Trends in anemia care in older patients approaching end-stage renal disease in the United States (1995-2010)

Causes of Hospitalization among End-Stage Kidney Disease Cohort before and after Hemodialysis

Patients with end-stage kidney disease (ESKD) have a greater risk of comorbidities, including diabetes and anemia, and have higher hospital admission rates than patients with other diseases. The cause of hospital admissions is associated with ESKD prognosis. This retrospective cohort study involved patients with ESKD who received hemodialysis and investigated whether the cause of hospital admission changed before versus after they started hemodialysis. This study recruited 592 patients with ESKD who received hemodialysis at any period between January 2005 and November 2017 and had been assigned the International Classification of Diseases Ninth Revision Clinical Modification (ICD-9-CM) code for ESKD. The patients' demographic data and hospitalization status one year before and two years after they received hemodialysis were analyzed. A McNemar test was conducted to analyze the diagnostic changes from before to after hemodialysis in patients with ESKD. The study's sample of patients with ESKD comprised more women (51.86%) than men and had an average age of 67.15 years. The numbers of patients admitted to the hospital for the following conditions all decreased significantly after they received hemodialysis: type 2 (non-insulin-dependent and adult-onset) diabetes; native atherosclerosis; urinary tract infection; gastric ulcer without mention of hemorrhage, perforation, or obstruction; pneumonia; reflux esophagitis; duodenal ulcer without mention of hemorrhage, perforation, or obstruction; and bacteremia. Most patients exhibited one or more of the following comorbidities: diabetes (n = 407, 68.75%), hypertension (n = 491, 82.94%), congestive heart failure (n = 161, 27.20%), ischemic heart disease (n = 125, 21.11%), cerebrovascular accident (n = 93, 15.71%), and gout (n = 96, 16.22%). An analysis of variance (ANOVA) indicated that changes in the ICD-9-CM codes for native atherosclerosis, urinary tract infection, pneumonia, and hyperkalemia were associated with age. Patients who developed pneumonia before or after they received hemodialysis tended to be older (range: 69-70 years old). This study investigated the causes of hospital admission among patients with ESKD one year before and two years after they received hemodialysis. This study's results revealed hypertension to be the most common comorbidity. Regarding the cause of admission, pneumonia was more prevalent in older than in younger patients. Moreover, changes in the ICD-9-CM codes of native atherosclerosis, urinary tract infection, pneumonia, and hyperkalemia were significantly correlated with age. Therefore, when administering comprehensive nursing care and treatment for ESKD, clinicians should not only focus on comorbidities but also consider factors (e.g., age) that can affect patient prognosis.

Risk of Infection Associated With Administration of Intravenous Iron: A Systematic Review and Meta-analysis

IMPORTANCE

Intravenous iron is recommended by many clinical guidelines based largely on its effectiveness in reducing anemia. However, the association with important safety outcomes, such as infection, remains uncertain.

OBJECTIVE

To examine the risk of infection associated with intravenous iron compared with oral iron or no iron.

DATA SOURCES

Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for randomized clinical trials (RCTs) from 1966 to January 31, 2021. Ongoing trials were sought from ClinicalTrials.gov, CENTRAL, and the World Health Organization International Clinical Trials Search Registry Platform.

STUDY SELECTION

Pairs of reviewers identified RCTs that compared intravenous iron with oral iron or no iron across all patient populations, excluding healthy volunteers. Nonrandomized studies published since January 1, 2007, were also included. A total of 312 full-text articles were assessed for eligibility.

DATA EXTRACTION AND SYNTHESIS

Data extraction and risk of bias assessments were performed according to the Preferred Reporting Items of Systematic Reviews and Meta-analyses (PRISMA) and Cochrane recommendations, and the quality of evidence was assessed using the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) approach. Two reviewers extracted data independently. A random-effects model was used to synthesize data from RCTs. A narrative synthesis was performed to characterize the reporting of infection.

MAIN OUTCOMES AND MEASURES

The primary outcome was risk of infection. Secondary outcomes included mortality, hospital length of stay, and changes in hemoglobin and red blood cell transfusion requirements. Measures of association were reported as risk ratios (RRs) or mean differences.

RESULTS

A total of 154 RCTs (32 920 participants) were included in the main analysis. Intravenous iron was associated with an increased risk of infection when compared with oral iron or no iron (RR, 1.17; 95% CI, 1.04-1.31; I2 = 37%; moderate certainty of evidence). Intravenous iron also was associated with an increase in hemoglobin (mean difference, 0.57 g/dL; 95% CI, 0.50-0.64 g/dL; I2 = 94%) and a reduction in the risk of requiring a red blood cell transfusion (RR, 0.93; 95% CI, 0.76-0.89; I2 = 15%) when compared with oral iron or no iron. There was no evidence of an effect on mortality or hospital length of stay.

