TUESDAY, May 20 (HealthDay News) -- U.S. blood collection centers face a conundrum: At a time of decreasing blood donations, a new study shows that an important source of current and future donations, 16- and 17-year-olds, are more likely to bruise, faint or experience other complications when they donate.

That means this critical pool of young donors may be less likely to give in the future, experts say.

"Most donors in all age groups have uncomplicated donations," stressed Dr. Anne Eder, executive medical officer of biomedical services at American Red Cross National Headquarters in Washington, D.C. "What was surprising was how much young donors contribute to the blood supply. The other important finding was that 16- and 17-year-olds were more likely to return to give blood again, but even a minor reaction like dizziness or other symptoms will reduce the likelihood that they will donate again."

Eder is lead author of a study published in the May 21 issue of the Journal of the American Medical Association.

Due to factors including increased restrictions -- such as screening for West Nile virus and Chagas disease -- only an estimated 38 percent of the U.S. adult population is currently eligible to donate blood.

Between 2001 and 2004, there was a 0.2 percent decrease in blood donations in the United States, even though the number of transfusions rose by 2 percent.

Luckily, donations from young people, who are less likely to have infectious diseases, have been on the rise. By 2005, donors aged 16 to 19 represented 14.5 percent of annual donation, with 16- and 17-year-olds contributing 8 percent of the units collected by the Red Cross. About 80 percent of these donations come from high school blood drives. At the same time, the rate of donations from older individuals has declined.

The authors estimated that if 16-year-olds nationwide had the opportunity to donate blood, an additional 200,000 units of blood could be added to the current annual collection of 15 million units.

Most states allow blood donation by 17-year-olds without parental consent. Only 22 states or U.S. territories allow donation by 16-year-olds with parental consent, and just two allow donation by 16-year-olds without parental consent. The Red Cross does not accept donations from 15-year-olds, requires parental consent for 16-year-olds and follows state regulations for 17-year-olds.

However, "there is an ever- increasing demand for blood donations with a decreasing pool of donors," said Dr. Peter Richel, head of pediatrics at Northern Westchester Hospital in Mt. Kisco, New York. "Therefore, what's big is high-school blood drives. There's a sense of community and learning to give."

But will that giving continue if fainting, bruising and other problems persist?

The authors of this study analyzed data collected from nine American Red Cross blood centers that routinely collect blood from 16- and 17-year-olds.

Complications occurred in 10.7 percent of 16- to 17-year-olds and 8.3 percent of 18- to 19-year-olds. That's compared to a rate of only 2.8 percent for adults aged 20 and over.

Overall, 16- and 17-year-old donors were three times more likely to experience complications compared to donors aged 20 and above, first-time donors were almost three times as likely to experience complications compared to repeat donors, and females were almost twice as likely to experience donation-linked complications compared to males. There were some regional variations as well, the team said.

Injuries related to fainting (including concussion, stitches and broken jaws) were more than twice as frequent in 16- and 17-year-olds as in 18- and 19-year olds and more than 14.46 times as likely than in the over-20 group.

These incidents can influence the willingness of young donors to donate blood again, the researchers found. Only 52 percent of 16-year-olds who experienced a problem, no matter how minor, returned for a repeat donation within a year, versus 73 percent of those whose donation went smoothly.

"We want donors to have a good experience, and there are a number of ways to do that. Every step is important," Eder said. "We collect these safety data so we have a baseline and can monitor and further our effort to improve the donor's experience."

Steps already well-known to reduce donation-linked problems include drinking lots of water, getting a good night's sleep and eating a nutritious meal before hooking up to the IV, experts say.

More information

For more on giving the gift of life, head to the American Red Cross.

SOURCES: Anne F. Eder, M.D., Ph.D., executive medical officer, biomedical services, American Red Cross National Headquarters, Washington, D.C.; Peter Richel, M.D., chief of pediatrics, Northern Westchester Hospital, Mt. Kisco, N.Y.; May 21, 2008, Journal of the American Medical Association

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