Maintenance intravenous iron therapy in pediatric hemodialysis patients Morgan H E, Gautam M, Geary D F

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1 Maintenance intravenous iron therapy in pediatric hemodialysis patients Morgan H E, Gautam M, Geary D F Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology Maintenance intravenous (IV) iron supplementation with iron (III) hydroxide sucrose complex (Venofer) was studied. Iron was administered according to a standardised protocol. If transferrin saturation (TSAT) was above 20% but less than 50%, and ferritin was above 100 but less than 800 microg/l, then a 2 mg/kg dose was given once weekly, with a maximum single dose of 100 mg. This intervention was compared with oral iron supplementation with Venofer. Oral iron was prescribed up to a limit of 6 mg/kg. Type of intervention Treatment. Economic study type Cost-effectiveness analysis. Study population The study population comprised paediatric patients on chronic haemodialysis for more than 3 continuous months. Setting The study setting was secondary care. The economic study was carried out in Toronto, Canada. Dates to which data relate The dates to which the effectiveness data related were not reported, although patients in the group receiving oral supplementation (group 1) included those dialysed 18 months prior to the introduction of the new protocol. The price year was not reported. Source of effectiveness data The effectiveness data were derived from a single study. Link between effectiveness and cost data The costing was undertaken prospectively on the same patient sample as that used in the effectiveness study. Study sample No power calculations, to determine the sample size, were reported. In addition, no specific sample size was planned. Fourteen patients were included in group 1, of which 7 (50%) were male. The average age for this group was 11.0 (+/- 5.4) years. Five patients received maintenance IV iron supplementation (group 2), of which 4 were male. The average age of this group was 11.2 (+/- 4.4) years. Page: 1 / 5

2 Study design This was a comparative study with historical controls that was carried out in a single centre. The median duration of follow-up was 5.0 months (range: ) for patients in group 1 and 5.0 months (range: ) for patients in group 2. The authors did not report any loss to follow-up. Analysis of effectiveness It would appear that all the patients included in the study were accounted for in the analysis. The outcomes included were: haematological indices (haemoglobin and reticulocyte count); iron stores (serum iron, ferritin, transferrin, and calculated TSAT); and the mean dose of EPO given. Data on haematological indices and iron stores were routinely collected and retrieved from the case record for patients in each group. Groups were compared using Student's t-test and the Mann-Whitney rank sum test, with p-value of less than 0.05 accepted as significant. The groups were shown to be comparable in terms of gender, age and prognostic features. Effectiveness results There were no statistically significant differences in haematological indices and iron stores between the two groups. No adverse effects were seen in either treatment group. There was a significant reduction in the mean EPO dose given to those patients in group 2 (73.9 +/ units/kg per week) compared with those in group 1( / units/kg per week), (p<0.05). Clinical conclusions The study demonstrated that maintenance IV iron therapy allowed the blood haemoglobin level to be maintained with a lower dose of EPO. Measure of benefits used in the economic analysis No summary measure of benefit was derived. The study was, in effect, a cost-consequences analysis. Direct costs The costs and resource use were not reported separately. The direct costs included in the analysis were those of the hospital. These comprised the costs of the medication doses only. The medication doses were determined from the prescription record and dialysis chart. Relative medication costs were calculated from prices provided by the hospital pharmacy. The total cost for each medication was determined for the duration of therapy, which was then divided to determine a mean cost per month for the whole treatment, adjusted for body weight. Discounting was not relevant, as all the costs were incurred during less than one year, and was not performed. The study reported the median costs. The price year was not reported. Statistical analysis of costs The costs were analysed stochastically, with differences between the groups being tested using Student's t-test. A p- value of less than 0.05 was accepted as significant. Page: 2 / 5

