Among blood donors with normal hemoglobin levels, low-dose oral iron supplementation, compared with no supplementation, reduced recovery time of the post-donation decrease in hemoglobin concentration in donors with low or higher levels of ferritin (a marker of overall iron storage), revealed researchers at Institute for Transfusion Medicine, Pittsburgh.
It is estimated that 25-35 percent of blood donors become iron depleted from regular blood donation. Recovery of hemoglobin to the currently accepted standard is frequently delayed, and some donors become anemic. Iron depletion is associated with fatigue, decreased exercise capacity and neurocognitive changes.
Researchers randomly assigned 215 eligible study participants (who had not donated whole blood or red blood cells within 4 months) to receive one tablet of ferrous gluconate (37.5 mg of elemental iron) daily or no iron for 24 weeks after donating a unit of whole blood (500 ml). They found that compared with participants who did not receive iron supplementation, those who did had shortened time to 80 percent hemoglobin recovery in both the low-ferritin (average 32 days vs 158 days) and higher-ferritin groups (average 31 days vs 78 days). Recovery of iron stores in all study participants who received supplements took a median of 76 days; for participants not taking iron, median recovery time was longer than 168 days. Without iron supplementation, 67 percent of participants did not recover iron stores by 168 days.
The authors wrote, "Although the absolute amount of hemoglobin decrease was relatively small and of marginal clinical consequence after a single blood donation, donating blood is an iterative [repeated] process that leads to progressive iron loss and anemia in some frequent blood donors, so it is important that the hemoglobin decrease after blood donation be recovered before the next blood donation."
The study is published in 'JAMA'.