Influence of blood donation on iron stores assessed by serum ferritin and haemoglobin in a population survey of 1433 Danish males.

The general impact of blood donation on iron status has been studied in Danish males. Iron stores were assessed by serum (S-) ferritin and haemoglobin (Hb) in a population survey comprising 1433 males in age cohorts of 30, 40, 50, and 60 years; 389 (27%) were blood donors and 1044 (73%) non-donors. Hb levels were identical in donors and non-donors, mean 155 +/- 11 (SD) g/l (9.6 +/- 0.7 mmol/l); values less than 129 g/l (8.0 mmol/l) were observed in 1.3% of donors vs 1.9% of non-donors. Correlations between S-Ferritin and Hb were slight and without practical clinical relevance: rS = 0.13, p less than 0.01 in donors vs rS = 0.16, p less than 0.0001 in non-donors. Donors had lower S-Ferritin, median 95 micrograms/l, than non-donors, median 136 micrograms/l (p less than 0.0001). S-Ferritin values less than 15 micrograms/l (i.e. depleted iron stores) were seen in 3.3% of donors vs 0.4% of non-donors, and S-Ferritin values of 15-30 micrograms/l (i.e. small iron stores) in 9.8% of donors vs 1.4% of non-donors. Iron-deficiency anaemia (i.e. S-Ferritin less than 15 micrograms/l and Hb less than 129 g/l) was seen in 0.26% of donors vs 0.10% of non-donors; employing the 5th percentile for Hb (137 g/l (8.5 mmol/l] as discriminatory value increased the percentage of iron-deficiency anaemia to 0.51% in donors vs 0.10% in non-donors. Blood donation had a marked influence on iron status in the adult male population. The frequency of phlebotomy should be adjusted according to S-Ferritin as well as Hb levels. If Hb is used as single criterion for donation, only donors with pre-donation values greater than or equal to 135-137 g/l should be allowed phlebotomy. Optimal donation standards should include monitoring of iron status through measurement of S-Ferritin and Hb, combined with individualised postdonation iron supplementation.