complication in patients with chronic kidney disease (CKD). Severe anaemia (haemoglobin <90 g/l) is associated with increased risks of mortality and cardiac complications, such as left ventricular hypertrophy and cardiovascular disease, and impaired quality of life. Randomized controlled trials have tested the hypothesis that increasing haemoglobin level using erythropoiesis-stimulating agents (ESAs) lowers these risks and improves quality of life. Use of ESAs to normalize haemoglobin levels (to ≥130 g/l) versus the partial correction of anaemia (to haemoglobin levels of 90-110 g/l) has repeatedly been shown to have no cardiac benefit and to be associated with no incremental improvement in outcomes and quality of life (except fatigue), but has been shown to be associated with an increased risk of cardiovascular events and death. Use of more-intense iron dosing has been proposed in order to reduce ESA dosing but liberal intravenous iron therapy is also associated with complications, and its long-term safety has not yet been adequately investigated. For patients with CKD on dialysis, US medication labels recommend administering ESAs at doses sufficient to avoid transfusions, whereas European and Canadian labels recommend targeting haemoglobin levels of 100-120 g/l and 110-120 g/l, respectively. Treatment of anaemia to haemoglobin levels of 90-110 g/l in patients with CKD accomplishes what we want--a reduced need for transfusions and possible reductions in fatigue, while avoiding high doses of ESA or iron in order to achieve a specific haemoglobin goal.

The MAINTAIN study--managing hemoglobin variability with darbepoetin alfa in dialysis patients experiencing a severe drop in hemoglobin

BACKGROUND

Dialysis patients, receiving erythropoiesis stimulating agents, typically show signs of hemoglobin variability as a consequence of their dosing patterns, bleeding, infection, etc., which is commonly managed adjusting the dose regimen of the erythropoiesis stimulating agent. However, information on dosing strategies used in daily clinical practice and their outcomes in relation to hemoglobin variability is limited.

OBJECTIVES

To investigate clinical practice in Austria in relation with the management of hemoglobin variability, defined as a decrease of ³ 1 g/dL within 4 weeks from ³ 11 g/dL to £ 11 g/dL during maintenance therapy with darbepoetin alfa. The nature and incidence of clinical events related to the hemoglobin drop were also assessed.

RESEARCH DESIGN AND METHODS

The MAINTAIN non-interventional study was conducted in hemodialysis patients, receiving darbepoetin alfa in accordance to the label approved in the European Union at that time. Patient data were documented retrospectively for the 3 months prior to the hemoglobin drop. Data for the 6 months post hemoglobin drop were collected retrospectively or prospectively, depending on the time of patient inclusion respective to the Hb drop.

RESULTS

A hundred thirty six of 154 patients fulfilled all inclusion/exclusion criteria and had prospective documentation of 6 months. The main causes for the hemoglobin drop included surgical and medical procedures (36.1 %), and infections or infestations (24.4 %). The median treatment period was 273 days. The mean hemoglobin drop was - 1.74 g/dL (95 % confidence interval (CI): - 1.60 to - 1.87). Consequently, 81 % of the patients had their dose of darbepoetin alfa increased within a median Kaplan-Meier time to dose increase of 12.5 days (95 % CI: 6-22). The geometric mean weekly darbepoetin alfa dose increased by a factor of 1.1 from 29.1 mg (95 % CI: 24.6-34.4) in the 3 months before hemoglobin drop to 32.4 (95 % CI: 27.2-38.6) in months 4-6 post hemoglobin drop. Three patients had red blood cell transfusions before hemoglobin drop and nine patients after hemoglobin drop. The mean hemoglobin increase was 0.43 g/dL (95 % CI: 0.24-0.62) from immediately prior to 2 weeks after dose increase. The median Kaplan-Meier time to achieve a hemoglobin ³ 11 g/dL after hemoglobin drop was 36 days (95 % CI: 32-45). Frequent darbepoetin alfa dose adjustments were necessary to sustain maintenance levels. No drug-related adverse events were reported.

CONCLUSIONS

This observational study describes physicians' reactions to a drop in hemoglobin in clinical practice. Using darbepoetin alfa, the drop was generally compensated without leading to overcorrection.