CONCLUSIONS AND RELEVANCE

In this large systematic review and meta-analysis, intravenous iron was associated with an increased risk of infection. Well-designed studies, using standardized definitions of infection, are required to understand the balance between this risk and the potential benefits.

A five-year longitudinal study of the relation between end-stage kidney disease as the outcomes

Background

Patients with end-stage kidney disease (ESKD) are required to undergo consecutive time-based blood and biochemical tests to determine the progression of the disease according to changes in their blood and biochemical data. This study employed a random intercept model to investigate whether time-based blood and biochemical data present any notable clinical meaning that can be used to track disease progression.

Methods

This study conducted a retrospective analysis on the dialytic data of 148 patients with ESKD, who received hemodialysis between January 2005 and December 2015. The patients were all at least 20 years old, and the data used included patient demographic information and results for at least 60 blood and biochemical tests. A random intercept model was used to analyze the relationships among blood and biochemical test results, explanatory variables of patient comorbidities, and time.

Results

The age range of patients was between 33 and 98 years, with an average of 66.1 years and those over 65 years old comprising 51.3% (n = 76) of the total. Furthermore, hypertension was found to be the most common comorbidity among patients (87.2%, n = 129), followed by anemia (48.6%, n = 72), diabetes (47.3%, n = 70), dyslipidemia (19.6%, n = 29), and peptic ulcer (19.6%, n = 29). Coronary atherosclerotic heart disease is a comorbidity that can serve as a strong and independent marker for prognosis in patients with ESKD. Serum creatinine level can serve as an alternative indicator because patients with ESKD and comorbid diabetes may exhibit increased creatinine levels.

Conclusions

The results of a parameter estimation for longitudinal data analysis suggested that comorbidity and time were critical variables influencing blood and biochemical test results. Furthermore, WBC and HBC, HCT, albumin, protein, and creatinine levels were recognized as variables of critical significance. The results obtained in this study indicate that multimorbidity increases the treatment burden on patients, leading to polypharmacy. For this reason, comprehensive care and treatment of ESKD cannot rely solely on data from one single time point; instead, longitudinal analysis and other data that can affect patient prognosis must also be considered.

Understanding Trends in Medicare Spending, 2007-2014

OBJECTIVES

To analyze the sources of per-beneficiary Medicare spending growth between 2007 and 2014, including the role of demographic characteristics, attributes of Medicare coverage, and chronic conditions.

DATA SOURCES

Individual-level Medicare spending and enrollment data.

STUDY DESIGN

Using an Oaxaca-Blinder decomposition model, we analyzed whether changes in price-standardized, per-beneficiary Medicare Part A and B spending reflected changes in the composition of the Medicare population or changes in relative spending levels per person.

DATA EXTRACTION METHODS

We identified a 5 percent sample of fee-for-service Medicare beneficiaries age 65 and above from years 2007 to 2014.

RESULTS

Mean payment-adjusted Medicare per-beneficiary spending decreased by $180 between the 2007-2010 and 2011-2014 time periods. This decline was almost entirely attributable to lower spending levels for beneficiaries. Notably, declines in marginal spending levels for beneficiaries with chronic conditions were associated with a $175 reduction in per-beneficiary spending. The decline was partially offset by the increasing prevalence of certain chronic diseases. Still, we are unable to attribute a large share of the decline in spending levels to observable beneficiary characteristics or chronic conditions.

CONCLUSIONS

Declines in spending levels for Medicare beneficiaries with chronic conditions suggest that changing patterns of care use may be moderating spending growth.

Initiation of erythropoiesis-stimulating agents and outcomes: a nationwide observational cohort study in anaemic chronic kidney disease patients

Background

In 2012, new clinical guidelines were introduced for use of erythropoiesis-stimulating agents (ESA) in chronic kidney disease (CKD) patients, recommending lower haemoglobin (Hb) target levels and thresholds for ESA initiation. These changes resulted in lower blood levels in these patients. However, there is limited evidence on just when ESA should be initiated and the safety of a low Hb initiation policy.

