Canadian Randomized Trial of Hemoglobin Maintenance to Prevent or Delay Left Ventricular Mass Growth in Patients With CKD

University of British Columbia, St Paul's Hospital, Vancouver, British Columbia, Canada.
American Journal of Kidney Diseases (Impact Factor: 5.76). 12/2005; 46(5):799-811. DOI: 10.1053/j.ajkd.2005.08.007
Source: PubMed

ABSTRACT This randomized clinical trial is designed to assess whether the prevention and/or correction of anemia, by immediate versus delayed treatment with erythropoietin alfa in patients with chronic kidney disease, would delay left ventricular (LV) growth. Study design and sample size calculations were based on previously published Canadian data.
One hundred seventy-two patients were randomly assigned. The treatment group received therapy with erythropoietin alfa subcutaneously to maintain or achieve hemoglobin (Hgb) level targets of 12.0 to 14.0 g/dL (120 to 140 g/L). The control/delayed treatment group had Hgb levels of 9.0 +/- 0.5 g/dL (90 +/- 5 g/L) before therapy was started: target level was 9.0 to 10.5 g/dL (90 to 105 g/L). Optimal blood pressure and parathyroid hormone, calcium, and phosphate level targets were prescribed; all patients were iron replete. The primary end point is LV growth at 24 months.
One hundred fifty-two patients were eligible for the intention-to-treat analysis: mean age was 57 years, 30% were women, 38% had diabetes, and median glomerular filtration rate was 29 mL/min (0.48 mL/s; range, 12 to 55 mL/min [0.20 to 0.92 mL/s]). Blood pressure and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use were similar in the control/delayed treatment and treatment groups at baseline. Erythropoietin therapy was administered to 77 of 78 patients in the treatment group, with a median final dose of 2,000 IU/wk. Sixteen patients in the control/delayed treatment group were administered erythropoietin at a median final dose of 3,000 IU/wk. There was no statistically significant difference between groups for the primary outcome of mean change in LV mass index (LVMI) from baseline to 24 months, which was 5.21 +/- 30.3 g/m2 in the control/delayed treatment group versus 0.37 +/- 25.0 g/m2 in the treatment group. Absolute mean difference between groups was 4.85 g/m2 (95% confidence interval, -4.0 to 13.7; P = 0.28). Mean Hgb level was greater in the treatment group throughout the study and at study end was 12.75 g/dL (127.5 g/L in treatment group versus 11.46 g/dL [114.6 g/L] in control/delayed treatment group; P = 0.0001). LV growth occurred in 20.1% in the treatment group versus 31% in the control/delayed treatment group (P = 0.136). In patients with a stable Hgb level, mean LVMI did not change (-0.25 +/- 26.7 g/m2), but it increased in those with decreasing Hgb levels (19.3 +/- 28.2 g/m2; P = 0.002).
This trial describes disparity between observational and randomized controlled trial data: observed and randomly assigned Hgb level and LVMI are not linked; thus, there is strong evidence that the association between Hgb level and LVMI likely is not causal. Large randomized controlled trials with unselected patients, using morbidity and mortality as outcomes, are needed.


