Abstract
Objectives
To compare serum ferritin and RET-He values among extremely low gestational age neonates ELGANs with other markers of iron-deficient erythropoiesis.
Study Design
This is a secondary analysis of the NICHD Darbepoetin Trial. Study data from placebo recipients who had a serum ferritin, a RET-He, and a mean corpuscular volume (MCV) measurement within a 24-hour period were analyzed for correlation.
Results
Mixed linear regression models showed no association between ferritin and RET-He at both early (β = 0.0016, p = 0.40) and late (β = −0.0001, p = 0.96) time points. Positive associations were observed between RET-He and MCV at baseline, early, and late time points (p < 0.01, =0.01, <0.001, respectively), while ferritin was not associated with MCV at any time point.
Conclusions
Our study shows that RET-He is better correlated with MCV as a marker of iron-limited erythropoiesis than ferritin. The results suggest that ferritin is limited as a marker of iron sufficiency in premature infants.
Study Identification
FDA IND Number 100138; ClinicalTrials.gov number NCT03169881; NRN ID number NICHD-NRN-0058 (Darbe).
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Data availability
Inquiries regarding data access can be addressed to the corresponding author.
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Acknowledgements
The National Institutes of Health, the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), and the NIH National Heart Lung and Blood Institute (NHLBI) provided grant support for the Neonatal Research Network’s Darbepoetin Trial through cooperative agreements. While NICHD staff had input into the study design, conduct, analysis, and manuscript drafting, the comments and views of the authors do not necessarily represent the views of NICHD, the National Institutes of Health, the Department of Health and Human Services, or the U.S. Government. Participating NRN sites collected data and transmitted it to RTI International, the data coordinating center (DCC) for the network, which stored, managed and analyzed the data for this study. On behalf of the NRN, RTI International had full access to all of the data in the study, and with the NRN Center Principal Investigators, takes responsibility for the integrity of the data and accuracy of the data analysis.We are indebted to our medical and nursing colleagues and the infants and their parents who agreed to take part in this study.
Funding
Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (UG1HD087226) and by a grant from the NIH National Heart Lung and Blood Institute (U01HL136318).
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TMB: collection and assembly of data, data analysis and interpretation, manuscript writing, editing and final approval of manuscript. ST, ES, AD: collection and assembly of data, editing and final approval of manuscript. data analysis and interpretation, editing and final approval of manuscript. SSB, KRS, CAG, JRL, EFB, ARL, SS, DPC, CR, JF, KZ, MCW: conception and design, data interpretation, manuscript writing, editing and final approval of manuscript. RDC, MCB, RKO: conception and design, collection and assembly of data, manuscript writing, data analysis and interpretation, editing and final approval of manuscript.
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Bahr, T.M., Tan, S., Smith, E. et al. Serum ferritin values in neonates <29 weeks’ gestation are highly variable and do not correlate with reticulocyte hemoglobin content. J Perinatol 43, 1368–1373 (2023). https://doi.org/10.1038/s41372-023-01751-z
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DOI: https://doi.org/10.1038/s41372-023-01751-z