Donor Iron Deficiency Study (DIDS): protocol of a study to test whether iron deficiency in blood donors affects red blood cell recovery after transfusion

Abstract

Background: Despite fulfilling all requirements for blood donation, a large proportion of regular blood donors are iron deficient. Red blood cells (RBC) from iron-deficient donors may be particularly susceptible to damage induced by standard refrigerated storage. Herein, we present a study protocol for testing whether correcting iron deficiency in donors with iron-deficient erythropoiesis will improve the quality of their refrigerator-stored RBC.

Materials and methods: This is a randomised, controlled, double-blind clinical trial. Sixty healthy regular donors who meet donation standards, while exhibiting iron-deficient erythropoiesis by laboratory testing criteria, will donate a single standard RBC unit that will be leucoreduced and stored in a refrigerator under standard conditions for 40-42 days. A ⁵¹Cr-radiolabelled 24-hour RBC recovery study will be performed and then these donors will be randomised to receive, in a double-blinded fashion, either intravenous saline, as a control, or low-molecular weight iron dextran (1 g), to provide total iron repletion. Four to six months later, they will donate a second RBC unit, which will be similarly stored, and autologous ⁵¹Cr-labelled 24-hour post-transfusion RBC recovery will again be determined.

Results: The primary endpoint will be the change in 24-hour post-transfusion recovery from the first to the second donation. The primary outcome will be the group mean difference in the primary endpoints between the group receiving intravenous saline and the group receiving intravenous iron dextran. Secondary outcomes will be quality of life, fatigue, and emotional health, assessed by surveys.

Conclusion: This study will provide definitive evidence as to whether donor iron deficiency affects the quality of the blood supply and will assess the severity of symptoms affecting iron-deficient blood donors.

Figure 1

Study schema. Sixty frequent blood donors with iron-deficient erythropoiesis will donate one unit of red blood cells (RBC) and a ⁵¹Cr-labelled post-transfusion RBC recovery study will be performed after 40–42 days of refrigerated storage. Each volunteer will then be randomised to receive placebo (intravenous saline) or iron repletion (1 g intravenous low molecular weight iron-dextran) within 4 weeks of completing the post-transfusion RBC recovery study. Five months ± 4 weeks later they will donate another RBC unit. Then 40–42 days after the second blood donation, another ⁵¹Cr-labelled post-transfusion RBC recovery study will be performed and the result will be compared to that of the first ⁵¹Cr-labelled post-transfusion RBC recovery study. IV: intravenous.