Donation-Induced Protein and Iron Depletion in High-Frequency Plasma Donors

Demands for plasma continue to rise, but the effects of frequent donations on donor-health remain unclear. The aim of this observational study was to assess associations of plasma donation frequencies with biomarker (protein, ferritin, and hemoglobin) levels, and to evaluate the contribution of high or very high-frequency donors to the collected plasma. We included all plasma donors (N = 42,390) of 2019 who donated only plasma in 2 preceding years. Total protein and hemoglobin were measured in all donors, ferritin only in a subpopulation (N = 953). Associations between the number of donations and biomarker levels were analyzed using linear regression, adjusted for age and days since previous donation, and stratified by sex and menopausal status. We grouped the donors based on their yearly donation frequency: low frequency (LF) 1 to 6, medium frequency (MF) 7 to 12, high frequency (HF) 13 to 18 and Very High Frequency (VHF) >18. Linear regression analyses showed significant negative associations between numbers of donations and protein (odds ratios: males -0.04 (-0.05 to -0.03), premenopausal females -0.09 (-0.11 to -0.03), postmenopausal females -0.05 (-0.07 to -0.04)) and ferritin levels (odds ratios: males -1.98 (-2.47 to -1.48), premenopausal females -1.81 (2.23 to -0.75), postmenopausal females -1.24 (-2.10 to -0.38)). HF- and VHF-donors (6% of donors) are predominantly male with high donation volumes, contributing approximately 17% to the amount of collected plasma. High-frequency plasma donations are associated with significantly lower protein and ferritin, but not Hb levels. Despite the low number of HF- and VHF-donors, their contribution to the plasma supply is high.