title: Iron deficiency, anemia, and mortality in renal transplant recipients.
abstract: Anemia, iron deficiency anemia (IDA), and iron deficiency (ID) are highly prevalent in renal transplant recipients (RTR). Anemia is associated with poor outcome, but the role of ID is unknown. Therefore, we aimed to investigate the association of ID, irrespective of anemia, with all-cause mortality in RTR. Cox regression analyses were used to investigate prospective associations. In 700 RTR, prevalences of anemia, IDA, and ID were 34%, 13%, and 30%, respectively. During follow-up for 3.1 (2.7-3.9) years, 81 (12%) RTR died. In univariable analysis, anemia [HR, 1.72 (95%CI: 1.11-2.66), P = 0.02], IDA [2.44 (1.48-4.01), P < 0.001], and ID [2.04 (1.31-3.16), P = 0.001] were all associated with all-cause mortality. In multivariable analysis, the association of anemia with mortality became weaker after adjustment for ID [1.52 (0.97-2.39), P = 0.07] and disappeared after adjustment for proteinuria and eGFR [1.09 (0.67-1.78), P = 0.73]. The association of IDA with mortality attenuated after adjustment for potential confounders. In contrast, the association of ID with mortality remained independent of potential confounders, including anemia [1.77 (1.13-2.78), P = 0.01]. In conclusion, ID is highly prevalent among RTR and is associated with an increased risk of mortality, independent of anemia. As ID is a modifiable factor, correction of ID could be a target to improve survival.
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. m.f.eisenga@umcg.nl.
authors: Michele F
authors: MF
authors: Eisenga
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.|Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Isidor
authors: I
authors: Minović
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Stefan P
authors: SP
authors: Berger
authors: Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Jenny E
authors: JE
authors: Kootstra-Ros
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Else
authors: E
authors: van den Berg
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.|Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Ineke J
authors: IJ
authors: Riphagen
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Gerjan
authors: G
authors: Navis
authors: Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Peter
authors: P
authors: van der Meer
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Stephan J L
authors: SJ
authors: Bakker
authors: Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Carlo A J M
authors: CA
authors: Gaillard
mesh_terms: D000328:Adult; D000368:Aged; D018798:Anemia, Iron-Deficiency / Q000150:complications / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007501:Iron / Q000097:blood; D000090463:Iron Deficiencies; D053208:Kaplan-Meier Estimate; D016030:Kidney Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000401:mortality* / Q000601:surgery*; D066027:Transplant Recipients; D016896:Treatment Outcome
chemical_list: D007501:Iron
keywords: anemia; iron deficiency; kidney transplantation; mortality