Abstract We evaluated 52 MDS patients who had received at least one RBC transfusion. In the 4-week period following the first transfusion, 24 patients (group 1) required no transfusion while 28 (group 2) required transfusion of 2 or more units of RBC. Survival was greater in group 1 (440 weeks vs. 167 weeks, p<0.01), even when only IPSS low and intermediate-1 risk patients were analyzed (median OS 491 vs. 170 weeks, p<0.05), independent of age, IPSS, and progression to AML. The intensity of transfusion required in the first few weeks after the first transfusion predicts disease severity and correlates with survival.