Methods

In this observational inception cohort study, Swedish, nephology-referred, ESA-naïve CKD patients (n = 6348) were enrolled when their Hb dropped below 12.0 g/L, and they were followed for mortality and cardiovascular events. Four different ESA treatments were evaluated applying dynamic marginal structural models: (i) begin ESA immediately, (ii) begin ESA when Hb <11.0 g/dL, (iii) begin ESA when Hb <10.0 g/dL and (iv) never begin ESA in comparison with 'current practice' [the observed (factual) survival of the entire study cohort]. The adjusted 3-year survival following ESA begun over a range of Hb (from <9.0 to 12.0 g/dL) was evaluated, after adjustment for covariates at baseline and during follow-up.

Results

Overall, 36% were treated with ESA. Mortality during follow-up was 33.4% of the ESA-treated and 27.9% of the non-treated subjects. The adjusted 3-year survival associated with ESA initiation improved for subjects with initial Hb <9.0 to 11 g/dL and then decreased again for those with Hb above 11.5 g/dL. Initiating ESA at Hb <11.0 g/dL and <10.0 g/dL was associated with improved survival compared with 'current practice' [hazard ratio (HR) 0.83; 95% confidence interval (CI) 0.79-0.89 and 0.90; 95% CI 0.86-0.94, respectively] and did not increase the risk of a cardiovascular event (HR 0.93; 95% CI 0.87-1.00).

Conclusion

In non-dialysis patients with CKD, ESA initiation at Hb < 10.0-11.0 g/dL is associated with improved survival in patients otherwise treated according to guidelines.

Prevalence, treatment patterns, and healthcare resource utilization in Medicare and commercially insured non-dialysis-dependent chronic kidney disease patients with and without anemia in the United States

BACKGROUND

Anemia is common in non-dialysis-dependent chronic kidney disease (NDD-CKD) patients, but detailed information on prevalence and treatment is lacking.

METHODS

We evaluated anemia prevalence and treatment using two datasets: the Medicare 20% random sample (ages 66-85 years), and the Truven Health MarketScan database (ages 18-63 years). We selected stage 3-5 NDD-CKD patients with and without anemia from both databases during 2011-2013. We evaluated anemia prevalence and treatment (erythropoietin stimulating agents [ESAs], intravenous [IV] iron, red blood cell [RBC] transfusions) following anemia diagnosis during a 1-year baseline period, and healthcare utilization during a 1-year follow-up period. We used Poisson regression models to compare healthcare utilization in patients with and without anemia, adjusting for demographics, baseline comorbid conditions, inflammatory conditions, and CKD stage.

RESULTS

We identified 218,079 older and 56,188 younger stage 3-5 NDD-CKD patients. Anemia prevalence increased with age in both datasets; was higher in women, black patients (Medicare only), and patients with comorbid conditions; and rose sharply with increasing CKD stage. Of 15,716 younger anemic patients, 11.7%, 10.8%, and 9.4% were treated with RBC transfusion, ESAs, and IV iron, respectively. Corresponding proportions of 109,251 older anemic patients were 22.2%, 12.7%, and 6.7%. Regardless of age, anemic patients were more likely than non-anemic patients to use healthcare resources, including hospitalizations and emergency department, hematologist, nephrologist, and outpatient visits. Anemic NDD-CKD patients were more likely to be treated with RBC transfusion than with ESAs or IV iron.

CONCLUSION

More research is necessary to determine best approaches to anemia management in CKD.

Restricted Use of Erythropoiesis-Stimulating Agent is Safe and Associated with Deferred Dialysis Initiation in Stage 5 Chronic Kidney Disease

The effect of erythropoiesis-stimulating agent (ESA) on dialysis initiation in advanced chronic kidney disease (CKD) patients is not clear. We retrospectively analyzed the outcome of dialysis initiation in a stage 5 CKD cohort with ESA reimbursement limited to the maximal standardized monthly ESA dose equivalent to epoetin beta 20,000 U by the National Health Insurance program. Totally 423 patients were followed up for a median of 1.37 year. A time-dependent Cox regression model, adjusted for monthly levels of estimated glomerular filtration rate (eGFR) and hemoglobin, was constructed to investigate the association between ESA and outcome. The standardized monthly ESA dose in ESA users was 16,000 ± 3,900 U of epoetin beta. Annual changes of hemoglobin were −0.29 ± 2.19 and −0.99 ± 2.46 g/dL in ESA users and ESA non-users, respectively (P = 0.038). However, annual eGFR decline rates were not different between ESA users and non-users. After adjustment, ESA use was associated with deferred dialysis initiation (hazard ratio 0.63, 95% confidence interval 0.42–0.93, P = 0.021). The protective effect remained when the monthly ESA doses were incorporated. Our data showed that restricted use of ESA was safe and associated with deferred dialysis initiation in stage 5 CKD patients.

