Ferritin Trajectories over Repeated Whole Blood Donations: Results from the FIND+ Study

Abstract

Background: Depending on post-donation erythropoiesis, available iron stores, and iron absorption rates, optimal donation intervals may differ between donors. This project aims to define subpopulations of donors with different ferritin trajectories over repeated donations. Methods: Ferritin levels of 300 new whole blood donors were measured from stored (lookback) samples from each donation over two years in an observational cohort study. Latent classes of ferritin level trajectories were investigated separately using growth mixture models for male and female donors. General linear mixed models assessed associations of ferritin levels with subsequent iron deficiency and/or low hemoglobin. Results: Two groups of donors were identified using group-based trajectory modeling in both genders. Ferritin levels showed rather linear reductions among 42.9% of male donors and 87.7% of female donors. For the remaining groups of donors, steeper declines in ferritin levels were observed. Ferritin levels at baseline and the end of follow-up varied greatly between groups. Conclusion: Repeated ferritin measurements show depleting iron stores in all-new whole blood donors, the level at which mainly depends on baseline ferritin levels. Tailored, less intensive donation strategies might help to prevent low iron in donors, and could be supported with ferritin monitoring and/or iron supplementation.

A computational model for prediction of ferritin and haemoglobin levels in blood donors

“…The FIND+ cohort comprised 300 new whole blood donors who started donating in September 2017, were followed‐up until September 2019, and donated at least twice in this period (Table 1). 22 In all, 25.7% of donors had a baseline ferritin level of <30 ng/ml, of which 96.1% was female. As only 10.6% and 3.5% of female donors were aged >45 and >55 years respectively, the proportion of new female donors that were postmenopausal was very small.…”

“…The operator is then allowed to take the highest value of the measurements if the difference between these measurements is not >0.3 mM. Ferritin was measured from venous samples as described previously 22 . Briefly, 850 μl plasma from K3‐EDTA coated tubes was stored at −30°C in 96‐well plates until further analysis.…”

“…Ferritin was measured from venous samples as described previously. 22 Briefly, 850 μl plasma from K3-EDTA coated tubes was stored at −30°C in 96-well plates until further analysis. At 1 day before testing, plates were defrosted.…”

Effectiveness of Ferritin-guided Donation Intervals in Blood Donors: Results of the Stepped-wedge Cluster Randomised FIND’EM Trial

“…This allows more recovery time from donations. Additionally, because of more stable iron stores due to the healthy donor effect, their lower donation frequency and baseline ferritin levels, the remaining pool of premenopausal donors may not show associations as strong as the other groups (25,26).…”

“…We measured ferritin levels on the Architect i2000sr (Abbott Diagnostics) in plasma samples collected at donation in K3EDTA tubes (VACUETTE®, Greiner Bio-One, Kremsmünster, Austria) and stored at −30⁰C for three to 24 months. 19…”