Long-term course of hemoglobin and ferritin values in high-frequency blood donors donating whole blood or double erythrocyte apheresis

Background: Serum ferritin (SF) measurements in whole blood (WB) donors demonstrated that female sex and intensity of donation are major risk factors for iron deficiency. Approximately 200 mL red blood cells (RBC) and 200–240 mg iron are lost with WB donation. Double unit RBC (2RBC) collections of 360 mL (ca. 40 mL less than the RBC amount of two WB donations) lead to a loss of about 400 mg iron. In Switzerland, the maximal allowed donation frequency for male donors is once every 6 months for 2RBC and once every 3 months for WB donation. Aims: To describe and compare the course of hemoglobin (Hb) and SF in male subjects donating WB and 2RBC at our institution. Methods: We included 294 WB and 151 2RBC donors (n = 445) who donated with the maximal allowed donation frequency over 48 months between 2008 and 2013, yielding 4,704 WB and 1,208 2RBC donations. We excluded subjects with hyperferritinemia and known HFE mutations. Hb limits were 135 g/L for WB and 140 g/L for 2RBC donation. With 2RBC apheresis 360 mL RBC were collected. SF was measured on a predonation serum sample; Hb was determined from finger prick samples. The donors received no iron substitution. We used generalized estimating equation models for Hb and SF trajectories. Results: Mean age at the first blood donation was 53 (WB) and 48 years (2RBC), respectively. At the first donation, mean Hb was 153 g/L (SD 13) in WB and 159 g/L (SD 8) in 2RBC donors; mean SF was 44 (SD 52) and 73 lg/L (SD 56), respectively. On average, Hb and SF were higher in 2RBC donors (5.1 g/L and 26 lg/L, respectively; P 30 lg/L) and 40, respectively. In 2RBC donors, between the first and the last donation, mean Hb declined from 159 g/L to 157 g/L (P < 0.05) and mean SF from 73 lg/L to 66 lg/L (ns). In WB donors, mean Hb dropped from 153 g/L to 152 g/L (P < 0.05) and SF from 44 lg/L to 35 lg/L (P < 0.001). Similar results were found when adjusting for age and season. Hb values dropped from baseline until the 11th donation for WB donors and until the 4th donation for 2RBC donors with an upward trend thereafter. In both groups, no Hb value below the limits of blood donation and no anemia were observed. SF reached a nadir at the 4th donation in both WB and 2RBC donors (37 lg/L and 60 lg/L) and increased thereafter in 2RBC donors. In WB donors, SF followed a parabolic trend that peaked at the 10th donation, and then declined until the last donation. Summary/Conclusions: The maximal allowed blood donation frequency for WB and 2RBC male donors in Switzerland is not only protective for the development of anemia, but also for deferral of blood donors because of low Hb. This was observed even in subjects with low SF at baseline