Lack of adequate predialyis care and previous hemodialysis, but not hemoglobin variability, are independent predictors of anemia-associated mortality in incident Brazilian peritoneal dialysis patients: results from the BRAZPD study

BACKGROUND/AIMS

The objective of this study was to analyze the prevalence of anemia and variability of hemoglobin (Hb) values in peritoneal dialysis (PD) patients, to establish its associated factors and their impact on clinical outcomes in a large cohort of patients starting PD treatment.

METHODS

Data were collected monthly in incident patients, who were followed until the primary endpoint (death from all causes) or until leaving the study.

RESULTS

2,156 patients starting PD were included. The prevalence of Hb lower than 11 g/dl was 57% at baseline and decreased to 38% at the 4th month. Lack of adequate predialysis care and previous treatment with hemodialysis were the most important factors associated with anemia. Anemia was an independent predictor of mortality. There were no differences in patient survival throughout the different groups of Hb variability.

CONCLUSION

Our data point to the need of identifying other risk factors for anemia and aggressively interfere with the modifiable ones in order to correct anemia and decrease mortality in this group of high-risk patients.

Impact of mineral and bone disorder on healthcare resource use and associated costs in the European Fresenius medical care dialysis population: a retrospective cohort study

Background

Secondary hyperparathyroidism (SHPT) is associated with mortality in patients with chronic kidney disease (CKD), but the economic consequences of SHPT have not been adequately studied in the European population. We assessed the relationship between SHPT parameters (intact parathyroid hormone [iPTH], calcium, and phosphate) and hospitalisations, medication use, and associated costs among CKD patients in Europe.

Methods

The analysis of this retrospective cohort study used records of randomly selected patients who underwent haemodialysis between January 1, 2005 and December 31, 2006 at participating European Fresenius Medical Care facilities in 10 countries. Patients had ≥ 1 iPTH value recorded, and ≥ 1 month of follow-up after a 3-month baseline period during which SHPT parameters were assessed. Time at risk was post-baseline until death, successful renal transplantation, loss to follow-up, or the end of follow-up. Outcomes included cost per patient-month, rates of hospitalisations (cardiovascular disease [CVD], fractures, and parathyroidectomy [PTX]), and use of SHPT-, diabetes-, and CVD-related medications. National costs were applied to hospitalisations and medication use. Generalised linear models compared costs across strata of iPTH, total calcium, and phosphate, adjusting for baseline covariates.

Results

There were 6369 patients included in the analysis. Mean ± SD person-time at risk was 13.1 ± 6.4 months. Patients with iPTH > 600 pg/mL had a higher hospitalisation rate than those with lower iPTH. Hospitalisation rates varied little across calcium and phosphate levels. SHPT-related medication use varied with iPTH, calcium, and phosphate. After adjusting for demographic and clinical variables, patients with baseline iPTH > 600 pg/mL had 41% (95% CI: 25%, 59%) higher monthly total healthcare costs compared with those with iPTH in the K/DOQI target range (150–300 pg/mL). Patients with baseline phosphate and total calcium levels above target ranges (1.13–1.78 mmol/L and 2.10–2.37 mmol/L, respectively) had 38% (95% CI: 27%, 50%) and 8% (95% CI: 0%, 17%) higher adjusted monthly costs, respectively. Adjusted costs were 25% (95% CI: 18%, 32%) lower among patients with baseline phosphate levels below the target range. Results were consistent in sensitivity analyses.

Conclusions

These data suggest that elevated SHPT parameters increase the economic burden of CKD in Europe.