Effects of intravenous iron on fibroblast growth factor 23 (FGF23) in haemodialysis patients: a randomized controlled trial

Background

Intravenous iron affects serum levels of intact fibroblast growth factor-23 (iFGF23) and its cleavage product c-terminal FGF23 (cFGF23) in iron-deficient people with normal renal function. We hypothesized that intravenous iron modulates iFGF23 and cFGF23 in haemodialysis patients differently according to the type of iron used.

Methods

Prevalent, stable haemodialysis patients requiring protocol-based intravenous iron therapy were randomized to a single 200 mg dose of either ferric carboxymaltose (FCM) or iron sucrose (IS). The primary outcome was change in iFGF23 and cFGF23 from pre-infusion to Day 2 post-infusion. Serum hepcidin, ferritin and phosphate were also measured. Pair-wise comparisons utilised the Wilcoxon rank sum test; linear mixed models with an interaction term for treatment and time evaluated between-group effects.

Results

Forty-two participants completed the study. In those randomized to FCM (n = 22), median (interquartile range) values pre-infusion and Day 2, respectively, were 843 pg/mL (313–1922) and 576 pg/mL (356–1296, p = 0.05) for iFGF23, 704RU/mL (475–1204) and 813RU/mL (267–1156, p = 0.04) for cFGF23, and 1.53 mmol/L (1.14–1.71) and 1.37 (1.05–1.67, p = 0.03) for phosphate. These parameters did not change following IS. Both serum ferritin (p < 0.001) and hepcidin (p < 0.001) increased in both groups, and the increase in hepcidin was greater in the FCM group (p = 0.03 for between-group difference).

Conclusions

Contrary to iron-deficient people with normal renal function, haemodialysis patients given protocol-driven intravenous FCM demonstrated a fall in iFGF23 and a rise in cFGF23, changes not evident with IS. This suggests a differential effect of intravenous iron treatment according to both formulation and renal function.

Trial registration

Australian and New Zealand Clinical Trials Register ACTRN12614000548639. Registered 22 May 2014 (retrospectively registered).

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0391-7) contains supplementary material, which is available to authorized users.

Impact of individual intravenous iron preparations on the differentiation of monocytes towards macrophages and dendritic cells

Background

Treatment of iron deficiency with intravenous (i.v.) iron is a first-line strategy to improve anaemia of chronic kidney disease. Previous in vitro experiments demonstrated that different i.v. iron preparations inhibit differentiation of haematopoietic stem cells to monocytes, but their effect on monocyte differentiation to macrophages and mature dendritic cells (mDCs) has not been assessed. We investigated substance-specific effects of iron sucrose (IS), sodium ferric gluconate (SFG), ferric carboxymaltose (FCM) and iron isomaltoside 1000 (IIM) on monocytic differentiation to M1/M2 macrophages and mDCs.

Methods

Via flow cytometry and microRNA (miRNA) expression analysis, we morphologically and functionally characterized monocyte differentiation to M1/M2 macrophages and mDCs after monocyte stimulation with IS, SFG, FCM and IIM (0.133, 0.266 and 0.533 mg/mL, respectively). To assess potential clinical implications, we compared monocytic phagocytosis capacity in dialysis patients who received either 500 mg IS or IIM.

Results

Phenotypically, IS and SFG dysregulated the expression of macrophage (e.g. CD40, CD163) and mDC (e.g. CD1c, CD141) surface markers. Functionally, IS and SFG impaired macrophage phagocytosis capacity. Phenotypic and functional alterations were less pronounced with FCM, and virtually absent with IIM. In miRNA expression analysis of mDCs, IS dysregulated miRNAs such as miR-146b-5p and miR-155-5p, which are linked to Toll-like receptor and mitogen-activated protein kinase signalling pathways. In vivo, IS reduced monocytic phagocytosis capacity within 1 h after infusion, while IIM did not.

Conclusions

This study demonstrates that less stable i.v. iron preparations specifically affect monocyte differentiation towards macrophages and mDCs.