Available from: Joel Singer, Apr 20, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives Even though anaemia has been shown to be a risk factor for adverse cardiovascular disease, there is scarce evidence of its relationship with angiographically proven coronary artery disease (CAD). The aim of this study was to evaluate the relationship between haemoglobin (Hb) levels and the extent of CAD. Materials and methods We measured Hb, mean corpuscular volume and red blood cell count in 2363 consecutive patients undergoing coronary angiography. Patients were divided into four groups according to quartile values of Hb (≤12.2 g/dl, group 1; 12.3–13.5 g/dl, group 2; 13.6–14.6 g/dl, group 3; >14.6 g/dl, group 4). Results Patients with lower Hb were older (P<0.001), there was a predominance of women (P<0.0001), and patients had diabetes (P<0.0001), hypertension (P=0.024), renal failure (P<0.0001), previous coronary artery bypass graft (P<0.0001), previous cerebrovascular accident (P=0.039) and platelet count (P<0.0001). In terms of angiographic features, low Hb levels were associated with a larger prevalence of calcified lesions (P<0.001), but a lower prevalence of thrombus-containing lesions (P<0.001). Hb was not associated with the prevalence of CAD [odds ratio (OR) (95% confidence interval (CI))=0.96 (0.89–1.04), P=0.35], whereas an association was observed with the severity of CAD [OR (95% CI)=0.92 (0.85–0.99), P=0.032] that was not confirmed after correction for baseline confounding factors [OR (95% CI)=0.98 (0.89–1.09), P=0.76]. Similar findings were observed for mean corpuscular volume and red blood cell count. Conclusion This study showed that Hb levels are not associated with the prevalence and extent of CAD.
    Coronary Artery Disease 09/2014; 25(6):463-468. DOI:10.1097/MCA.0000000000000103 · 1.30 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Several erythropoiesis-stimulating agents (ESAs) are available for treating anaemia in people with chronic kidney disease (CKD). Their relative efficacy (preventing blood transfusions and reducing fatigue and breathlessness) and safety (mortality and cardiovascular events) are unclear due to the limited power of head-to-head studies. To compare the efficacy and safety of ESAs (epoetin alfa, epoetin beta, darbepoetin alfa, or methoxy polyethylene glycol-epoetin beta, and biosimilar ESAs, against each other, placebo, or no treatment) to treat anaemia in adults with CKD. We searched the Cochrane Renal Group's Specialised Register to 11 February 2014 through contact with the Trials' Search Co-ordinator using search terms relevant to this review. Randomised controlled trials (RCTs) that included a comparison of an ESA (epoetin alfa, epoetin beta, darbepoetin alfa, methoxy polyethylene glycol-epoetin beta, or biosimilar ESA) with another ESA, placebo or no treatment in adults with CKD and that reported prespecified patient-relevant outcomes were considered for inclusion. Two independent authors screened the search results and extracted data. Data synthesis was performed by random-effects pairwise meta-analysis and network meta-analysis. We assessed for heterogeneity and inconsistency within meta-analyses using standard techniques and planned subgroup and meta-regression to explore for sources of heterogeneity or inconsistency. We assessed our confidence in treatment estimates for the primary outcomes within network meta-analysis (preventing blood transfusions and all-cause mortality) according to adapted GRADE methodology as very low, low, moderate, or high. We identified 56 eligible studies involving 15,596 adults with CKD. Risks of bias in the included studies was generally high or unclear for more than half of studies in all of the risk of bias domains we assessed; no study was low risk for allocation concealment, blinding of outcome assessment and attrition from follow-up. In network analyses, there was moderate to low confidence that epoetin alfa (OR 0.18, 95% CI 0.05 to 0.59), epoetin beta (OR 0.09, 95% CI 0.02 to 0.38), darbepoetin alfa (OR 0.17, 95% CI 0.05 to 0.57), and methoxy polyethylene glycol-epoetin beta (OR 0.15, 95% CI 0.03 to 0.70) prevented blood transfusions compared to placebo. In very low quality evidence, biosimilar ESA therapy was possibly no better than placebo for preventing blood transfusions (OR 0.27, 95% CI 0.05 to 1.47) with considerable imprecision in estimated effects. We could not discern whether all ESAs were similar or different in their effects on preventing blood transfusions and our confidence in the comparative effectiveness of different ESAs was generally very low. Similarly, the comparative effects of ESAs compared with another ESA, placebo or no treatment on all-cause mortality were imprecise.All proprietary ESAs increased the odds of hypertension compared to placebo (epoetin alfa OR 2.31, 95% CI 1.27 to 4.23; epoetin beta OR 2.57, 95% CI 1.23 to 5.39; darbepoetin alfa OR 1.83, 95% CI 1.05 to 3.21; methoxy polyethylene glycol-epoetin beta OR 1.96, 95% CI 0.98 to 3.92), while the effect of biosimilar ESAs on developing hypertension was less certain (OR 1.18, 95% CI 0.47 to 2.99). Our confidence in the comparative effects of ESAs on hypertension was low due to considerable imprecision in treatment estimates. The comparative effects of all ESAs on cardiovascular mortality, myocardial infarction (MI), stroke, and vascular access thrombosis were uncertain and network analyses for major cardiovascular events, end-stage kidney disease (ESKD), fatigue and breathlessness were not possible. Effects of ESAs on fatigue were described heterogeneously in the available studies in ways that were not useable for analyses. In the CKD setting, there is currently insufficient evidence to suggest the superiority of any ESA formulation based on available safety and efficacy data. Directly comparative data for the effectiveness of different ESA formulations based on patient-centred outcomes (such as quality of life, fatigue, and functional status) are sparse and poorly reported and current research studies are unable to inform care. All proprietary ESAs (epoetin alfa, epoetin beta, darbepoetin alfa, and methoxy polyethylene glycol-epoetin beta) prevent blood transfusions but information for biosimilar ESAs is less conclusive. Comparative treatment effects of different ESA formulations on other patient-important outcomes such as survival, MI, stroke, breathlessness and fatigue are very uncertain.For consumers, clinicians and funders, considerations such as drug cost and availability and preferences for dosing frequency might be considered as the basis for individualising anaemia care due to lack of data for comparative differences in clinical benefits and harms.
    Cochrane database of systematic reviews (Online) 12/2014; 12(12):CD010590. DOI:10.1002/14651858.CD010590.pub2 · 5.70 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In Europe, epoetin subsequent entry biologics (SEBs) have been in use since 2007. Canadian patents of erythropoietin stimulating agents are expiring in 2014, therefore it is predicted that epoetin SEBs will penetrate the Canadian market in the near future. To estimate the economic impact and costs offsets associated with the uptake and use of one or more epoetin SEBs in Canada for the treatment of anemia in chronic kidney disease. A Canada-wide epidemiological-based budget impact analysis was conducted to estimate cost outcomes under two scenarios: with and without the availability of epoetin SEB. The analysis was conducted from the perspective of the Canadian healthcare payer, over a 5-year time horizon from 2015 to 2019. Patients included in the model were those with chronic kidney disease stages 3 to 5, who have renal anemia and require treatment with erythropoietin stimulating agents. Only direct medical costs pertaining to drug acquisition of currently available erythropoietin stimulating agents in Canada were incorporated in the model. Cost of epoetin SEBs, market shares, uptake rates, and other model inputs were estimated from published sources or databases. No discounting of future costs was applied. Based on our analysis, under market phenomena similar to those seen in the Europe and without considering potential switching from originator epoetin to epoetin SEB, we could expect that Canadian adoption of epoetin SEBs could result in $35 million (2013 CAD, year 1) to $50 million (year 5) cost savings annually, with cumulative savings of $221 million after 5 years. In one-way sensitivity analyses, model variables with substantial impact on cost savings were the prevalence of chronic kidney disease and epoetin SEB uptake rates. We did not take into account costs associated with overhead, administration, or adverse events. The advent of SEBs represents an opportunity to relieve financial pressure in our healthcare system. Under the assumption that the efficacy and safety of epoetin SEBs are non-inferior to originator products, we have shown that the adoption of epoetin SEBs can lead to cost savings for the Canadian payer.
    11/2014; 1:28. DOI:10.1186/s40697-014-0028-3