Monthly continuous erythropoietin receptor activator treatment maintains stable hemoglobin levels in routine clinical management of hemodialysis patients

Once-monthly administration of CERA, a continuous erythropoietin receptor activator, has shown equivalent efficacy to shorter-acting erythropoiesis-stimulating agents (ESAs) that require more frequent dosing, but data on routine use of once-monthly CERA in hemodialysis patients are lacking. Study on Efficacy, Safety and Applicability of Mircera (SESAM) was a prospective, multicenter, noninterventional trial with a duration of up to 9 months (month 0-5 "titration phase"; month 6-8 "evaluation phase") to test the stability of Hb control in hemodialysis patients under routine conditions. Patient selection, Hb targets and CERA dosing were at the discretion of the local nephrologist. 918 patients from 92 German nephrology centers were included. Ninety-three percent were on ESA treatment prior to study entry. The mean number of CERA dose changes during the study was 1.9 ± 1.9 per patient. Mean Hb level was 11.4 ± 1.2 g/dL at baseline and 11.7 ± 1.4 g/dL at the end of the 8-month study. During the evaluation phase (months 6-8), 15.6%, 40.3%, and 66.0% of patients had stable Hb (i.e., at least two values) in the ranges 11-12, 10-12, and 10-13 g/dL, respectively. The mean intra-individual fluctuation in Hb was 1.4 ± 0.7 g/dL during the study (0.5 ± 0.4 g/dL during the 3-month evaluation phase). More than 90% of patients, and > 80% of physicians, rated CERA therapy as "very good" or "good" throughout the study. Four patients (0.4%) discontinued prematurely due to adverse drug reactions. Once-monthly CERA therapy maintains stable Hb values with low intra-individual variability and few dose adaptations in hemodialysis patients when administered entirely according to local practice, and the regimen was well-tolerated.

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

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

Erythropoiesis-stimulating agents in renal medicine

The four currently available erythropoiesis-stimulating agents (ESAs), the main drugs for correcting anemia in patients with chronic kidney disease (CKD), are epoetin alfa, epoetin beta, darbepoetin alfa, and continuous erythropoietin receptor activator. The last two have much longer half-lives, which means they can be administered less frequently. The expiry of the patents for epoetin alfa and epoetin beta some years ago opened up the way for the production of a number of biosimilars that are now marketed in the European Union. Because biosimilars cannot be identical to their originator, a complex and still-evolving regulatory policy has been generated, but there are still a number of issues concerning international naming, automatic substitution, and safety. All ESAs are effective in correcting renal anemia and increasing hemoglobin levels, but the choice of which to use should also take into account their pharmacokinetics and pharmacodynamics, their administration route, and economic issues. Following the publication of a number of trials indicating no benefit (and even possible harm) when ESAs are used to aim at near-normal hemoglobin levels in CKD patients, the hemoglobin target has become a major subject of discussion. According to the position statement of the Anemia Group of the European Renal Best Practice, it should generally be about 11-12 g/dL; however, a risk-benefit evaluation is warranted in individual patients, and high ESA doses driven by hyporesponsiveness should be avoided.

Erythropoiesis-stimulating agents, hypertension and left ventricular hypertrophy in the chronic kidney disease patient

PURPOSE OF REVIEW

Left-ventricular hypertrophy (LVH) represents an important marker of cardiovascular morbidity and mortality. Numerous noninterventional studies in patients with chronic kidney disease (CKD) revealed a consistent relationship of LVH with modifiable risk factors attributable to failing renal function, particularly anemia and hypertension.

RECENT FINDINGS

Given the clear role for anemia in initiating or accelerating LVH, it seems imperative to correct renal anemia with erythropoiesis-stimulating agents (ESAs). A few nonrandomized studies have described a regression of LVH with correction of anemia, but prospective randomized trials showed no evidence that ESA treatment is able to improve cardiac prognosis in the CKD patient. Current data alert physicians that normalization of hemoglobin in patients with advanced CKD is harmful. Recent studies are now trying to clarify the mechanisms for harm focussing on the influence of comorbidities, ESA doses, and hemoglobin variability. The pathogenesis of hypertension in CKD is multifactorial and only a small percentage of CKD patients have controlled their blood pressure, indicating poor medication adherence, insufficient control of volume overload and undertreatment.

SUMMARY

This review provides an update of ESA treatment, hypertension and LVH in the CKD patient, indicating that pathogenesis of LVH in this population is currently not completely understood. In addition, the impact of pharmacological interventions targeted to prevent or reduce LVH in anemic or hypertensive CKD patients is not well defined. As adoption of the Framingham approach seems not feasible in the CKD patient, evidence from large-scale randomized clinical trials is mandatory to resolve this dilemma.

