s mail survey conducted in 1998 as part of The Retrovirus Epidemiology Donor Study (REDS). Survey respondents were from eight large U.S. blood centers. Of the 52, 650 blood donors who returned questionnaires, scientists identified 197 who reported a diagnosis of hemochromatosis. Analyses were restricted to donors who reported hemochromatosis and did not indicate some other health-related reason motivating them to donate blood.
Although nearly 46 percent of hemochromatosis donors reported that their primary motivation for donating was to treat their illness, the prevalence of unreported risk factors for transfusion-transmissible viral infections (TTVIs) was similar for patients with hemochromatosis (2 percent) and for donors who did not donate for a health reason (3.1 percent). The overall prevalence of positive screening tests for TTVI, a measure of possible viral infection, was also similar in both groups 1.3 percent of hemochromatosis patients versus 1.6 percent of donors who did not have a health reason to donate.
"The importance of blood donations from hemochromatosis patients may increase even further. Recent improvements in diagnosis may lead to even larger estimates of hemochromatosis prevalence," said Dr. George Schreiber, principal investigator of the REDS coordinating center at Westat.
Prevalence estimates may also change as a result of an ongoing study funded by NHLBI that is screening large populations in an effort to find genetic markers for hemochromatosis.
Almost 90 percent of hemochromatosis donors in the survey gave blood at centers whose policy was to defer all hemochromatosis patients, thus restricting them from donating. The study authors propose several explanations for this, including the possibility that current risk factor screening at blood collection centers may not detect all cases of hemochromatosis. Alternatively, donors may either intentionally not report their condition so they can donate or they may fail to report their condition because of miscommunications with blood bank staff. They are not asked directly whether they have hemochromatosis but whether they have "a blood disease."
Current FDA regulations for blood donation do not prohibit blood from hemochromatosis patients. However, unless the blood center has an FDA variance, all blood that is drawn during therapeutic phlebotomies must be labeled and the source indicated. It is then up to physicians and their patients to decide whether they want to use the blood. Schreiber and REDS study co-authors note that labeled blood is usually not well accepted and is often discarded. In 1999, the FDA began granting variances to blood collection organizations that offer free phlebotomies to all patients with hemochromatosis. The variances allow blood to be collected from these patients without special labeling. However, to qualify for a variance, the blood collection organization must bear the cost of the free phlebotomies. Only a small percentage of licensed and registered blood collection facilities have requested and received variances.
To arrange an interview with an NHLBI scientist, contact the NHLBI Communications Office at (301) 496 - 4236. To interview Dr. Schreiber, call (301) 251-8203; to interview Ana Sanchez, MHS, of Westat, the lead author of the study, call (301) 251-2268.
NHLBI press releases, fact sheets, and other materials are available online at www.nhlbi.nih.gov.