3 Indirect Costs The indirect costs were not included in the analysis. Currency Canadian dollars (Can $). Sensitivity analysis No sensitivity analysis was performed. Estimated benefits used in the economic analysis See the 'Effectiveness Results' section. Cost results Group 2 was associated with a 26% reduction in the combined cost of EPO and iron compared with group 1. The median cost was Can$7.8/kg per month (range: ) in group 2 versus Can$9.3/kg per month (range: ) in group 1, (p=0.33). Synthesis of costs and benefits The costs and benefits were not combined. Authors' conclusions The results suggested that paediatric haemodialysis patients could be more economically treated with maintenance intravenous (IV) iron. CRD COMMENTARY - Selection of comparators Oral iron supplements were chosen as the comparator because they represented current practice in the authors' setting prior to the introduction of the new maintenance iron protocol. You should decide whether the comparator represents current practice in your own setting. Validity of estimate of measure of effectiveness The analysis used a comparative study with historical controls, based on a retrospective analysis of hospital records, which was convenient for the hospital. However, a randomised controlled trial would have been a more reliable source of evidence. The type of study used here has many potential limitations. As this study examined outcomes over two time periods, factors such as improved medical technologies, better health care delivery, new management styles and other such time-related trends, might have explained some of the differences between the groups in terms of the health outcomes and hospital length of stay. The patient groups were shown to be comparable at analysis and no statistically significant differences in age, gender and prognostic features were found between the two groups. However, this might have been due to the small sample size used. Further, the study did not seem of sufficient power to detect any differences in haematological indices and iron stores between the two groups. It was unclear if there was any loss to follow-up during the median 5-month follow-up period. Validity of estimate of measure of benefit The authors did not derive a summary measure of health benefit. The analysis was, in effect, a cost-consequences study. Validity of estimate of costs Page: 3 / 5

4 It was unclear whether all the cost categories were included, as the authors did not report the perspective adopted in the economic analysis. Only the medication costs were included in the analysis. The costs and resource use were not reported separately, which will hamper the generalisability of the authors' results to other settings. The medication costs were derived from the hospital pharmacy. Appropriate statistical techniques were used to test for differences between the two groups. The authors found no statistically significant differences between the two groups in terms of costs. However, the study would appear not to have been powered sufficiently to detect these differences, owing to the small sample size. Discounting was unnecessary as all the costs were incurred during a short time. The price year was not reported, which will hamper any possible inflation exercises. Other issues The authors made appropriate comparisons of their findings with other studies that had found a similar economic benefit of maintenance IV iron in adult patients. The issue of generalisability to other settings was not addressed. The authors do not appear to have presented their results selectively. The authors appropriately concluded that their results suggested that maintenance IV iron was more economical than oral supplements because, even though maintenance was found to be more economical, differences between the groups were not statistically significant. The authors reported no further limitations to their study. Implications of the study Based on their study, the authors would appear to recommend the use of maintenance IV iron therapy over oral supplementation. However, they also indicated that the optimum dose of IV iron required in paediatric patients to improve erthropoiesis, without causing iron overload, was yet to be determined. Source of funding None stated. Bibliographic details Morgan H E, Gautam M, Geary D F. Maintenance intravenous iron therapy in pediatric hemodialysis patients. Pediatric Nephrology 2001; 16(10): PubMedID Other publications of related interest Park L, Uhthoff T, Tierney M, et al. Effects of an intravenous iron dextran regimen on iron stores, hemoglobin, and erythropoietin requirements in hemodialysis patients. American Journal of Kidney Diseases 1998;31: Nyrvad O, Danielsen H, Madsen S. Intravenous iron-sucrose complex to reduce epoietin demand in dialysis patients. Lancet 1994;244: Sepandj F, Jindal K, West M, Hirsch D. Economic appraisal of maintenance parenteral iron administration in treatment of anaemia in chronic haemodialysis patients. Nephrology, Dialysis, Transplantation 1996;11: Indexing Status Subject indexing assigned by NLM MeSH Anemia /etiology /prevention & control; Child; Child, Preschool; Female; Ferritins /blood; Humans; Injections, Intravenous; Iron /administration & dosage /therapeutic use; Kidney Failure, Chronic /metabolism /therapy; Male; Patient Compliance; Renal Dialysis /adverse effects Page: 4 / 5

5 Powered by TCPDF ( AccessionNumber Date bibliographic record published 28/02/2005 Date abstract record published 28/02/2005 Page: 5 / 5