Effect of dialysate calcium concentrations on parathyroid hormone and calcium balance during a single dialysis session using bicarbonate hemodialysis: a crossover clinical trial

BACKGROUND

In bicarbonate-based hemodialysis, dialysate total calcium (tCa) concentration may have effects on mineral metabolism.

STUDY DESIGN

Randomized crossover trial of 3 dialysate tCa concentrations (2.5, 2.75, and 3.0 mEq/L).

SETTING & PARTICIPANTS

22 stable anuric uremic patients underwent three 4-hour bicarbonate hemodialysis sessions with the 3 different dialysate tCa concentrations using a single-pass batch dialysis system.

OUTCOMES

Hourly measurements of plasma water ionized calcium (iCa) and plasma parathyroid hormone (PTH) concentrations. tCa mass balances were measured from the dialysate side.

RESULTS

Hourly plasma water iCa concentrations were higher with a dialysate tCa concentration of 3.0 compared with 2.75 and 2.5 mEq/L (P < 0.05), as were iCa concentrations at the end of dialysis sessions (2.66 ± 0.1, 2.56 ± 0.12, and 2.4 ± 0.08 mEq/L, respectively; P < 0.001). Mean tCa mass balance values (diffusion gradient from the dialysate to the patient) were positive with all dialysate tCa concentrations and increased progressively with dialysate tCa concentration (75 ± 122, 182 ± 125, and 293 ± 228 mg, respectively; P < 0.001). Plasma PTH levels increased during dialysis using dialysate tCa concentration of 2.5 mEq/L (mean increase, 225 ± 312 pg/mL) and decreased with dialysate tCa concentrations of 2.75 and 3.0 mEq/L (mean decreases, 68 ± 325 and 99 ± 432 pg/mL, respectively).

LIMITATIONS

Small sample size and lack of measurement of total-body calcium mass balances.

CONCLUSIONS

A dialysate tCa concentration of 2.75 mEq/L might be preferable to 2.5 or 3.0 mEq/L because it is associated with mildly positive tCa mass balance values, plasma water iCa levels in the reference range, and stable PTH levels during dialysis.

Simplifying anemia management in hemodialysis patients: ESAs administered at longer dosing intervals can enhance opportunities to provide patient-focused care

OBJECTIVE

To review issues and challenges in caring for hemodialysis patients with anemia of chronic kidney disease, specifically focusing on the effects of longer erythropoiesis-stimulating agent (ESA) dosing intervals on processes of care.

METHODS

PubMed searches were performed limited to the last 10 years to February 2011, focusing on articles in English that were 'clinical trials,' assessed processes of care, measured associations of hemoglobin (Hb) with outcomes, and explored/analyzed extended dosing intervals of ESAs in hemodialysis patients and recommendations for increasing the quality of care of these patients. Some limitations included the fact that a meta-analysis was not conducted; many studies were associative and therefore unable to prove causality; and none of the clinical trials directly compared the impact of more frequent or less frequent ESA dosing strategies on patient care and outcomes.

FINDINGS

Progress over the past several decades has been substantial; however, unmet needs remain and there is room for improvement in efficiencies of care. Many patients fail to meet Hb targets, and nephrology professionals' time is consumed with preparing, administering, and monitoring therapy. Direct interaction between patients and care providers has been lost as attention has shifted to 'cost-effective' (not necessarily patient-centered) ways to deliver care. Use of ESAs at longer dosage intervals represents one opportunity to improve efficiency of care. Newer ESAs have been developed for less frequent dosing. Once-monthly dosing decreases time spent administering/monitoring therapy and allows nephrology professionals to provide comprehensive renal care, wherein the patient rather than task-oriented processes becomes the primary focus.

CONCLUSIONS

A fragmented, uncoordinated care-delivery model heightens the urgency to systematically address issues related to delivery of care and improve efficiencies in anemia management as part of the patient-centered approach. ESAs designed for administration at longer intervals may effectively and reliably achieve Hb targets with once-monthly dosing, thereby decreasing time spent administering/monitoring therapy.

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.