Risk of bleeding and use of platelet transfusions in patients with hematologic malignancies: recurrent event analysis

A recent randomized trial (TOPPS) compared prophylactic platelet transfusions (for counts <10x109/L) with a strategy of no-prophylaxis in adults with hematologic malignancies. 70% of enrolled patients received autologous hematopoietic stem cell transplant (HSCT). In this analysis, statistical models were developed to explore which patient factors or clinical characteristics are important prognostic factors for bleeding. These models were presented for baseline characteristics and for recurrent analysis of bleeding to assess the risks of WHO grade 2-4 bleeding on any given day. Additional analyses explored the importance of fever. Treatment plan (chemotherapy/allogeneic hematopoietic stem cell transplant), female sex, and treatment arm (no-prophylaxis) were significantly associated with increased number of days of bleeding. The number of days with a platelet count <10x109/L was significantly associated with a grade 2-4 bleed (p<0.0001). Patients with a temperature of at least 380C had the highest hazard of a grade 2-4 bleed (HR: 1.7, 95% CI: 1.3 to 2.4, versus temp <37.50C). There was no evidence that minor bleeding predicted a grade 2-4 bleed. The results highlighted the limited role of correction of thrombocytopenia by platelet transfusion to reduce risk of bleeding. Clinically stable patients undergoing autologous HSCT had the lowest risk of bleeding and benefited least from prophylactic platelet transfusions. Prospective studies are required to address the usefulness of risk factors to support better targeted platelet transfusions. TOPPS Controlled-Trials.com number ISRCTN08758735.