Oral iron supplementation after blood donation: A randomized clinical trial

Abstract

Importance: Although blood donation is allowed every 8 weeks in the United States, recovery of hemoglobin to the currently accepted standard (12.5 g/dL) is frequently delayed, and some donors become anemic. Objective: To determine the effect of oral iron supplementation on hemoglobin recovery time (days to recovery of 80% of hemoglobin removed) and recovery of iron stores in iron-depleted ("low ferritin,"26 ng/mL) and iron-replete ("higher ferritin," >26 ng/mL) blood donors. Design, Setting, and Participants: Randomized, nonblinded clinical trial of blood donors stratified by ferritin level, sex, and age conducted in 4 regional blood centers in the United States in 2012. Included were 215 eligible participants aged 18 to 79 years who had not donated whole blood or red blood cells within 4 months. Interventions: One tablet of ferrous gluconate (37.5mg of elemental iron) daily or no iron for 24 weeks (168 days) after donating a unit of whole blood (500 mL). Main Outcomes and Measures: Time to recovery of 80% of the postdonation decrease in hemoglobin and recovery of ferritin level to baseline as a measure of iron stores. Results: The mean baseline hemoglobin levels were comparable in the iron and no-iron groups and declined from a mean (SD) of 13.4 (1.1) g/dL to 12.0 (1.2) g/dL after donation in the low-ferritin group and from 14.2 (1.1) g/dL to 12.9 (1.2) g/dL in the higher-ferritin group. Compared with participants who did not receive iron supplementation, those who received iron supplementation had shortened time to 80% hemoglobin recovery in both the low-ferritin and higher-ferritin groups. Recovery of iron stores in all participants who received supplements took a median of 76 days (IQR, 20-126); for participants not taking iron, median recovery time was longer than 168 days (IQR, 147->168 days; P 26 ng/mL).