Attrition at the final donor stage among unrelated haematopoietic stem cell donors: the British Bone Marrow Registry experience.

Abstract

To investigate attrition at the finally selected donor stage among British Bone Marrow Registry (BBMR) donors, all recruited from blood donors. The success of searches for unrelated stem cell donors relies on the existence of large international donor registries and the availability of registered donors when matched with a patient. Withdrawal of donors may adversely affect patient outcomes. Data on 2942 planned donations were analysed to assess donor-related deferral rates and associated factors. Overall, 20·2% of requests were cancelled. Transplant centres activated more than half of the cancellations (52·6%). Donor reasons accounted for 46·7% of cancellations (9·4% of requests), of which 61·7% happened for medical and 38·3% for personal reasons. Medical ineligibility of the donor was associated with increasing age (odds ratio [OR]=1·36, P=0·011) and peripheral blood stem cell source (OR=2·22, P=0·006), and there was some evidence of association with low blood donation reliability (OR=1·52, P=0·054). The blood donor reliability score relates to blood donation, and the score worsens if donors consistently fail to attend a donation session when invited. Withdrawal on personal grounds showed associations with donor age (OR=1·72, P=0·017, 30-40 years vs other ages), peripheral blood stem cell source (OR=2·43, P=0·010) and low blood donor reliability (OR=1·94, P=0·007). To our knowledge, this is the first report on all-cause cancellation at the finally-selected donor stage for international stem cell donor provision, showing 9·4% donor-related cancellation rate. Scores associated with blood donation reliability may be useful to predict stem cell donor withdrawal.