Erythropoiesis-stimulating Agents and Anemia in Patients with Non-dialytic Chronic Kidney Disease

Anemia is common in patients with advanced chronic kidney disease (CKD). Though erythropoiesis-stimulating agents (ESAs) have been strongly endorsed in guidelines, it is of particular financial interest. Recently, the reimbursement of ESAs in non-dialytic patients was started by the Korean National Health Insurance System. Thus, we investigated the impact of the reimbursement of ESAs on the anemia care in non-dialytic CKD patients. Medical records of patients with advanced CKD (estimated GFR <30 mL/min/1.73 m(2)) were reviewed. Use of ESAs, blood transfusion, and hemoglobin concentrations were analyzed from one year prior to reimbursement to three years following. We used multivariable modified Poisson regression to estimate the utilization prevalence ratio (PRs). A total of 1,791 medical records were analyzed. The proportion of patients receiving ESAs increased from 14.8% before reimbursement to a peak 33.6% in 1 yr after reimbursement; thereafter, ESA use decreased to 22.4% in 3 yr after reimbursement (compared with baseline; PR, 2.19 [95% CI, 1.40-3.42]). In patients with Hb <10 g/dL, the proportion of receiving ESAs increased from 32.1% before reimbursement to 66.7% in 3 yr after reimbursement (compared with baseline; PR, 2.04 [95% CI, 1.25-3.32]). Mean hemoglobin concentrations were 10.06±1.54 g/dL before reimbursement and increased to 10.78±1.51 g/dL in 3 yr after the reimbursement change (P=0.001). However, the requirement of blood transfusion was not changed over time. With the reimbursement of ESAs, the advanced CKD patients were more likely to be treated with ESAs, and the hemoglobin concentrations increased.

Trends in Anemia Management in Hemodialysis Patients with Cancer

BACKGROUND

Erythropoiesis-stimulating agents (ESAs), intravenous iron, and blood transfusion are used to treat anemia in both end-stage renal disease (ESRD) and cancer. However, anemia treatment patterns have not been described among ESRD patients undergoing hemodialysis with concurrent cancer, especially in the recent era of ESA-related safety concerns.

METHODS

We analyzed Medicare data from a cohort of hemodialysis patients diagnosed with incident cancer. We used multivariable generalized linear models to estimate trends and patterns in ESA use, iron use, transfusion use, epoetin alfa (EPO) dose, iron dose, and resulting hemoglobin levels (2000-2011).

RESULTS

Of 43,760 eligible patients, quarterly ESA use declined slightly from a peak of 94.1 to 90.0%. Quarterly EPO dose increased from 2000 to 2004, then declined; quarterly hemoglobin levels followed a similar pattern. Iron use increased rapidly from 46.9 to 79.3%. Iron dose increased until 2010 and then declined. There was an increase in the quarterly transfusion use (6.3-11.7%) and in the mean number of transfusion days per year (1.4-1.8). Anemia treatment patterns varied by demographic/clinical subgroups, especially among patients receiving chemotherapy, who required higher ESA use, EPO dose, and frequency of transfusions.

CONCLUSIONS

Despite safety concerns about ESAs in both the ESRD and cancer populations, the proportion of hemodialysis patients with cancer who used ESAs between 2000 and 2011 remained extremely high. EPO dose and hemoglobin levels increased and then decreased. Iron use, iron dose, and transfusions increased substantially. Future research examining the risk-benefit profile of different anemia management strategies in the dialysis population with cancer is needed.

Severity of Anemia Predicts Hospital Length of Stay but Not Readmission in Patients with Chronic Kidney Disease: A Retrospective Cohort Study

The aim of this study was to examine the relationship of severe anemia to hospital readmission and length of stay (LOS) in patients with chronic kidney disease (CKD) stage 3-5. Compared with the general population, patients with moderate CKD have a higher hospital readmission rate and LOS. Anemia in patients with moderate CKD is associated with higher morbidity and mortality. The influence of anemia on hospital outcomes in patients with moderate CKD has not been characterized.We conducted a retrospective cohort study at Maine Medical Center, a 606-bed academic tertiary care hospital. Patients with CKD stages 3-5 and not on dialysis admitted during February 2013 to January 2014 were eligible. Patients with end stage renal disease on hemodialysis or peritoneal dialysis, kidney transplant, acute kidney injury, gastrointestinal bleeding, active malignancy, pregnancy, and surgery were excluded. The cohort was split into severe anemia (hemoglobin ≤9  g/dL) versus a comparison group (hemoglobin >9 g /dL), and examined for differences in 30-day hospital readmission and LOS.In this study, the data of 1141 patients were included, out of which 156 (13.7%) had severe anemia (mean hemoglobin 8.1 g/dL, SD 0.8). Severe anemia was associated with increased hospital LOS (mean 6.4 (SD 6.0) days vs mean 4.5 (SD 4.0) days, P < 0.001). The difference was 1.7 day longer (95% CI 0.94, 2.45). There was no difference in readmission rate (mean 11.5% vs 10.2%, P = 0.7).Patients with moderate CKD and severe anemia are at risk for increased hospital LOS. Interventions targeting this high-risk population, including outpatient management of anemia, may benefit patient care and save costs through improved hospital outcomes.