The Comparative Short-term Effectiveness of Iron Dosing and Formulations in US Hemodialysis Patients

Abstract

BACKGROUND Intravenous iron is used widely in hemodialysis, yet there are limited data on the effectiveness of contemporary dosing strategies or formulation type. METHODS We conducted a retrospective cohort study using data from the clinical database of a large dialysis provider (years 2004–2008) merged with administrative data from the United States Renal Data System to compare the effects of intravenous iron use on anemia management. Dosing comparisons were (1) bolus (consecutive doses ≥100 mg exceeding 600 mg during one month) versus maintenance (all other iron doses during the month); and (2) high (> 200 mg over 1 month) versus low dose (≤200 mg over 1 month). Formulation comparison was administration of ferric gluconate versus iron sucrose over one month. Outcomes were hemoglobin, epoetin dose, transferrin saturation, and serum ferritin during 6 weeks of follow-up. RESULTS We identified 117,050 patients for the dosing comparison, and 66,207 patients for the formulation comparison. Bolus dosing was associated with higher average adjusted hemoglobin (+0.23 g/dl, 95% C.I. 0.21–0.26), transferrin saturation (+3.31% 95% C.I. 2.99–3.63), serum ferritin (+151 mcg/L, 95% C.I. 134.9–168.7), and lower average epoetin dose (-464 units 95% C.I. -583 to -343) compared to maintenance. Similar trends were observed with high dose iron versus low dose. Iron sucrose was associated with higher adjusted average hemoglobin (+0.16 g/dl, 95% C.I. 0.12–0.19) versus ferric gluconate. CONCLUSIONS Strategies favoring large doses of intravenous iron or iron sucrose lead to improved measures of anemia management. These potential benefits should be weighed against risks, which currently, remain incompletely characterized.

What are the Considerations in Balancing Benefits and Risks in Iron Treatment?

“…In a large population of hemodialysis patients, we identified short-term benefits of bolus iron administration on hemoglobin levels and iron status relative to more conservative maintenance dosing. 18 Our results were compatible with those observed in the DRIVE trial. 19 In subsequent studies, we did not observe any cardiovascular risks associated with the use of iron; 20,21 however, we did observe a modestly increased risk of infection associated with bolus dosing among patients with a history of infection and those with a central venous hemodialysis catheter.…”

Cancer Incidence Among US Medicare ESRD Patients Receiving Hemodialysis, 1996-2009

“…18 A subsequent 6-month period (ie, the baseline period) was required for assessment of cancer-free status, as done previously. 19-21 History of kidney transplantation evaluation was defined as a claim assigned a V code of V72.83 (other specified preoperative examination) during the 6-month baseline period. Sensitivity and specificity of code V72.83 have not been reported.…”

How we diagnose and treat iron deficiency anemia

“…The approved indications for each of the iron formulations are shown in Table V. LMW iron dextran is only approved as a 100-mg bolus injection over 2 min. However, there is ample literature demonstrating the safety and efficacy of complete replacement dosing of 1,000 mg or more administered in 1-4 hr [56][57][58]. In our practice, we routinely administer 1,000 mg of LMW iron dextran in 1 hr in 250 mg of normal saline without premedication except in those patients with allergic diatheses consisting of one or more drug allergies or asthma, in which case steroids may decrease minor reactions [54].…”