Risk Factors for Blood Product Usage Following Sibling Allogeneic Haemopoietic Stem Cell Transplantation (allo-HCT).

Red cell and platelet transfusion requirements have been reported to be lower following reduced intensity conditioning allogeneic hematopoietic stem cell transplantation (RIC allo-HCT) when compared to myeloablative (MA) allo-HCT. However, previous studies examined RIC regimens with lower haemopoietic toxicity than many of the regimens in use today. We investigated risk factors for red cell and platelet transfusion in patients enrolled prospectively in an Australian study investigating the non-HLA immunogenetics of sibling allo-HCT. The transfusion requirements in the first year post transplant were reviewed for 122 patients transplanted between 2002 and 2006 in three Australian transplant centres. Seventy-one patients received MA and 51 RIC regimens. Using regression analysis, the outcome variables of total red cell and platelet units transfused were analysed. The factors age, transplant centre, disease, transplant type (RIC v MA), days of neutropenia, death within 12 months, disease risk (high risk (HR) v standard risk (SR)) and ABO mismatch underwent univariate analysis. Associated variables with p<0.2 were included in a multivariable analysis. Duration of neutropenia, disease risk, death within 12 months and transplant centre were significantly associated with higher red cell and platelet usage (p<0.0001). Transplant type was not associated with transfusion requirement. Each additional day of neutropenia resulted in a 9% increase in number of red cell units transfused and 11% of platelet units. HR MA patients used an estimated 17 units of red cells compared to 12 units for SR. HR RIC patients used an estimated 26 units compared to 10 for SR RIC patients. HR patients used an estimated 16.9 platelet units compared to 8.5 for low risk. These data highlight the importance of disease risk and degree of myelosuppression as key risk factors for blood product usage following allo-HSCT.