Bethesda, Md. – African American and Asian blood donors appear to be less likely to have lower levels of iron stores compared with non-Hispanic white donors, while Hispanic donors appear to have a greater risk for low iron, according to findings from an analysis of more than 12,000 donors. The findings were presented at the 2017 AABB Annual Meeting, held Oct. 7-10 in San Diego.
Researchers found that African American and Asian donors were 14% and 34% respectively less likely to have low ferritin levels compared to non-Hispanic white donors, while Hispanic donors were 19% more likely to have low ferritin. Ferritin is a measure of iron stores in the body. Iron is necessary for transporting oxygen throughout the body via red blood cells. It is also important for respiration, energy metabolism, and joint and brain function. Low ferritin was defined as less than 26 ng/mL.
Similar results were seen for a more severe level of iron depletion, absent iron stores (AIS), which is a ferritin level <12 ng/mL. African American and Asian donors were 19% and 24% respectively less likely than non-Hispanic white donors to have AIS, while Hispanic donors were 25% more likely. These results are derived from statistical models that control for age, sex, body weight, donation frequency and other factors. The researchers also found that rates of low ferritin and AIS were 42% and 19% respectively for the entire cohort. The cohort was enriched with about 2,300 high frequency donors, but otherwise represents otherwise mostly unselected populations within each stratum of race/ethnicity.
“The findings are useful in helping us understand at a more granular level some of the drivers of iron status in donors. We know that blood donation itself is an important factor because they are losing about 250 mg of iron per donation,” said lead author Bryan Spencer, PhD, a researcher at the American Red Cross and program manager of the Yale/ARC “domestic hub” of the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) program, sponsored by the National Heart, Lung, and Blood Institute (NHLBI).
The data for this analysis comes from the Red Blood Cell-Omics (RBC-Omics) study, which is part of the REDS-III program. More than 12,600 donors have been enrolled in the study at four U.S. blood centers. Participants completed questionnaires on demographics and risk factors for iron depletion, and blood samples were tested for ferritin levels.
Some other findings were as expected. Risk of low ferritin and AIS increased sharply with increasing donation intensity, while women older than 50 years — around the average age of menopause — had a large dip in risk. Daily use of external iron, such as supplements, reduced the risk of low ferritin and AIS by 30% and 40% respectively.
The researchers also found that the regular use of antacids was associated with at least a 20% increase in risk for low iron. Oral contraceptive or estrogen use in women was associated with a 15%-20% lower risk. Reported supplemental testosterone use by men, conversely, was associated with double the risk of AIS.
The findings suggest that existing iron mitigation strategies based on age and gender “could be further refined depending on a given blood center’s operational context and donor population,” the researchers concluded.
AABB is an international, not-for-profit association representing individuals and institutions involved in the fields of transfusion medicine and cellular therapies. The association is committed to improving health through the development and delivery of standards, accreditation and educational programs that focus on optimizing patient and donor care and safety. AABB membership includes physicians, nurses, scientists, researchers, administrators, medical technologists and other health care providers. AABB members are located in more than 80 countries and AABB accredits institutions in more than 50 countries.