Studies on markers for bleeding risk among thrombocytopenic cancer patients are lacking. This prospective observational cohort study investigated whether platelet parameters and a standardised bleeding questionnaire predicted bleeding or prophylactic platelet transfusions in patients with cancer and thrombocytopenia. Admitted adult patients with cancer and platelet count <80 × 10(9)/L were enrolled, but excluded if they experienced surgery or trauma within 7 days or platelet transfusion within 14 days. Patients were interviewed, blood samples collected and, subsequently, spontaneous bleeding and prophylactic platelet transfusion within 30 days were registered. Of 197 patients enrolled, 56 (28%) experienced bleeding. In multivariate analyses, predictors of bleeding were infection (adjusted odds ratio (OR) = 2.65 and 95% confidence interval (95% CI) 1.04-6.74); treatment with platelet inhibitors, heparin or warfarin OR = 2.34, 95% CI 1.23-4.48; urea nitrogen OR = 1.15, 95% CI 1.07-1.25; creatinine OR = 1.01, 95% CI 1.01-1.01; and haemoglobin OR = 0.62, 95% CI 0.41-0.93. Specific information regarding previous gastrointestinal bleeding OR = 3.33, 95% CI 1.19-9.34 and haematuria OR = 3.00, 95% CI 1.20-7.52 predicted bleeding whereas the standardised bleeding questionnaire did not. Prophylactic platelet transfusions were administered to 97 patients. Predictors of prophylactic platelet transfusions were: platelet count OR = 0.96, 95% CI 0.94-0.97; fibrinogen OR = 0.88, 95% CI 0.83-0.95; mean platelet volume OR = 0.69, 95% CI 0.49-0.97; platelet aggregometry with OR = 2.48, 95% CI 1.09-5.64 for collagen-induced platelet aggregation within the lowest quartile; and albumin OR = 1.07, 95% CI 1.01-1.15. In conclusion, except for immature platelet fraction (IPF), platelet parameters predicted prophylactic platelet transfusion but not bleeding. Bleeding risk factors were previous haematuria or gastrointestinal bleeding, infection, antiplatelet or anticoagulant treatment, high urea nitrogen, low haemoglobin or high creatinine.
Keywords: Bleeding; bleeding questionnaire; platelet function; platelet transfusion; thrombocytopenia.