Iron supplements speed hemoglobin recovery after blood donation

Last Updated: 2015-02-11

By Anne Harding

NEW YORK (Reuters Health) - Taking iron supplements can help frequent blood donors avoid anemia, according to new findings published online February 10 in JAMA.

Current U.S. guidelines allow people to donate blood every eight weeks, Dr. Alan Mast, of the Blood Center of Wisconsin in Milwaukee, and colleagues note in their report. "It takes longer than that for blood donors to recover their iron stores, especially if they're not taking an iron supplement," Dr. Mast told Reuters Health in a telephone interview.

The American Red Cross and other groups are trying to get the word out that people who donate blood frequently should take an iron supplement, Dr. Mast added. "Just eating iron-rich foods doesn't do it."

To investigate whether iron supplementation would speed up donors' hemoglobin recovery time, Dr. Mast and his colleagues randomly assigned 215 blood donors at four regional blood centers to receive a tablet of ferrous gluconate containing 37.5 milligrams of elemental iron for 24 weeks after donating one unit of whole blood, or no iron. The donors, none of whom had given blood in the previous four months, were divided into low ferritin (26 ng/mL or below) or higher ferritin (above 26 ng/mL) groups.

After donation, hemoglobin levels declined from a mean of 13.4 g/dL to 12 g/dL in the low-ferritin group, and from 14.2 g/dL to 12.9 g/dL in the higher-ferritin group. Time to recovery of 80% of the post-donation decrease in hemoglobin, along with recovery of ferritin to baseline, was a median of 76 days for donors who were taking iron supplements, and 168 days for those who were not taking iron. Two-thirds of the donors who were not taking iron had not recovered their iron stores by 168 days after donation.

While the frequency of gastrointestinal side effects was low among the study participants who took iron, Dr. Mast noted, this may have been because donors who took part in the study received $25 per visit. "They might not have complained as much about their (gastrointestinal) GI upset," he said.

Anyone who donates blood more than once a year should talk to their personal physician or pharmacist about the best type of iron supplementation for them, Dr. Mast added. Also, he said, it's important for physicians to ask patients with iron deficiency whether they donate blood often, which could help avoid the need for costly tests, like colonoscopy to check for gastrointestinal bleeding.

Supplementation can also reduce the rate of low-hemoglobin donor deferrals, Dr. Mast and his team note, which occur in 17.7% of female presenting donors and 1.6% of men, due to their having a capillary hemoglobin below 12.5 g/dL.

People who give blood just once a year probably don't need to take iron, Dr. Mast said, while people who do donate blood frequently but would prefer not to take iron supplement should consider delaying repeat donation for six months or longer.

This research was supported by the National Heart, Lung, and Blood Institute. Dr. Mast reports receiving support from Novo Nordisk and Siemens; no other authors report any disclosures.

SOURCE: http://bit.ly/1EYTVdl

JAMA 2015.