Parenteral iron use: Possible contribution to exceeding target hemoglobin in hemodialysis patients

Background and objectives: Use of parenteral iron for anemia management in dialysis patients has greatly increased. Exceeding hemoglobin target levels is not without risk, and whether parenteral iron administration contributes to exceeding targets has not been tested. The authors aimed to determine prevalence of parenteral iron administration and its contribution to exceeding hemoglobin target levels. Design, setting, participants, & measurements: The authors performed a retrospective observational study of 149,292 hemodialysis patients using Centers for Medicaid & Medicare Services data. All patients were point prevalent on January 1, 2004; survived through June 30, 2004; had Medicare as primary payer; were treated with erythropoiesis stimulating agents (ESAs); and had valid hemoglobin values in April, May, and June, 2004. Results: Of the cohort, 58% received parenteral iron; use was more likely among men, whites, younger patients, and patients with end-stage renal disease as a result of diabetes. Age > 75 yr, African American and other races, baseline hemoglobin > 12 g/dl, higher ESA dose, and iron use in months 1 to 4 of the study period were independently associated with the risk of exceeding hemoglobin levels of 12, 13, and 14 g/dl. Receiving iron in month 4 of the study period showed the highest probability of exceeding targets (odds ratios 1.49, 1.43, 1.50 for hemoglobin levels 12, 13, 14 g/dl, respectively). Conclusions: Parenteral iron use is prevalent, and although adequate iron stores are central to ESA response, iron use may contribute to exceeding recommended hemoglobin levels. Only data from a prospective trial can confirm this association.