Background Intravenous iron use in hemodialysis patients has greatly increased over the last decade, despite limited studies on the safety of iron. Methods We studied the association of receipt of intravenous iron with hospitalizations in an incident cohort of hemodialysis patients. We examined 9544 patients from Dialysis Clinic, Inc. (DCI). We ascertained intravenous iron use from DCI electronic medical record and USRDS data files, and hospitalizations through Medicare claims. We examined the association between iron exposure accumulated over 1-, 3- or 6-month time windows and incident hospitalizations in the follow-up period using marginal structural models accounting for time-dependent confounders. We performed sensitivity analyses including recurrent events models for multiple hospitalizations and models for combined outcome of hospitalization and death. Results There were 22 347 hospitalizations during a median follow-up of 23 months. Higher cumulative dose of intravenous iron was not associated with all-cause, cardiovascular or infectious hospitalizations [HR 0.97 (95% CI: 0.77-1.22) for all-cause hospitalizations comparing >2100 mg versus 0-900 mg of iron over 6 months]. Findings were similar in models examining the risk of hospitalizations in 1- and 3-month windows [HR 0.88 (95% CI: 0.79-0.99) and HR 0.88 (95% CI: 0.74-1.03), respectively] or the risk of combined outcome of hospitalization and death in the 6-month window [HR 0.98 (95% CI: 0.78-1.23)]. Conclusions Higher cumulative dose of intravenous iron may not be associated with increased risk of hospitalizations in hemodialysis patients. While clinical trials are needed, employing higher iron doses to reduce erythropoiesis-stimulating agents does not appear to increase morbidity in routine clinical care.
Bibliographical noteFunding Information:
The Developing Evidence to Inform Decisions about Effectiveness (DEcIDE) Network Patient Outcomes in ESRD Study was supported by the Agency for Healthcare Research and Quality (AHRQ) contract HHSA290200500341I, Task Order #6. The DEcIDE Network Patient Outcomes in End-Stage Renal Disease Study Team consists of members from the Johns Hopkins University, Baltimore, MD (L. Ebony Boul-ware, Karen Bandeen-Roche, Courtney Cook, Josef Coresh, Deidra Crews, Patti Ephraim, Bernard Jaar, Jeonyong Kim, Yang Liu, Jason Luly, Aidan McDermott, Wieneke Michels, Paul Scheel, Tariq Shafi, Stephen Sozio, Albert Wu, Jing Zhou); University of California, San Francisco, CA (Neil Powe); Chronic Disease Research Group, Minneapolis, MN (Allan Collins, Robert Foley, David Gilbertson, Haifeng Guo, Brooke Heubner, Charles Herzog, Jiannong Liu, Wendy St Peter); Cleveland Clinic Foundation, Cleveland, OH (Joseph Nally, Susana Arrigain, Stacey Jolly, Vicky Konig, Xiaobo Liu, Sankar Navaneethan, Jesse Schold,); University of New Mexico, Albuquerque, NM (Philip Zager); Tufts University, Boston, MA (Dana Miskulin, Klemens Meyer); University of Miami, Miami, FL (Julia Scialla); University of Manitoba, Winnipeg, Manitoba (Navdeep Tangri); and Academic Medical Center, Amsterdam, The Netherlands (Wieneke Michels). The authors express their gratitude to the staff and patients of Dialysis Clinic, Inc. This project is supported by the DEcIDE Network AHRQ contract number HHSA290200500341I, Task Order #6. D.C. was supported by the Amos Medical Faculty Development Program of the Robert Wood Johnson Foundation, Princeton NJ. T.S. was supported by K23DK083514 and J.S. was supported by K23DK095949 from the National Institute of Diabetes and Digestive and Kidney Diseases. W.M. was supported by a Postdoctoral Full Fellowship Abroad Grant (KFB 11.005) of the Dutch Kidney Foundation (Nierstichting).
© 2014 © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
- intravenous iron