Female adolescent blood donors are at greater risk of having low iron stores and iron deficiency anemia compared to adult female blood donors and nondonors, which could have significant negative consequences on their developing brains, according to a new study published in the journal Transfusion.
When left untreated, anemia can lead to exhaustion, fatigue and cognitive dysfunction. Research has also shown a link between iron deficiency and psychiatric disorders, including mood disorders, depression and autism spectrum disorder (ASD).
Each year, approximately 6.8 million Americans donate blood, according to the American Red Cross. Teens are increasingly contributing to the donor pool due to blood drives at high schools. In 2015, for example, 16- to 18-year-olds gave around 1.5 million blood donations.
Blood donation can increase the risk of iron deficiency as each whole blood donation removes about 200-250 milligrams of iron from the donor. Since teenagers tend to have lower blood volumes when donating the same amount of blood, they have a relatively higher proportional loss of hemoglobin, the iron-containing protein in blood cells that transports oxygen.
As a result, they lose more iron during donation than adults. Females have an even greater risk of iron deficiency than males due to blood loss during menstruation every month.
Although blood donation is largely a safe procedure, young people are at greater risk for acute, adverse donation-related problems, such as injuries from fainting during donation, said study leaders Eshan Patel, M.P.H., a biostatistician in the Department of Pathology at the Johns Hopkins University School of Medicine, and Aaron Tobian, M.D., Ph.D., professor of pathology, medicine, oncology and epidemiology at the Johns Hopkins University School of Medicine and director of transfusion medicine at The Johns Hopkins Hospital.
Several studies have found that younger age, female sex and increased frequency of blood donation are all linked to lower serum ferritin levels (a surrogate for total body iron levels) in blood donor populations. However, no study using nationally representative data has compared the prevalence of iron deficiency and associated anemia between blood donor and nondonor populations, specifically in teens, say the researchers.
In the new study, the Johns Hopkins researchers looked at data from the National Health and Nutrition Examination Survey which included 9,647 female participants 16 to 49 years old who had provided both samples and blood donor history information. There were 2,419 adolescents between the ages of 16 and 19 in this group.
Around 10.7 percent of the teens had donated blood within the past 12 months, compared with about 6.4 percent of the adults. Mean serum ferritin levels were significantly lower among blood donors than among nondonors in both the adolescent and the adult populations.
The prevalence of iron deficiency anemia was 9.5 percent among adolescent donors and 7.9 percent among adult donors — both low numbers, but still significantly higher than that of nondonors in both age groups, which was 6.1 percent. Besides, 22.6 percent of adolescent donors and 18.3 percent of adult donors had absent iron stores.
Overall, the results highlight the vulnerability of adolescent blood donors to associated iron deficiency.
The researchers note that some federal policies and regulations are already in place to protect donors in general from iron deficiency due to this altruistic act, such as hemoglobin screening, a minimum weight to donate and an eight-week interval between donations for repeat whole blood donation.
However, more protections are needed for teen donors; for example, suggesting oral iron supplementation, raising the minimum time interval between donations or donating other blood products such as platelets or plasma rather than whole blood could help reduce iron loss, say the researchers.
“We’re not saying that eligible donors shouldn’t donate. There are already issues with the lack of blood supply,” Tobian said. “However, new regulations or accreditation standards could help make blood donation even safer for young donors.”
Source: Johns Hopkins Medicine