Estimated median density identifies donor age and sex differences in red blood cell biological age

Abstract Background Donors possess heterogeneous red cell concentrates (RCCs) in terms of the biological age of their red blood cells (RBCs) as a direct result of various donor‐dependent factors influencing rates of erythropoiesis. This study aimed to estimate the median biological age of RBCs in RCCs based on donor age and sex to investigate inherent differences in blood products' biological ages over hypothermic storage using estimated median densities (EMDs). Study Design Sixty RCCs were collected from four donor groups; male and female teenagers (17–19 years old) and seniors (75+ years old). A Percoll density‐based separation approach was used to quantify the EMDs indicative of biological age. EMD and mean corpuscular hemoglobin (MCHC) were compared by correlation analyses. Results Differences in the median biological age of RCC units were observed with male donors having significantly higher EMDs compared to females ( p 0.5). Conclusions This study provides further evidence that there are inherent differences between the biological age profiles of RBCs between blood donors of different sex and age. Our findings further highlight that biological age may contribute to RBC quality during storage and that donor characteristics need to be considered when evaluating transfusion safety and efficacy.