Why many would-be bone marrow, blood stem cell donors back out

Upon being identified as potential bone marrow or blood stem cell donors, many people choose not to participate. As result, patients with blood cancers go without life-saving treatments.

About 40% of whites and 60% of nonwhites opt out of donating when contacted for confirmatory testing by blood sample, according to data from the National Marrow Donor Program and Be The Match. Why? That's the question researchers attempted to answer in a recent study.

"The most consistent factor associated with opting-out of the registry across all race/ethnic groups was ambivalence about donation - doubts and worries, feeling unsure about donation, wishing someone else would donate in one's place," writes Galen Switzer, a professor of medicine and psychiatry at the University of Pittsburgh, in the study , published in December in the journal Blood.

 "We wanted to know what might explain the higher rates at which ethnic minorities opt out of the registry when they're contacted as a potential match," says Switzer, the lead study author.

"Some of the ethnic groups had less trust that the stem cells that were collected would be allocated equitably. Members of ethnic minorities groups were also more likely to have been discouraged by someone else from donating."

For example, in phone interviews, minorities were more likely to disagree with the statement: "Stem cells go to the person who needs them most regardless of their race."

To increase would-be donor participation among all groups, the study authors suggest screening potential donors for "ambivalence", and then addressing more of the ambivalent donors' concerns head-on before they opt out unnecessarily.

"The ultimate goal in mitigating doubts and worries about donating," says Switzer, "is to ensure that potential donors are fully educated, confident, and most importantly, comfortable with their decision, no matter what choice they make."